基于Tween80和两亲共聚物PVDF超滤膜结构调控及其性能表征
|
摘要
超滤膜已广泛应用于生物、医药、食品、血液处理、废水和超纯水等方面。作为性能优良的新型聚合物膜材料,聚偏氟乙烯(PVDF)具有优良的化学稳定性、热稳定性、机械稳定性以及低介电常数、低表面能、耐射线、紫外线辐射等性质,近年来在膜分离技术中的应用越来越广泛。但是,PVDF极低的表面能导致其可润湿能力很差,在分离油/水体系(尤其是含蛋白质或活性生物体的溶液)时,容易发生膜污染。膜污染易导致膜分离性能下降,使用寿命缩短,操作成本增加。因此,如何提高PVDF的亲水性、降低膜污染及对膜结构调控一直是研究的热点之一。本文采用小分子表面活性剂Tween-80和两亲共聚物大分子表面润湿剂调控PVDF亲水膜的结构,并对其性能进行表征。优化PVDF平板膜制备方法,制备出渗透性能良好、机械性能高的PVDF中空纤维亲水超滤膜。论文研究结果如下：
首先,选用Tween-80和H2O为混合添加剂,在纯水凝胶浴中采用非溶剂致相(NIPS)法制备PVDF平板膜。动态光散射(DLS)结果表明,铸膜液中的非溶剂H20被Tween-80在DMAc中形成的反胶束增溶,形成反胶束的“水池”；Tween-80的极性基团与H2O之间的相互作用提供了PVDF与反胶束疏水外壳之间作用力的平衡力,从而提高了铸膜液的热稳定性；PVDF膜的通量、机械强度和截留等均提高,其结果如下：在适宜的制膜条件下制备的PVDF膜在0.1MPa操作压力下的纯水通量为192L ·m-2·h-1;对牛血清(BSA)和葡聚糖(Dextran, MW70K)的截留率分别为88.3%和83.8%；断裂强度为1.3MPa、断裂伸长率为42.2%、杨氏模量为32.2MPa。固定铸膜液中Tween-80的含量(3.0wt.%)不变,当增加非溶剂H2O的含量时,PVDF膜纯水通量分别增加了1.7倍(60℃C铸膜液制膜)和2.3倍(室温250C铸膜液制膜)；PVDF膜的机械强度和接触角均随非溶剂H2O含量的增加而增加,但PVDF膜对BSA和Dextran的截留率变化不大。
其次,通过改变凝胶浴组成和铸膜液温度,研究了Tween-80和H2O混合添加剂对PVDF平板膜的结构调控路径,并从PVDF-DMAc-Tween-80-H2O体系制得具有优良机械性能和双连续结构的PVDF亲水膜。选用的凝胶浴为乙醇-水混合凝胶浴(50：50,质量比)和纯乙醇凝胶浴,重点研究了Tween-80和H2O混和添加剂的组成、铸膜液温度和凝胶浴组成对铸膜液物理-化学性能和PVDF膜结构性能的影响。结果表明,凝胶浴组成决定了铸膜液的液液分相和液固分相的顺序和范围,而Tween-80和H2O混和添加剂和铸膜液温度影响了铸膜液的凝胶速率。凝胶过程中,Tween-80反胶束增溶的非溶剂H2O从铸膜液内部扩散,导致铸膜液凝胶速率加快和Tween-80的亲水基团向膜表面的迁移。铸膜液在纯乙醇凝胶浴中的延迟分相有利于树叶状多孔表面和膜断面针状纳米晶粒的形成。制得的PVDF平板膜的通量和亲水性都明显改善。而铸膜液在乙醇-水混合凝胶浴中则呈现较短时间的延迟分相,即液国分相和液液分相同时进行。Tween-80和H20混合添加剂的存在、高温铸膜液和乙醇-水混合凝胶浴的共同作用,导致PVDF主要结晶晶型是a-β杂化晶(结晶度为59.1%)。
此外,为了解决Tween-80(?)舌性高、易溶于水、在PVDF膜制备或者PVDF膜使用过程中容易流失的问题及更好调控PVDF膜结构,采用聚乙二醇单甲醚甲基丙烯酸甲酯(PEGMA)与甲基丙烯酸甲酯(MMA)为反应单体,合成了Mn和Mw分别为66,500g/mol和34,200g/mol的两亲嵌段共聚物P(PEGMA-r-MMA),并对其结构和化学组成进行了表征；采用简单共混法,将P(PEGMA-r-MMA)反应原液(包括两亲共聚物、未反应的单体和溶剂的混合物)直接与PVDF共混,溶于TEP-DMAc (70:30,质量比)混合溶剂中,形成铸膜液,制备了结构和性能良好的PVDF-P(PEGMA-r-MMA)共混超滤膜；对铸膜液物理化学性能进行了表征,结果表明,含P(PEGMA-r-MMA)两亲共聚物的PVDF铸膜液中形成了PVDF-P(PEGMA-r-MMA)大分子聚集体。该大分子聚集体的存在导致铸膜液微观构象调整、表面张力下降、凝胶速率加快和粘度增加；讨论了反应原液的含量和凝胶浴组成对PVDF膜结构和性能的影响。结果表明,PVDF-P(PEGMA-r-MMA)大分子聚集体调控了PVDF-P(PEGMA-r-MMA)共混超滤膜的结构,且共混膜有效孔径μ分布变窄；截留分子量(MWCO)和牛血清(BSA)恢复通量均随P(PEGMA-r-MMA)两亲共聚物含量的增加而增加。
随后,为了克服简单共混法形成的大尺寸PVDF-P(PEGMA-r-MMA)大分子聚集体(粒径尺寸：100～200nm)对PVDF膜调控结构和性能改善的限制,采用原位自由基聚合反应法制备出小尺寸(粒径尺寸：0-10nm)、窄分布的PVDF-P(PEGMA-r-MMA)大分子聚集体,以强化P(PEGMA-r-MMA)两亲共聚物对PVDF膜结构的调控,并讨论了PVDF-P(PEGMA-r-MMA)大分子聚集体对PVDF膜机械强度和抗污染性能的影响。DLS和扫描电镜(SEM)结果表明,原位自由基聚合反应后的PVDF-TEP-DMAc-PEGMA-MMA铸膜液体系中形成了窄分布、小尺寸的大分子聚集体；铸膜液表面张力下降、凝胶速率加快及粘度增加；制得的PVDF膜除具有窄分布的有效孔径μ和截留分子量(MWCO)外,其μ和MWCO均随铸膜液中添加的单体混合物含量的增加而增加。结果表明,原位自由基聚合反应法增强了PVDF膜的机械强度(其良好的断裂强度、断裂伸长率和杨氏模量分别为：8.8MPa、343%和229MPa)、改善了PVDF膜正反面的亲水性；PVDF膜的主要结晶晶型是α-β杂化晶(以β晶型为主),且随铸膜液中单体混合物含量的增加,膜的结晶度从56.1%增加至81.4%。原位自由基聚合反应后的PEGMA、MMA单体更好地调控了PVDF膜结构：构成膜海绵状断面的聚合物纳米晶粒由条纹状转化为球状。
最后,在前文研究的基础上,采用实验室自制的活性更高的聚二甲基丙烯酸四氢呋喃酯(PTMGDA)代替MMA与PEGMA进行原位自由基聚合反应,制备PVDF中空纤维超滤膜。讨论了原位自由基聚合反应后的PVDF-TEP-DMAc-PTMGDA-PEGMA-PVP铸膜液体系的物理-化学性能变化,及形成的PVDF-P(PTMGDA-r-PEGMA)-PVP大分子聚集体对PVDF中空纤维膜结构调控及其渗透性能、机械强度和抗BSA污染性能的影响。结果表明,固定铸膜液中PTMGDA、PEGMA单体混合物含量不变,随着铸膜液中聚乙烯吡咯烷酮(PVP)的含量从1.0wt.%增加至3.0wt.%,PVDF中空纤维膜的海绵状断面结构中出现圆形孔道,而且构成海绵状结构的纳米聚合物晶粒的厚度增加、排列疏松,且膜的纯水通量从15.7L.m-1.h-1增加至60.2L.m-1.h-1,但PVDF膜的机械强度和对Dextran (40K和70K)的截留率变化不大；膜的接触角从78.8°降至65.2°,BSA通量恢复率(FRR)随PVP含量的增加而增加；原位自由基聚合反应后形成的P(PTMGDA-r-PEGMA)两亲共聚物与添加的PVP添加剂协同调控了PVDF中空纤维膜的结构、通量、亲水性和机械性能,并制得可应用于废水处理、生化分离等领域的PVDF中空纤维膜。
Ultrafiltration has been widely applied not only in the biological products, pharmaceutical products and food industry; but also used for blood, wastewater treatment and ultra pure water preparation. Because of its competitive mechanical properties, thermal and chemical stability, radiation resistance, etc. As one of the most popular materials for membranes preparation, polyvinylidene fluoride (PVDF) has earned lots of attention. However, PVDF membranes possess high hydrophilicity, which leads to poor wetting ability and prone to fouling, especially in the oil/water separation system, including protein or organism. This results in decreasing of performance properties, reducing the membrane life and increasing the operation cost. Thus, the fine configurations modulation of PVDF membranes with excellent hydrophilicity and high performance are always highly sought after. The self-assembled of surfactants with various molecular weights (Tween-80and amphiphilic copolymer) in organic solvents was utilized to tune the hydrophilicity, morphology and performances of PVDF membranes. Then, after optimization of preparation parameters of flat sheet PVDF membrane preparation, PVDF hollow fiber membranes possessed good permeability, hydrophilicity and excellent mechanical properties were successfuly fabricated. The results were as follows.
Firstly, PVDF membranes were fabricated by non-solvent induced phase separation (NIPS) process using Tween-80and H2O as mixture additive from both60℃and room-temperature (RT) casting solution. PVDF membranes revealed improved pure water flux (PWF), enlarged mechanical properties and well Bovine serum albumin (BSA) and Dextran rejection as a result of addition of H2O into the PVDF-DMAc-Tween-80system. The PWF of resultant PVDF was192L·m-2·h-1with0.1MPa operation pressure, and its rejection of BSA (MW67K) and Dextran (MW70K) were88.3%and83.8%, respectively. Its break strength, elongation at break and Young's modules were1.3MPa,42.2%and32.2MPa, respectively. The PWF increased to1.7times (prepared with60℃casting solution) and2.3times (prepared with ambient temperature casting solution) after addition of H2O into the casting solution. Besides, PVDF membranes'mechanical properties and dynamic contact angle increased as H2O concentration increasing. However, the rejection of BSA and Dextran of resultant PVDF membranes changed little as H2O concentration increasing. The improved performance was attributed to the existence of non-solvent, which was solubilized by the polar head groups of Tween-80reverse micelle to form the water pool. Furthermore, the interaction between polar head of surfactant and water provided a balance resistance to the interconnection between PVDF and hydrophobic chains of the surfactant, which enhanced the thermodynamics stability of casting solution.
Secondly, to obtain the target modulation path of Tween-80and H2O dopants, various compositions of coagulants and temperatures of casting solutions were utilized. PVDF membranes possessed interconnected bi-continuous structures with superior mechanical properties and fine hydrophilicity improvement were obtained from PVDF-DMAc-Tween-80-H2O system with60℃and ambient temperature casting solution, respectively. Tween-80-H2O mixtures were adopted as dope additive; water-ethanol (50:50, mass ratio) and ethanol were chosen as coagulants. The effects of process parameters in terms of variation contents of dope additives, casting solution temperatures and coagulant compositions on phase inversion process and performances of resultant PVDF membranes were investigated. Results showed that the compositions of coagulants modulated the sequence and the extent of liquid-liquid and liquid-solid demixing (crystallization), while the contents of dope additives and casting solution temperatures changed the precipitation rate of the casting solutions. During demixing process, water diffused from interior of Tween-80reverse micelles, resulting in the accelerated precipitation rate and surface segregation process of polar head groups of Tween-80. And the high temperature of casting solution contributed to the enhancing diffusion rate of liquid-liquid demixing on crystallization. The coagulant compositions changed the extent of liquid-liquid and solid-liquid demixing dynamic of casting solutions. Ethanol coagulant contributed to the crystallization of PVDF-DMAc-Tween-80-water system occurred prior to liquid-liquid demixing. This longer time-delay demixing process favored the formation of porous foliage type top-structures with fibrils or laths bi-continuous fine structure of membrane bulk, contributing to the increased flux and significant hydrophilicity improvement. While casting solutions in water-ethanol coagulant exhibited the shorter time-delay demixing process with both liquid-liquid demixing and crystallization, resulting in the formation of the fine structure in the form of the strings or stripes and limited the hydrophilic improvement. The predominant typical α and β type crystalline with crystallinity degree of59.1%in PVDF was attributed to the existence of dope additives, high temperature of casting solution and water-ethanol coagulant. This was consistent with the superior mechanical properties of corresponding PVDF membrane.
In order to avoid the high activity, soluble problem of Tween-80during PVDF membrane preparation and operating process, as well better modulation configuration of PVDF membranes, P(PEGMA-r-MMA) amphiphilic copolymer with Mn of66500g/mol and Mw of34200g/mol was synthesized via free radical polymerization choosing polyethylene glycol monomethyl ether methyl methacrylate (PEGMA) and methyl methacrylate (MMA) as reaction monomers, and its chemical structure and composition were characterized. And polyvinylidene fluoride (PVDF)-P(PEGMA-r-MMA) blend membranes were fabricated from water and ethanol coagulants via simplified blend method by directly blending PVDF and P(PEGMA-r-MMA) amphiphilic copolymer solution (including the reaction mixture) to form casting solution. The formation of the supramolecular aggregates of PVDF-P(PEGMA-r-MMA) in PVDF solution containing the copolymer were confirmed by dynamic light scattering (DLS) and scanning electron microscopy (SEM). This contributed to the micro-structure adjustment of PVDF solution and resulted in its decreasing surface tension, accelerating precipitation rate and increasing viscosity with trivial strain thinning behavior. Furthermore, the effects of the variations in dopant contents and coagulant compositions on the performances of those blend membranes were investigated. All PVDF-P(PEGMA-r-MMA) blend membranes possessed narrow distribution mean effective pore size (p.), molecular weight cut off (MWCO), improved recovery water flux after filtration experiments of BSA and tuned configurations. Compared with the instantaneous demixing process in water coagulant, the delayed demixing process in ethanol favored the pore-forming and surface segregated of the polar head group of the copolymer, which induced the increasing μ, MWCO, tunable morphologies and hydrophilicity improvement.
