SA/PVA可降解复合塑料膜的制备与性能研究

Preparation and Property of SA/PVA Biodegradable Plastics Film

对木薯原淀粉进行乙酰化改性,合成低酯化度的木薯淀粉醋酸酯(SA);经增塑、交联后与聚乙烯醇(PVA)合成可降解的SA/PVA复合塑料膜,重点研究了PVA、甘油、乙二醛的用量及SA的酯化度对复合膜力学性能的影响,并对复合膜性能进行了表征。结果表明:在PVA质量分数为40%,甘油质量分数为14%,乙二醛质量分数为4%时,可以得到力学性能较好的复合塑料膜;与原淀粉/PVA复合膜相比,复合膜致密性提高,玻璃化转变温度降低,结晶度下降,表现出更好的力学性能。

Cassava starch acetates （SA） with different degree of esterification were synthesized from cassava starch by reacting with acetic acid/acetic anhydride, which was then plasticized and crosslinked to reacted with PVA to synthesize SA/PVA biodegradable plastics film. The effects of the contents of PVA, glycerin and glyoxal, and the degree of esterification on the mechanical properties of the film were discussed. The results showed when the con- tents of PVA, glycerin and glyoxal were 40%, 10%, and 4% respectively, the film with the best mechanical properties could be prepared. Compared with those of native starch/PVA films, the compactness of SA/PVA film was better, and the glass transition temperature and crystallinity of SA/PVA film decreased, resulted in better mechanical properties.