摘要
纤维素葡萄糖单元上的三个羟基几乎完全乙酰化,得到三醋酸纤维素,其取代度为2.9-3.0。三醋酸纤维素水解到取代度2.6─2.4,称为二醋酸纤维素。三醋酸纤维素广泛运用于胶卷、塑料、纺织纤维、膜材料等,而二醋酸纤维素广泛运用于香烟滤嘴和纺织纤维。醋酸纤维素对纤维素的来源有较高的要求,其a-纤维素含量要高于95%,因而能够用于制备醋酸纤维素的原料通常是棉绒和高级木溶解浆,商业上广泛使用的是高级木溶解浆。
竹子具有可再生,低成本的优势,不过到现在为止,还没有竹浆粕用于制备醋酸纤维素的报道。本文选择慈竹为原料,通过结合酸预水解工艺和两道中温硫酸盐蒸煮工艺以及木聚糖酶和DMD用于漂前预处理,制备高a-纤维素含量、高聚合度和高白度的醋化用高级溶解竹浆粕(高级竹浆)。确定了合理的预水解、蒸煮和漂白的工艺条件,研究表明蒸煮过程中适当提高硫化度能够增加脱木素选择性,可以有效防止碳水化合物降解的同时获得深度脱木素的浆粕。在木聚糖酶和DMD处理(包括碱抽提段)阶段,竹浆的白度的增加占整个漂白流程白度增加量的15.29%;卡伯值的降低量占整个漂白流程降低量的37.87%;而特性粘度降低量仅占整个漂白流程降低量13.77%。通过两种处理能够减少纤维素的降解,而能有力地脱除木质素,明显的提高浆粕的白度。红外光谱证明了木聚糖酶对竹浆中半纤维素(木聚糖)的水解作用,而X-衍射分析间接的证明了DMD的脱木素作用,因为2θ角29.4°处归属于无机成分的衍射峰在DMD处理后完全消失。通过X射线光电子能谱(XPS)探测浆粕表面的氧碳原子比(O/C)和四种C原子的相对含量,详细地分析了漂白各阶段浆粕表面化学组成的相对变化,特别是在过氧化氢漂白段,抽提物的含量有明显增加,终漂后浆粕的抽提物表面覆盖率要明显的高于木质素的表面覆盖率。在漂白流程中,DMD处理会降低样品的结晶度和晶粒尺寸,不过其它阶段浆粕的结晶度晶粒尺寸增加,总的说来,最终浆粕的结晶度和晶粒尺寸要高于漂前的。
SEM观察到了制备的高级竹浆表面的裂缝、沟槽和整齐微纤以及内部大大小小的空洞,这表明制浆过程中半纤维素和木质素等非纤维素成分充分去除。分析也表明,与加工烟用醋酸纤维的高级硬木溶解浆(高级木浆)相比,虽然高级竹浆的木聚糖、灰分和抽提物的含量有一些偏高,不过其主要的物理化学指标基本达到了醋化用浆粕的要求。然而相比高级木浆,高级竹浆有较高的结晶度、晶粒尺寸以及更多的氢键,这会影响到后续的反应性能,因而乙酰化之前,必须进行合适的预处理增加醋化反应的可及性。
研究了温度、时间和催化剂用量对高级竹浆的高温乙酰化反应的影响,发现增加温度和提高催化剂的用量均可增加醋酸纤维素的取代度,不过温度对聚合度的影响更为显著。因而我们选择了乙酰化反应采用较低的温度(50℃)相对较高的催化剂用量3%。在预处理方式中,利用醋酸和1%的硫酸活化具有最好的效果,可以保持较高的聚合度而缩短反应时间。高级竹浆直接乙酰化后,反应介质中有一些不溶性残余,这会影响反应溶液的透光度,导致沉淀后的三醋酸纤维素呈现淡黄色。分析表明这些对不溶性残余的形成与溶解性能较差的木聚糖二醋酯(XDA)有关,通过加入少量XDA的良溶剂如1,2-二氯甲烷到高级竹浆的乙酰介质中,能在分子水平溶解这些不溶性残余,而使三醋酸纤维素的白度有了明显的改善,此外,由于溶液中XDA溶解状态的改变,沉淀后产物的结晶度和热性能有了提高。不过高级竹浆直接乙酰化后水解得到的二醋酸纤维素的物理性能如聚合度、白度和丙酮溶液中的颗粒物的测试表明其性能接近商业烟用二醋片,具有较高的质量,这可能是由于木聚糖在高级竹浆中的含量不是很高(3.7%),经过硫酸催化水解后,大部分的XDA会被水解。
TG分析表明三醋酸纤维素的热稳定性要好于二醋酸纤维素,乙酰基的存在能够增加醋酸纤维素的热稳定性;DTA分析显示三醋酸纤维素的熔融峰和分解峰发生了重叠,而二醋酸纤维素因为结晶不完善,晶区分子链和链段可较自由的活动,因而其熔融峰在较低温度出现,拉开了分解峰和熔融峰之间的距离;不过二醋酸纤维素的玻璃化转变区比较明显且Tg高于三醋酸纤维素。
高级竹浆合成的二醋酸纤维素能够顺利纺丝,纤维的拉伸性能也表明其完全适合作为烟用醋酸纤维。其动态力学分析(DMA)显示,除了a转变(玻璃化转变)外,玻璃化温度以下的β~*和γ松弛与纤维的含水有关,而β松弛可能是由主链的局部曲柄运动引起的,不过也不能排除侧基和主链协同运动的可能性。
本文对降解二醋酸纤维的研究表明醋酸纤维在碱处理过程中的重量损失主要是由去乙酰化作用,这种去乙酰化促进了随后的酶降解,当取代度降低到0.8时醋酸纤维的酶降解增加最为显著。~1HNMR分析显示只有在较低氢氧化钠浓度,碱溶液中的去乙酰化反应才与醋酸纤维素三个位置酯基的反应性能有关,但是没有沿着理论上的顺序进行,碱溶液中醋酸纤维脱乙酰化产物的取代度并不均一,而是有一定的分布,这些产物经过纤维素酶处理后,由于类纤维素结构的低取代度的醋酸纤维素的降解,取代度会增加,这也被红外光谱和X衍射对结晶结构的分析所证明。
Cellulose triacetate(CTA)can be used for cellulose acetate(CA)with a degree of substation(DS)above 2.9,which is obtained through acetylation for all three hydroxyl groups of anhydroglucose unit in cellulose.Cellulose diacetate(CDA)with a DS of 2.4-2.6 can be obtained by hydrolysis for CTA.The field of application for CTA includes photographic film base,plastics,textile fiber,membrane materials,and CDA can be used as cigarette filters and textile fiber.Original materials used for preparing cellulose acetate are generally high quality celluloses with an a-cellulose content of more than 95%,therefore,cellulose materials capable of being used for preparing CA are usually cotton linters,as well as high-grade wood dissolving pulps,which are applied in commerce widely.
Bamboo has the advantages of low cost and regeneration,but there is no report about bamboo pulps used in CA preparation.High-grade bamboo dissolving pulp for CA(high-grade bamboo pulp)with a higher a-cellulose content,degree of polymerization(DP)and brightness was prepared in the study through the process flows of acidic prehydrolysis,twice sulphate cook with moderate temperature,and bleaching using pretreatment of xylanase and DMD,and the optimal conditions in these flows was determined.The investigations showed that suitable enhancement of sulfidity can improve selectivity of delignify in cooking and avoid degradation of carbohydrate.The increment of brightness in the stage of xylanase and DMD treatment occupied for 15.29%of the total of the increment in whole