烯丙基葡糖修饰聚合物分离膜的研究
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摘要
本论文的主要研究内容为对聚丙烯腈微孔膜的共聚改性以及对聚丙烯微孔膜的表面改性。通过共聚方法将亲水性烯丙基葡糖接枝到聚丙烯腈分子链上，再用浸入沉淀相转化法制备其共聚物微孔膜，得到具有较好的亲水性、高抗污染性、以及具有适宜生物相容性的聚丙烯腈共聚物(PANCAG)分离膜材料。通过表面改性的方法将烯丙基葡糖接枝到聚丙烯微孔膜的表面，极大改善了聚丙烯微孔膜的亲水性和生物相容性。
以干燥的HCl气体为催化剂，通过丙烯醇与无水葡萄糖合成了用于改性的烯丙基葡糖单体。通过红外、核磁等分析对糖的结构进行了表征。
以AIBN为引发剂，烯丙基葡糖与丙烯腈进行溶液聚合。考察了反应时间、引发剂浓度、原料配比、以及溶剂等因素对聚合反应的影响。对合成的聚合物进行了红外、核磁、元素分析和分子量的表征。研究发现最佳聚合条件为：催化剂与单体的配比为1:500(摩尔比)，反应时间为6小时，在此条件下最高粘均分子量为7.21万，最高产率为76％，共聚物最高含糖量为23.36wt.％。
通过烯丙基葡糖与丙烯腈的水相沉淀聚合以提高共聚物的分子量、产率以及糖含量。研究了单体配比、引发剂浓度、反应温度、搅拌以及pH值等条件对聚合反应的影响。研究发现，最佳的聚合条件为：反应温度70℃，pH值2.0—3.5，引发剂与单体配比为1:500。将得到的聚合物进行了红外光谱、核磁共振、元素分析以及分子量的测定。通过对比溶液聚合和水相沉淀聚合的结果，发现在相同的单体配比时水相沉淀聚合的产率和聚合物中糖的含量都较高(产率可达89％，含糖量可达42.24wt.％)，并且水相沉淀聚合的分子量比溶液聚合的分子量大(粘均分子量最高可为36.32万)。
对上述共聚物／溶剂(DMSO)／非溶剂(水)三元体系进行了相分离行为的研究，为选取合适的制膜液提供理论依据。测定了不同聚合物在不同的温度下的浊点，结果表明此三元体系符合LCP方程。结合浊点测定及浊点线性方程(LCP)，得到了共聚物／DMSO／H_2O三元体系在不同温度、不同共聚物组成时的相图，发现随着聚合物中糖含量的增加，双节线向聚合物／非溶剂轴靠近。
浙江大学博士论文
根据得到的相图，以浸没沉淀相转化法制备了丙烯睛/烯丙基葡糖共聚物分
离膜材料，测定了其水通量、BSA吸附性质，并通过扫描电镜观察其微结构。发
现聚合物中糖含量增加，膜叭水通量增加;凝固液温度升高，膜的水通量增加;
含糖量高的聚合物膜的BSA吸附值低，其抗污染能力增强。由扫描电镜分析发现，
所制得的共聚物膜具有非对称结构:为致密的皮层和较疏松的大孔支撑层。
发明了一种简单的等离子体改性工艺:首先把接枝单体涂敷在聚丙烯微孔膜
的表面，蒸发溶剂;然后用等离子体辐射接枝，以便通过化学键把接枝单体固定
在聚丙烯微孔膜的表面。并用扫描电镜对改性后膜表面结构的变化进行观察，用
XPS对改性后膜表面化学基团的变化进行表征。研究了接枝条件对接枝率的影
响，发现接枝率随单体浓度以及等离子体处理时间的增加而上升，但当单体浓度
或等离子体处理时间增加到一定值后，接枝率反而有所下降。因此得出该实验最
佳接枝条件为:接枝单体最佳浓度为0.39/ml，等离子体最佳处理时间为10分钟。
盏
通过测定改性后接触角的变化对亲水性改性的效果进行表征，发现接触角随烯丙
基葡糖接枝率的增加而大大下降，未改性聚丙烯微孔膜接触角为1 180，改性后可
下降到340，说明接枝后膜的亲水性有了极大的改善，并且亲水性可长久保持。
对改性后膜的抗污染性能作了研究，发现改性膜对蛋白质吸附的量要大大少于未
改性膜;当对蛋白质溶液进行过滤时，未改性膜最大通量损失可达80%，改性膜
只下降40%左右，并且改性膜比未改性膜更容易清洗，说明通过接枝烯丙基葡糖
对膜的抗污染性能有了较大的改善。
To change the surface property from hydrophobic to hydrophilic efficiently and to improve the anti-fouling property, the modification of polyacrylontrile (PAN) and polypropylene (PP) membrane materials by using a-allyl glucoside (AG) as functional agent was introduced in this paper. For the modification of PAN, AG was incorporated into PAN by water-phase precipitation copolymerization and the obtained copolymer (PANCAG) was fabricated into membrane by immerse precipitation phase inversion method. For the modification of PP microporous membrane, AG was grafted onto the surface of PP membrane by Na-plasma induced graft polymerization method. The results demonstrated that the modified membranes combined the properties of high hydrophilicity, anti-fouling, and excellent biocompatibility.
