纳米SiO_2填充聚二甲基硅氧烷的微观结构在热贮存中的演变动力学  

Microstructure evolution kinetics of polydimethylsiloxane filled with nano-SiO_2 composites during thermal annealing

作　　者：林桂[1] 吴友平[1] 钱燕超[1] 张立群[1] 

机构地区：[1]北京化工大学北京市新型高分子材料制备与成型加工重点实验室

出　　处：《合成橡胶工业》2006年第6期439-444,共6页China Synthetic Rubber Industry

基　　金：国家自然科学基金资助项目(50303002);教育部博士点基金资助项目(20020010004);北京市自然科学基金重点资助项目(2031001)。

摘　　要：分析了纳米SiO2填充聚二甲基硅氧烷(PDMS)复合体系在热贮存停放过程中微观结构的变化及其对动态性能的影响,提出了表征填料在橡胶基体中分散特征的方法,研究了填料聚集动力学及其机理。结果表明,纳米SiO2填充PDMS复合体系在低应变低频率下的动态储能模量(E′0)可以用来表征纳米无机粉体在橡胶基体中的分散特征,其测试条件为应变不大于0·70%,频率1Hz;复合体系的E′0随着贮存停放时间的延长逐渐增大;当PDMS/SiO2(质量比)为100/100时,E′0恢复动力学的活化能约为3·01kJ/mol;随着贮存停放时间的延长,复合体系中的纳米SiO2聚集更为稠密,结合胶含量增加并逐渐达到平衡;改性纳米SiO2填充PDMS复合体系的E′0在热贮存停放初期有小幅度的增大趋势,之后基本保持恒定。The microstructure evolution of polydimethylsiloxane （PDMS） filled with nano-SiO2 composites during thermal annealing and influence on the dynamic properties were analyzed. The dispersivity of filler in the rubber matrix was characterized. The kinetic process and mechanism of aggregation of filler were studied. The results showed that the dynamic storage modulus （E0′） at small strain amplitude （ ≤ 0.70% ） and low frequency （1 Hz） could be used to evaluate the dispersion characteristics of PDMS filled with nano-SiO2 composites. E0′ increased with increasing thermal annealing time and the activation energy was calculated as 3.01 kJ/mol for PDMS/SiO2 （mass ratio 100/100）. The agglomeration of nano-silica aggregated, bound rubber content increased and reached equilibrium with increasing thermal annealing time. E0′ of PDMS filled with modified nano-SiO2 increased slightly at the beginning of the thermal annealing and almost kept constant after that.

关 键 词：纳米二氧化硅 聚二甲基硅氧烷 热贮存停放 微观结构 动态储能模量 

分 类 号：TQ330.1[化学工程—橡胶工业]