bleaching process;the decrease of Kappa number occupied for 37.87%of the total of decrease in whole bleaching process;while the decrease of intrinsic viscosity only occupied for 13.77%the total of decrease in whole bleaching process.Therefore,the two treatments can reduce cellulose degradation,enhance delignification,and improve the brightness of bamboo pulp.Hydrolytic action of xylanase for hemicellulose was demonstrated by FTIR,and X-ray diffraction proved the delignification of DMD for bamboo pulp because of complete disappearance of the diffraction peak at 2θof 29.4(?) attributed to inorganic constituents after DMD treatment.The change of chemical compositions on the surface of bamboo pulps in each stage of bleaching was analyzed in detail by monitoring the ratio of O/C and the contents of four components of C1s indicative of C atoms with 0,1,2 or 3 bonds to neighboring O atom(s).Extractive content on the surface of pulp increased markedly during the stage of H_2O_2 bleaching, and the surface coverage of extractives for the pulp of final bleaching was more than that of lignin.DMD treatment resulted in the decrease of crystallinity and crystallite size of bamboo pulp during bleaching;however,they increased in other stage of bleaching,and on the whole crystallinity and crystallite size of pulp after bleaching were more than these before bleaching.
This entirely removing of lignin and hemicellulose in high-grade bamboo pulp can be seen demonstrated by SEM observation,because of full of grooves,splits, apertures,filaments and fibrils in surfaces of the pulps,and large numbers of apertures and cracks with uneven sizes distributing over the lengthwise section.As compared with high-grade hardwood pulp used for preparing CA,in spite of higher contents of xylan,ash and extractive in high-grade bamboo pulp,its physical and chemical properties came up to the requirement for acetylation;however,the higher crystallinity and crystallite size,as well as more hydrogen bond can affect its reactivity of acetylation.
The influence of temperature,time and catalyst to acetylation of high-grade bamboo pulp was investigated,and found that the increases of both temperature and catalyst could raise the DS of CA,but increasing temperature is more prominent for the decrease of the DP.Therefore,a lower temperature(50℃)and a higher catalyst dosage were adopted in acetylation of high-grade bamboo pulp.Among various pretreatment modes,it was optimal for the activation of the pulp to use acetic acid and 1%sulfuric acid because reactive time of acetylation could be reduced while CA prepared maintained a higher DP.Some insoluble residues remained in acetylation medium of high-grade bamboo pulp,which resulted in the decrease of the transmittance of reaction solution and the brightness of CTA prepared. Characterization of the insoluble residue indicated that its formation was associated with XDA,which has poor solubility in acetylation medium,An addition of good solvent of XDA such as 1,2-dichloroethane to acetylation medium of high-grade bamboo pulp could release the aggregation of XDA and CTA and dissolve the insoluble residue,which led to the improves of the properties of CTA prepared such as brightness,crystallinity and thermal stability.However,measuring the properties such brightness,DP and particles in acetone for CDA prepared by acetylation and subsequent hydrolysis for high-grade bamboo pulp,indicated that it had high quality and had access to commercial CDA for cigarette filter because of a lower content of xylan in high-grade bamboo pulp(3.7%),most of which can be hydrolyzed by sulfuric acid catalysis.