First, the copolymer was synthesized in dimethylsul- phoxide (DMSO) by the radical copolymerization of AG with AN using 2,2'-azobisisobutyronitrile(AIBN) as initiator. The copolymers were characterized by FT-IR and H'-NMR spectroscopy. It was found that the copolymer yields increased with increasing the initiator concentration as well as reaction time, and decreased with increasing the monomer ratio of AG/AN. Raising the proportion of AG in the monomer mixture principally increased the AG content in the copolymers. The Mv of the obtained copolymers decreased with increasing the AG monomer content and initiator concentration.
In order to improve the Mv and AG content in the copolymer, AG was then incorporated into polyacrylonitrile by water-phase precipitation copolymerization with KiSiOg-NaiSOs as initiator system. The effects of initiator concentration, reaction time and temperature, and total monomer concentration on the copolymerization were studied and some results were compared with those of solution copolymerization using AIBN as initiator. FT-IR, 1H- and 13C- NMR spectroscopes, element analysis and DSC measurement were used to characterize the copolymers. It was found that both the yield and molecular weight for the WPPCP were higher than those for solution polymerization. The AG content in the resulted copolymers
and the AG conversion for WPPCP were also higher than those of solution polymerization. The surface properties of the carbohydrate-containing copolymers were studied by pure water contact angle, protein adsorption and cell adhesion measurements. It was found that the contact angle of the copolymer films decreased from 68?to 30?with the increase of AG content in the copolymer. The adsorption amount of bovine serum albumin (BSA) and the adhesive number of macrophage on the film surface also decreased significantly with increasing the oc-allyl glucoside content from 0 to 42wt.% in the copolymer. These results revealed that both the hydrophilicity and biocompatibility of polyacrylonitrile-based membranes could be improved by copolymerization acrylonitrile with vinyl carbohydrates.
The phase separation behavior of the copolymer dope was studied according to the linerized cloud point (LCP) correlation. It was found that the phase separation behavior of the systems, copolymer-solvent (DMSO)-nonsolvent (HaQ), agreed with the LCP correction. The binodal of the systems calculated according to the LCP correlation was shifted away the copolymer/DMSO axis with the increasing of the AG content in copolymer. The membranes prepared by immerse precipitation phase inversion method was characterized by water flux, BSA absorption, and SEM. The water flux increased with the increasing of AG content in copolymer, while the amount of BSA absorbed decreased with the increasing of AG content in copolymer which indicated that the modified membranes had high hydrophilicity and good biocompatibility.
