含聚己内酯的聚乳酸基立构复合物的制备与性能

Preparation of Poly(lactic acid) Stereocomplex Containing PCL and Physical Property

将聚(右旋丙交酯-ε-己内酯)二元共聚物(PDLCA)以及聚(左旋丙交酯-ε-己内酯)二元共聚物(PLLCA)分别与聚左旋乳酸(PLLA)进行溶液共混,对PLLA进行改性,并进行对比。探讨了共聚物的添加量以及共聚物中LA/CL(LA/CL为共聚物中丙交酯与ε-己内酯的投料摩尔比)的共聚摩尔比对立构复合物的形成以及PLLA力学性能的影响。研究表明,聚己内酯(PCL)柔性链段对PLLA具有增韧效果,经过对比发现,PDLCA中的PDLA链段与PLLA之间形成的立构复合物对材料的拉伸强度具有一定的保持作用,当LA/CL为90/10,PDLCA添加量为50%时,效果最佳,材料的断裂伸长率达到30%,比PLLA的韧性提高了328%,同时,拉伸强度没有明显降低。

Poly( D-lactide)-co-poly( ε-Cl)( PDLCA)/PLLA and poly( L-lactide)-co-poly( ε-Cl)( PLLCA)/PLLA blends were prepared by solution blend method. The physical modifications on PLLA were studied. Influence of the PLCA(PLLCA and PDLCA) blending ratio and LA/CL copolymerization ratio( LA/CL was the molar ratio of LA and ε-Cl in copolymer) on the formation of PLA stereocomplex as well as the mechanical properties were studied. The results showed that the PCL had a toughening effect on PLLA. By contrast,the formation of stereocomplex between PDLA segment and PLLA had a positive effect on PLLA. Finally,when LA/CL was 90/10,the blending ratio of PDLCA was 50%,the sterecomplex-PLA was best. The elongation at break was 30%,which was 328% higher than PLLA. At the same time,the tensile strength was well maintained.