细菌纤维素乙酰化改性研究

Acetylation modification of bacterial cellulose

以细菌纤维素为原料,浓硫酸为催化剂,与醋酸酐进行乙酰化反应,制得醋酸细菌纤维素(BCA),讨论了反应温度、反应时间、固液比、催化剂的用量对合成BCA的影响。结果表明:细菌纤维素的羟基被乙酰基取代。适宜的反应条件为反应温度70℃,反应时间2.5 h,细菌纤维素为1.0 g时,醋酸酐用量为20mL,催化剂浓硫酸用量为0.1 mL,BCA产率可达98%以上,取代度达2.9以上。

Bacterial cellulose and acetic anhydride were acetylated with concentrated sulfuric acid as catalyst to produce acid bacterial cellulose（BCA）. The effects of reaction temperature and time, solid-liquid ratio and catalyst amount on thesynthesis of BCA were discussed. The results showed that acetyl group was substituted for hydroxyl group in bacterial cellulose. The BCA out- put can be above 98% and the substitution degree above 2.9 when the reaction conditions were optimized as followed： reaction temperature 70℃ and time 2.5 h, 20 mL acetic anhydride in 1.0 g bacterial cellulose and catalyst amount 0.1 mL.