The results of simpilified blend method showed that the formation of the large-sized nanoparticulate aggregates (size:100～200nm) of PVDF-P(PEGMA-r-MMA) in the casting solution limited the function of the P(PEGMA-r-PEGMA) amphiphilic copolymer with respect to pore-forming and morphology modulation of the resultant membranes. Then the in situ free radical polymerization was creatively designed to obtain narrow distribution PVDF-P(PEGMA-r-MMA) supramolecular aggregates with small size and enhance better modulation configration of P(PEGMA-r-MMA); PVDF membranes with superior mechanical behaviors and enhanced antifouling properties was proven to be successfully fabricated. The DLS and SEM results verified the formation of supramolecular polymer-copolymer aggregates with small size (size:0-10nm). The narrow distribution of the supramolecular aggregates explained the decreasing surface tension, increasing viscosity with trivial strain thinning behavior and accelerating precipitation rate of the PVDF casting solution. The resultant PVDF membranes possessed narrowly distributed pore size and MWCO of the final filtration properties, which were attributed to the aggregates; additionally, their corresponding μ and MWCO increased, including the crystallinity of the a and β phase (largely in the β phase form) varied from56.1%to84.1%with increasing concentration of the monomers via in situ polymerization. Furthermore, in situ polymerization not only enlarged the recovery water flux after filtration experiments with BSA but also improved the hydrophilicity of both the top-surface and the bottom-surface of the PVDF membranes. Additionally, in situ polymerization modulated the configurations of PVDF membrane, varying from stripe-shaped grains to agglomerates of globule (with one of the globules bearing on the surface of another). The tunable morphologies, combined with the progressive enhanced crystallinity of the a and P phase were used to interpret the superior mechanical properties (Its break strength, elongation at break and Young's modules were8.8MPa,343%and229MPa, respectively) of the resulting PVDF membranes.
Finally, basic previous study, and choosing polytetrahydrofuran dimethacrylate ester (PTMGDA) that synthesied by our own lab with high reaction activity as reaction monomers instead of MMA, and reacted with PEGMA to synthesis P(PTMGDA-r-PEGMA) amphiphilic copolymer. PVDF hollow fiber UF membranes were prepared from the PVDF-TEP-DMAc-PTMGDA-PEGMA-PVP casting solution system after in situ polymerization. Combined with basic physical-chemical properties of the casting solution caused by the formation of PVDF-P(PTMGDA-r-PEGMA)-PVP supramoleculat aggregates, the configuration modulation, permeability, mechanical properties and antifouling BSA of resulant PVDF hollow fiber membranes were investigated. Results indicated that the round role appreared in the sponge-like cross-section of PVDF hollow fiber membranes, and the nanograins that constrcuted membrane bulk became widen and loose-packing as PVP concentration increasing. Besides, the membranes'pure water flux increased from15.7L.m-1.h-1to60.2L.m-1.h-1, and their mechanical properties and the rejection of Dextran (40K and70K) changed little. This showed that the synergy effects of PVP and the P(PTMGDA-r-PEGMA) amphiphilic copolymer formed via in situ polymerization on configration modulation and tuned performances of PVDF hollow fiber membranes. And the newly developed hydrophilicity PVDF hollow fiber membranes with superior mechanical properties and low-fouling of BSA are anticipated to be suitable not only for wastewater treatment, but also for bio-separation.
首先,选用Tween-80和H2O为混合添加剂,在纯水凝胶浴中采用非溶剂致相(NIPS)法制备PVDF平板膜。动态光散射(DLS)结果表明,铸膜液中的非溶剂H20被Tween-80在DMAc中形成的反胶束增溶,形成反胶束的“水池”；Tween-80的极性基团与H2O之间的相互作用提供了PVDF与反胶束疏水外壳之间作用力的平衡力,从而提高了铸膜液的热稳定性；PVDF膜的通量、机械强度和截留等均提高,其结果如下：在适宜的制膜条件下制备的PVDF膜在0.1MPa操作压力下的纯水通量为192L ·m-2·h-1;对牛血清(BSA)和葡聚糖(Dextran, MW70K)的截留率分别为88.3%和83.8%；断裂强度为1.3MPa、断裂伸长率为42.2%、杨氏模量为32.2MPa。固定铸膜液中Tween-80的含量(3.0wt.%)不变,当增加非溶剂H2O的含量时,PVDF膜纯水通量分别增加了1.7倍(60℃C铸膜液制膜)和2.3倍(室温250C铸膜液制膜)；PVDF膜的机械强度和接触角均随非溶剂H2O含量的增加而增加,但PVDF膜对BSA和Dextran的截留率变化不大。
其次,通过改变凝胶浴组成和铸膜液温度,研究了Tween-80和H2O混合添加剂对PVDF平板膜的结构调控路径,并从PVDF-DMAc-Tween-80-H2O体系制得具有优良机械性能和双连续结构的PVDF亲水膜。选用的凝胶浴为乙醇-水混合凝胶浴(50：50,质量比)和纯乙醇凝胶浴,重点研究了Tween-80和H2O混和添加剂的组成、铸膜液温度和凝胶浴组成对铸膜液物理-化学性能和PVDF膜结构性能的影响。结果表明,凝胶浴组成决定了铸膜液的液液分相和液固分相的顺序和范围,而Tween-80和H2O混和添加剂和铸膜液温度影响了铸膜液的凝胶速率。凝胶过程中,Tween-80反胶束增溶的非溶剂H2O从铸膜液内部扩散,导致铸膜液凝胶速率加快和Tween-80的亲水基团向膜表面的迁移。铸膜液在纯乙醇凝胶浴中的延迟分相有利于树叶状多孔表面和膜断面针状纳米晶粒的形成。制得的PVDF平板膜的通量和亲水性都明显改善。而铸膜液在乙醇-水混合凝胶浴中则呈现较短时间的延迟分相,即液国分相和液液分相同时进行。Tween-80和H20混合添加剂的存在、高温铸膜液和乙醇-水混合凝胶浴的共同作用,导致PVDF主要结晶晶型是a-β杂化晶(结晶度为59.1%)。
此外,为了解决Tween-80(?)舌性高、易溶于水、在PVDF膜制备或者PVDF膜使用过程中容易流失的问题及更好调控PVDF膜结构,采用聚乙二醇单甲醚甲基丙烯酸甲酯(PEGMA)与甲基丙烯酸甲酯(MMA)为反应单体,合成了Mn和Mw分别为66,500g/mol和34,200g/mol的两亲嵌段共聚物P(PEGMA-r-MMA),并对其结构和化学组成进行了表征；采用简单共混法,将P(PEGMA-r-MMA)反应原液(包括两亲共聚物、未反应的单体和溶剂的混合物)直接与PVDF共混,溶于TEP-DMAc (70:30,质量比)混合溶剂中,形成铸膜液,制备了结构和性能良好的PVDF-P(PEGMA-r-MMA)共混超滤膜；对铸膜液物理化学性能进行了表征,结果表明,含P(PEGMA-r-MMA)两亲共聚物的PVDF铸膜液中形成了PVDF-P(PEGMA-r-MMA)大分子聚集体。该大分子聚集体的存在导致铸膜液微观构象调整、表面张力下降、凝胶速率加快和粘度增加；讨论了反应原液的含量和凝胶浴组成对PVDF膜结构和性能的影响。结果表明,PVDF-P(PEGMA-r-MMA)大分子聚集体调控了PVDF-P(PEGMA-r-MMA)共混超滤膜的结构,且共混膜有效孔径μ分布变窄；截留分子量(MWCO)和牛血清(BSA)恢复通量均随P(PEGMA-r-MMA)两亲共聚物含量的增加而增加。
随后,为了克服简单共混法形成的大尺寸PVDF-P(PEGMA-r-MMA)大分子聚集体(粒径尺寸：100～200nm)对PVDF膜调控结构和性能改善的限制,采用原位自由基聚合反应法制备出小尺寸(粒径尺寸：0-10nm)、窄分布的PVDF-P(PEGMA-r-MMA)大分子聚集体,以强化P(PEGMA-r-MMA)两亲共聚物对PVDF膜结构的调控,并讨论了PVDF-P(PEGMA-r-MMA)大分子聚集体对PVDF膜机械强度和抗污染性能的影响。DLS和扫描电镜(SEM)结果表明,原位自由基聚合反应后的PVDF-TEP-DMAc-PEGMA-MMA铸膜液体系中形成了窄分布、小尺寸的大分子聚集体；铸膜液表面张力下降、凝胶速率加快及粘度增加；制得的PVDF膜除具有窄分布的有效孔径μ和截留分子量(MWCO)外,其μ和MWCO均随铸膜液中添加的单体混合物含量的增加而增加。结果表明,原位自由基聚合反应法增强了PVDF膜的机械强度(其良好的断裂强度、断裂伸长率和杨氏模量分别为：8.8MPa、343%和229MPa)、改善了PVDF膜正反面的亲水性；PVDF膜的主要结晶晶型是α-β杂化晶(以β晶型为主),且随铸膜液中单体混合物含量的增加,膜的结晶度从56.1%增加至81.4%。原位自由基聚合反应后的PEGMA、MMA单体更好地调控了PVDF膜结构：构成膜海绵状断面的聚合物纳米晶粒由条纹状转化为球状。
最后,在前文研究的基础上,采用实验室自制的活性更高的聚二甲基丙烯酸四氢呋喃酯(PTMGDA)代替MMA与PEGMA进行原位自由基聚合反应,制备PVDF中空纤维超滤膜。讨论了原位自由基聚合反应后的PVDF-TEP-DMAc-PTMGDA-PEGMA-PVP铸膜液体系的物理-化学性能变化,及形成的PVDF-P(PTMGDA-r-PEGMA)-PVP大分子聚集体对PVDF中空纤维膜结构调控及其渗透性能、机械强度和抗BSA污染性能的影响。结果表明,固定铸膜液中PTMGDA、PEGMA单体混合物含量不变,随着铸膜液中聚乙烯吡咯烷酮(PVP)的含量从1.0wt.%增加至3.0wt.%,PVDF中空纤维膜的海绵状断面结构中出现圆形孔道,而且构成海绵状结构的纳米聚合物晶粒的厚度增加、排列疏松,且膜的纯水通量从15.7L.m-1.h-1增加至60.2L.m-1.h-1,但PVDF膜的机械强度和对Dextran (40K和70K)的截留率变化不大；膜的接触角从78.8°降至65.2°,BSA通量恢复率(FRR)随PVP含量的增加而增加；原位自由基聚合反应后形成的P(PTMGDA-r-PEGMA)两亲共聚物与添加的PVP添加剂协同调控了PVDF中空纤维膜的结构、通量、亲水性和机械性能,并制得可应用于废水处理、生化分离等领域的PVDF中空纤维膜。
Ultrafiltration has been widely applied not only in the biological products, pharmaceutical products and food industry; but also used for blood, wastewater treatment and ultra pure water preparation. Because of its competitive mechanical properties, thermal and chemical stability, radiation resistance, etc. As one of the most popular materials for membranes preparation, polyvinylidene fluoride (PVDF) has earned lots of attention. However, PVDF membranes possess high hydrophilicity, which leads to poor wetting ability and prone to fouling, especially in the oil/water separation system, including protein or organism. This results in decreasing of performance properties, reducing the membrane life and increasing the operation cost. Thus, the fine configurations modulation of PVDF membranes with excellent hydrophilicity and high performance are always highly sought after. The self-assembled of surfactants with various molecular weights (Tween-80and amphiphilic copolymer) in organic solvents was utilized to tune the hydrophilicity, morphology and performances of PVDF membranes. Then, after optimization of preparation parameters of flat sheet PVDF membrane preparation, PVDF hollow fiber membranes possessed good permeability, hydrophilicity and excellent mechanical properties were successfuly fabricated. The results were as follows.
Firstly, PVDF membranes were fabricated by non-solvent induced phase separation (NIPS) process using Tween-80and H2O as mixture additive from both60℃and room-temperature (RT) casting solution. PVDF membranes revealed improved pure water flux (PWF), enlarged mechanical properties and well Bovine serum albumin (BSA) and Dextran rejection as a result of addition of H2O into the PVDF-DMAc-Tween-80system. The PWF of resultant PVDF was192L·m-2·h-1with0.1MPa operation pressure, and its rejection of BSA (MW67K) and Dextran (MW70K) were88.3%and83.8%, respectively. Its break strength, elongation at break and Young's modules were1.3MPa,42.2%and32.2MPa, respectively. The PWF increased to1.7times (prepared with60℃casting solution) and2.3times (prepared with ambient temperature casting solution) after addition of H2O into the casting solution. Besides, PVDF membranes'mechanical properties and dynamic contact angle increased as H2O concentration increasing. However, the rejection of BSA and Dextran of resultant PVDF membranes changed little as H2O concentration increasing. The improved performance was attributed to the existence of non-solvent, which was solubilized by the polar head groups of Tween-80reverse micelle to form the water pool. Furthermore, the interaction between polar head of surfactant and water provided a balance resistance to the interconnection between PVDF and hydrophobic chains of the surfactant, which enhanced the thermodynamics stability of casting solution.
Secondly, to obtain the target modulation path of Tween-80and H2O dopants, various compositions of coagulants and temperatures of casting solutions were utilized. PVDF membranes possessed interconnected bi-continuous structures with superior mechanical properties and fine hydrophilicity improvement were obtained from PVDF-DMAc-Tween-80-H2O system with60℃and ambient temperature casting solution, respectively. Tween-80-H2O mixtures were adopted as dope additive; water-ethanol (50:50, mass ratio) and ethanol were chosen as coagulants. The effects of process parameters in terms of variation contents of dope additives, casting solution temperatures and coagulant compositions on phase inversion process and performances of resultant PVDF membranes were investigated. Results showed that the compositions of coagulants modulated the sequence and the extent of liquid-liquid and liquid-solid demixing (crystallization), while the contents of dope additives and casting solution temperatures changed the precipitation rate of the casting solutions. During demixing process, water diffused from interior of Tween-80reverse micelles, resulting in the accelerated precipitation rate and surface segregation process of polar head groups of Tween-80. And the high temperature of casting solution contributed to the enhancing diffusion rate of liquid-liquid demixing on crystallization. The coagulant compositions changed the extent of liquid-liquid and solid-liquid demixing dynamic of casting solutions. Ethanol coagulant contributed to the crystallization of PVDF-DMAc-Tween-80-water system occurred prior to liquid-liquid demixing. This longer time-delay demixing process favored the formation of porous foliage type top-structures with fibrils or laths bi-continuous fine structure of membrane bulk, contributing to the increased flux and significant hydrophilicity improvement. While casting solutions in water-ethanol coagulant exhibited the shorter time-delay demixing process with both liquid-liquid demixing and crystallization, resulting in the formation of the fine structure in the form of the strings or stripes and limited the hydrophilic improvement. The predominant typical α and β type crystalline with crystallinity degree of59.1%in PVDF was attributed to the existence of dope additives, high temperature of casting solution and water-ethanol coagulant. This was consistent with the superior mechanical properties of corresponding PVDF membrane.