TG analysis indicated that thermal stability of CTA was more than that of CDA and the existence of acetyl group could improve thermal property of CA.The two peaks corresponding to crystallization and melting overlapped in DTA curve of CTA,while owing to less perfect and smaller crystallites in CDA,more facile motility for the molecule chains or chain segment within its crystalline region resulted in the melting peak appearing in a lower temperature,and the interval between the melting and decomposition temperature enlarged,accordingly;on the other hand as compared with CTA,the peak corresponding to gamma transition for CDA was more conspicuous and Tg appeared in a higher temperature.
CDA prepared from high-grade bamboo pulp could be spinned favorably,and tensile properties of the CDA fibers spinned indicated of suitability for cigarette filter. DMA of the fibers demonstrated that a-relaxation was related to the glass-to-rubber transition;theβ~* shoulder was due to loss of moisture;theβrelaxation is tentatively assigned to local motions of the main chain(glucose unit);the low-temperatureγrelaxation was humidity-dependent.
The study on degradation of CDA fibers showed that weight loss of CA fibers immersed in NaOH solution chiefly depended on acetylation,and alkaline treatment promoted the degradation of CA fibers in cellulase solution by reason of deacetylation,especially when DS of CA fibers reached 0.8,cellulase degradation increased most markedly.~1NMR spectra suggested that only in a lower NaOH concentration(=0.25 N)deacetylation reaction was affected by the reactivities of ester groups at position 2,3 and 6 in anhydroglucose unit,but did not follow the theoretical trend in the three positions.Moreover,the DS for polymer molecules in CA fibers were dispersive after alkaline treatment in heterogeneous condition and the DS of the product increased during sequent cellulase degradation.This was also demonstrated by the result of IR analysis and X-ray diffraction.
引文
[1]高洁,汤烈贵.高分子科学丛书.北京:科学出版社,1996.
[2]梅洁,陈家楠,欧义芳.醋酸纤维素的现状与发展趋势.纤维素科学与技术,1999,7(4):56-62.
[3]高春红.烟用二醋酸纤维工业进展.烟草科技/烟草工艺,1999,138(5):9-11.
[4]Paul Rustemeyer.History of CA and Evolution of the Markets.Macromol Symp,2004,208,1-6.
[5]魏春学.对发展我国醋酸纤维工业的分析及建议.中国纺织,2002,19:19-21.
[6]郑宝山.我国烟用丝束的现状与发展.现代化工,1999,19(2):37-38.
[7]张勇,王海峰,范红艳.我国烟用纤维丝束市场展望.新疆化工,2001,(1):10-11.
[8]Shiro Saka,Hiroyuki Matsumura.Wood Pulp Manufacturing and Quality Characteristics.Macromol Symp,2004,208,41-48.
[9]梅洁,欧义芳,陈家楠.醋酸纤维素的高温合成及其性质的研究.纤维素科学与技术,2000,8(1):8-16.
[10]Rowell R.M,A.M.Tillman,Z.Liu.Dimensional stabilization of flakeboard by chemical modification.Wood Sci.Technol.,1986,20,83-95.
[11]Rowell R.M,R.Simonson,A.M.Tillman.A simplified procedure for the acetylation of chips for dimensionally stabilized particle board products.Paperi ja puu,1986,68,740-744.
[12]Rowell R.M,J.A.Youngquist,J.A.Hyatt.Dimensional stability of aspen fiberboard made from acetylated fiber.Wood Fiber Sci,1991,23,558-566.
[13]Barkalow D.G,R.M.Rowell,R.A.Young.A new approach for the production of cellulose acetate:Acetylation of mechanical pulp with subsequent isolation of cellulose acetate by differential solubility.J Appl Polym Sci.,1989,37,1009-1018.
[14]Efanov,M.V.Cellulose esters prepared by wood esterification.Chem.Natural Compounds,2001,37,76-79.
[15]Rowell R.M,A.M.Tillman,R.Simonson.Vapor-phase acetylation of aspen wood flakes.J.Wood Chem.Technol.,1986,6,293-309.
[16]梅洁,陈家楠,欧义芳.气-固相反应制备醋酸纤维素.纤维素科学与技术,2001,9(1):45-49.
[17]B.Philipp,W.Wagenknecht,I.Nelits.第二次全国纤维素科学与技术会议论文预印本.广州,1988,p16.
[18]E.Husemann,E.Siefert.Macromol.Chem,1969,128,288.
[19]C.Deus,H.Friebolin,E.Siefert.Partiell acetylierte cellulose:Synthese und bestimmung der substituentenverteilung mit hilfe der 1H NMR-spektroskopie.Macromol.Chem,1991,192,75.
[20]Burkart Philipp.Organic Solvents for Cellulose.Polymer News,1990,15,170-175.
[21]C.L.McCormick,P.A.Callais.Derivatization of cellulose in lithium chloride and N-N-dimethylacetamide solutions.Polymer,1987,27,2435.
[22]O.A.El Seoud,G.Marson,G.T.Ciacco,E.Frollini.An efficient,one-pot acetylation of cellulose under homogeneous reaction conditions.Macromol.Chem.Phys.,2000,201,882.
