制备方法对聚合物共混物相分离与黏弹弛豫的影响  

Effects of preparation method on liquid-liquid phase separation and viscoelastic relaxation of polymer blends

作　　者：上官勇刚[1] 吴远志[1] 陈锋[1] 姜贤[1] 周宇杰[1] 郑强[1] 

机构地区：[1]高分子合成与功能构造教育部重点实验室浙江大学高分子科学与工程系,杭州310027

出　　处：《中国科学：化学》2011年第2期391-397,共7页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(50603023);浙江省自然科学基金(Y4100314);中央高校基本科研业务费科研专项资助

摘　　要：采用小角激光光散射(SALLS)和动态流变方法研究了通过不同制备方法得到的等规聚丙烯/乙丙橡胶共混物(iPP/EPR)的相分离行为与黏弹行为.依据Cahn-Hilliard-Cook理论分析了熔融共混和溶液共混法制备的质量比为60/40和40/60的iPP/EPR共混物在恒温相分离早期的动力学,发现熔融共混iPP/EPR具有更大的表观扩散系数(Dapp).相分离中后期的实验结果表明,当相区尺寸增长程度相同时,熔融共混试样所用时间更短.表明熔融共混iPP/EPR试样具有更快的相分离速率.动态流变测试结果表明,与溶液共混相比,熔融共混试样具有更快的松弛速率.考虑到相分离过程实质是由高分子链的运动与扩散所控制,两种方法制备的iPP/EPR共混物相分离速率的差异应归于其分子链运动能力的不同.The liquid-liquid phase-separation（LLPS） and rheological behavior of isotactic polypropylene/ethylene-propylene rubber（iPP/EPR） blends prepared through different methods were studied through small angle laser light scattering（SALLS） and dynamic rheological measurement.The calculated apparent diffusion coefficient（Dapp） during early stage of LLPS and the time required by the same qmax shifting during late stage of LLPS were investigated.It is found that the phase separation rate of melt-blended iPP/EPR（m-iPP/EPR） is higher than that of the solution-blended samples（s-iPP/EPR）.Moreover,the results obtained through the dynamic rheological tests indicate that the relaxation rate of m-iPP/EPR sample is faster than that of s-iPP/EPR.It is suggested that the different phase separation rates between m-iPP/EPR and s-iPP/EPR are ascribed to the motion ability of polymer chain.

关 键 词：等规聚丙烯/乙丙 橡胶共混物 相分离 黏弹弛豫 制备方法 

分 类 号：O631.3[理学—高分子化学]