In order to avoid the high activity, soluble problem of Tween-80during PVDF membrane preparation and operating process, as well better modulation configuration of PVDF membranes, P(PEGMA-r-MMA) amphiphilic copolymer with Mn of66500g/mol and Mw of34200g/mol was synthesized via free radical polymerization choosing polyethylene glycol monomethyl ether methyl methacrylate (PEGMA) and methyl methacrylate (MMA) as reaction monomers, and its chemical structure and composition were characterized. And polyvinylidene fluoride (PVDF)-P(PEGMA-r-MMA) blend membranes were fabricated from water and ethanol coagulants via simplified blend method by directly blending PVDF and P(PEGMA-r-MMA) amphiphilic copolymer solution (including the reaction mixture) to form casting solution. The formation of the supramolecular aggregates of PVDF-P(PEGMA-r-MMA) in PVDF solution containing the copolymer were confirmed by dynamic light scattering (DLS) and scanning electron microscopy (SEM). This contributed to the micro-structure adjustment of PVDF solution and resulted in its decreasing surface tension, accelerating precipitation rate and increasing viscosity with trivial strain thinning behavior. Furthermore, the effects of the variations in dopant contents and coagulant compositions on the performances of those blend membranes were investigated. All PVDF-P(PEGMA-r-MMA) blend membranes possessed narrow distribution mean effective pore size (p.), molecular weight cut off (MWCO), improved recovery water flux after filtration experiments of BSA and tuned configurations. Compared with the instantaneous demixing process in water coagulant, the delayed demixing process in ethanol favored the pore-forming and surface segregated of the polar head group of the copolymer, which induced the increasing μ, MWCO, tunable morphologies and hydrophilicity improvement.
The results of simpilified blend method showed that the formation of the large-sized nanoparticulate aggregates (size:100～200nm) of PVDF-P(PEGMA-r-MMA) in the casting solution limited the function of the P(PEGMA-r-PEGMA) amphiphilic copolymer with respect to pore-forming and morphology modulation of the resultant membranes. Then the in situ free radical polymerization was creatively designed to obtain narrow distribution PVDF-P(PEGMA-r-MMA) supramolecular aggregates with small size and enhance better modulation configration of P(PEGMA-r-MMA); PVDF membranes with superior mechanical behaviors and enhanced antifouling properties was proven to be successfully fabricated. The DLS and SEM results verified the formation of supramolecular polymer-copolymer aggregates with small size (size:0-10nm). The narrow distribution of the supramolecular aggregates explained the decreasing surface tension, increasing viscosity with trivial strain thinning behavior and accelerating precipitation rate of the PVDF casting solution. The resultant PVDF membranes possessed narrowly distributed pore size and MWCO of the final filtration properties, which were attributed to the aggregates; additionally, their corresponding μ and MWCO increased, including the crystallinity of the a and β phase (largely in the β phase form) varied from56.1%to84.1%with increasing concentration of the monomers via in situ polymerization. Furthermore, in situ polymerization not only enlarged the recovery water flux after filtration experiments with BSA but also improved the hydrophilicity of both the top-surface and the bottom-surface of the PVDF membranes. Additionally, in situ polymerization modulated the configurations of PVDF membrane, varying from stripe-shaped grains to agglomerates of globule (with one of the globules bearing on the surface of another). The tunable morphologies, combined with the progressive enhanced crystallinity of the a and P phase were used to interpret the superior mechanical properties (Its break strength, elongation at break and Young's modules were8.8MPa,343%and229MPa, respectively) of the resulting PVDF membranes.
Finally, basic previous study, and choosing polytetrahydrofuran dimethacrylate ester (PTMGDA) that synthesied by our own lab with high reaction activity as reaction monomers instead of MMA, and reacted with PEGMA to synthesis P(PTMGDA-r-PEGMA) amphiphilic copolymer. PVDF hollow fiber UF membranes were prepared from the PVDF-TEP-DMAc-PTMGDA-PEGMA-PVP casting solution system after in situ polymerization. Combined with basic physical-chemical properties of the casting solution caused by the formation of PVDF-P(PTMGDA-r-PEGMA)-PVP supramoleculat aggregates, the configuration modulation, permeability, mechanical properties and antifouling BSA of resulant PVDF hollow fiber membranes were investigated. Results indicated that the round role appreared in the sponge-like cross-section of PVDF hollow fiber membranes, and the nanograins that constrcuted membrane bulk became widen and loose-packing as PVP concentration increasing. Besides, the membranes'pure water flux increased from15.7L.m-1.h-1to60.2L.m-1.h-1, and their mechanical properties and the rejection of Dextran (40K and70K) changed little. This showed that the synergy effects of PVP and the P(PTMGDA-r-PEGMA) amphiphilic copolymer formed via in situ polymerization on configration modulation and tuned performances of PVDF hollow fiber membranes. And the newly developed hydrophilicity PVDF hollow fiber membranes with superior mechanical properties and low-fouling of BSA are anticipated to be suitable not only for wastewater treatment, but also for bio-separation.
引文
[I]Koltuiewicz A B, Drioli E. Membranes in Clean Technologies[M]. Wiley-VCH Verlag Gmbh & Co. KGaA:Deutsche Nationalbibligrafie,2008
[2]Guillen G R, Pan Y, Li M, et al. Preparation and Characterization of Membranes Formed by Nonsolvent Induced Phase Separation:A Review[J]. Industrial & Engineering Chemistry Research.2011,50(7):3798-3817
[3]Nunes S P, Peinemann K V. Membrane Technology in the Chemical Industry[M]. WILEY-VCH Verlag GmbH:Weinheim,2001;
[4]Komaki Y. Growth of fine holes by the chemical etching of fission tracks in polyvinylidene fluoride[J]. Nuclear Tracks.1979,3(1-2):33-44
[5]Benzingera W D, Parekha B S, Eichelbergera J L. High Temperature Ultrafiltration With Kynar(?) Poly(Vinylidene Fluoride) Membranes[J]. Separation Science and Technology.1980, 15(4):1193-1204
[6]Lin D J, Beltsios K, Young T H, et al. Strong effect of precursor preparation on the morphology of semicrystalline phase inversion poly(vinylidene fluoride) membranes[J]. Journal of Membrane Science.2006,274(1-2):64-72
[7]Jang H J, Kim J H, Park M S, et al. Operational Performances of State of the Art PVDF Hollow Fiber Membrane Based on the Stretching Technology for Surface Water Treatment[J]. Procedia Engineering.2012,44:1363-1365
[8]Li N, Xiao C, Mei S, et al. The multi-pore-structure of polymer-silicon hollow fiber membranes fabricated via thermally induced phase separation combining with stretching[J]. Desalination.2011,274(1-3):284-291
[9]Awanis Hashim N, Liu Y, Li K. Stability of PVDF hollow fibre membranes in sodium hydroxide aqueous solution[J]. Chemical Engineering Science.2011,66(8):1565-1575
[10]Cohen C, Tanny G B, Prager S. Diffusion-controlled formation of porous structures in ternary polymer systems[J]. Jouranl of Polymer Science, Part B:Polymer Physics.1979, 17(3):477-489
[11]Wijmans J G, Kant J, Mulder M H V, et al. Phase separation phenomena in solutions of polysulfone in mixtures of a solvent and a nonsolvent:relationship with membrane formation[J]. Polymer.1985,26(10):1539-1545
[12]Strathmann H, Kock K. Formation mechanism of phase inversion membranes[J]. Desalination.1977,21(3):241-255
[13]Han L F, Xu Z L, Cao Y, et al. Preparation, characterization and permeation property of Al2O3, Al2O3-SiO2 and Al2O3-kaolin hollow fiber membranes[J]. Journal of Membrane Science.2011,372(1-2):154-164
[14]Kim J, Van der Bruggen B. The use of nanoparticles in polymeric and ceramic membrane structures:Review of manufacturing procedures and performance improvement for water treatment[J]. Environmental Pollution.2010,158(7):2335-2349
[15]Ng L Y, Mohammad A W, Leo C P, et al. Polymeric membranes incorporated with metal/metal oxide nanoparticles:A comprehensive review[J]. Desalination.2013,308:15-33
[16 Grasselli M, Betz N. Making porous membranes by chemical etching of heavy-ion tracks in β-PVDF films[J]. Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms.2005,236(1-4):501-507
[17]Mazzei R, Bermudez G G, Fernandez A, et al. Grafting of PNIPAAm on PVDF submicroscopic tracks induced by the active sites remainders of the etching process[J]. Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms.2008,266(6):937-943
[18]Wang J Y, Liu F, Xu Z 1, et al. Theophylline molecular imprint composite membranes prepared from poly(vinylidene fluoride) (PVDF) substrate[J]. Chemical Engineering Science. 2010,65(10):3322-3330
[19]Meng S, Mansouri J, Ye Y, et al. Effect of templating agents on the properties and membrane distillation performance of TiO2-coated PVDF membranes [J]. Journal of Membrane Science.2014,450:48-59
[20]Chang H H, Yao L C, Lin D J, et al. Preparation of microporous poly(VDF-co-HFP) membranes by template-leaching method[J]. Separation and Purification Technology.2010, 72(2):156-166
[21 Wang Q, Wang X, Wang Z, et al. PVDF membranes with simultaneously enhanced permeability and selectivity by breaking the tradeoff effect via atomic layer deposition of TiO2[J]. Journal of Membrane Science.2013,442:57-64
[22]Daraei P, Madaeni S S, Salehi E, et al. Novel thin film composite membrane fabricated by mixed matrix nanoclay/chitosan on PVDF microfiltration support:Preparation, characterization and performance in dye removal[J]. Journal of Membrane Science.2013,436: 97-108
[23]Na H, Chen P, Wong S C, et al. Fabrication of PVDF/PVA microtubules by coaxial electrospinning[J]. Polymer.2012,53(13):2736-2743
[24]Na H, Liu X, Li J, et al. Formation of core/shell ultrafine fibers of PVDF/PC by electrospinning via introduction of PMMA or BTEAC[J]. Polymer.2009,50(26):6340-6349
[25]Chinnappan A, Kim H, Hwang I T. An efficient and recyclable PVDF-IL nanofiber composite for the reduction of functionalized carbonyl compounds[J]. Chemical Engineering Journal.2012,191:451-456
[26]Loeb S, Sourirajan S. Preparation of asymmetric Loeb-Sourirajan membranes [P]. United States,1973
[27]Cha B J, Yang J M. Preparation of poly(vinylidene fluoride) hollow fiber membranes for microfiltration using modified TIPS process[J]. Journal of Membrane Science.2007,291(1-2): 191-198
[28]Li X F, Wang Y G, Lu X L, et al. Morphology changes of polyvinylidene fluoride membrane under different phase separation mechanisms[J]. Journal of Membrane Science. 2008,320(1-2):477-482
[29]Strathmann H, Kock K, Amar P, et al. Formation mechanism of asymmetric membranes[J]. Desalination.1975,16(2):179-203
[30]Radovanovic P, Thiel S W, Hwang S T. Formation of asymmetric polysulfone membranes by immersion precipitation. Part I. Modelling mass transport during gelation[J]. Journal of Membrane Science.1992,65(3):213-229
[31]Matz R. The structure of cellulose acetate membranes 1. The development of porous structures in anisotropic membranes[J]. Desalination.1972,10(1):1-15
[32]Frommer M A, Lancet D. The Mechanism of Membrane Formation:Membrane Structures and Their Relation to Preparation Conditions[M]. Plenum Press:New York,1972
[33]Ray R J, Krantz W B, Sani R L. Linear stability theory model for finger formation in asymmetric membranes[J]. Journal of Membrane Science.1985,23(2):155-182
[34]Boom R M, Wienk I M, Vandenboomgaard T, et al. Microstructures in phase inversion membranes. Part 2. The role of a polymeric additive [J]. Journal of Membrane Science.1992, 73(2-3):277-292
[35]Smolders C A, Reuvers A J, Boom R M, et al. Microstructures in phase-inversion membranes.1. Formation of macrovoids[J]. Journal of Membrane Science.1992,73(2): 259-275
[36]Radovanovic P, Thiel S W, Hwang S T. Formation of asymmetric polysulfone membranes by immersion precipitation. Part I. Modelling mass transport during gelation[J]. Journal of Membrane Science.1992,65(3):213-229
[37]Mosqueda-Jimenez D B, Narbaitz R M, Matsuura T, et al. Influence of processing conditions on the properties of ultrafiltration membranes[J]. Journal of Membrane Science. 2004,231(1-2):209-224
[38]Bottino A, Capannelli G, Munari S, et al. Solubility parameters of poly(vinylidene fluoride)[J]. Journal of Polymer Science Part B:Polymer Physics.1988,26(4):785-794
[39]Bottino A, Roda G C, Capannelli G, et al. The formation of microporous polyvinylidene difluoride membranes by phase separation[J]. Journal of Membrane Science.1991,57(1): 1-20
[40]Munari S, Bottino A, Capannelli G. Casting and performance of polyvinylidene fluoride based membranes[J]. Journal of Membrane Science.1983,16:181-193
[41]Shih H C, Yeh Y S, Yasuda H. Morphology of microporous poly(vinylidene fluoride) membranes studied by gas permeation and scanning electron microscopy [J]. Journal of Membrane Science.1990,50(3):299-317
[42]Yeow M L, Liu Y T, Li K. Morphological Study of Poly(vinylidene fluoride) Asymmetric Membranes:Effects of the Solvent, Additive, and Dope Temperature [J]. Journal of Applied Polymer Science.2004,92:1782-1789
[43]Li Q, Xu Z L, Yu L Y. Effects of mixed solvents and PVDF types on performances of PVDF microporous membranes[J], Journal of Applied Polymer Science.2010,115(4): 2277-2287