[23]A.M.Regiani,E.Frollini,G.Marson,O.A.El Seoud.Some aspects of acylation of cellulose under homogeneous solution conditions.J.Polym.Sci.,Part A:Polym.Chem.1999,37,1357.
[24]S.Fischer,W.Voigt,K.Fischer.The behaviour of cellulose in hydrated melts of the composition LiXcn H2O(X=I-,NO3-,CH3COO-,Clo4-)Cellulose,1999,6,213.
[25]S.Fischer,H.Leipner,E.Brendler,W.Voigt.Structural changes of cellulose dissolved in molten salt hydrates.Macromol.Chem.Phys,2000,201,1041.
[26]D.C.Johnson,M.D.Nicholson,F.C.Haigh.Dissolution and reaction of cellulose in homogeneous conditions.Appl.Polym.Symp.,1976,28,931.
[27]T.J.Baker,L.R.Schroeder,D.C.Johnson.Formation of methylol cellulose and its dissolution in polar aprotic solvents.Cellul Chem Technol,1981,15,311.
[28]B.N.Salin,M.Cemeris,D.P.Mironov,A.G.Zatsepin.Trifluoroacetic acid as solvent for the synthesis of cellulose esters─1:synthesis of triesters of cellulose and aliphatic carboxylic acids.Khim Drev,1991,65-69.
[29]B.N.Salin,M.Cemeris,O.L.Malikova.Trifluoroacetic acid as a solvent for the synthesis of cellulose esters─3:synthesis of mixed cellulose esters.Khim Drev,1993,3-7.
[30]Th.Henze,R.Dicke,A.Koschella,A.H.Kull,E.A.Klohr,W.Koch.Effective preparation of cellulose derivatives in a new simple cellulose solvent.Macromol.Chem.Phys,2000,201,627.
[31]Funaki Y,Ueda K,Saka S,Soejima S.Characterization of cellulose acetate in acetone solution-Studies on prehump-Ⅱ in GPC pattern.Journal of Applied Polymer Science,1993,48,419-424.
[32]Neal,J.L.Factors affecting the solution properties of cellulose acetate.Journal of Applied Polymer Science,1965,9,947-961.
[33]Saka S.,Takanashi K,Matsumara H.Effects of solvent addition to acetylation medium on cellulose triacetate prepared from low-grade hardwood dissolving pulp.Journal of Applied Polymer Science,1998,69,1445-1449.
[34]Saka S,Ohmae K.Thermal properties of cellulose triacetate as prepared from low-grade dissolving pulp.Journal of Applied Polymer Science,1996,62,1003-1010.
[35]Saka S,Takanashi K.Cellulose triacetate prepared from low-grade hardwood dissolving pulp and its insoluble residues in acetylation mediums.Journal of Applied Polymer Science,1998,67,289-297.
[36]Shashidhara G.M,Guruprasad k.H.Effect of concentrated sulfuric acid and nitroethane on insoluble residues in acetylating medium of cellulose acetate prepared from low grade pulps.Journal of Applied Polymer Science,2005,98,1765-1771.
[37]Biswas A.,Saha B.C,Lawton J,Shogren R.L,Willett J.L.Process for obtaining cellulose acetate from agricultural by-products.Carbohydrate Polymers,2006,64,134-137.
[38]马晓龙,沈琳,杨占平,曹建华.国产木浆合成烟用醋酸纤维素的研究.合成纤维,2004,5:9-12.
[39]潘燕如,邹君,曾胜.标木研制烟用二醋酸纤维.广西化纤通讯,1996,(2):3-11.
[40]蔡明德,汪国荣,王松雪.国外纸业用竹近况.竹子研究汇刊,1992,11(2):66-88.
[41]叶诚生,王幸祥.竹类资源的综合利用.上海:上海科学技术文献出版社,1988,43-46.
[42]Kazuya Okubo,Toru Fujii,Yuzo Yamamoto.Development of bamboo-based polymer composites and their mechanical properties.Composites:Part A 2004,35,377.
[43]邹超贤.开发竹子人纤浆粕,促进竹子产业化发展.广西化纤通讯,2003,(2):19.
[44]S.H.L,Q.Y.Zeng,Y.L.Xiao et al.Biomimicry of' bamboo bast fiber with engineering composite materials.Materials Science and Engineering:C3,1995,125-130.
[45]G.A.斯穆克著.制浆造纸工程大全.北京:中国轻工业出版社,2001,5.
[46]谢来苏等主编.制浆原理与工程.北京:中国轻工业出版社,2001,5.
[47]陈华馥.硫酸盐法竹浆二氧化氯漂白的实验.上海造纸,2000,33(2):10.
[48]赖玉荣,张曾,黄干强.木素在过氧化氢漂白条件下的反应.中国造纸学报,2005,20(2):203-207.
[49]曲丽君,管云玲,郭肖青.黄麻碱氧─浴一步法脱胶漂白短流程工艺.青岛大学学报:工程技术版,2003,18(1):40-43.
[50]Clark T,Steward D,Bruce M.E.Improved bleachability of radiate pinekraft pulps following treatment with hemicellulolitic enzymes.Appita J,1991,44,389.
[51]Kantelinen A,Hortling B,Sundquist.Proposed mechanism of enzymatic bleaching of kraft pulp with xylanase.Holzforschung,1993,47,318.
