In this paper, quaternary ammonium salt of chitosan (HACC) was prepared by the reaction of chitosan(CTS) and 2,3-epoxypropyltrimethyl-ammonium chloride(GTA) in isopropanoL The influence factors of the degree of substitution of syn-the tic reaction, such as the molar ratio of reactants, the reaction time, temperature and so on were discussed by single factor experiments. The results showed that the optimal conditions for the preparation were nGta : ncts = 4 : 1, the reaction time 8 h? The reaction temperature 75℃ , the reaction pH value 7* the alkalization time 14 h, the molecular weight of chitosan 3. 2 × 105, the moisture of reaction system 20%. The structures of HACC and CTS were characterized by infrared spectrum, the appearances of morphology of HACC and CTS were researched by scanning electron microscopy, the thermal stabilities of HACC and CTS were studied by thermogravimetry. The results showed that the substitution reaction mainly occurs on the N element, the modified derivatives had significant changes in appearance and size, and lower thermal stability.%采用异丙醇为溶剂,以壳聚糖(CTS)、2,3-环氧丙基三甲基氯化铵(GTA)为原料,用环氧衍生物开环法制备了壳聚糖季铵盐(HACC).通过单因素实验,研究了反应物摩尔比、反应时间、反应温度等因素对产物取代度的影响.结果表明,制备壳聚糖季铵盐的最优工艺为:ncrs∶nGrA =1∶4,反应时间8h,反应温度75℃,反应pH值为7,碱化时间14h,壳聚糖分子量3.2×105,反应体系含水率20％.通过红外光谱、扫描电镜、热重仅对壳聚糖、壳聚糖季铵盐的结构、外观形貌以及热稳定性进行了表征与分析,结果表明壳聚糖季铵化改性以N-取代为主,改性后外貌和粒度有了明显变化,且热稳定性降低.
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