[44]Chen G E, Wu W Z, Zhang P Y, et al. Influence of Residence Time on Performances of PVDF Membranes Prepared Via Free Radical Polymerization[J]. Journal of Applied Polymer Science.2013,131(6):39987-39998
[45]Deshmukh S P, Li K. Effect of ethanol composition in water coagulation bath on morphology of PVDF hollow fibre membranes[J]. Journal of Membrane Science.1998,150: 75-85
[46]Wienk I M, Boom R M, Beerlage M A M, et al. Recent advances in the formation of phase inversion membranes made from amorphous or semi-crystalline polymers[J]. Journal of Membrane Science.1996,113:361-371
[47]Zhang P Y, Yang H, Xu Z L. Preparation of Polyvinylidene Fluoride (PVDF) Membranes via Nonsolvent Induced Phase Separation Process using a Tween 80 and H2O Mixture As an Additive[J]. Industrial & Engineering Chemistry Research.2012,51(11):4388-4396
[48]Zhang P Y, Xu Z L, Yang H, et al. Preparation and characterization of PVDF-P(PEGMA-r-MMA) ultrafiltration blend membranes via simplified blend method[J]. Desalination.2013,319:47-59
[49]Young T H, Cheng L P, Lin D J, et al. Mechanisms of PVDF membrane formation by immersion-precipitation in soft (1-octanol) and harsh (water) nonsolvents[J]. Polymer.1999, 40:5315-5323
[50]Machado P S T, Habert A C, Borges C P. Membrane formation mechanism based on precipitation kinetics and membrane morphology:at and hollow fiber polysulfone membranes[J]. Journal of Membrane Science.1999,155(171-183):
[51]Khayet M. Surface Modification of Polyvinylidene Fluoride Pervaporation Membranes[J]. AIChE Journal.2002,48(12):2833-2843
[52]Wang D, Li K, Teo W K. Preparation and characterization of polyvinylidene fluoride (PVDF) hollow fiber membranes[J]. Journal of Membrane Science.1999,163(2):211-220
[53]Ghosh A K, Jeong B-H, Huang X, et al. Impacts of reaction and curing conditions on polyamide composite reverse osmosis membrane properties[J]. Journal of Membrane Science. 2008,311(1-2):34-45
[54]Chun K Y, Jang S H, Kim H S, et al. Effects of solvent on the pore formation in asymmetric 6FDA-4,40 ODA polyimide membrane:Terms of thermodynamics, precipitation kinetics, and physical factors[J]. Journal of Membrane Science.2000,169:197-214
[55]Tomaszewska M. Preparation and properties of flat-sheet membranes from poly(vinylidene fluoride) for membrane distillation[J]. Desalination.1996,104:1-11
[56]Yeow M L, Liu Y T, Li K. Morphological Study of Poly(vinylidene fluoride) Asymmetric Membranes:Effects of the Solvent, Additive, and Dope Temperature[J]. Journal of Applied Polymer Science.2004,92:1782-1789
[57]Cheng L P. Effect of Temperature on the Formation of Microporous PVDF Membranes by Precipitation from 1-Octanol/DMF/PVDF and Water/DMF/PVDF Systems[J]. Macromolecules.1999,32:6668-6674
[58]Wang X, Zhang L, Sun D, et al. Effect of coagulation bath temperature on formation mechanism of poly(vinylidene fluoride) membrane[J]. Journal of Applied Polymer Science. 2008,110(3):1656-1663
[59]Ying L, Zhai G, Winata A Y, et al. pH effect of coagulation bath on the characteristics of poly(acrylic acid)-grafted and poly(4-vinylpyridine)-grafted poly(vinylidene fluoride) micro filtration membranes[J]. Journal of Colloid and Interface Science.2003,265(2): 396-403
[60]Buonomenna M, Macchi P, Davoli M, et al. Poly(vinylidene fluoride) membranes by phase inversion:the role the casting and coagulation conditions play in their morphology, crystalline structure and properties[J]. European Polymer Journal.2007,43(4):1557-1572
[61]Li Q, Xu Z L, Liu M. Preparation and characterization of PVDF microporous membrane with highly hydrophobic surface[J]. Polymers for Advanced Technologies.2011,22(5): 520-531
[62]J. S T, Roxbury M W. Process for preparing microporous polyvinylidene fluoride membranes[P]. US:4775703 A,1988
[63]Zhang P Y, Wang Y L, Xu Z L, et al. Preparation of poly (vinyl butyral) hollow fiber ultrafiltration membrane via wet-spinning method using PVP as additive[J]. Desalination. 2011,278(1-3):186-193
[64]Yoo S H, Kim J H, Jho J Y, et al. Influence of the addition of PVP on the morphology of asymmetric polyimide phase inversion membranes:effect of PVP molecular weight[J]. Journal of Membrane Science.2004,236(1-2):203-207
[65]Wongchitphimon S, Wang R, Jiraratananon R, et al. Effect of polyethylene glycol (PEG) as an additive on the fabrication of polyvinylidene fluoride-co-hexafluropropylene (PVDF-HFP) asymmetric microporous hollow fiber membranes[J]. Journal of Membrane Science.2011,369(1-2):329-338
[66]Naim R, Ismail A F, Mansourizadeh A. Effect of non-solvent additives on the structure and performance of PVDF hollow fiber membrane contactor for CO2 stripping[J]. Journal of Membrane Science.2012,423-424:503-513
[67]Mansourizadeh A, Ismail A F. Influence of membrane morphology on characteristics of porous hydrophobic PVDF hollow fiber contactors for CO2 stripping from water[J]. Desalination.2012,287:220-227
[68]Liu J, Xu Z, Li X, et al. An improved process to prepare high separation performance PA/PVDF hollow fiber composite nanofiltration membranes[J]. Separation and Purification Technology.2007,58(1):53-60
[69]Rahbari-Sisakht M, Ismail A F, Rana D, et al. Effect of SMM concentration on morphology and performance of surface modified PVDF hollow fiber membrane contactor for CO2 absorption[J]. Separation and Purification Technology.2013,116:67-72
[70]Rahimpour A, Madaeni S, Mansourpanah Y. The effect of anionic, non-ionic and cationic surfactants on morphology and performance of polyethersulfone ultrafiltration membranes for milk concentration[J]. Journal of Membrane Science.2007,296(1-2):110-121
[71]Saedi S, Madaeni S S, Arabi Shamsabadi A, et al. The effect of surfactants on the structure and performance of PES membrane for separation of carbon dioxide from methane[J]. Separation and Purification Technology.2012,99:104-119
[72]Wang D, Li K, Teo W K. Porous PVDF asymmetric hollow fiber membranes prepared with the use of small molecular additives[J]. Journal of Membrane Science.2000,178:13-23
[73]Cui Z, Xu Y, Zhu L, et al. Preparation of PVDF/PEO-PPO-PEO blend microporous membranes for lithium ion batteries via thermally induced phase separation process [J]. Journal of Membrane Science.2008,325(2):957-963
[74]Zhao C, Xu X, Chen J, et al. Effect of graphene oxide concentration on the morphologies and antifouling properties of PVDF ultrafiltration membranes [J]. Journal of Environmental Chemical Engineering.2013,1(3):349-354
[75]Chinnappan A, Kang H C, Kim H. Preparation of PVDF nanofiber composites for hydrogen generation from sodium borohydride[J]. Energy.2011,36(2):755-759
[76]Fontananova E, Jansen J C, Cristiano A, et al. Effect of additives in the casting solution on the formation of PVDF membranes[J]. Desalination.2006,192(1-3):190-197
[77]Kong J F, Li K. Preparation of PVDF Hollow-Fiber Membranes via Immersion Precipitation[J]. Journal of Applied Polymer Science.2001,81:1643-1653
[78]Yeow M L, Liu Y T, Li K. Preparation of porous PVDF hollow fibre membrane via a phase inversion method using lithium perchlorate (LiC104) as an additive[J]. Journal of Membrane Science.2005,258(1-2):16-22
[79]Khayet M, Matsuura T. Preparation and Characterization of Polyvinylidene Fluoride Membranes for Membrane Distillation[J]. Industrial & Engineering Chemistry Research. 2001,40:5710-5718
[80]Uragami T, Naito Y, Sugihara M. Studies on synthesis and permeability of special polymer membranes[J]. Polymer Bulletin.1981,4(10):617-622
[81]Khayet M, Feng C Y, Khulbe K C, et al. Study on the effect of a non-solvent additive on the morphology and performance of ultrafiltration hollow-fiber membranes[J]. Desalination. 2002,148(1-3):321-327
[82]Ahmad A L, Ideris N, Ooi B S, et al. Morphology and polymorph study of a polyvinylidene fluoride (PVDF) membrane for protein binding:Effect of the dissolving temperature[J]. Desalination.2011,278(1-3):318-324
[83]Kuo C Y, Lin H N, Tsai H A, et al. Fabrication of a high hydrophobic PVDF membrane via nonsolvent induced phase separation[J]. Desalination.2008,233(1-3):40-47
[84]Loh C H, Wang R, Shi L, et al. Fabrication of high performance polyethersulfone UF hollow fiber membranes using amphiphilic Pluronic block copolymers as pore-forming additives[J]. Journal of Membrane Science.2011,380(1-2):114-123
[85]Liu F, Hashim N A, Liu Y, et al. Progress in the production and modification of PVDF membranes[J]. Journal of Membrane Science.2011,375(1-2):1-27
[86]Barona G N B, Cha B J, Jung B. Negatively charged poly(vinylidene fluoride) microfiltration membranes by sulfonation[J]. Journal of Membrane Science.2007,290(1-2): 46-54
[87]Du J R, Peldszus S, Huck P M, et al. Modification of poly(vinylidene fluoride) ultrafiltration membranes with poly(vinyl alcohol) for fouling control in drinking water treatment[J]. Water Research.2009,43(18):4559-4568
[88]Xu Z, Li L, Wu F, et al. The application of the modified PVDF ultrafiltration membranes in further purification of Ginkgo biloba extraction[J]. Journal of Membrane Science.2005, 255(1-2):125-131
[89]Boributh S, Chanachai A, Jiraratananon R. Modification of PVDF membrane by chitosan solution for reducing protein fouling[J]. Journal of Membrane Science.2009,342(1-2): 97-104
[90]Kato K, Uchid E, Kang E T, et al. Polymer surface with graft chains[J]. Progress in Polymer Science.2003,28(2):209-259
[91]Hilal N, Kochkodan V, Khatib L A, et al. Surface modified polymeric membranes to reduce (bio)fouling:a microbiological study using E. coli[J]. Desalination.2004, 167(293-300):
[92]Botelho G, Silva M M, Goncalves A M, et al. Performance of electroactive poly(vinylidene fluoride) against UV radiation[J]. Polymer Testing.2008,27(7):818-822
[93]Hilal N, Khatib L A, Zoubi H A, et al. Atomic force microscopy study of membranes modified by surface grafting of cationic polyelectrolyte[J]. Desalination.2005,184(1-3): 45-55
[94]Rahimpour A, Madaeni S S, Zereshki S, et al. Preparation and characterization of modified nano-porous PVDF membrane with high antifouling property using UV photo-grafting[J]. Applied Surface Science.2009,255(16):7455-7461
[95]Zhang M, Nguyen Q T, Ping Z. Hydrophilic modification of poly (vinylidene fluoride) microporous membrane[J]. Journal of Membrane Science.2009,327(1-2):78-86
[96]Kaur S, Ma Z, Gopal R, et al. Plasma-induced immobilization of poly(ethylene glycol) onto poly(vinylidene fluoride) microporous membrane[J]. Langmuir.2007,23(26): 13085-13092
[97]Chan C M, Ko T M. Polymer surface modification by plasmas and photons[J]. Surface Science Reports.1996,24:1-54
[98]Wang P, Tan K L, Kang E T, et al. Plasma-induced immobilization of poly(ethylene glycol) onto poly(vinylidene fluoride) microporous membrane[J]. Journal of Membrane Science.2002,195:103-114
[99]Buonomenna M G, Lopez L C, Favia P, et al. New PVDF membranes:The effect of plasma surface modification on retention in nanofiltration of aqueous solution containing organic compounds[J]. Water Research.2007,41(19):4309-4316
[100]Chen Y, Ying L, Yu W, et al. Poly(vinylidene fluoride) with Grafted Poly(ethylene glycol) Side Chains Poly(ethylene glycol) Side Chains via the RAFT-Mediated Process and Pore Size Control of the Copolymer Membranes[J]. Macromolecules.2003,36:9451-9457
[101]Wang P, Tan K L, Kang E T, et al. Synthesis, characterization and anti-fouling properties of poly(ethylene glycol) grafted poly(vinylidene fluoride) copolymer membranes[J]. Journal of Materials Chemistry.2001,11(3):783-789
[102]Liu F, Du C H, Zhu B K, et al. Surface immobilization of polymer brushes onto porous poly(vinylidene fluoride) membrane by electron beam to improve the hydrophilicity and fouling resistance[J]. Polymer.2007,48(10):2910-2918
[103]Moad G, Rizzardo E, Thang S H. Radical addition-fragmentation chemistry in polymer synthesis[J]. Polymer.2008,49(5):1079-1131
[104]Chiefari J, Chong Y K, Ercole F, et al. Living free-radical polymerization by reversible addition-fragmentation chain transfer:the RAFT process[J]. Macromolecules.1998, 31(16):5559-5562
[105]Hester J F, Mayes A M. Design and performance of foul-resistant poly(vinylidene fluoride) membranes prepared in a single-step by surface segregation[J]. Journal of Membrane Science.2002,202:119-135
[106]Akthakul A, Salinaro R F, Mayes A M. Antifouling Polymer Membranes with Subnanometer Size Selectivity [J]. Macromolecules.2004,37:7663-7668
[107]Matyjaszewski K, Xia J. Atom transfer radical polymerization[J]. Chemical Reviews. 2001,101(9):2921-2990
[108]Cunningham M F. Controlled/living radical polymerization in aqueous dispersed systems[J]. Progress in Polymer Science.2008,33(4):365-398
[109]Singh N, Husson S M, Zdyrko B, et al. Surface modification of microporous PVDF membranes by ATRP[J]. Journal of Membrane Science.2005,262(1-2):81-90
[110]Liu D, Chen Y, Zhang N, et al. Controlled grafting of polymer brushes on poly(vinylidene fluoride) films by surface-initiated atom transfer radical polymerization[J]. Journal of Applied Polymer Science.2006,101(6):3704-3712
[111]Zhao Y H, Qian Y L, Pang D X, et al. Porous membranes modified by hyperbranched polymers Ⅱ. Effect of the arm length of amphiphilic hyperbranched-star polymers on the hydrophilicity and protein resistance of poly(vinylidene fluoride) membranes[J]. Journal of Membrane Science.2007,304(1-2):138-147
[112]Wei Y, Chu H Q, Dong B Z, et al. Effect of TiO2 nanowire addition on PVDF ultrafiltration membrane performance[J]. Desalination.2011,272(1-3):90-97
