聚(3-羟基丁酸酯-3-羟基己酸酯)/聚乳酸共混物的增容研究

摘要

以聚氧化乙烯(PEO)、苯乙烯-甲基丙烯酸缩水甘油酯共聚物(REC)、乙烯-甲基丙烯酸甘油酯共聚物(E-GMA)、乙烯-丙烯酸酯-甲基丙烯酸甘油酯共聚物(E-MA-GMA)、马来酸酐接枝聚乳酸(PLA-g-MAH)为增容剂,通过熔融共混法制备了聚(3-羟基丁酸酯-3-羟基己酸酯)/聚乳酸[PHBH/PLA=80/20(质量比,下同)]共混物,采用差示扫描量热仪、动态力学分析仪、扫描电子显微镜及电子万能试验机等研究了PHBH/PLA的热性能、表面形貌及力学性能,并依此判断共混物的相容性以及各相容剂对共混昆物相容性的影响.结果表明,PHBH和PLA呈部分相容;相容剂REC或PLA-g-MAH对PHBH/PLA具有相对较好的增容效果,共混物中PHBH与PLA两相的玻璃化转变温度(Tg)差值减小,共混物中分散相粒径尺寸减小且分布均匀,当添加4％的REC和PLA-g-MAH后,共混物的冲击强度分别提升了43.8％和53.6％,断裂伸长率分别提升了100％和120％.%Poly(3-hydroxybutyrate-3-hydroxyhexanoate)/poly(lactic acid) (PHBH/PLA=80/20) blends were prepared via a melt blending method by using poly(ethylene oxide) (PEO),styreneglycidyl methacrylate copolymer (REC),ethylene-co-glycidyl methacrylate (E-GMA),ethylenemethyl acrylate-glycidyl methacrylate terpolymer (E-MA-GMA) and maleic-anhydride-grafted poly (lactic acid) (PLA-g-MAH) as compatiblizers.Mechanical properties,morphology and thermal properties of the blends were characterized by differential scanning calorimetry,dynamic thermomechanical analyzer,scanning electron microscopy and universal testing machine.The compatibility of PHBH/PLA was evaluated,and the effect of the compatibilizers on their compatibility was investigated.The results indicated that the effect of the compatibility was better with addition of REC or PLA-g-MAH,and the presence of REC or PLA-g-MAH reduced the difference between the glass-transition temperatures of PHBH and PLA and also reduced the particle size of dispersed phase with a more uniform distribution in the blends.Moreover,at a content of 4 wt ％ of REC or PLA-g-MAH,the impact strength increased by 43.8 ％ and 53.6 ％,and the elongation at break increased by 100 ％ and 120 ％,respectively.