[52]Senior D.J,Harmilton J.Biobleaching with xylanases brings biotechnology to reality.Pulp and Paper,1992,66,11.
[53]Vu T.H.M,Pakkanen H,Alen R.Delignification of bamboo(Bambusa procera acher)Part 1.Kraft pulping and the subsequent oxygen delignification to pulp with a low kappa number.Industrial Crops and Products,2004,19,49-57.
[54]Thwe M.M,Liao K.Durability of bamboo-glass fiber reinforced polymer matrix hybrid composites.Composites Science and Technology,2003,63,375-387.
[55]Hanafi Ismail,M.R Edyham,B.Wirjosentono.Bamboo fibre filled natural rubber composites:the effects of filler loading and bonding agent.Polymer Testing,2002,21,139-144.
[56]胡惠仁,石淑兰,魏德津.四种竹材硫酸盐法制浆的比较.天津造纸,1999,4:2-8.
[57]段经奎,张善荣,马迎松,岳建冬,徐琼波.景洪竹子硫酸盐法制浆性能的研究.西南造纸,2006,35(4):4-8.
[58]沈望浩,陈夏生.竹纤维的粘胶竹浆粕生产技术及其纺织品.合成纤维,2003,6:37-39.
[59]黄楚和.一种可溶解竹浆的制造方法:CN1693581[P].2005-11-09.
[60]沈望浩,陈夏生.粘胶纤维用竹浆粕生产新途径──试论二步法变性蒸煮新工艺.上海造纸,2002,33(7):4-7.
[61]LEE,Kwon-Hyok,WON.Jong-Myoung.Process for producing fiber pulp utilizing bamboo and pulp produced using the same.[P]WO/2006/115310.2006-11-02.
[1]G.A.斯穆克著.制浆造纸工程大全.北京:中国轻工业出版社,2001,5.
[2]黄楚和.一种可溶解竹浆的制造方法:CN1693581[P].2005-11-09.
[3]沈望浩,陈夏生.粘胶纤维用竹浆粕生产新途径──试论二步法变性蒸煮新工艺.上海造纸,2002,33(7):4-7.
[4]隆言泉主编.制浆造纸工艺学.北京:中国轻工业出版社,1987:135-139.
[5]Montgomery R E.Catalysis of peroxymonosulfate reactions by ketone.Amer Chem Soc,1974,96,7820-7821.
[6]谢来苏等主编.制浆原理与工程.北京:中国轻工业出版社,2001,5.
[7]Dimmel D.R,Shepara D.Studies on the Mechanism of Action of Anthraquinone as a Pulping catalyst.Canadian Wood Chemistry Symposium(Niagara Falls),1982,29.
[8]G.Ge! lerstedt,J.Pranda,E.-L.Linfors.Structural and Molecular Properties of Residual Birch Kraft Lignins.Journal of Wood Chemistry and Technology,1994,14,467-482.
[9]Chiang V.L,Funaoka M.The formation and quantity of diphenylmethane type structures in residual lignin during Kraft delignification of Douglas-fir.Holzforschung,1988,42,385.
[10]Adam W,Curci R,Edwards J.O.Dioxiranes:A New Class of Powerful Oxidants.Accounts of Chemical Research,1989,22,205.
[11]Baumstark A.L,Vasquez,P.C.Epoxidation by dimethyldioxirane.Electronic and steric effects.J.Org.Chem.,1988,53,3437.
[12]Baertschi S.W,Raney K.D,Stone M.P,Harris T.M.Preparation of the 8,9-epoxide of the mycotoxin aflatoxin B1:the ultimate carcinogenic species.J.Am.Chem.Soc.,1988,110,7929.
[13]Adam W,Schonberger A.Dimethyldioxirane Oxidation of Hydroquinones into Quinones and 2,3-Dihydroxycyclohexene-1,4-diones.Tetrahedron Lett.,1992,33,53-56.
[14]Crandall J.K,Zucco M,Kirsch R.S,Coppert D.M.Tetrahedron Lett.,1991,32,5443.
[15]Marples B.A,Muxworthy J.P,Baggaley K.H.Oxidative Cleavage of Benzyl Ethers Using Dimethyldioxirane.Synlett,1992,8,646.
[16]Ragauskas A.J.Bleaching of Kraft Pulps via Dioxiranes.IPST Technical Paper Series Number 518,1994.
[17]Dushin R.G,Danishefsky s.J.Stereospecific synthesis of aryl β-glucosides:an application to the synthesis of a prototype corresponding to the aryloxy carbohydrate domain of vancomycin.J.Am.Chem.Soc.,1992,114,3471.
[18]石淑兰.制浆造纸分析与检测.北京:中国轻工业出版社,2003.
[19]Segal L,Creely L,Martin A.E.An empirical method for estimating the degree of crystallinity of native cellulose using X-ray diffractometer.Textiles Research Journal,1959,29,786-794.
[20]Ahtee M,Hattula T,Mangs J,Paakkari T.An X-ray diffraction method for determination of crystallinity of wood pulp.Paperi Ja Puu,1988,8,475-480。
[21]T.E.Timell.Recent progress in the chemistry of wood hemicelluloses.Wood Sci Technol 1967,1,45.