[113]Li J H, Li M Z, Miao J, et al. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive[J]. Applied Surface Science.2012, 258(17):6398-6405
[114]Chang Y, Ko C Y, Shih Y J, et al. Surface grafting control of PEGylated poly(vinylidene fluoride) antifouling membrane via surface-initiated radical graft copolymerization[J]. J. Membr. Sci.2009,345(1-2):160-169
[115]Hester J F, Banerjee P, Won Y Y, et al. ATRP of Amphiphilic Graft Copolymers Based on PVDF and Their Use as Membrane Additives[J]. Macromolecules.2002,35(20): 7652-7661
[116]Ying L, Kang E T, Neoh K G. Covalent immobilization of glucose oxidase on microporous membranes prepared from poly(vinylidene fluoride) with grafted poly(acrylic acid) side chains[J]. Journal of Membrane Science.2002,208:361-374
[117]Ying L, Kang E T, Neoh K G, et al. Drug permeation through temperature-sensitive membranes prepared from poly(vinylidene fluoride) with grafted poly(N-isopropylacrylamide) chains[J]. Journal of Membrane Science.2004,243:253-262
[118]Sui Y, Gao X, Wang Z, et al. Antifouling and antibacterial improvement of surface-functionalized poly(vinylidene fluoride) membrane prepared via dihydroxyphenylalanine-initiated atom transfer radical graft polymerizations [J]. Journal of Membrane Science.2012,394-395:107-119
[119]Chen Y, Liu D, Deng Q, et al. Atom transfer radical polymerization directly from poly(vinylidene fluoride):Surface and antifouling properties[J]. Journal of Polymer Science Part A:Polymer Chemistry.2006,44(11):3434-3443
[120]Li M Z, Li J H, Shao X S, et al. Grafting zwitterionic brush on the surface of PVDF membrane using physisorbed free radical grafting technique[J]. Journal of Membrane Science. 2012,405-406:141-148
[121]Chen Y, Deng Q, Xiao J, et al. Controlled grafting from poly(vinylidene fluoride) microfiltration membranes via reverse atom transfer radical polymerization and antifouling properties[J]. Polymer.2007,48(26):7604-7613
[122]Chen Y, Sun W, Deng Q, et al. Controlled grafting from poly(vinylidene fluoride) films by surface-initiated reversible addition-fragmentation chain transfer polymerization[J]. Journal of polymer science. Part A, Polymer Chemistry.2006,44(9):3071-3082
[123]Kim J H, Min B R, Won J, et al. Phase behavior and mechanism of membrane formation for polyimide/DMSO/water system[J]. Joural of Membrane Science 2001,187: 47-55
[124]Ochoa N. Effect of hydrophilicity on fouling of an emulsified oil wastewater with PVDF/PMMA membranes[J]. Journal of Membrane Science.2003,226(1-2):203-211
[125]Nunes S P, Peinemann K V. Ultrafiltration membranes from PVDF/PMMA blends[J]. Journal of Membrane Science.1992,73(1):25-35
[126]Masuelli M, Marchese J, Ochoa N A. SPC/PVDF membranes for emulsified oily wastewater treatment[J]. Journal of Membrane Science.2009,326(2):688-693
[127]Li N, Xiao C, An S, et al. Preparation and properties of PVDF/PVA hollow fiber membranes[J]. Desalination.2010,250(2):530-537
[128]Basilio N, Garcia-Rio L, Martin-Pastor M. Calixarene-Based Surfactants:Evidence of Structural Reorganization upon Micellization[J]. Langmuir.2012,28(5):2404-2414
[129]Uragami T, Fujimoto M, Sugihara M. Studies on synthesis and permeabilities of special polymer membranes.28. Permeation characteristics and structure of interpolymer membranes from poly(vinylidene fluoride) and poly (styrene sulfonic acid)[J]. Desalination. 1980,34(3):311-323
[130]Hester J F, Banerjee P, Mayes A M. Preparation of Protein-Resistant Surfaces on Poly(vinylidene fluoride) Membranes via Surface Segregation[J]. Macromolecules.1999,32: 1643-1650
[131]Liu F, Xu Y Y, Zhu B K, et al. Preparation of hydrophilic and fouling resistant poly(vinylidene fluoride) hollow fiber membranes[J]. Journal of Membrane Science.2009, 345(1-2):331-339
[132]Hester J F, Olugebefola S C, Mayes A M. Preparation of pH-responsive polymer membranes by self-organization[J]. Journal of Membrane Science.2002,208:375-388
[133]Yuliwati E, Ismail A F. Effect of additives concentration on the surface properties and performance of PVDF ultrafiltration membranes for refinery produced wastewater treatment[J]. Desalination.2011,273(1):226-234
[134]Zhai G, Ying L, Kang E T, et al. Synthesis and characterization of poly(vinylidene fluoride) with grafted acid/base polymer side chains[J]. Macromolecules.2002,35(26): 9653-9656
[135]Ying L, Wang P, Kang E T, et al. Synthesis and characterization of poly(acrylic acid)-graft-poly(vinylidene fluoride) copolymers and pH sensitive membranes[J]. Macromolecules.2001,35(3):673-679
[136]Liu X, Neoh K G, Kang E T. Redox-sensitive microporous membranes prepared from poly(vinylidene fluoride) grafted with viologen-containing polymer side chains[J]. Macromolecules.2003,36(22):8361-8367
[137]Sui Y, Wang Z, Gao X, et al. Antifouling PVDF ultrafiltration membranes incorporating PVDF-g-PHEMA additive via atom transfer radical graft polymerizations[J]. Journal of Membrane Science.2012,413-414:38-47
[138]Zhao Y H, Zhu B K, Kong L, et al. Improving Hydrophilicity and Protein Resistance of Poly(vinylidene fluoride) Membranes by Blending with Amphiphilic Hyperbranched-Star Polymer[J]. Langmuir.2007,23:5779-5786
[139]Tahiri Alaoui O, Nguyen Q T, Mbareck C, et al. Elaboration and study of poly(vinylidene fluoride)-anatase TiO2 composite membranes in photocatalytic degradation of dyes[J]. Applied Catalysis A:General.2009,358(1):13-20
[140]Yu L Y, Xu Z L, Shen H M, et al. Preparation and characterization of PVDF SiO2 composite hollow fiber UF membrane by sol-gel method[J]. Journal of Membrane Science. 2009,337(1-2):257-265
[141]Bottino A, Capannelli G, Comite A. Preparation and characterization of novel porous PVDF-ZrO2 composite membranes[J]. Desalination.2002,146(1-3):35-40
[142]Ma J, Wang Z, Pan M, et al. A study on the multifunction of ferrous chloride in the formation of poly(vinylidene fluoride) ultrafiltration membranes[J]. Journal of Membrane Science.2009,341(1-2):214-224
[143]Dong C, He G, Li H, et al. Antifouling enhancement of poly(vinylidene fluoride) microfiltration membrane by adding Mg(OH)2 nanoparticles[J]. Journal of Membrane Science. 2012,387-388:40-47
[144]Manful J T, Grimm C C, Gayin J, et al. Effect of Variable Parboiling on Crystallinity of Rice Samples[J]. Cereal Chemistry.2008,85(1):92-95
[145]Yang Y, Yang D, Zhang S, et al. Preparation and characterization of poly(phthalazinone ether sulfone ketone) hollow fiber ultrafiltration membranes with excellent thermal stability [J]. Journal of Membrane Science.2006,280(1-2):957-968
[146]Lin D J, Beltsios K, Chang C L, et al. Fine Structure and Formation Mechanism of Particulate Phase-Inversion Poly(vinylidene fluoride) Membranes[J]. Jouranl of Polymer Science, Part B:Polymer Physics.2003:1578-1588
[147]Teshima K, Sugimura H, Inoue Y, et al. Ultra-Water-Repellent Poly(ethylene terephthalate) Substrates[J]. Langmuir.2003,19:10624-10627
[148]Allegrezza A E, Bellantoni E C. Porous membrane formed from interpenetrating polymer network having hydrophilic surface[P]. EP:0430082 B1,1996
[149]Koguma I, Nagoya F. Microporous hydrophilic membrane[P]. EP:1099468 A3,2002
[150]Mullette D, Muller J, Patel N. Membrane post treatment[P]. US:8262778 B2,2012
[151]Xu Y Y, Xu Z K. Polymer Membrane Material[M]. Chemical Industry Press:Beijing, 2005
[152]Wang S M, Wang Z, Zhang Y, et al. Experimental study of the control of pore sizes of porous membranes applying chemicals methods[J]. Desalination.2005,177(1-3):7-13
[153]Yoo S H, Kim J H, Jho J Y, et al. Influence of the addition of PVP on the morphology of asymmetric polyimide phase inversion membranes:effect of PVP molecular weight[J]. Journal of Membrane Science.2004,236(1-2):203-207
[154]Hou D, Wang J, Qu D, et al. Fabrication and characterization of hydrophobic PVDF hollow fiber membranes for desalination through direct contact membrane distillation[J]. Separation and Purification Technology.2009,69(1):78-86
[155]Mansourizadeh A, Ismail A F. Preparation and characterization of porous PVDF hollow fiber membranes for CO2 absorption:Effect of different non-solvent additives in the polymer dope[J]. International Journal of Greenhouse Gas Control.2011,5(4):640-648
[156]Yan L, Li Y S, Xiang C B. Preparation of poly(vinylidene fluoride)(pvdf) ultrafiltration membrane modified by nano-sized alumina (Al2O3) and its antifouling research[J]. Polymer.2005,46(18):7701-7706
[157]Elashmawi I S. Effect of LiCl filler on the structure and morphology of PVDF films[J]. Materials Chemistry and Physics.2008,107(1):96-100
[158]Mansourizadeh A, Ismail A F. Effect of LiCl concentration in the polymer dope on the structure and performance of hydrophobic PVDF hollow fiber membranes for CO2 absorption[J]. Chemical Engineering Journal.2010,165(3):980-988
[159]Amirilargani M, Saljoughi E, Mohammadi T. Effects of Tween 80 concentration as a surfactant additive on morphology and permeability of flat sheet polyethersulfone (PES) membranes[J]. Desalination.2009,249(2):837-842
[160]Amirilargani M, Saljoughi E, Mohammadi T. Improvement of permeation performance of polyethersulfone (PES) ultrafiltration membranes via addition of Tween-20[J]. Journal of Applied Polymer Science.2010,115(1):504-513
[161]Ghosh S. Comparative studies on brij reverse micelles prepared in benzene/surfactant/ethylammonium nitrate systems:Effect of head group size and polarity of the hydrocarbon chain[J]. Journal of Colloid and Interface Science.2011,360(2):672-680
[162]Sukitpaneenit P, Chung T S. Molecular elucidation of morphology and mechanical properties of PVDF hollow fiber membranes from aspects of phase inversion, crystallization and rheology[J]. Journal of Membrane Science.2009,340(1-2):192-205
[163]Tran Le T, Saveyn P, Hoa H D, et al. Determination of heat-induced effects on the particle size distribution of casein micelles by dynamic light scattering and nanoparticle tracking analysis[J]. International Dairy Journal.2008,18(12):1090-1096
[164]Santiago P S, Moura F, Moreira L M, et al. Dynamic Light Scattering and Optical Absorption Spectroscopy Study of pH and Temperature Stabilities of the Extracellular Hemoglobin of Glossoscolex paulistus[J]. Biophysical Journal.2008,94(6):2228-2240
[165]Falcone R D, Correa N M, Silber J J. On the Formation of New Reverse Micelles:A Comparative Study of Benzene/Surfactants/Ionic Liquids Systems Using UV-Visible Absorption Spectroscopy and Dynamic Light Scattering[J]. Langmuir.2009,25(18): 10426-10429
[166]Panu S, Chung T S. Molecular elucidation ofmorphology and mechanical properties of PVDF hollowfibermembranes fromaspects of phase inversion[J]. Journal of Membrane Science.2009,340:192-205
[167]Loos K, Bolker A, Zettl H, et al. Micellar Aggregates of Amylose-block-polystyrene Rod-Coil Block Copolymers in Water and THF[J]. Macromolecules.2005,38:873-879
[168]Lund A, Gustafsson C, Bertilsson H, et al. Enhancement of β phase crystals formation with the use of nanofillers in PVDF films and fibres[J]. Combustion Science and Technology.2011,71(2):222-229
[169]Sukitpaneenit P, Chung T S. Molecular elucidation of morphology and mechanical properties of PVDF hollow fiber membranes from aspects of phase inversion, crystallization and rheology[J]. Journal of Membrane Science.2009,340(1-2):192-205
[170]Strathmann H. Membrane Separation Processes:Current Relevance and Future Opportunities[J]. AIChE Journal.2001,47(5):1077-1087
[171]Awanis Hashim N, Liu F, Moghareh Abed M R, et al. Chemistry in spinning solutions:Surface modification of PVDF membranes during phase inversion[J]. Journal of Membrane Science.2012,415-416:399-411
[172]Field R, Hang S, Arnot T. The influence of surfactant on water flux through microfiltration membranes[J]. Journal of Membrane Science.1994,86(3):291-304
[173]Curcio E, Fontananova E, Profio G D, et al. Influence of the Structural Properties of Poly(vinylidene fluoride) Membranes on the Heterogeneous Nucleation Rate of Protein Crystals[J]. Journal of Physical Chemistry B.2006,110(25):12438-12445
[174]Yang Q, Kang X Z, Wei D Z, et al. Surface Modification of Polypropylene Microporous Membranes with a Novel Glycopolymer[J]. Chemistry of Materials.2005,17: 3050-3058
[175]Widanapathirana L, Zhao Y. Effects of Amphiphile Topology on the Aggregation of Oligocholates in Lipid Membranes:Macrocyclic versus Linear Amphiphiles[J]. Langmuir. 2012,28(21):8165-8173
[176]Fan X, Huang B, Wang G, et al. Synthesis of Amphiphilic Heteroeight-Shaped PolymerCyclic-[Poly(ethylene oxide)-b-polystyrene]2 via "Click" Chemistry [J]. Macromolecules.2012,45(9):3779-3786
[177]Yeow M L, Liu Y T, Li K. Isothermal Phase Diagrams and Phase-Inversion Behavior of Poly(vinylidene fluoride)/Solvents/Additives/Water Systems[J]. Journal of Applied Polymer Science.2003,90:2150-2155
[178]Hashim N A, Liu F, Li K. A simplified method for preparation of hydrophilic PVDF membranes from an amphiphilic graft copolymer[J]. Journal of Membrane Science.2009, 345(1-2):134-141
[179]Neugebauer D. Graft copolymers with poly(ethylene oxide) segments[J]. Polymer International.2007,56(12):1469-1498
[180]Zhou S, Sakamoto T, Wang J, et al. One-Dimensional Assembly of Silica Nanospheres:Effects of Nonionic Block Copolymers[J]. Langmuir.2012,28(37): 13181-13188
[181]Law S J, Britton M M. Sizing of Reverse Micelles in Microemulsions using NMR Measurements of Diffusion[J]. Langmuir.2012,28(32):11699-11706
