聚左旋乳酸/聚丁二酸丁二醇酯共混物的结构与性能

Preparation and Characterization of Poly( L-Lactic Acid) / Poly( Butylene Succinate) Blends

通过熔融共混制备出一系列不同组成比的聚左旋乳酸(PLLA)/聚丁二酸丁二醇酯(PBS)/醋酸锌(Zn(OAc)2)样品,通过扫描电子显微镜、动态力学性能分析仪、差示扫描量热仪及力学性能测试等,研究了不同PBS及Zn(OAc)2含量对PLLA/PBS共混物的形态结构、结晶性能和力学性能的影响。结果表明,PLLA和PBS属于非相容体系,Zn(OAc)2的加入能降低PBS相区的尺寸,提高PLLA/PBS体系的相容性,且质量分数为0.05%时增容效果最佳;PBS的加入可有效提高PLLA的结晶速率和结晶度;随着PBS含量的增加,共混物的断裂伸长率和冲击韧性与纯PLLA相比显著提高,共混物的断裂伸长率均在300%以上;当PLLA/PBS/Zn(OAc)2质量比为80/20/0.05时,共混物的综合性能最优。

Poly（L-lactide） （PLLA）/poly（butylene succinate） （PBS）/zinc acetate （Zn（OAc）2） blends with different compositions were prepared by melt blending. The morphology, crystallization behavior and mechanical properties of PLLA/PBS/Zn（OAc）2 blends were investigated by SEM, DMA, DSC and mechanical tests. The results show that PLLA/PBS blends are incompatible and exhibit phase-separated morphology. Addition of Zn（OAc）2 leads to a decrease of PBS domain size, thereby improving the compatibility between PLLA and PBS. The smallest domain size is found in PLLA/PBS blends containing 0.05% Zn（OAc）2. The addition of PBS can effectively improves the crystallization rate and crystaUinity of PLLA. Moreover, the impact strength and the fracture elongation of PLLA/PBS blends increase with increasing PBS content compared with pure PLLA. The elongation at break of PLLA containing PBS is above 300%. The blend with m （PLLA）/m （PBS）/rn （Zn（OAc）2） = 80/20/0.05 shows the best mechanical properties.