[22]Andreeva Q.A,Burkova L.A,Grebenkin A.N,Grebenkin A.A.IR spectroscopic study of prepurified flax.Russian Journal of Applied Chemistry,2002,75,1513-1516.
[23]李友明.硫化度对RDH蒸煮脱木素选择性的影响.中国造纸学报,1999,14:1-5.
[24]M.B.Roncero,A.L.Torres,J.F.Colom,T.Vidal.TCF bleaching of wheat straw pulp using ozone and xylanase.Part A:paper quality assessment.Bioresource Technology,2003,87,305-314.
[25]周学飞.硫酸盐浆聚糖酶一过氧化氢生物漂白研究.西南造低,2003,32(5):23-25.
[26]M.Blanca Roncero,Antonio L,Tones Teresa Vidal.The effect of xylanase on lignocellulosic components during the bleaching of wood pulps.Bioresource Technology,2005,96,21-30.
[27]J Laine,P Stenius.Surface characterization of unbleached kraft pulps by means of ESCA.Cellulose,1994,1,145-160.
[28]Dorrls G.M,Gray D.G.The Surface Analysis of Paper and Wood Fiber by ESCA.1.Application to Cellulose and Lignin.Cellulose Chem.Technol.1978,12,9-23.
[29]Johansson L-S,Campbell J.M,Koljonen K,Stenius P.Evaluation of surface lignin on cellulose fibers with XPS.Appl Surf Sci,1999,144,145,92-95.
[30]Allen LH,Lapointe CL.Physical distribution of resin in bleached kraft pulp mills.73rd Annual Meeting CPPA,Montreal,Techn.Sec.,Preprints B 1987,pp.B331-339.
[31]Strom G,Carlsson G.Wettability of kraft pulps-effect of surface composition and oxygen plasma treatment.J Adhes Sci Technol,1992,6,745.
[32]Johanna Gustafsson,Laura Ciovica,Jouko Peltonen.The ultrastructure of spruce kraft pulps studied by atomic force microscopy(AFM)and X-ray photoelectron spectroscopy(XPS).Polymer,2003,44,661-670.
[33]Laine J,Stenius P.Effect of ECF and TCF bleaching on the surface chemical composition of kraft pulp as determined by ESCA.Nord Pulp Pap Res J,1996,3,201.
[34]Gumuskaya E,Usta M,Kirci H.The effects of various pulping conditions on crystalline structure of cellulose in cotton linters.Polymer Degradation and Stability,2003,81,559-564.
[1]石淑兰.制浆造纸分析与检测.北京:中国轻工业出版社,2003.
[2]B.Focher,M.T.Palma,M.Canetti,G.Torri,c.Cosentino,G.Gastaldi.Structural differences between non-wood plant celluloses:evidence from solid state NMR,vibrational spectroscopy and X-ray diffractometry.Ind Crops Prod,2001,13,193.
[3]Shiro Saka,Hiroyuki Matsumura.Wood Pulp Manufacturing and Quality Characteristics.Macromol Symp,2004,208,41-48.
[4]Neal,J.L.Factors affecting the solution properties of cellulose acetate.Journal of Applied Polymer Science,1965,9,947-961.
[5]Funaki Y,Ueda K,Saka S,Soejima S.Characterization of cellulose acetate in acetone solution-Studies on prehump-Ⅱ in GPC pattern.Journal of Applied Polymer Science,1993,48,419-424.
[6]Ritcher U,Krause T,Schempp W.Untersuchungen zur Alkalibehandlung von Cellulosefasern.Teil 1.Infrarot spectroskopische und rontgenographische Beurteiliung der Anderung des Ordnungszustandes.Angew Macromolecular Chemistry,1991,1851186,155-167.
[7]Ouajai S,Shanks R.A.Composition,structure and thermal degradation of hemp cellulose after chemical treatments.Polymer Degradation and Stability,2005,89,327-335.
[8]Oh S.Y,Yoo D.I,Shin Y,Kim H.C.Crystalline structure analysis of cellulose treated with sodium hydroxide and carbon dioxide by means of X-ray diffraction and FTIR spectroscopy.Carbohydrate Research,2005,340,2376-2391.
[9]K.H.Gardner,J.Blackwell.Hydrogen.bonding in native cellulose.Biochim.Biophys.Acta,1974,343,232.
[10]T.Kondo.The assignment of IR absorption bands due to free hydroxyl groups in cellulose.Cellulose,1997,4,281-292.
[11]Y.Marechal,H.Chanzy.The hydrogen bond network.in Iβ cellulose as observed by infrared spectrometry.Journal of Molecular Structure,2000,523,183-196.
[12]S.Kokot,B.Czarnik-Matusewicz,Y.Ozaki.Two Dimensional Correlation Spectroscopy and Principal Component Analysis Studies of Temperature Dependent Infrared Spectra of Cotton-Cellulose.Biopolymers,2002,67,456.
[13]J.Sugiyama,J.Persson,H.Chanzy.Combined infrared and electron diffraction study of the polymorphism of native cellulose.Macromolecules,1991,24,2461.
[14]Mary L,Nelson.Relation of certain infrared bands to cellulose crystallinity and crystal lattice type.Part II.A new infrared ratio for estimation of crystallinity in celluloses I and II.Journal of Applied Polymer Science,1964,8,1325-1341.
[15]Maunu S,Liitia T,Kauliomaki S,et al.~(13)C CPMAS NMR investigations of cellulose polymorphs in different pulps.Cellulose,2000,7,147-159.
