不同聚乳酸对聚乳酸/淀粉共混复合膜的影响

Effects of Different PLAs on the PLA/TPS Composite Films

目的探究不同聚乳酸基材对聚乳酸/热塑性淀粉共混复合膜基础性能的影响,筛选最适合的聚乳酸基材。方法选取REVODE 101,REVODE 110,REVODE 711B等3种聚乳酸原材料作为基材,与热塑性淀粉共混,采用热压法制备复合膜,并对复合膜进行动态热力学性能、力学性能、透湿性、水溶性及水分含量的表征。结果以REVODE110为基材制备的复合膜玻璃化转变温度(tg)最高,在增塑剂乙酰柠檬酸三丁酯质量分数为20%时tg为36.16℃,室温下稳定性最佳;其力学性能、透湿性以及水溶性与REVODE101复合膜相近,且显著优于REVODE 711B复合膜,3种复合膜透光性无显著差异,透光率T600均在14%左右。结论 3种聚乳酸材料中,REVODE 110是最适宜制备聚乳酸/淀粉复合膜的聚乳酸基材。

The work aims to explore the effect of different polylactic acid substrates on the basic performance of polylactic acid/thermoplastic starch blended composite films, and screen the polylactic acid substrates which are suitable as the raw materials. Three kinds of polylactic acid(REVODE 101, REVODE 110 and REVODE 711 B) were selected as the substrates and blended with the thermoplastic starch to prepare the composite films through hot pressing. The dynamic thermomechanical properties, mechanical properties, moisture permeability, water solubility and water content of the composite films were characterized. The results showed that the composite film prepared with REVODE 110 had the highest glass transition temperature(tg) compared with the others, and the tg was 36.16 ℃ when the mass fraction of plasticizer acetyl tributyl citrate(ATBC) was 20%. Then, it had the best stability at room temperature. What’s more, its mechanical properties, moisture permeability and water solubility were similar to those of REVODE 101, but much better than those of REVODE 711 B. The transmittance of these three composite films was similar, which was all around 14%(T600). REVODE 110 is the most suitable polylactic acid substrate for polylactic acid/starch composite films.