聚二甲基硅氧烷/碳酸钙复合体系流变性能研究

研究了聚二甲基硅氧烷(PDMS)/碳酸钙(CaCO3)复合体系的流变行为.用平板流变仪测得修饰后的碳酸钙复合体系的动态特性发现,随碳酸钙加入量的增加,复合体系的弹性随频率的增大而减小;低频下阻尼系数值明显降低,高频下阻尼系数值基本不变;阻尼系数随频率的增加,变化幅度减小;定频率下的储存模量和损耗模量都随温度的升高而下降.同时在对含量为20%修饰后的碳酸钙复合体系定频下振幅扫描后,没有发现Payne效应的存在.从而表明,修饰后的粒子之间的作用力不大.

Study on Rheological Properties of Polydimethylsiloxane Composites with Surface-modified CaCO3 Particles

The rheological properties of polydimethylsiloxane(PDMS)/CaCO3 system was investigated in this paper.The dynamic properties of PDMS/CaCO3 system containing modified CaCO3 were determined by plane-plate rheometer,and the results showed that the tendency that elasticity changed with frequency decreased when the content of the modified CaCO3 increased in PDMS/CaCO3.The damping coefficient had a bigger value in low frequency and almost a small constant in high frequency in PDMS/CaCO3 system.The changing range of damping coefficient decreased with the increase of frequency.With the same frequency,the storage modulus and loss modulus decreased with the increase of temperature.When the frequency was fixed,the results of amplitude sweeping of PDMS/CaCO3 system containing 20% modified CaCO3 showed that there was no Payne effect,namely,the interaction among particles was very little.