[182]Letchford K, Burt H. A review of the formation and classification of amphiphilic block copolymer nanoparticulate structures:micelles, nanospheres, nanocapsules and polymersomes[J]. European Journal of Pharmaceutics and Biopharmaceutics.2007,65(3): 259-269
[183]Lu X, Gong S, Meng L, et al. Novel fluorescent amphiphilic block copolymers: Controllable morphologies and size by self-assembly [J]. European Polymer Journal.2007, 43(7):2891-2900
[184]Petkova R, Tcholakova S, Denkov N D. Foaming and Foam Stability for Mixed Polymer-Surfactant Solutions:Effects of Surfactant Type and Polymer Charge[J]. Langmuir. 2012,28(11):4996-5009
[185]Zhang P Y, Yang H, Xu Z L, et al. Characterization and preparation of poly(vinylidene fluoride) (PVDF) microporous membranes with interconnected bicontinuous structures via non-solvent induced phase separation (NIPS)[J]. Journal of Polymer Research. 2013,20(66-78):
[186]Shi F, Ma Y, Ma J, et al. Preparation and characterization of PVDF/TiO2 hybrid membranes with ionic liquid modified nano-TiO2 particles[J]. Journal of Membrane Science. 2013,427:259-269
[187]Ma H, Burger C, Hsiao B S, et al. Highly Permeable Polymer Membranes Containing Directed Channels for Water Purification[J]. ACS Macro Letters.2012,1(6):723-726
[188]Hussain H, Tan B H, Gudipati C S, et al. Micelle Formation of Amphiphilic Polystyrene-b-poly(N-vinylpyrrolidone) Diblock Copolymer in Methanol and Water-Methanol Binary Mixtures[J]. Langmuir.2009,25(10):5557-5564
[189]Zhang W, Shi L, An Y, et al. A Convenient Method of Tuning Amphiphilic Block Copolymer Micellar Morphology [J]. Macromolecules.2004,37:2551-2555
[190]Low YKA, Tan L Y, Tan L P, et al. Increasing Solvent Polarity and Addition of Salts Promote b-Phase Poly(vinylidene fluoride) Formation[J]. Journal of Applied Polymer Science. 2013,128(5):2902-2910
[191]Stropnik C, Kaiser V. Polymeric membranes preparation by wet phase separation: mechanisms and elementary processes[J]. Desalination.2002,145(1-2):1-10
[192]He X, Chen C, Jiang Z, et al. Computer simulation of formation of polymeric ultrafiltration membrane via immersion precipitation[J]. Journal of Membrane Science.2011, 371(1-2):108-116
[193]Zhou B, Powell A C. Phase field simulations of early stage structure formation during immersion precipitation of polymeric membranes in 2D and 3D[J]. Journal of Membrane Science.2006,268(2):150-164
[194]Lin D J, Chang C L, Huang F M, et al. Effect of salt additive on the formation of microporous polyvinylidene difluoride) membranes by phase inversion from LiClO4/Water/DMF/PVDF system[J]. Polymer.2003,44(2):413-422
[195]Elashmawi I S. Effect of LiCl filler on the structure and morphology of PVDF films[J]. Materials Chemistry and Physics 2008,107(1):96-100
[196]Zhang P Y, Xu Z L, Yang H, et al. Fabrication and characterization of PVDF membranes via an in situ free radical polymerization method[J]. Chemical Engineering Science.2013,97:296-308
[2]Guillen G R, Pan Y, Li M, et al. Preparation and Characterization of Membranes Formed by Nonsolvent Induced Phase Separation:A Review[J]. Industrial & Engineering Chemistry Research.2011,50(7):3798-3817
[3]Nunes S P, Peinemann K V. Membrane Technology in the Chemical Industry[M]. WILEY-VCH Verlag GmbH:Weinheim,2001;
[4]Komaki Y. Growth of fine holes by the chemical etching of fission tracks in polyvinylidene fluoride[J]. Nuclear Tracks.1979,3(1-2):33-44
[5]Benzingera W D, Parekha B S, Eichelbergera J L. High Temperature Ultrafiltration With Kynar(?) Poly(Vinylidene Fluoride) Membranes[J]. Separation Science and Technology.1980, 15(4):1193-1204
[6]Lin D J, Beltsios K, Young T H, et al. Strong effect of precursor preparation on the morphology of semicrystalline phase inversion poly(vinylidene fluoride) membranes[J]. Journal of Membrane Science.2006,274(1-2):64-72
[7]Jang H J, Kim J H, Park M S, et al. Operational Performances of State of the Art PVDF Hollow Fiber Membrane Based on the Stretching Technology for Surface Water Treatment[J]. Procedia Engineering.2012,44:1363-1365
[8]Li N, Xiao C, Mei S, et al. The multi-pore-structure of polymer-silicon hollow fiber membranes fabricated via thermally induced phase separation combining with stretching[J]. Desalination.2011,274(1-3):284-291
[9]Awanis Hashim N, Liu Y, Li K. Stability of PVDF hollow fibre membranes in sodium hydroxide aqueous solution[J]. Chemical Engineering Science.2011,66(8):1565-1575
[10]Cohen C, Tanny G B, Prager S. Diffusion-controlled formation of porous structures in ternary polymer systems[J]. Jouranl of Polymer Science, Part B:Polymer Physics.1979, 17(3):477-489
[11]Wijmans J G, Kant J, Mulder M H V, et al. Phase separation phenomena in solutions of polysulfone in mixtures of a solvent and a nonsolvent:relationship with membrane formation[J]. Polymer.1985,26(10):1539-1545
[12]Strathmann H, Kock K. Formation mechanism of phase inversion membranes[J]. Desalination.1977,21(3):241-255
[13]Han L F, Xu Z L, Cao Y, et al. Preparation, characterization and permeation property of Al2O3, Al2O3-SiO2 and Al2O3-kaolin hollow fiber membranes[J]. Journal of Membrane Science.2011,372(1-2):154-164
[14]Kim J, Van der Bruggen B. The use of nanoparticles in polymeric and ceramic membrane structures:Review of manufacturing procedures and performance improvement for water treatment[J]. Environmental Pollution.2010,158(7):2335-2349
[15]Ng L Y, Mohammad A W, Leo C P, et al. Polymeric membranes incorporated with metal/metal oxide nanoparticles:A comprehensive review[J]. Desalination.2013,308:15-33
[16 Grasselli M, Betz N. Making porous membranes by chemical etching of heavy-ion tracks in β-PVDF films[J]. Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms.2005,236(1-4):501-507
[17]Mazzei R, Bermudez G G, Fernandez A, et al. Grafting of PNIPAAm on PVDF submicroscopic tracks induced by the active sites remainders of the etching process[J]. Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms.2008,266(6):937-943
[18]Wang J Y, Liu F, Xu Z 1, et al. Theophylline molecular imprint composite membranes prepared from poly(vinylidene fluoride) (PVDF) substrate[J]. Chemical Engineering Science. 2010,65(10):3322-3330
[19]Meng S, Mansouri J, Ye Y, et al. Effect of templating agents on the properties and membrane distillation performance of TiO2-coated PVDF membranes [J]. Journal of Membrane Science.2014,450:48-59
[20]Chang H H, Yao L C, Lin D J, et al. Preparation of microporous poly(VDF-co-HFP) membranes by template-leaching method[J]. Separation and Purification Technology.2010, 72(2):156-166
[21 Wang Q, Wang X, Wang Z, et al. PVDF membranes with simultaneously enhanced permeability and selectivity by breaking the tradeoff effect via atomic layer deposition of TiO2[J]. Journal of Membrane Science.2013,442:57-64
[22]Daraei P, Madaeni S S, Salehi E, et al. Novel thin film composite membrane fabricated by mixed matrix nanoclay/chitosan on PVDF microfiltration support:Preparation, characterization and performance in dye removal[J]. Journal of Membrane Science.2013,436: 97-108
[23]Na H, Chen P, Wong S C, et al. Fabrication of PVDF/PVA microtubules by coaxial electrospinning[J]. Polymer.2012,53(13):2736-2743
[24]Na H, Liu X, Li J, et al. Formation of core/shell ultrafine fibers of PVDF/PC by electrospinning via introduction of PMMA or BTEAC[J]. Polymer.2009,50(26):6340-6349
[25]Chinnappan A, Kim H, Hwang I T. An efficient and recyclable PVDF-IL nanofiber composite for the reduction of functionalized carbonyl compounds[J]. Chemical Engineering Journal.2012,191:451-456
[26]Loeb S, Sourirajan S. Preparation of asymmetric Loeb-Sourirajan membranes [P]. United States,1973
[27]Cha B J, Yang J M. Preparation of poly(vinylidene fluoride) hollow fiber membranes for microfiltration using modified TIPS process[J]. Journal of Membrane Science.2007,291(1-2): 191-198
[28]Li X F, Wang Y G, Lu X L, et al. Morphology changes of polyvinylidene fluoride membrane under different phase separation mechanisms[J]. Journal of Membrane Science. 2008,320(1-2):477-482
[29]Strathmann H, Kock K, Amar P, et al. Formation mechanism of asymmetric membranes[J]. Desalination.1975,16(2):179-203
[30]Radovanovic P, Thiel S W, Hwang S T. Formation of asymmetric polysulfone membranes by immersion precipitation. Part I. Modelling mass transport during gelation[J]. Journal of Membrane Science.1992,65(3):213-229
[31]Matz R. The structure of cellulose acetate membranes 1. The development of porous structures in anisotropic membranes[J]. Desalination.1972,10(1):1-15
[32]Frommer M A, Lancet D. The Mechanism of Membrane Formation:Membrane Structures and Their Relation to Preparation Conditions[M]. Plenum Press:New York,1972
[33]Ray R J, Krantz W B, Sani R L. Linear stability theory model for finger formation in asymmetric membranes[J]. Journal of Membrane Science.1985,23(2):155-182
[34]Boom R M, Wienk I M, Vandenboomgaard T, et al. Microstructures in phase inversion membranes. Part 2. The role of a polymeric additive [J]. Journal of Membrane Science.1992, 73(2-3):277-292
[35]Smolders C A, Reuvers A J, Boom R M, et al. Microstructures in phase-inversion membranes.1. Formation of macrovoids[J]. Journal of Membrane Science.1992,73(2): 259-275
[36]Radovanovic P, Thiel S W, Hwang S T. Formation of asymmetric polysulfone membranes by immersion precipitation. Part I. Modelling mass transport during gelation[J]. Journal of Membrane Science.1992,65(3):213-229
[37]Mosqueda-Jimenez D B, Narbaitz R M, Matsuura T, et al. Influence of processing conditions on the properties of ultrafiltration membranes[J]. Journal of Membrane Science. 2004,231(1-2):209-224
[38]Bottino A, Capannelli G, Munari S, et al. Solubility parameters of poly(vinylidene fluoride)[J]. Journal of Polymer Science Part B:Polymer Physics.1988,26(4):785-794
[39]Bottino A, Roda G C, Capannelli G, et al. The formation of microporous polyvinylidene difluoride membranes by phase separation[J]. Journal of Membrane Science.1991,57(1): 1-20
[40]Munari S, Bottino A, Capannelli G. Casting and performance of polyvinylidene fluoride based membranes[J]. Journal of Membrane Science.1983,16:181-193
[41]Shih H C, Yeh Y S, Yasuda H. Morphology of microporous poly(vinylidene fluoride) membranes studied by gas permeation and scanning electron microscopy [J]. Journal of Membrane Science.1990,50(3):299-317
[42]Yeow M L, Liu Y T, Li K. Morphological Study of Poly(vinylidene fluoride) Asymmetric Membranes:Effects of the Solvent, Additive, and Dope Temperature [J]. Journal of Applied Polymer Science.2004,92:1782-1789
[43]Li Q, Xu Z L, Yu L Y. Effects of mixed solvents and PVDF types on performances of PVDF microporous membranes[J], Journal of Applied Polymer Science.2010,115(4): 2277-2287
[44]Chen G E, Wu W Z, Zhang P Y, et al. Influence of Residence Time on Performances of PVDF Membranes Prepared Via Free Radical Polymerization[J]. Journal of Applied Polymer Science.2013,131(6):39987-39998
[45]Deshmukh S P, Li K. Effect of ethanol composition in water coagulation bath on morphology of PVDF hollow fibre membranes[J]. Journal of Membrane Science.1998,150: 75-85
[46]Wienk I M, Boom R M, Beerlage M A M, et al. Recent advances in the formation of phase inversion membranes made from amorphous or semi-crystalline polymers[J]. Journal of Membrane Science.1996,113:361-371
[47]Zhang P Y, Yang H, Xu Z L. Preparation of Polyvinylidene Fluoride (PVDF) Membranes via Nonsolvent Induced Phase Separation Process using a Tween 80 and H2O Mixture As an Additive[J]. Industrial & Engineering Chemistry Research.2012,51(11):4388-4396
[48]Zhang P Y, Xu Z L, Yang H, et al. Preparation and characterization of PVDF-P(PEGMA-r-MMA) ultrafiltration blend membranes via simplified blend method[J]. Desalination.2013,319:47-59
[49]Young T H, Cheng L P, Lin D J, et al. Mechanisms of PVDF membrane formation by immersion-precipitation in soft (1-octanol) and harsh (water) nonsolvents[J]. Polymer.1999, 40:5315-5323
[50]Machado P S T, Habert A C, Borges C P. Membrane formation mechanism based on precipitation kinetics and membrane morphology:at and hollow fiber polysulfone membranes[J]. Journal of Membrane Science.1999,155(171-183):
[51]Khayet M. Surface Modification of Polyvinylidene Fluoride Pervaporation Membranes[J]. AIChE Journal.2002,48(12):2833-2843
[52]Wang D, Li K, Teo W K. Preparation and characterization of polyvinylidene fluoride (PVDF) hollow fiber membranes[J]. Journal of Membrane Science.1999,163(2):211-220
[53]Ghosh A K, Jeong B-H, Huang X, et al. Impacts of reaction and curing conditions on polyamide composite reverse osmosis membrane properties[J]. Journal of Membrane Science. 2008,311(1-2):34-45
[54]Chun K Y, Jang S H, Kim H S, et al. Effects of solvent on the pore formation in asymmetric 6FDA-4,40 ODA polyimide membrane:Terms of thermodynamics, precipitation kinetics, and physical factors[J]. Journal of Membrane Science.2000,169:197-214
[55]Tomaszewska M. Preparation and properties of flat-sheet membranes from poly(vinylidene fluoride) for membrane distillation[J]. Desalination.1996,104:1-11
[56]Yeow M L, Liu Y T, Li K. Morphological Study of Poly(vinylidene fluoride) Asymmetric Membranes:Effects of the Solvent, Additive, and Dope Temperature[J]. Journal of Applied Polymer Science.2004,92:1782-1789
[57]Cheng L P. Effect of Temperature on the Formation of Microporous PVDF Membranes by Precipitation from 1-Octanol/DMF/PVDF and Water/DMF/PVDF Systems[J]. Macromolecules.1999,32:6668-6674
[58]Wang X, Zhang L, Sun D, et al. Effect of coagulation bath temperature on formation mechanism of poly(vinylidene fluoride) membrane[J]. Journal of Applied Polymer Science. 2008,110(3):1656-1663
