甲壳素类液晶高分子的研究Ⅱ-侧基长度和取代度对羧酰化壳聚糖的液晶性的影响  

STUDIES ON CHITIN\|BASED LIQUID CRYSTALLINE POLYMERS Ⅱ INFLUENCE OF SIDE CHAIN LENGTH AND SUBSTITUTION DEGREE ON THE LIQUID CRYSTALLINE BEHAVIOR OF ACYLATED CHITOSANS

作　　者：董炎明[1] 汪剑炜[1] 梅雪峰[1] 吴智福 袁清[1] 刘晃南 

机构地区：[1]厦门大学材料科学系,厦门361005

出　　处：《高分子学报》1999年第6期668-673,共6页Acta Polymerica Sinica

基　　金：中国科学院纤维素化学开放研究实验室资助

摘　　要：五种羧酰化壳聚糖即乙酰化、丙酰化、丁酰化、己酰化和庚酰化壳聚糖在二氯乙酸溶液中均呈现胆甾型溶致液晶相．临界浓度随侧基长度的增加而增加，但取代度（ 从０－２１ 变化到０－９４） 对临界浓度没有影响．在两相共存浓度区内，均呈现典型的滴状织构．从两相共存到完全液晶相的转变浓度也随侧基长度的增加而增加．Methanesulfonic acid method was used to synthesize five acylated chitosans,i.e.acetyl chitosan,propionyl chitosan,butyryl chitosan,hexanoyl chitosan and heptanoyl chitosan.All derivatives demonstrated lyotropic liquid crystalline behavior.Cholesteric phase was shown by the presence of fingerprint textures.Substitution degree of propionyl chitosan in the range from 0\^21 to 0\^94 had no obvious effect on the critical concentration,because a small substitution degree such as 0\^21 is large enough to destroy most of the hydrogen band of inter\|and\|intra\|molecules.But the critical concentration(\%W/W\%)increased from 0\^15 to 0\^22,as the side chain length increased.This phenomenon can be explained by the drop of the rigidity of the chain.Typical droplet texture appeared in the biphase coexistence concentration region of all five acylated chitosans.The transition concentration from biphase coexistence to mesophase was also affected by the side chain length.Acylated chitosans were all water soluble and exhibited lyotropic liquid crystalline behavior in water.

关 键 词：壳聚糖 羧酰化壳聚糖 溶致液晶 

分 类 号：O636.1[理学—高分子化学] O753.2[理学—化学]