Finally, AG was grafted onto the surface of PP membrane by Na-plasma induced graft polymerization method. The chemical and morphological changes of the membrane surface of the grafted membranes were confirmed by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), pure
以干燥的HCl气体为催化剂，通过丙烯醇与无水葡萄糖合成了用于改性的烯丙基葡糖单体。通过红外、核磁等分析对糖的结构进行了表征。
以AIBN为引发剂，烯丙基葡糖与丙烯腈进行溶液聚合。考察了反应时间、引发剂浓度、原料配比、以及溶剂等因素对聚合反应的影响。对合成的聚合物进行了红外、核磁、元素分析和分子量的表征。研究发现最佳聚合条件为：催化剂与单体的配比为1:500(摩尔比)，反应时间为6小时，在此条件下最高粘均分子量为7.21万，最高产率为76％，共聚物最高含糖量为23.36wt.％。
通过烯丙基葡糖与丙烯腈的水相沉淀聚合以提高共聚物的分子量、产率以及糖含量。研究了单体配比、引发剂浓度、反应温度、搅拌以及pH值等条件对聚合反应的影响。研究发现，最佳的聚合条件为：反应温度70℃，pH值2.0—3.5，引发剂与单体配比为1:500。将得到的聚合物进行了红外光谱、核磁共振、元素分析以及分子量的测定。通过对比溶液聚合和水相沉淀聚合的结果，发现在相同的单体配比时水相沉淀聚合的产率和聚合物中糖的含量都较高(产率可达89％，含糖量可达42.24wt.％)，并且水相沉淀聚合的分子量比溶液聚合的分子量大(粘均分子量最高可为36.32万)。
对上述共聚物／溶剂(DMSO)／非溶剂(水)三元体系进行了相分离行为的研究，为选取合适的制膜液提供理论依据。测定了不同聚合物在不同的温度下的浊点，结果表明此三元体系符合LCP方程。结合浊点测定及浊点线性方程(LCP)，得到了共聚物／DMSO／H_2O三元体系在不同温度、不同共聚物组成时的相图，发现随着聚合物中糖含量的增加，双节线向聚合物／非溶剂轴靠近。
浙江大学博士论文
根据得到的相图，以浸没沉淀相转化法制备了丙烯睛/烯丙基葡糖共聚物分
离膜材料，测定了其水通量、BSA吸附性质，并通过扫描电镜观察其微结构。发
现聚合物中糖含量增加，膜叭水通量增加;凝固液温度升高，膜的水通量增加;
含糖量高的聚合物膜的BSA吸附值低，其抗污染能力增强。由扫描电镜分析发现，
所制得的共聚物膜具有非对称结构:为致密的皮层和较疏松的大孔支撑层。
发明了一种简单的等离子体改性工艺:首先把接枝单体涂敷在聚丙烯微孔膜
的表面，蒸发溶剂;然后用等离子体辐射接枝，以便通过化学键把接枝单体固定
在聚丙烯微孔膜的表面。并用扫描电镜对改性后膜表面结构的变化进行观察，用
XPS对改性后膜表面化学基团的变化进行表征。研究了接枝条件对接枝率的影
响，发现接枝率随单体浓度以及等离子体处理时间的增加而上升，但当单体浓度
或等离子体处理时间增加到一定值后，接枝率反而有所下降。因此得出该实验最
佳接枝条件为:接枝单体最佳浓度为0.39/ml，等离子体最佳处理时间为10分钟。
盏
通过测定改性后接触角的变化对亲水性改性的效果进行表征，发现接触角随烯丙
基葡糖接枝率的增加而大大下降，未改性聚丙烯微孔膜接触角为1 180，改性后可
下降到340，说明接枝后膜的亲水性有了极大的改善，并且亲水性可长久保持。
对改性后膜的抗污染性能作了研究，发现改性膜对蛋白质吸附的量要大大少于未
改性膜;当对蛋白质溶液进行过滤时，未改性膜最大通量损失可达80%，改性膜
只下降40%左右，并且改性膜比未改性膜更容易清洗，说明通过接枝烯丙基葡糖
对膜的抗污染性能有了较大的改善。
To change the surface property from hydrophobic to hydrophilic efficiently and to improve the anti-fouling property, the modification of polyacrylontrile (PAN) and polypropylene (PP) membrane materials by using a-allyl glucoside (AG) as functional agent was introduced in this paper. For the modification of PAN, AG was incorporated into PAN by water-phase precipitation copolymerization and the obtained copolymer (PANCAG) was fabricated into membrane by immerse precipitation phase inversion method. For the modification of PP microporous membrane, AG was grafted onto the surface of PP membrane by Na-plasma induced graft polymerization method. The results demonstrated that the modified membranes combined the properties of high hydrophilicity, anti-fouling, and excellent biocompatibility.
First, the copolymer was synthesized in dimethylsul- phoxide (DMSO) by the radical copolymerization of AG with AN using 2,2'-azobisisobutyronitrile(AIBN) as initiator. The copolymers were characterized by FT-IR and H'-NMR spectroscopy. It was found that the copolymer yields increased with increasing the initiator concentration as well as reaction time, and decreased with increasing the monomer ratio of AG/AN. Raising the proportion of AG in the monomer mixture principally increased the AG content in the copolymers. The Mv of the obtained copolymers decreased with increasing the AG monomer content and initiator concentration.
