ESBR硫化胶交联结构及动态粘弹性在拉伸疲劳过程中的变化

研究炭黑和白炭黑填充乳聚丁苯橡胶硫化胶拉伸疲劳过程中交联结构和动态粘弹性的变化。结果表明,炭黑填充胶料的拉伸性能在拉伸疲劳次数低于50万次时下降明显,而白炭黑填充胶料在50万～100万次之间下降幅度较大;随着拉伸疲劳次数的增加,两种胶料的交联密度均减小;拉伸疲劳次数达到200万次时,炭黑填充胶料的tanδ峰宽明显增大,而白炭黑填充胶料在拉伸疲劳次数50万次以上tanδ峰就明显增高、增宽;炭黑填充胶料疲劳后高弹态的tanδ变化不大,而白炭黑填充胶料tanδ显著增大;白炭黑填充胶料的Payne效应较炭黑填充胶料大,且拉伸疲劳后Payne效应明显减小。

Changes in crosslink structure and dynamic viscoelasticity of ESBR vulcanizate during tensile fatigue

The changes in crosslink structure and dynamic viscoelasticity during the process of tensile fatigue of ESBR vulcanizate filled with carbon black and silica were investigated. The results showed that, the tensile properties of carbon black filled compound decreased obviously while the number of fatigue testing cycle got to 500 000, but for silica filled compound, the cycle number was up to 500 000-1 000 000;the crosslink densities of the two compound were both decreased as the cycle number increased;the peak width of tanδ with carbon black filled compound increased significantly when cycle number reached 2 000 000,whereas the peak of tang risen and widen obviously when cycle number got to 500 000 for silica filled compound; the tanδ of carbon black filled compound in the rubber elastic region changed little, but the tang of silica filled compound increased greatly; the Payne effect of silica filled compound was more significant than that of carbon black filled compound,and the former＇s Payne effect decreased obviously after tensile fatigue.