白炭黑填充NR拉伸疲劳过程中介观结构及动态粘弹性的演变

Evolution of Mesoscopic Structure and Dynamic Visco-elasticity of NR filled with Silica during Tensile Fatigue Process

通过改变白炭黑粒子的网络化程度,系统地研究了其填充天然橡胶在拉伸疲劳过程中的介观结构及动态粘弹性能。结果表明,硫化胶疲劳寿命与白炭黑粒子的网络化程度呈线性关系;疲劳试验后,硫化胶Payne效应的下降幅度与白炭黑粒子的网络化程度正相关;疲劳前试样的损耗因子tanδ达到峰值时所需应变高于疲劳后试样;tanδ随疲劳程度的增大而升高,疲劳前试样的E′值对温度的依赖性较强,填充50份白炭黑的NR橡胶E′下降过程可分为2个阶段;白炭黑粒子在疲劳过程中出现一定程度的团聚现象。

The evolution of mesoscopic structure and dynamic visco-elasticity of SBR filled with silica during the tensile fatigue process was investigated systematically by changing silica network degree.The results showed that there was a linear relationship between fatigue life of SBR vulcanizate and silica network degree.The decrease amplitude of Payne effect of the fatigued vulcanizates was positively correlated with silica network degree,and the needed strain as tanδof unfatigued sample achieved the peak value was higher than that of fatigued sample.The tanδincreased with increase of fatigue degree,and the temperature-dependence of the storage modulus of unfatigued sample was high.There were two decrease steps for the storage modulus of NR filled with 50 phr silica.The silica aggregates turned to be agglomeration to some degree during the fatigue process.