CM/XNBR共混物老化性能研究

Study on the Aging Properties of CM/XNBR Blends

采用过氧化物硫化体系研究了不同老化时间对氯化聚乙烯橡胶(CM)/羧基丁腈橡胶(XNBR)共混硫化胶交联密度及力学性能、耐油性能等的影响规律。结果表明,随热空气老化时间的增加,XNBR相交联密度先增加后降低,CM相交联密度呈上升趋势,两相交联密度之差先增加后降低;松弛时间先降低后略有上升,体系整体交联密度先增加后略有下降;拉伸强度和100%定伸应力逐渐上升后略有降低,撕裂强度基本呈上升趋势,拉断伸长率先下降后趋于稳定,硬度上升后趋于稳定,永久变形和体积磨耗量先降低后增加。随热油老化时间增加,拉伸强度和拉断伸长率先降低后趋于平稳,100%定伸应力先上升后趋于平稳,体积和质量变化率均明显上升。

The effects of different ageing time of XNBR and CM on the crosslinking density, the mechanical properties and oil-resistance properties of CM/XNBR vulcanizate cured with peroxides system were studied. The results showed that with the increase of ageing time. the crosslinking density of XNBR increased and then decreased, the crosslinking density of CM increased, the difference between XNBR and CM increased and then decreased; relaxation time decreased and then increased, the crosslinking density of blends increased and then decreased; the tensile strength and modulus at 100% increased and then decreased, the tear strength increased, the elongation at break decreased, the hardness increased, the tension set and the volume abrasion quantity decreased and then increased; with the increase of hot oil ageing time, the tensile strength and the elongation at break decreased, modulus at 100% increased, the volume and mass change ratio increased.