论文部分内容阅读
通过控制不同反应时间和邻苯二甲酸酐 壳聚糖的摩尔比制备不同取代度的邻苯二甲酰化壳聚糖(PHCS) .用FTIR研究了反应机理和产物结构 ,观察到PHCS含两类取代即酰胺酸取代和酰亚胺取代 .反应时间较短时主要为前者 ,取代度表示为DS1 ;反应时间较长时主要为后者 ,取代度表示为DS2 .对PHCS在二氯乙酸 (DCA)中的液晶行为观察 ,结果表明 ,PHCS的临界浓度随DS1 的增加而显著增加 .DS1 对PHCS临界浓度的影响明显大于DS2 的影响 .基本上为酰胺酸取代的PHCS的临界浓度高于溶解度 ,以至于观察不到
Phthalylated chitosan (PHCS) with different degrees of substitution was prepared by controlling the reaction time and the molar ratio of phthalic anhydride to chitosan. The reaction mechanism and product structure were investigated by FTIR. Substitution of amido acid and substitution of imide.The reaction time is mainly the former, the degree of substitution is DS1, the latter is the longer when the reaction time is longer, and the degree of substitution is DS2.For PHCS in the presence of dichloroacetic acid DCA). The results showed that the critical concentration of PHCS significantly increased with the increase of DS 1. The effect of DS1 on the critical concentration of PHCS was significantly greater than that of DS2. The critical concentration of PHCS substituted with amido acid was higher than the solubility , So that can not be observed