没食子酸微晶纤维素酯的合成工艺研究

用可再生资源微晶纤维素为原料,在催化剂的作用下,与含抗氧化基团的没食子酸作用,合成一种新型没食子酸酯。考察了对甲苯磺酸、十二烷基苯磺酸、磷钨酸三种催化剂对产物的影响,以酯化度为考察目标,对合成时间、温度、催化剂用量、没食子酸和微晶纤维素用量比等因素进行考察,确定最佳合成条件为:没食子酸和微晶纤维素的反应物配比(GA∶MCC)为4∶1时,以磷钨酸为催化剂,催化剂用量为相对于没食子酸质量的10%,在温度120℃下,反应10 h,没食子酸微晶纤维素酯的酯化度最高。通过红外检测,合成产物红外谱图中1680 cm-1处有酯中C=O伸缩振动吸收峰,证明没食子酸与微晶纤维素不是机械混合而是化学合成。

Study on Synthesis of Microcrystalline Cellulose Gallate

Microcrystalline cellulose a renewable resource,was used the as raw material.A new type of ester gallate was synthesized from gallic acid containing antioxidant groups in the presence of catalyst.The effect of the three catalyets,toluene sulfonic acid,dodecylbenzene sulfonic acid and phosphotungstic acid,on the products was studied.The effect of synthesis time,temperature,catalyst amount,the ratio of gallate to microcrystalline cellulose and some other factors was also studied taking the esterfication degree as the criterion.The optimum synthesis conditions were as follows the ratio of GA to MCC was 4:1,the catalyst was phosphotungstic acid,the amount of catalyst was 10% of the gallate,the temperature was 120 ℃,and the time was 10h.Under these conditions the esterification degree of avicel gallate reached the maximum.There was a C=O stretching vibration absorption center at 1680 cm~(-1) on the infrared spectrum the synthesized product,indicating that the gallate acid and microcrystalline cellulose were not a mechanical mixtare but combined chemically.