writer：Linyao Zhou, Guiyan Zhao, Yulin Feng, Jinghua Yin, Wei Jiang
keywords：聚乳酸, 抗冲击, 淀粉醋酸酯, 酯化度, 生物降解聚合物共混物
source：期刊
specific source：Carbohydrate Polymers, 2015, 127, 79-85
Issue time：2015年

摘要：将天然玉米淀粉用乙酸酐酯化并以甘油增塑，得到热塑性淀粉醋酸酯（TPSA），再与聚乳酸（PLA）和甲基丙烯酸缩水甘油酯接枝聚醚嵌段酰胺（PEBA-g-GMA）共混，制备了兼具高缺口冲击强度和低成本的可生物降解PLA/PEBA-g-GMA/TPSA共混物。与PLA/PEBA-g-GMA共混物相比，少量乙酰化的热塑性淀粉可替代多达9 wt%的昂贵PEBA-g-GMA弹性体，同时保持高冲击强度。力学性能取决于淀粉醋酸酯的酯化度：随着酯化度从0增加到0.04，冲击强度、拉伸强度和断裂伸长率均升高至峰值，进一步增加酯化度则性能下降。形貌结果表明，在最佳酯化度0.04时，TPSA粒子更小且更均匀，从而使力学性能达到峰值。

Abstract：Native corn starch was esterified with acetic anhydride and plasticized with glycerol to give thermoplastic starch acetate (TPSA). TPSA was blended with polylactide (PLA) and polyether-block-amide-graft-glycidyl methacrylate (PEBA-g-GMA) to obtain biodegradable PLA/PEBA-g-GMA/TPSA blends with high notched impact resistance and low cost. Compared with PLA/PEBA-g-GMA blends, as much as 9 wt% expensive PEBA-g-GMA elastomer could be substituted by the slightly acetylated thermoplastic starch while retaining high impact strength. The mechanical properties depended on the esterification degree of starch acetate. The impact strength, tensile strength and elongation at break increased to the peak value with increasing the esterification degree from 0 to 0.04, thereafter they decreased on further increasing the esterification degree. The morphological results showed that the TPSA particles were smaller and more uniform at the optimum esterification degree of 0.04, leading to the peak value of the mechanical properties.

论文链接：https://doi.org/10.1016/j.carbpol.2015.03.022