In order to improve the Mv and AG content in the copolymer, AG was then incorporated into polyacrylonitrile by water-phase precipitation copolymerization with KiSiOg-NaiSOs as initiator system. The effects of initiator concentration, reaction time and temperature, and total monomer concentration on the copolymerization were studied and some results were compared with those of solution copolymerization using AIBN as initiator. FT-IR, 1H- and 13C- NMR spectroscopes, element analysis and DSC measurement were used to characterize the copolymers. It was found that both the yield and molecular weight for the WPPCP were higher than those for solution polymerization. The AG content in the resulted copolymers
and the AG conversion for WPPCP were also higher than those of solution polymerization. The surface properties of the carbohydrate-containing copolymers were studied by pure water contact angle, protein adsorption and cell adhesion measurements. It was found that the contact angle of the copolymer films decreased from 68?to 30?with the increase of AG content in the copolymer. The adsorption amount of bovine serum albumin (BSA) and the adhesive number of macrophage on the film surface also decreased significantly with increasing the oc-allyl glucoside content from 0 to 42wt.% in the copolymer. These results revealed that both the hydrophilicity and biocompatibility of polyacrylonitrile-based membranes could be improved by copolymerization acrylonitrile with vinyl carbohydrates.
The phase separation behavior of the copolymer dope was studied according to the linerized cloud point (LCP) correlation. It was found that the phase separation behavior of the systems, copolymer-solvent (DMSO)-nonsolvent (HaQ), agreed with the LCP correction. The binodal of the systems calculated according to the LCP correlation was shifted away the copolymer/DMSO axis with the increasing of the AG content in copolymer. The membranes prepared by immerse precipitation phase inversion method was characterized by water flux, BSA absorption, and SEM. The water flux increased with the increasing of AG content in copolymer, while the amount of BSA absorbed decreased with the increasing of AG content in copolymer which indicated that the modified membranes had high hydrophilicity and good biocompatibility.
Finally, AG was grafted onto the surface of PP membrane by Na-plasma induced graft polymerization method. The chemical and morphological changes of the membrane surface of the grafted membranes were confirmed by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), pure
引文
1. H.K. Lonsdale, Growth of membrane technology; J. Membrane Sci., 10, 81(1982).
2. E.A. Mason; From pig bladders and cracked jars to polysulfones: an historical perspective on membrane transport; J. Membrane Sci., 60, 125(1991).
3．M．Mulder著，李琳译，膜技术基本原理，2nd，清华大学出版社，1999
4. Pellegrino J., Separation and Purification Methods, 29 (1), 91 (2000).
5. M.H. Mulder; Basic principles of membrane technology; Kluwer, Dordrecht, 1991.
6．王学松编著，膜分离技术及其应用，科学出版社，北京，1994。
7. Strathmann H., Synthetic Membranes and Their Preparation, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp1.
8．时钧，袁权，高从阶编，膜技术手册，化学工业出版社，北京，2001。
9．王乐夫，《膜工艺》，化学工业出版社，1998，pp15。
10. Porter M.C, Microfiltration, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp.61.
11. Schnbein C., British Patent 11,402 (1846).
12. Sudak R.G, Reverse Osmosis, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp260.
13. Kesting R.E., Synthetic Polymeric Membranes: A Structure Perspective, 2nd Ed., Wiley-Interscience, New York, 1985, pp134.
14．陈观文，膜科学与技术，19(6)，52(1999)．
2. E.A. Mason; From pig bladders and cracked jars to polysulfones: an historical perspective on membrane transport; J. Membrane Sci., 60, 125(1991).
3．M．Mulder著，李琳译，膜技术基本原理，2nd，清华大学出版社，1999
4. Pellegrino J., Separation and Purification Methods, 29 (1), 91 (2000).
5. M.H. Mulder; Basic principles of membrane technology; Kluwer, Dordrecht, 1991.
6．王学松编著，膜分离技术及其应用，科学出版社，北京，1994。
7. Strathmann H., Synthetic Membranes and Their Preparation, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp1.
8．时钧，袁权，高从阶编，膜技术手册，化学工业出版社，北京，2001。
9．王乐夫，《膜工艺》，化学工业出版社，1998，pp15。
10. Porter M.C, Microfiltration, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp.61.
11. Schnbein C., British Patent 11,402 (1846).
12. Sudak R.G, Reverse Osmosis, in Porter M.C (Ed.), Handbook of Industrial Membrane Technology, Noyes Publications, Park Ridge, New Jersey, 1990, pp260.
13. Kesting R.E., Synthetic Polymeric Membranes: A Structure Perspective, 2nd Ed., Wiley-Interscience, New York, 1985, pp134.
14．陈观文，膜科学与技术，19(6)，52(1999)．