丁腈橡胶在液压油中的加速老化行为

摘要

The high-temperature accelerated aging tests in hydraulic oil with temperatures of 110 ℃, 130 ℃ and 150 ℃ were carried out on a nitrile-butadiene rubber.Then the effects of aging time on the tensile property and hardness of the rubber were studied and the aging behavior was analyzed.The service life of the rubber was also predicted by using Arrhenius equation.The results show that during the aging process, under the combined effects of oil swelling, crosslinking and chain broking, the tensile strength of the nitrile-butadiene rubber first kept unchanged then decreased, the hardness first decreased then increased and the maximum percentage elongation decreased exponentially.According to the maximum percentage elongation data, the service life predicted by Arrhenius equation of the nitrile-butadiene rubber in 25 ℃ hydraulic oil was 2 836 d, which was equivalent to the real life.The prediction result was relatively accurate.%通过对丁腈橡胶在110,130,150 ℃液压油中进行高温加速老化,研究了老化时间对该橡胶拉伸性能和硬度的影响,分析了其加速老化行为,并利用阿伦尼乌斯方程预测了其使用寿命.结果表明:在老化过程中,在吸油溶胀、交联和断链的综合作用下,丁腈橡胶的抗拉强度先保持不变然后降低,硬度先减小后增大,扯断伸长率呈指数下降趋势;根据扯断伸长率数据,使用阿伦尼乌斯方程预测得到丁腈橡胶在25 ℃液压油中的使用寿命为2 836 d,与实际寿命相当,预测较准确.