PCL在PCL/PLLA复合材料中的结晶行为研究

Study on crystallization behavior of PCL in PCL/PLLA composite

研究了PCL(聚己内酯)在PCL/PLLA(聚左旋乳酸)共混物或共聚物中的结晶行为,结果表明:PCL与PLLA为不相容体系,共混物在80℃热熔结晶后仅出现轻微相分离,但在180℃熔融后则出现明显的相分层;共聚物由于存在化学键作用,相分离现象不明显,但PCL结晶受限比共混物更严重。基于PCL与PLLA不相容的特性,通过2种不同的方法分别制备了PCL/PLLA双层膜和叠加膜,研究发现:在双层膜中由于两膜界面处存在部分混溶,导致PCL膜形成规整的环带球晶;叠加膜由于不存在界面混溶,只能形成普通黑十字消光球晶。

The crystallization behavior of PCL(polycaprolactone) in PCL/PLLA[poly(L-lactic acid)]blend or copolymer was investigated.The results show that the PCL/PLLA is incompatible system,and only slight phase separation occurred in the blend after hot-melt crystallizing at 80℃,but obvious phase delamination occurred after melting at 180℃;the phase separation phenomenon is not obvious in the copolymer because of the existence of chemical bonding action,but the crystallization of PCL is more severely restricted than that in the blend.Based on the incompatibility of PCL and PLLA,the PCL/PLLA double layer film and stacked film were respectively prepared by two different methods.It is found by study that,in the double layer film,the PCL film forms the regular banded spherulite due to partial miscibility at the interface of the two films;in the stacked film,only ordinary black cross extinction spherulite is formed due to the absence of interfacial miscibility.