聚己内酯和聚氧化乙烯共混体系中的两类片晶相间堆砌

ALTERNATIVE STACKING OF TWO KINDS OF LAMELLAR SYSTEMS FROM POLY (ε-CAPROLACTONE) AND POLY (ETHYLENE OXIDE) IN THEIR BLENDS

对聚(ε-己内酯)(PCL)/聚氧化乙烯(PEO)共混物的相差显微镜、广角X-射线衍射(WAXD)、小角X-射线散射(SAXS)及示差扫描量热计(DSC)等的研究表明,只有当共混物中PCL(或PEO)的含量低于20％时,两组份是相容的.当PCL含量低于20％时,在共混物中形成了PEO片晶和PCL片晶相间堆砌的结晶形态,当PEO含量不超过20％时,PEO则完全以非晶形式混入PCL的非晶区,同时阻碍了PCL的结晶.可见在结晶过程中,相容的两组份对共混体系形态结构的影响却不尽相同.

The compatibility of poly (ε-caprolactone) (PCL) and poly (ethylene oxide) (PEO) as well as the crystallization behavior and morphology of their blends have been studied. These two polymers with their melting temperature close to each other can be compatible within a given range of composition.In blends with minor PCL, it was found from small angle X-ray scattering experiment that not only a scattering peak from PCL lamellar stacks but also another peak located at an scattering angle lower than that from PCL lamellar stacks were observed. This peak should be corresponding to the scattering by a kind of sandwitch lamellar ones from alternative stacking of PCL and PEO lamellar systems. In addition, in blend with minor PEO, it is shown that PEO could not crystallize during the crystallization of PCL.