PBAT/PLA复合材料的制备及其微球发泡行为研究

Study on Preparation of PBAT/PLA Composites and Its Microsphere Foaming Behavior

采用熔融共混法制备了聚（己二酸丁二醇酯-对苯二甲酸丁二醇酯）/聚乳酸（PBAT/PLA）共混复合材料,并对PBAT/PLA共混体系的流变性能、结晶性能、力学性能、微观形貌以及发泡行为（热膨胀微球作为发泡剂）进行了表征。结果表明：随着PLA含量的增加,PBAT/PLA共混体系的非牛顿指数先减小后增大,其中当PLA含量为30%时达到最小值;PLA的引入改善了PBAT的结晶性能,且PBAT与PLA对彼此的晶型均无影响;随PLA含量的增加,PBAT/PLA共混体系的拉伸强度增大、断裂伸长率降低,其中当PLA含量为50%时,拉伸强度和断裂伸长率分别达到25.3 MPa和422.2%;PLA与PBAT的相容性差,当PLA含量为30%时,PLA/PBAT共混体系发生相分离;此外,当PLA含量为10%时,PBAT/PLA复合发泡材料的密度达到最小值0.34 g/cm^3。

Poly（butylene adipate terephthalate）/polylactic acid（PBAT/PLA） composites were prepared by melt blending method. The rheological properties, crystallinity, mechanical properties, microstructure and foaming behavior of PBAT/PLA blends or PBAT/PLA foaming system（with the thermal expansion microspheres as foaming agent） with different PLA contents were characterized. The results show that the non-Newtonian index of the PBAT/PLA composites decreases first and then increases with the increasing PLA content, and achieves the minimum when the PLA content is 30%. The crystallization performance of PBAT can be improved by adding PLA, and PBAT or PLA has no effect on the crystal shape of each other. With the increase of PLA content, the tensile strength of PBAT/PLA blends increases, and the elongation at break decreases. When the PLA content is 50%, the tensile strength and the elongation at break respectively achieves 25.3 MPa and 422.2%. PBAT and PLA are partially compatible, and when the PLA content is 30%, the two phases separate. When the PLA content is 10%, the density of the PBAT/PLA composite foam material reaches the minimum 0.34 g/cm-3.