尿素缓释膜材料高取代醋酸酯淀粉的研制

采用醋酸酐作为酯化剂,吡啶作为活化催化剂,液相均相催化反应技术制备尿素缓释膜材料高取代度(DS)醋酸酯淀粉。分别考察制备过程中单一影响因素对醋酸酯淀粉取代度的影响关系,并结合正交实验得出影响因素结论与最佳反应条件。醋酸酐用量是影响醋酸酯淀粉取代度的主要因素,吡啶用量、活化时间和反应时间对取代度的影响为次要因素。最佳反应条件:可溶性淀粉20g,吡啶用量30mL,活化时间1h,醋酸酐用量60mL,反应时间1h,在此条件下制得的醋酸酯淀粉的取代度DS=2.94。

Preparation of high substituent acetic starch ester-film material for carbamide controlled release

Using acetic anhydride as esterifying agent, pyridine as activation catalyst .Applying liquid homogeneous catalyzing reaction skill for preparation of carbamide controlled release film material high substituent (DS)acetic starch ester. Seeing about respectively influence of single reaction parameter on substituting degree of acetic starch and finally we adopted orthogonal test optimization method to obtain the result of influence of substituting degree and the best reaction condition. Amount of acetic anhydride is main factor, amount of pyridine , activation time and reaction time are secondary factors and the best reaction condition are as follows: soluble starch is 20 g ,pyridine is 30 mL, activation time is 1 h, acetic anhydride is 60 mL, reaction time is 1 h.Under this condition we will obtain high substituent acetic starch ester(DS=2.94).