聚乳酸/聚己二酸-对苯二甲酸丁二醇酯共混物等温结晶行为及等温热处理对力学性能的影响  

Isothermal Crystallization Behavior of PLA / PBAT Blend and Effects of Isothermal Heating Treatment on Mechanical Performance of PLA / PBAT Blend

作　　者：王思思[1] 庞素娟[1] 徐鼐[1] 潘莉莎[1] 

机构地区：[1]海南大学材料与化工学院,海南海口570228

出　　处：《高分子材料科学与工程》2016年第8期38-44,共7页Polymer Materials Science & Engineering

基　　金：海南大学青年科学基金项目(qnjj1232);国家自然科学基金地区科学基金资助项目(51263007);海南省产学研一体化专项项目(cxy20150023)

摘　　要：通过熔融共混法制备聚乳酸(PLA)/聚己二酸-对苯二甲酸丁二醇酯(PBAT)(80/20)共混物,对其等温结晶行为、微观形貌、拉伸性能和维卡软化点(VST)进行研究。并在110℃时,利用等温热处理控制样品的结晶度,研究结晶度对样品拉伸韧性和VST的影响。结果发现,随着样品结晶度由9%增大至最大值36%,PLA基体中的无定形部分不断发生结晶,样品的断裂伸长率由256%骤降至11%,而VST值则由58℃提高至143℃。这是由PLA无定形部分与结晶部分巨大的性能差异所造成。当结晶度在27%时,其VST值达到123℃,断裂伸长率维持在160%左右,在增韧和耐热性能之间取得较好平衡。Poly （ lactic acid ） （PLA）/poly （ butylene adipate-co-terephthalate） （PBAT） （ 80/20 ） blends were prepared by melt-blending method. Isothermal crystallization behavior, microstructure, tensile properties and Vicar softening temperature （VST） of the PLA/PBAT blends were investigated systematically. PLA/PBAT samples with various crystallinity were obtained under isothermal heat treatment at 110 ℃. And influences of crystallinity on tensile toughness and VST of the samples were studied. As the crystallinity increases from 9 % to the maximum value of 36 %, the amorphous part of PLA matrix continuously transforms into crystal structure, and elongation at break of the samples drastically drops from 256% to 11%, while the VST value rises from 58 ＊（2 to 143 ＊C. It is attributed to huge nature difference between amorphous part and crystal part of PLA matrix. Notably, when the crystallinity of PLA matrix increases to 27 %, its VST value reaches 123 9C, and the elongation at break keeps around 160 %. In this situation, a better balance between toughness and heat deformation resistance is obtained in the PLA/PBAT blends.

关 键 词：聚乳酸 聚己二酸-对苯二甲酸丁二醇酯 结晶 拉伸性能 维卡软化点 

分 类 号：O631.13[理学—高分子化学]