原位增强PLA/PBS合金的微观形态及力学性能研究

Morphology and Mechanical Properties of PLA/PBS Alloy via In-situ Reinforcement

以聚乳酸(PLA)和聚丁二酸丁二醇酯(PBS)为原料,过氧化二异丙苯(DCP)为增容剂,通过具有"扁平口模"的双螺杆挤出机进行熔融混合,利用热拉-骤冷成型工艺制备了一系列PLA/PBS合金。分别采用扫描电子显微镜(SEM)、广角X-射线衍射(WAXD)、差示扫描量热仪(DSC)和万能试验机测试研究了原位增强PLA/PBS合金的断面形态、结晶性能和力学性能。结果表明,PLA在PBS基体中形成了微纤增强形态,PLA微纤的形成未改变PBS基相的晶型;PLA微纤的形成使PLA/PBS合金的拉伸强度、弯曲强度与冲击强度分别较纯PBS提高了7.4%、28.9%和6.1%。随着DCP的加入,PLA微纤尺度降低且与PBS基体界面结合更紧密;当DCP的添加量为0.5%时,PLA/PBS合金的力学性能最佳。

With poly （ lactic acid） （PLA） and poly （ butylenes succinate ） （ PBS ） as raw materials and dicumyl peroxide （DCP） as the compatibilizer, a series of PLA/PBS alloys were prepared by melt compounding via twin-screw extruder with flat die and through heat-drawing with quenching process. Scanning electron microscope （ SEM ）, wide angle X-ray diffraction （ WAXD ）, （DSC） and universal testing machine were used to study the interface differential scanning calorimetry morphology, crystallization and mechanical performance of the PBS based alloys, respectively. Results show that the PLA in-situ microfibers distribute in PBS matrix, and they do not change the crystal form of PBS phase ; compared to pure PBS, the tensile and flexural and impact strength of PLA/PBS alloys with in-situ microfibers increase by nearly 7.4%, 28.9% and 6. 1%, respectively. Additionally, with the addition of DCP, the sizes of PLA in-situ microfibers reduce and the interfacial bonding of PLA and PBS is tighter; when the DCP content is 0. 5 wt%, the mechanical properties of PLA/PBS alloys are the optimal.