【摘要】 制备了甲基丙烯酸缩水甘油醚(GMA)接枝乙烯-醋酸乙烯共聚物(GEVA)和马来酸酐(MA)功能化改性淀粉(MST),并利用红外光谱(FT-IR)和核磁共振谱(NMR)对二者的结构进行了表征。采用熔融共混法制备了聚乳酸(PLA)/MST/GEVA复合材料,其中固定MST和GEVA的质量分数均为20%。通过拉伸、冲击、扫描电镜(SEM)、差示扫描量热(DSC)等测试方法对复合材料的性能进行了研究。结果表明:GEVA的加入使复合材料的韧性得到明显改善,断裂伸长率最高可达170%,冲击强度提高了400%左右;随着GEVA接枝率的提高,淀粉逐渐被GEVA相包覆,促进了淀粉在PLA基体中的分散;同时复合材料的吸水性降低,结晶能力减弱。更多还原

【Abstract】 Glycidyl methacrylate grafted poly(ethylene)-co-(vinyl acetate)(GEVA)and maleated thermoplastic starch(MST)were prepared,and their structures were characterized by Fourier transform infrared spectroscopy(FT-IR)and nuclear magnetic resonance(NMR).Composites of poly(lactic acid)(PLA) /MST/GEVA were prepared by melt blending.The mass fraction of MST and GEVA in the composites was fixed at 20%.The properties of the PLA/MST/GEVA composites were investigated by tensile strength,impact strength,scanning electron microscope(SEM)and differential scanning calorimeter(DSC).The results showed that the addition of GEVA remarkably improved the toughness of the composites,the elongation at break of the composites could reach 170% and the impact strength increased by about four times;With the increase of graft ratio of GEVA,starch granules were gradually coated by GEVA,and the dispersion of starch granules in PLA matrix were improved.In addition,the water absorption of the composites decreased,and the crystallization of the composites reduced.更多还原