摘要
采用偏光显微镜和透射电镜研究了 PS-b-PEO-b-PS三嵌段共聚物的结晶形态和微相分离 ,重点讨论了 PEO含量和分子量的影响。实验发现 ,当共聚物中的 PEO分子量低至 60 0 0、含量低至 4 2 %时 ,均有球晶生成 ,且随着 PEO含量的升高 ,球晶形态变得更加完善。 TEM结果显示 ,当 PEO分子量为1 0 0 0 0、含量分别为 93%和 91 %时 ,形成以 PEO为连续相、PS为分散相的微相分离结构 ;但当 PEO含量降低到 77%时 ,发生了相反转 ,PEO变为分散相 ,PS变为连续相。当 PEO分子量为 60 0 0 ,含量为 4 2 %时 ,形成了以 PS为连续相、PEO为分散相的微相分离结构。所有的分散相都有球形或近似球形的形貌。在 PEO的分子量为 2 0 0 0、含量为 1 8%、34 %时 ,发现了层状微相分离结构。同时我们还发现 ,p H=6.
The effects of PEO contents and molecular weight on the micro-phase separation bejaviors amd crystalline morphologies of PS-B-PEO-B-PS triblock copolymers were investigated by Optical Microscopy and TEM technologies.It was observed by the Optical Microscopy that spherulitic crystallization growth was realized ,when the PEO molecular weight were no less than 6000 and the PEO contents were higher than 42%,furthermore,That the the spherulitic textures became more and more cleaner as the PEO contents increased.In the case of that PEO molecular weight was 10000 and the PEO contents were 91% and 93%,the micro-phase separation sturctures with PEO as continuous phase and PS as dispersed phase was formed.But,when PEO contents decreased form 91% to77%,PEO became into dispersed phase and PS became into contimuous phase,moreover,this kind of micro-phase separation structure was also observed in the case of that PEO molecular weight was 6000 and PEO content was 42%.The experimental results showed that all dispersed phase were spherulitic or pseudo spherulitic shape..Lamellae micro-phase separation structures were observed when PEO molecular weight was 2000 and the contents were 18% or34%.The PEO crystallization and the interlay between crystalization and micro-phase separation of the triblock copolymers probably led to the difference of the micro-phase exparation behavior between the glassy block copolymers and the crystalline block copolymers.
出处
《胶体与聚合物》
2001年第3期8-12,共5页
Chinese Journal of Colloid & Polymer