[59]Ying L, Zhai G, Winata A Y, et al. pH effect of coagulation bath on the characteristics of poly(acrylic acid)-grafted and poly(4-vinylpyridine)-grafted poly(vinylidene fluoride) micro filtration membranes[J]. Journal of Colloid and Interface Science.2003,265(2): 396-403
[60]Buonomenna M, Macchi P, Davoli M, et al. Poly(vinylidene fluoride) membranes by phase inversion:the role the casting and coagulation conditions play in their morphology, crystalline structure and properties[J]. European Polymer Journal.2007,43(4):1557-1572
[61]Li Q, Xu Z L, Liu M. Preparation and characterization of PVDF microporous membrane with highly hydrophobic surface[J]. Polymers for Advanced Technologies.2011,22(5): 520-531
[62]J. S T, Roxbury M W. Process for preparing microporous polyvinylidene fluoride membranes[P]. US:4775703 A,1988
[63]Zhang P Y, Wang Y L, Xu Z L, et al. Preparation of poly (vinyl butyral) hollow fiber ultrafiltration membrane via wet-spinning method using PVP as additive[J]. Desalination. 2011,278(1-3):186-193
[64]Yoo S H, Kim J H, Jho J Y, et al. Influence of the addition of PVP on the morphology of asymmetric polyimide phase inversion membranes:effect of PVP molecular weight[J]. Journal of Membrane Science.2004,236(1-2):203-207
[65]Wongchitphimon S, Wang R, Jiraratananon R, et al. Effect of polyethylene glycol (PEG) as an additive on the fabrication of polyvinylidene fluoride-co-hexafluropropylene (PVDF-HFP) asymmetric microporous hollow fiber membranes[J]. Journal of Membrane Science.2011,369(1-2):329-338
[66]Naim R, Ismail A F, Mansourizadeh A. Effect of non-solvent additives on the structure and performance of PVDF hollow fiber membrane contactor for CO2 stripping[J]. Journal of Membrane Science.2012,423-424:503-513
[67]Mansourizadeh A, Ismail A F. Influence of membrane morphology on characteristics of porous hydrophobic PVDF hollow fiber contactors for CO2 stripping from water[J]. Desalination.2012,287:220-227
[68]Liu J, Xu Z, Li X, et al. An improved process to prepare high separation performance PA/PVDF hollow fiber composite nanofiltration membranes[J]. Separation and Purification Technology.2007,58(1):53-60
[69]Rahbari-Sisakht M, Ismail A F, Rana D, et al. Effect of SMM concentration on morphology and performance of surface modified PVDF hollow fiber membrane contactor for CO2 absorption[J]. Separation and Purification Technology.2013,116:67-72
[70]Rahimpour A, Madaeni S, Mansourpanah Y. The effect of anionic, non-ionic and cationic surfactants on morphology and performance of polyethersulfone ultrafiltration membranes for milk concentration[J]. Journal of Membrane Science.2007,296(1-2):110-121
[71]Saedi S, Madaeni S S, Arabi Shamsabadi A, et al. The effect of surfactants on the structure and performance of PES membrane for separation of carbon dioxide from methane[J]. Separation and Purification Technology.2012,99:104-119
[72]Wang D, Li K, Teo W K. Porous PVDF asymmetric hollow fiber membranes prepared with the use of small molecular additives[J]. Journal of Membrane Science.2000,178:13-23
[73]Cui Z, Xu Y, Zhu L, et al. Preparation of PVDF/PEO-PPO-PEO blend microporous membranes for lithium ion batteries via thermally induced phase separation process [J]. Journal of Membrane Science.2008,325(2):957-963
[74]Zhao C, Xu X, Chen J, et al. Effect of graphene oxide concentration on the morphologies and antifouling properties of PVDF ultrafiltration membranes [J]. Journal of Environmental Chemical Engineering.2013,1(3):349-354
[75]Chinnappan A, Kang H C, Kim H. Preparation of PVDF nanofiber composites for hydrogen generation from sodium borohydride[J]. Energy.2011,36(2):755-759
[76]Fontananova E, Jansen J C, Cristiano A, et al. Effect of additives in the casting solution on the formation of PVDF membranes[J]. Desalination.2006,192(1-3):190-197
[77]Kong J F, Li K. Preparation of PVDF Hollow-Fiber Membranes via Immersion Precipitation[J]. Journal of Applied Polymer Science.2001,81:1643-1653
[78]Yeow M L, Liu Y T, Li K. Preparation of porous PVDF hollow fibre membrane via a phase inversion method using lithium perchlorate (LiC104) as an additive[J]. Journal of Membrane Science.2005,258(1-2):16-22
[79]Khayet M, Matsuura T. Preparation and Characterization of Polyvinylidene Fluoride Membranes for Membrane Distillation[J]. Industrial & Engineering Chemistry Research. 2001,40:5710-5718
[80]Uragami T, Naito Y, Sugihara M. Studies on synthesis and permeability of special polymer membranes[J]. Polymer Bulletin.1981,4(10):617-622
[81]Khayet M, Feng C Y, Khulbe K C, et al. Study on the effect of a non-solvent additive on the morphology and performance of ultrafiltration hollow-fiber membranes[J]. Desalination. 2002,148(1-3):321-327
[82]Ahmad A L, Ideris N, Ooi B S, et al. Morphology and polymorph study of a polyvinylidene fluoride (PVDF) membrane for protein binding:Effect of the dissolving temperature[J]. Desalination.2011,278(1-3):318-324
[83]Kuo C Y, Lin H N, Tsai H A, et al. Fabrication of a high hydrophobic PVDF membrane via nonsolvent induced phase separation[J]. Desalination.2008,233(1-3):40-47
[84]Loh C H, Wang R, Shi L, et al. Fabrication of high performance polyethersulfone UF hollow fiber membranes using amphiphilic Pluronic block copolymers as pore-forming additives[J]. Journal of Membrane Science.2011,380(1-2):114-123
[85]Liu F, Hashim N A, Liu Y, et al. Progress in the production and modification of PVDF membranes[J]. Journal of Membrane Science.2011,375(1-2):1-27
[86]Barona G N B, Cha B J, Jung B. Negatively charged poly(vinylidene fluoride) microfiltration membranes by sulfonation[J]. Journal of Membrane Science.2007,290(1-2): 46-54
[87]Du J R, Peldszus S, Huck P M, et al. Modification of poly(vinylidene fluoride) ultrafiltration membranes with poly(vinyl alcohol) for fouling control in drinking water treatment[J]. Water Research.2009,43(18):4559-4568
[88]Xu Z, Li L, Wu F, et al. The application of the modified PVDF ultrafiltration membranes in further purification of Ginkgo biloba extraction[J]. Journal of Membrane Science.2005, 255(1-2):125-131
[89]Boributh S, Chanachai A, Jiraratananon R. Modification of PVDF membrane by chitosan solution for reducing protein fouling[J]. Journal of Membrane Science.2009,342(1-2): 97-104
[90]Kato K, Uchid E, Kang E T, et al. Polymer surface with graft chains[J]. Progress in Polymer Science.2003,28(2):209-259
[91]Hilal N, Kochkodan V, Khatib L A, et al. Surface modified polymeric membranes to reduce (bio)fouling:a microbiological study using E. coli[J]. Desalination.2004, 167(293-300):
[92]Botelho G, Silva M M, Goncalves A M, et al. Performance of electroactive poly(vinylidene fluoride) against UV radiation[J]. Polymer Testing.2008,27(7):818-822
[93]Hilal N, Khatib L A, Zoubi H A, et al. Atomic force microscopy study of membranes modified by surface grafting of cationic polyelectrolyte[J]. Desalination.2005,184(1-3): 45-55
[94]Rahimpour A, Madaeni S S, Zereshki S, et al. Preparation and characterization of modified nano-porous PVDF membrane with high antifouling property using UV photo-grafting[J]. Applied Surface Science.2009,255(16):7455-7461
[95]Zhang M, Nguyen Q T, Ping Z. Hydrophilic modification of poly (vinylidene fluoride) microporous membrane[J]. Journal of Membrane Science.2009,327(1-2):78-86
[96]Kaur S, Ma Z, Gopal R, et al. Plasma-induced immobilization of poly(ethylene glycol) onto poly(vinylidene fluoride) microporous membrane[J]. Langmuir.2007,23(26): 13085-13092
[97]Chan C M, Ko T M. Polymer surface modification by plasmas and photons[J]. Surface Science Reports.1996,24:1-54
[98]Wang P, Tan K L, Kang E T, et al. Plasma-induced immobilization of poly(ethylene glycol) onto poly(vinylidene fluoride) microporous membrane[J]. Journal of Membrane Science.2002,195:103-114
[99]Buonomenna M G, Lopez L C, Favia P, et al. New PVDF membranes:The effect of plasma surface modification on retention in nanofiltration of aqueous solution containing organic compounds[J]. Water Research.2007,41(19):4309-4316
[100]Chen Y, Ying L, Yu W, et al. Poly(vinylidene fluoride) with Grafted Poly(ethylene glycol) Side Chains Poly(ethylene glycol) Side Chains via the RAFT-Mediated Process and Pore Size Control of the Copolymer Membranes[J]. Macromolecules.2003,36:9451-9457
[101]Wang P, Tan K L, Kang E T, et al. Synthesis, characterization and anti-fouling properties of poly(ethylene glycol) grafted poly(vinylidene fluoride) copolymer membranes[J]. Journal of Materials Chemistry.2001,11(3):783-789
[102]Liu F, Du C H, Zhu B K, et al. Surface immobilization of polymer brushes onto porous poly(vinylidene fluoride) membrane by electron beam to improve the hydrophilicity and fouling resistance[J]. Polymer.2007,48(10):2910-2918
[103]Moad G, Rizzardo E, Thang S H. Radical addition-fragmentation chemistry in polymer synthesis[J]. Polymer.2008,49(5):1079-1131
[104]Chiefari J, Chong Y K, Ercole F, et al. Living free-radical polymerization by reversible addition-fragmentation chain transfer:the RAFT process[J]. Macromolecules.1998, 31(16):5559-5562
[105]Hester J F, Mayes A M. Design and performance of foul-resistant poly(vinylidene fluoride) membranes prepared in a single-step by surface segregation[J]. Journal of Membrane Science.2002,202:119-135
[106]Akthakul A, Salinaro R F, Mayes A M. Antifouling Polymer Membranes with Subnanometer Size Selectivity [J]. Macromolecules.2004,37:7663-7668
[107]Matyjaszewski K, Xia J. Atom transfer radical polymerization[J]. Chemical Reviews. 2001,101(9):2921-2990
[108]Cunningham M F. Controlled/living radical polymerization in aqueous dispersed systems[J]. Progress in Polymer Science.2008,33(4):365-398
[109]Singh N, Husson S M, Zdyrko B, et al. Surface modification of microporous PVDF membranes by ATRP[J]. Journal of Membrane Science.2005,262(1-2):81-90
[110]Liu D, Chen Y, Zhang N, et al. Controlled grafting of polymer brushes on poly(vinylidene fluoride) films by surface-initiated atom transfer radical polymerization[J]. Journal of Applied Polymer Science.2006,101(6):3704-3712
[111]Zhao Y H, Qian Y L, Pang D X, et al. Porous membranes modified by hyperbranched polymers Ⅱ. Effect of the arm length of amphiphilic hyperbranched-star polymers on the hydrophilicity and protein resistance of poly(vinylidene fluoride) membranes[J]. Journal of Membrane Science.2007,304(1-2):138-147
[112]Wei Y, Chu H Q, Dong B Z, et al. Effect of TiO2 nanowire addition on PVDF ultrafiltration membrane performance[J]. Desalination.2011,272(1-3):90-97
[113]Li J H, Li M Z, Miao J, et al. Improved surface property of PVDF membrane with amphiphilic zwitterionic copolymer as membrane additive[J]. Applied Surface Science.2012, 258(17):6398-6405
[114]Chang Y, Ko C Y, Shih Y J, et al. Surface grafting control of PEGylated poly(vinylidene fluoride) antifouling membrane via surface-initiated radical graft copolymerization[J]. J. Membr. Sci.2009,345(1-2):160-169
[115]Hester J F, Banerjee P, Won Y Y, et al. ATRP of Amphiphilic Graft Copolymers Based on PVDF and Their Use as Membrane Additives[J]. Macromolecules.2002,35(20): 7652-7661
[116]Ying L, Kang E T, Neoh K G. Covalent immobilization of glucose oxidase on microporous membranes prepared from poly(vinylidene fluoride) with grafted poly(acrylic acid) side chains[J]. Journal of Membrane Science.2002,208:361-374
[117]Ying L, Kang E T, Neoh K G, et al. Drug permeation through temperature-sensitive membranes prepared from poly(vinylidene fluoride) with grafted poly(N-isopropylacrylamide) chains[J]. Journal of Membrane Science.2004,243:253-262
[118]Sui Y, Gao X, Wang Z, et al. Antifouling and antibacterial improvement of surface-functionalized poly(vinylidene fluoride) membrane prepared via dihydroxyphenylalanine-initiated atom transfer radical graft polymerizations [J]. Journal of Membrane Science.2012,394-395:107-119
[119]Chen Y, Liu D, Deng Q, et al. Atom transfer radical polymerization directly from poly(vinylidene fluoride):Surface and antifouling properties[J]. Journal of Polymer Science Part A:Polymer Chemistry.2006,44(11):3434-3443
[120]Li M Z, Li J H, Shao X S, et al. Grafting zwitterionic brush on the surface of PVDF membrane using physisorbed free radical grafting technique[J]. Journal of Membrane Science. 2012,405-406:141-148
[121]Chen Y, Deng Q, Xiao J, et al. Controlled grafting from poly(vinylidene fluoride) microfiltration membranes via reverse atom transfer radical polymerization and antifouling properties[J]. Polymer.2007,48(26):7604-7613
[122]Chen Y, Sun W, Deng Q, et al. Controlled grafting from poly(vinylidene fluoride) films by surface-initiated reversible addition-fragmentation chain transfer polymerization[J]. Journal of polymer science. Part A, Polymer Chemistry.2006,44(9):3071-3082
[123]Kim J H, Min B R, Won J, et al. Phase behavior and mechanism of membrane formation for polyimide/DMSO/water system[J]. Joural of Membrane Science 2001,187: 47-55
[124]Ochoa N. Effect of hydrophilicity on fouling of an emulsified oil wastewater with PVDF/PMMA membranes[J]. Journal of Membrane Science.2003,226(1-2):203-211
[125]Nunes S P, Peinemann K V. Ultrafiltration membranes from PVDF/PMMA blends[J]. Journal of Membrane Science.1992,73(1):25-35
[126]Masuelli M, Marchese J, Ochoa N A. SPC/PVDF membranes for emulsified oily wastewater treatment[J]. Journal of Membrane Science.2009,326(2):688-693