[16]Rondeau-Mouroa C,Bouchet B,Pontoire B,Robert P,Mazoyer J,Buleon A.Structural features and potential texturising properties of lemon and maize cellulose microfibrils.Carbohydrate Polymers,2003,53,241-252.
[17]Wickholm K,Larsson P.T,Iversen T.Assignment of non-crystalline forms in cellulose I by CP/MAS ~(13)C NMR spectroscopy.Carbohydrate Research,1998,312,123-129.
[18]Larsson P.T,Wickholm K,Iversen T.A CP/MAS ~(13)C NMR investigation of molecular ordering in celluloses,Carbohydrate Research,1997,302,19-25.
[19]Atalla R.H,VanderHart D.L.The role of solid state ~(13)C NMR spectroscopy in studies of the nature of native celluloses.Solid State Nuclear Magnetic Resonance,1999,15,1-19.
[20]Larsson P.T,Hult E.L,Wickholm K,Pettersson E,Iversen T.CP/MAS ~(13)C-NMR spectroscopy applied to structure and interaction studies on cellulose I.Solid State Nuclear Magnetic Resonance,1999,15,31-40.
[21]Larsson P.T,Westermark U,Iversen T.Determination of the cellulose I_a allomorph content in a tunicate cellulose by CP/MAS ~(13)C-NMR spectroscopy.Carbohydrate Research,1995,278,339-343.
[1]Neal J.L.Factors affecting the solution properties of cellulose acetate.Journal of Applied Polymer Science,1965,9,947-961.
[2]Funaki Y,Ueda K,Saka S,Soejima S.Characterization of cellulose acetate in acetone solution-Studies on prehump-Ⅱ in GPC pattern.Journal of Applied Polymer Science,1993,48,419-424.
[3]Barkalow D.G,R.M Rowell,R.A Young.A new approach for the production of cellulose acetate:Acetylation of mechanical pulp with subsequent isolation of cellulose acetate by differential solubility.J Appl Polym Sci.,1989,37,1009-1018.
[4]Efanov M.V.Cellulose esters prepared by wood esterification.Chem.Natural Compounds,2001,37,76-79.
[5]Saka S,Takanashi K,Matsumara H.Effects of solvent addition to acetylation medium on cellulose triacetate prepared from low-grade hardwood dissolving pulp.Journal of Applied Polymer Science,1998,69,1445-1449.
[6]Saka S,Ohmae K.Thermal properties of cellulose triacetate as prepared from low-grade dissolving pulp.Journal of Applied Polymer Science,1996,62,1003-1010.
[7]Saka S,Takanashi K.Cellulose triacetate prepared from low-grade hardwood dissolving pulp and its insoluble residues in acetylation mediums.Journal of Applied Polymer Science,1998,67,289-297.
[8]高洁,汤烈贵.纤维素科学.北京:科学出版社,1996.
[9]梅洁,欧义芳,陈家楠.醋酸纤维素取代基分布与性质的关系.纤维素科学与技术,2002,10(1):12-19.
[10]梅洁,欧义芳,陈家楠.醋酸纤维素的高温合成及其性质的研究.纤维素科学与技术,2000,8(1):8-16.
[11]RoyL Whistler.Methods In Carbohydrate Chemistry.New York:Academic Press,1963,3:21。
[12]Hans Steinmeier.Acetate manufacturing,process and technology.Macromol.Symp,2004,208,49-60.
[13]Miyamoto T,Sato Y,Shibata T.~(13)C-NMR spectral studies on the distribution of substituents in water-soluble cellulose acetate.J.Polym.Sci.,Part A:Chem.Ed.,1985,23,1373.
[14]Gardner P.E,Chang,M.Y.The acetylation of native and modified hemicelluloses.TAPPI,1974,57,71-75.
[15]坂志朗,松村裕之.生产酯酸纤维素酯的方法:CN 93106682[P].1994-12-07.
[16]Shashidhara G.M,Guruprasad K.H.Effect of concentrated sulfuric acid and nitroethane on insoluble residues in acetylating medium of cellulose acetate prepared from low grade pulps.Journal of Applied Polymer Science,2005,98,1765-1771.
[17]Ryskina I,Fedorova I.Y.Electron microscopy and X-ray diffraction study of structuralization in acetylation of cellulose.Polymer Science,1986,28,680-685.
[18]Kamide K,Saito M.Thermal analysis of cellulose acetate solids with total degrees of substitution of 0.49,1.75,2.46,and 2.92.Polymer journal,1985,17,919-928.
[1]Akihiko Watanabe,Shigeaki Morita,et al.Drying process of microcrystalline cellulose studied by attenuated total reflection IR spectroscopy with two-dimensional correlationspectroscopy and principal component analysis.Journal of Molecular Structure,2006,799,102-110.
[2]M.O.Adebajo,R.L.Frost,J.T.Kloprogge,S.Kokot.Raman spectroscopic investigation of acetylation of raw cotton.Spectrochimica Acta Part A,2006,64,448-453.
[3]高洁,汤烈贵.纤维素科学.北京:科学出版社,1996.
[4]Mei-rong Huang,Xin-Gui Li.Thermal degradation of cellulose and cellulose esters.Journal of Applied Polymer Science,68,293-304.
