摘要
采用正电子寿命谱(PLA)技术,通过探测聚酰胺固化环氧树脂(Epoxy)及环氧树脂/累托土(Epoxy/Rectorite)复合材料分别在不同温度点自由体积分布特性的变化,结果表明:在低温T=30K时,分子链段被冻结,自由体积分布变窄;温度在Tg及以上时,聚酰胺固化DGEBA环氧树脂中出现微相分离情况,观测到两种大小不同的自由体积孔洞的存在;纳米复合材料中累托土片层与高分子链段相互作用,同时片层促进了环氧树脂的交联,阻碍了复合材料的微相分离。
The distribution of free-volume-hole size in epoxy and epoxy/rectorite nanocomposites is studied as a function of temperature by positron annihilation. It observed that the distribution at low temperature is narrower than it at high temperature. The distribution becomes narrower because of the rectorite platelets separated in the nanocomposites. At the same time, at the Tg, the distribution of the free-volume-hole size has two peaks for the two materials. We consider it is caused by the firming agent-polyamide. The epoxy with different firming agent has been studied to improve our supposition. At the same time, the effect of rectorite platelets to distribution of free-volumehole size in epoxy and epoxy/rectorite naocomposites has been studied. It observed that the interaction between platelets and polymer matrix block the phase separation.
出处
《高分子通报》
CAS
CSCD
北大核心
2009年第12期75-79,共5页
Polymer Bulletin
基金
国家自然科学基金(50977093)资助项目
