机械活化玉米淀粉制备磷酸酯淀粉及其结构表征

利用自制的搅拌球磨机将普通玉米淀粉进行机械活化预处理,正磷酸盐为酯化剂,尿素为催化剂,干法制备淀粉磷酸酯.探讨了活化时间、磷酸盐用量、pH值、反应温度、反应时间和尿素用量对取代度(DS)和反应效率(RE)的影响,确定了最佳反应条件:活化时间1.5 h,磷酸盐用量12%,pH5.0,反应温度150℃,反应时间2 h,尿素用量3%,并对机械活化淀粉结构进行表征.研究结果表明:机械活化破坏了淀粉的结晶结构,有效地提高淀粉的化学反应活性,使合成的磷酸酯淀粉的DS和RE显著提高.

Synthesis of starch phosphate with mechanical activated maize starch

Maize starch was mechanically activated by a customized stirring-type ball mill and used to synthesize starch phosphate by dry process with orthophosphate as esterifying agent and urea as catalyst.The effects of activation time,reaction temperature and time,the amounts of urea and phosphates,the value of pH on degree of substitution(DS) and reaction efficiency(RE) were discussed and the best reaction conditions were determined as follows: activation time 1.5 h,amount of phosphate 12%,pH 5.0,the reaction tem...