退火对聚乳酸/淀粉复合材料性能的影响  

Effect of Annealing on the Properties of Poly(Lactic Acid)(PLA)/Starch Composite

作　　者：李永辉 彭显达 戴文利[1] LI Yonghui;PENG Xianda;DAI Wenli(Institute of Polymer Science and Engineering,Xiangtan University,Xiangtan,Hunan 411105,China)

机构地区：[1]湘潭大学,化学学院高分子材料研究所,湖南湘潭411105

出　　处：《塑料》2018年第6期98-101,共4页Plastics

摘　　要：以改性木质素(MZS)作为成核剂,通过双螺杆挤出机制备了聚乳酸(PLA)/乙烯-醋酸乙烯酯(EVA)/淀粉/MZS复合材料。采用差示扫描量热仪(DSC),偏光显微镜(POM),热变形、维卡软化点温度测定仪分析了成核剂和退火处理对PLA/EVA/淀粉复合材料结晶性能及耐热性能的影响。结果表明,MZS是PLA/EVA/淀粉复合体系的一种有效成核剂,在添加1.5%MZS后,复合材料的结晶速率加快、结晶度变大;在未添加成核剂时,PLA/EVA/淀粉复合材料的结晶度为3%,在添加1.5%MZS后,复合材料的结晶度达到47.9%;退火处理可以改善复合材料的耐热性;在105℃退火5 min时,PLA/EVA/淀粉复合体系的维卡软化点和热变形温度分别达到60.4、55.0℃;PLA/EVA/淀粉/MZS复合体系的维卡软化点和热变形温度分别达到80.8、82.8℃。Modified ligin was added into poly (lactic acid)(PLA)/ethylene vinylacetate (EVA)/starch composite as a nucleating agent which was prepared by melt blending using a twin screw extruder.The crystallization and thermal behaviors of the composite were studied by differential scanning calorimetry (DSC),polarized optical microscope (POM),vieat softening point tester,heat deflection tester,respectively.It showed that the MZS was an effective nucleating agent of the PLA/EVA/ Starch composite.The addition of the 1.5%MZS increased the crystallization rate of the composite and the degree of erystallinity.Without addition of nucleating agent,the erystallinity of the composite was 3%.When the weight content of MZS was 1.5%,the degree of crystallinity reaehed to the maxium,it was 47.9%.Annealing treatment could improve the crystallization and the heat resistance of the composite.Compared to PLA/EVA/Stareh eomposite,with the addition of MZS, the vicat softening temperature and heat distortion temperature increased from 60.4、55.0℃ to 80.8、82.8℃ while it was annealed at 105℃ for 5min.

关 键 词：聚乳酸 改性木质素 退火 结晶性能 耐热性能 

分 类 号：TQ325.2[化学工程—合成树脂塑料工业]