两性纤维素接枝共聚物CGD的研究 Ⅱ水溶液的性质  

Studies on Amphoteric Cellulosic Graft Copolymer CGD II Property of its Aqueous Solution

作　　者：谭业邦[1] 张黎明[1] 李卓美[1] 

机构地区：[1]中山大学高分子研究所

出　　处：《功能高分子学报》1999年第3期258-262,共5页Journal of Functional Polymers

基　　金：中科院纤维素化学开放实验室;高分子材料工程国家重点实验室基金;广东省自然科学基金

摘　　要：用浊度法研究了一系列不同结构特征的羧甲基纤维素接枝甲基丙烯酸二甲胺基乙酯两性共聚物（ＣＧＤ） 的溶解性及其组成和等电点的关系；用粘度法研究了ＣＧＤ 水溶液的流体力学性质，考察了聚合物浓度、温度、外加无机盐和ｐＨ 对溶液流体力学性质的影响。研究发现ＣＧＤ 具有明显的等电点，且与组成有关，即随着阳离子链节含量的增加，等电点移向高ｐＨ 值，外加盐能提高ＣＧＤ 的溶解性；ＣＧＤ 溶液的粘度随盐浓度变化出现最大值，与单一电荷的聚电解质不同，且随着ｐＨ 的变化出现最低点，进一步表明了ＣＧＤ 具有两性聚合物的特征；ＣＧＤ 溶液在纤维素酶存在下发生降解。The solution properties of the cellulosic graft copolymer CGD were studied by viscosity and turbidity methods. It was found that copolymers had the characteristics of an amphoteric polymer, and their solution properties were dependent on their structures and composition. CGD was water insoluble at the isoelectric point (IEP), but became water soluble at the pH lower or higher than IEP. The presence of salt could improve the solubility of CGD, and the ability to dissolve the copolymer was related to the type and concentration of the salt. The reduced viscosity η sp /C of CGD in salt solution in different pH showed minima indicating that it had the IEP. The changes of η sp /C for CGD solution were also studied under different conditions, such as temperature, the concentration of salt. Meanwhile the copolymer in aqueous solution could degrade in the presence of cellulose enzyme.

关 键 词：CGD 共聚物 纤维素 两性聚合物 溶解性 等电点 

分 类 号：O636.11[理学—高分子化学]