[127]Li N, Xiao C, An S, et al. Preparation and properties of PVDF/PVA hollow fiber membranes[J]. Desalination.2010,250(2):530-537
[128]Basilio N, Garcia-Rio L, Martin-Pastor M. Calixarene-Based Surfactants:Evidence of Structural Reorganization upon Micellization[J]. Langmuir.2012,28(5):2404-2414
[129]Uragami T, Fujimoto M, Sugihara M. Studies on synthesis and permeabilities of special polymer membranes.28. Permeation characteristics and structure of interpolymer membranes from poly(vinylidene fluoride) and poly (styrene sulfonic acid)[J]. Desalination. 1980,34(3):311-323
[130]Hester J F, Banerjee P, Mayes A M. Preparation of Protein-Resistant Surfaces on Poly(vinylidene fluoride) Membranes via Surface Segregation[J]. Macromolecules.1999,32: 1643-1650
[131]Liu F, Xu Y Y, Zhu B K, et al. Preparation of hydrophilic and fouling resistant poly(vinylidene fluoride) hollow fiber membranes[J]. Journal of Membrane Science.2009, 345(1-2):331-339
[132]Hester J F, Olugebefola S C, Mayes A M. Preparation of pH-responsive polymer membranes by self-organization[J]. Journal of Membrane Science.2002,208:375-388
[133]Yuliwati E, Ismail A F. Effect of additives concentration on the surface properties and performance of PVDF ultrafiltration membranes for refinery produced wastewater treatment[J]. Desalination.2011,273(1):226-234
[134]Zhai G, Ying L, Kang E T, et al. Synthesis and characterization of poly(vinylidene fluoride) with grafted acid/base polymer side chains[J]. Macromolecules.2002,35(26): 9653-9656
[135]Ying L, Wang P, Kang E T, et al. Synthesis and characterization of poly(acrylic acid)-graft-poly(vinylidene fluoride) copolymers and pH sensitive membranes[J]. Macromolecules.2001,35(3):673-679
[136]Liu X, Neoh K G, Kang E T. Redox-sensitive microporous membranes prepared from poly(vinylidene fluoride) grafted with viologen-containing polymer side chains[J]. Macromolecules.2003,36(22):8361-8367
[137]Sui Y, Wang Z, Gao X, et al. Antifouling PVDF ultrafiltration membranes incorporating PVDF-g-PHEMA additive via atom transfer radical graft polymerizations[J]. Journal of Membrane Science.2012,413-414:38-47
[138]Zhao Y H, Zhu B K, Kong L, et al. Improving Hydrophilicity and Protein Resistance of Poly(vinylidene fluoride) Membranes by Blending with Amphiphilic Hyperbranched-Star Polymer[J]. Langmuir.2007,23:5779-5786
[139]Tahiri Alaoui O, Nguyen Q T, Mbareck C, et al. Elaboration and study of poly(vinylidene fluoride)-anatase TiO2 composite membranes in photocatalytic degradation of dyes[J]. Applied Catalysis A:General.2009,358(1):13-20
[140]Yu L Y, Xu Z L, Shen H M, et al. Preparation and characterization of PVDF SiO2 composite hollow fiber UF membrane by sol-gel method[J]. Journal of Membrane Science. 2009,337(1-2):257-265
[141]Bottino A, Capannelli G, Comite A. Preparation and characterization of novel porous PVDF-ZrO2 composite membranes[J]. Desalination.2002,146(1-3):35-40
[142]Ma J, Wang Z, Pan M, et al. A study on the multifunction of ferrous chloride in the formation of poly(vinylidene fluoride) ultrafiltration membranes[J]. Journal of Membrane Science.2009,341(1-2):214-224
[143]Dong C, He G, Li H, et al. Antifouling enhancement of poly(vinylidene fluoride) microfiltration membrane by adding Mg(OH)2 nanoparticles[J]. Journal of Membrane Science. 2012,387-388:40-47
[144]Manful J T, Grimm C C, Gayin J, et al. Effect of Variable Parboiling on Crystallinity of Rice Samples[J]. Cereal Chemistry.2008,85(1):92-95
[145]Yang Y, Yang D, Zhang S, et al. Preparation and characterization of poly(phthalazinone ether sulfone ketone) hollow fiber ultrafiltration membranes with excellent thermal stability [J]. Journal of Membrane Science.2006,280(1-2):957-968
[146]Lin D J, Beltsios K, Chang C L, et al. Fine Structure and Formation Mechanism of Particulate Phase-Inversion Poly(vinylidene fluoride) Membranes[J]. Jouranl of Polymer Science, Part B:Polymer Physics.2003:1578-1588
[147]Teshima K, Sugimura H, Inoue Y, et al. Ultra-Water-Repellent Poly(ethylene terephthalate) Substrates[J]. Langmuir.2003,19:10624-10627
[148]Allegrezza A E, Bellantoni E C. Porous membrane formed from interpenetrating polymer network having hydrophilic surface[P]. EP:0430082 B1,1996
[149]Koguma I, Nagoya F. Microporous hydrophilic membrane[P]. EP:1099468 A3,2002
[150]Mullette D, Muller J, Patel N. Membrane post treatment[P]. US:8262778 B2,2012
[151]Xu Y Y, Xu Z K. Polymer Membrane Material[M]. Chemical Industry Press:Beijing, 2005
[152]Wang S M, Wang Z, Zhang Y, et al. Experimental study of the control of pore sizes of porous membranes applying chemicals methods[J]. Desalination.2005,177(1-3):7-13
[153]Yoo S H, Kim J H, Jho J Y, et al. Influence of the addition of PVP on the morphology of asymmetric polyimide phase inversion membranes:effect of PVP molecular weight[J]. Journal of Membrane Science.2004,236(1-2):203-207
[154]Hou D, Wang J, Qu D, et al. Fabrication and characterization of hydrophobic PVDF hollow fiber membranes for desalination through direct contact membrane distillation[J]. Separation and Purification Technology.2009,69(1):78-86
[155]Mansourizadeh A, Ismail A F. Preparation and characterization of porous PVDF hollow fiber membranes for CO2 absorption:Effect of different non-solvent additives in the polymer dope[J]. International Journal of Greenhouse Gas Control.2011,5(4):640-648
[156]Yan L, Li Y S, Xiang C B. Preparation of poly(vinylidene fluoride)(pvdf) ultrafiltration membrane modified by nano-sized alumina (Al2O3) and its antifouling research[J]. Polymer.2005,46(18):7701-7706
[157]Elashmawi I S. Effect of LiCl filler on the structure and morphology of PVDF films[J]. Materials Chemistry and Physics.2008,107(1):96-100
[158]Mansourizadeh A, Ismail A F. Effect of LiCl concentration in the polymer dope on the structure and performance of hydrophobic PVDF hollow fiber membranes for CO2 absorption[J]. Chemical Engineering Journal.2010,165(3):980-988
[159]Amirilargani M, Saljoughi E, Mohammadi T. Effects of Tween 80 concentration as a surfactant additive on morphology and permeability of flat sheet polyethersulfone (PES) membranes[J]. Desalination.2009,249(2):837-842
[160]Amirilargani M, Saljoughi E, Mohammadi T. Improvement of permeation performance of polyethersulfone (PES) ultrafiltration membranes via addition of Tween-20[J]. Journal of Applied Polymer Science.2010,115(1):504-513
[161]Ghosh S. Comparative studies on brij reverse micelles prepared in benzene/surfactant/ethylammonium nitrate systems:Effect of head group size and polarity of the hydrocarbon chain[J]. Journal of Colloid and Interface Science.2011,360(2):672-680
[162]Sukitpaneenit P, Chung T S. Molecular elucidation of morphology and mechanical properties of PVDF hollow fiber membranes from aspects of phase inversion, crystallization and rheology[J]. Journal of Membrane Science.2009,340(1-2):192-205
[163]Tran Le T, Saveyn P, Hoa H D, et al. Determination of heat-induced effects on the particle size distribution of casein micelles by dynamic light scattering and nanoparticle tracking analysis[J]. International Dairy Journal.2008,18(12):1090-1096
[164]Santiago P S, Moura F, Moreira L M, et al. Dynamic Light Scattering and Optical Absorption Spectroscopy Study of pH and Temperature Stabilities of the Extracellular Hemoglobin of Glossoscolex paulistus[J]. Biophysical Journal.2008,94(6):2228-2240
[165]Falcone R D, Correa N M, Silber J J. On the Formation of New Reverse Micelles:A Comparative Study of Benzene/Surfactants/Ionic Liquids Systems Using UV-Visible Absorption Spectroscopy and Dynamic Light Scattering[J]. Langmuir.2009,25(18): 10426-10429
[166]Panu S, Chung T S. Molecular elucidation ofmorphology and mechanical properties of PVDF hollowfibermembranes fromaspects of phase inversion[J]. Journal of Membrane Science.2009,340:192-205
[167]Loos K, Bolker A, Zettl H, et al. Micellar Aggregates of Amylose-block-polystyrene Rod-Coil Block Copolymers in Water and THF[J]. Macromolecules.2005,38:873-879
[168]Lund A, Gustafsson C, Bertilsson H, et al. Enhancement of β phase crystals formation with the use of nanofillers in PVDF films and fibres[J]. Combustion Science and Technology.2011,71(2):222-229
[169]Sukitpaneenit P, Chung T S. Molecular elucidation of morphology and mechanical properties of PVDF hollow fiber membranes from aspects of phase inversion, crystallization and rheology[J]. Journal of Membrane Science.2009,340(1-2):192-205
[170]Strathmann H. Membrane Separation Processes:Current Relevance and Future Opportunities[J]. AIChE Journal.2001,47(5):1077-1087
[171]Awanis Hashim N, Liu F, Moghareh Abed M R, et al. Chemistry in spinning solutions:Surface modification of PVDF membranes during phase inversion[J]. Journal of Membrane Science.2012,415-416:399-411
[172]Field R, Hang S, Arnot T. The influence of surfactant on water flux through microfiltration membranes[J]. Journal of Membrane Science.1994,86(3):291-304
[173]Curcio E, Fontananova E, Profio G D, et al. Influence of the Structural Properties of Poly(vinylidene fluoride) Membranes on the Heterogeneous Nucleation Rate of Protein Crystals[J]. Journal of Physical Chemistry B.2006,110(25):12438-12445
[174]Yang Q, Kang X Z, Wei D Z, et al. Surface Modification of Polypropylene Microporous Membranes with a Novel Glycopolymer[J]. Chemistry of Materials.2005,17: 3050-3058
[175]Widanapathirana L, Zhao Y. Effects of Amphiphile Topology on the Aggregation of Oligocholates in Lipid Membranes:Macrocyclic versus Linear Amphiphiles[J]. Langmuir. 2012,28(21):8165-8173
[176]Fan X, Huang B, Wang G, et al. Synthesis of Amphiphilic Heteroeight-Shaped PolymerCyclic-[Poly(ethylene oxide)-b-polystyrene]2 via "Click" Chemistry [J]. Macromolecules.2012,45(9):3779-3786
[177]Yeow M L, Liu Y T, Li K. Isothermal Phase Diagrams and Phase-Inversion Behavior of Poly(vinylidene fluoride)/Solvents/Additives/Water Systems[J]. Journal of Applied Polymer Science.2003,90:2150-2155
[178]Hashim N A, Liu F, Li K. A simplified method for preparation of hydrophilic PVDF membranes from an amphiphilic graft copolymer[J]. Journal of Membrane Science.2009, 345(1-2):134-141
[179]Neugebauer D. Graft copolymers with poly(ethylene oxide) segments[J]. Polymer International.2007,56(12):1469-1498
[180]Zhou S, Sakamoto T, Wang J, et al. One-Dimensional Assembly of Silica Nanospheres:Effects of Nonionic Block Copolymers[J]. Langmuir.2012,28(37): 13181-13188
[181]Law S J, Britton M M. Sizing of Reverse Micelles in Microemulsions using NMR Measurements of Diffusion[J]. Langmuir.2012,28(32):11699-11706
[182]Letchford K, Burt H. A review of the formation and classification of amphiphilic block copolymer nanoparticulate structures:micelles, nanospheres, nanocapsules and polymersomes[J]. European Journal of Pharmaceutics and Biopharmaceutics.2007,65(3): 259-269
[183]Lu X, Gong S, Meng L, et al. Novel fluorescent amphiphilic block copolymers: Controllable morphologies and size by self-assembly [J]. European Polymer Journal.2007, 43(7):2891-2900
[184]Petkova R, Tcholakova S, Denkov N D. Foaming and Foam Stability for Mixed Polymer-Surfactant Solutions:Effects of Surfactant Type and Polymer Charge[J]. Langmuir. 2012,28(11):4996-5009
[185]Zhang P Y, Yang H, Xu Z L, et al. Characterization and preparation of poly(vinylidene fluoride) (PVDF) microporous membranes with interconnected bicontinuous structures via non-solvent induced phase separation (NIPS)[J]. Journal of Polymer Research. 2013,20(66-78):
[186]Shi F, Ma Y, Ma J, et al. Preparation and characterization of PVDF/TiO2 hybrid membranes with ionic liquid modified nano-TiO2 particles[J]. Journal of Membrane Science. 2013,427:259-269
[187]Ma H, Burger C, Hsiao B S, et al. Highly Permeable Polymer Membranes Containing Directed Channels for Water Purification[J]. ACS Macro Letters.2012,1(6):723-726
[188]Hussain H, Tan B H, Gudipati C S, et al. Micelle Formation of Amphiphilic Polystyrene-b-poly(N-vinylpyrrolidone) Diblock Copolymer in Methanol and Water-Methanol Binary Mixtures[J]. Langmuir.2009,25(10):5557-5564
[189]Zhang W, Shi L, An Y, et al. A Convenient Method of Tuning Amphiphilic Block Copolymer Micellar Morphology [J]. Macromolecules.2004,37:2551-2555
[190]Low YKA, Tan L Y, Tan L P, et al. Increasing Solvent Polarity and Addition of Salts Promote b-Phase Poly(vinylidene fluoride) Formation[J]. Journal of Applied Polymer Science. 2013,128(5):2902-2910
[191]Stropnik C, Kaiser V. Polymeric membranes preparation by wet phase separation: mechanisms and elementary processes[J]. Desalination.2002,145(1-2):1-10
[192]He X, Chen C, Jiang Z, et al. Computer simulation of formation of polymeric ultrafiltration membrane via immersion precipitation[J]. Journal of Membrane Science.2011, 371(1-2):108-116
[193]Zhou B, Powell A C. Phase field simulations of early stage structure formation during immersion precipitation of polymeric membranes in 2D and 3D[J]. Journal of Membrane Science.2006,268(2):150-164
[194]Lin D J, Chang C L, Huang F M, et al. Effect of salt additive on the formation of microporous polyvinylidene difluoride) membranes by phase inversion from LiClO4/Water/DMF/PVDF system[J]. Polymer.2003,44(2):413-422
[195]Elashmawi I S. Effect of LiCl filler on the structure and morphology of PVDF films[J]. Materials Chemistry and Physics 2008,107(1):96-100
[196]Zhang P Y, Xu Z L, Yang H, et al. Fabrication and characterization of PVDF membranes via an in situ free radical polymerization method[J]. Chemical Engineering Science.2013,97:296-308