[5]Freeman ES,Carroll BT.Journal of Physical Chemistry,1958,62,394.
[6]Kamide K,Saito M.Thermal analysis of cellulose acetate solids with total degrees of substitution of 0.49,1.75,2.46,and 2.92.Polymer journal,1985,17,919-928.
[7]梅洁,欧义芳,陈家楠.醋酸纤维素取代基分布与性质的关系.纤维素科学与技术,2002,10(1):12-19.
[8]Zugenmaier,P.Characteristics of cellulose acetates.Macromol.Symp 2004,208,81.
[9]何曼君,陈维孝,董西侠.高分子物理.上海:复旦大学出版社,1990.10.
[10]杨明山,Shukbai Irida,杨利庭,金目光.新型再生纤维素纤维的动态粘弹性能研究.纤 维素科学与技术,1999,7(3):1-5.
[11]Jun Tanaka,Fumio Himematsu.Polyester fiber and method of manufacturing the same.USP5558935[P].1996-9-24.
[12]M.Scandola,G.Ceccorulli.Viscoelastic properties of cellulose derivatives:1.Cellulose acetate.Polymer,1985,26,1953.
[13]杨明山,Shukbai Irida,杨利庭,金日光.从动态粘弹性能来分析两种再生纤维素纤维的结构差异研究.化学与粘合,2000,1:1-3.
[1]Buchanan C.M,Edgar K.J,Hyatt J.A,Wilson A.K.Preparation of cellulose[1-C-13]acetates and determination of monomer composition by NMR spectroscopy.Macromolecules,1991,24,3050.
[2]Zugenmaier,P.Characteristics of cellulose acetates.Macromol.Symp,2004,208,81.
[3]Reese,E.T.Biological degradation of cellulose derivatives.Ind.Eng.Chem.,1957,49,89.
[4]Moriyoshi K,Ohmoto T,Ohe T,Sakai K.Purification and Characterization of an Endo-1,4-β-glucanase from Neisseria sicca SB that Hydrolyzes β-1,4 Linkages in Cellulose Acetate.Biosci Biotechnol Biochem,2002,66,508.
[5]Moriyoshi K,Ohmoto T,Ohe T,Sakai K.Mode of Action on Deacetylation of Acetylated Methyl Glycoside by Cellulose Acetate Esterase from Neisseria sicca SB.Biosci Biotechnol Biochem,2005,69,1292.
[6]Ishigaki T,Sugano W,Ike M,Fujita M.Enzymatic Degradation of Cellulose Acetate Plastic by Novel Degrading Bacterium Bacillus sp.S2055.J Biosci Bioeng,2000,90,400.
[7]Ishigaki T,Kawagoshi Y,Ike M,Fujita M.Biodegradation of polyvinyl alcohol-starch blenf plastic film.World J Microbiol Biotechnol,1999,15,321.
[8]Komarek R.J,Gardner R.M,Buchanan C.M,Gedon S.Biodegradation of radiolabeled cellulose acetate and cellulose propionate.J Appl Polym Sci,1993,50,1739.
[9]Gu J.D,Eberiel D.T,McCarthy S.P,Gross R.A.Degradation and mineralization of cellulose acetate in simulated thermophilic compost environments.J Environ Polym Degrad,1993,1,281.
[10]Yamashita Y,Endo T.Deterioration behavior of cellulose acetate films in acidic or basic aqueous solutions.J Appl Polym Sci,2004,91,3354.
[11]De Bordenave J.F,Bringardner D.J.Textile World,1956,106,112.
[12] Yamashita Y, Endo T. Deacetylation behavior of binary blend films of cellulose acetate and various polymers. J Appl Polym Sci, 2006,100,1816.
[13] Miyamoto T, Sato Y, Shibata T. ~(13)C-NMR spectral studies on the distribution of substituents in water-soluble cellulose acetate. J. Polym. Sci., Part A: Chem. Ed., 1985,23,1373.
[14] Isogai, A. Material Science of Cellulose, University of Tokyo Press: Tokyo, 2001.
[15] Holmes P.A. Applications of PHB-a microbially produced biodegradable thermoplastic. Phys Technol, 1985,16,32.
[16] Goodlett V.W, Dougherty J.T, Patton H.W. Characterization of cellulose acetates by nuclear magnetic resonance. J Polym Sci: Part A-1 1971, 9,155.
[17] Kamide K, Okajima K, Saito M. Determination of Distribution of O-Acetyl Group in Trihydric Alcohol Units of Cellulose Acetate by ~(13)C-NMR Analysis. Polym J, 1981,13,115.
[18] Doyle S, Pethrick RA, Harris R.K, Lane J.M, Packer KJ, Heatley F. ~(13)C nuclear magnetic resonance studies of cellulose acetate in the solution and solid states. Polymer, 1986,27,19.
[19] Samios E, Dart R.K, Dawkins J.V. Preparation, characterization and biodegradation studies on cellulose acetates with varying degrees of substitution. Polymer, 1997,38,3045.
[20] Wiley J.H, Atalla R.H. Bands assignments in the Raman spectra of celluloses. Carbohydr Res, 1987,160,113.
[21] M.O. Adebajo, R.L. Frost, J.T. Kloprogge, S. Kokot. Raman spectroscopic investigation of acetylation of raw cotton. Spectrochimica Acta Part A, 2006,64,448-453.