The performances of hydrogenated nitrile rubber (HNBR) filled with carbon black N 330,N550,N 770,N990,zinc dimethacrylate(ZDMA) and N 770/ZDMA were studied, and the filler dispersion, morphological change and their relationships with the compression set were analyzed by using the rubber process analyzer and transmission electron microscope(TEM). The results showed that the mechanical properties of the rubber decreased, and the Payne effect of the polymer reduced with the increase of the particle size of carbon black, that was the better the carbon black dispersed, the smaller the compression set was. The rubber filled with carbon black had better thermal aging resistance and oil aging resistance. Among them, HNBR filled with carbon black N 770 had the best all-round properties. When 30 phr carbon black N 770 and suitable level ZDMA were filled into the HNBR, the tensile strength and elongation at break of HNBR vulcanizates increased significantly, and the compression setalso increased as the level of ZDMA increased, however, the Payne effect of vulcanizate had little change. TEM images indicated that the carbon black particles aggregated, and the distance between them got shortened after compressed for a long time under high temperature, but the particles themselves were not deformed. The compression set of HNBR vulcanizate filled with carbon black was basically due to the variations of molecular structures of the rubber, aggregation of carbon black particles and changes in their distribution. The dispersion of nano-fillers of poly-ZDMA in the HNBR was excellent. The polymer particles were easy to slip, deform and obviously aggregate, and their impediment to elasticity recovery of the macromolecular network was much higher than that of carbon black after compressed, so that the compression set was higher than that of carbon black filled HNBR.%研究了不同的炭黑(N 330,N 550,N 770,N 990)、甲基丙烯酸锌及炭黑N 770与甲基丙烯酸锌并用填充氢化丁腈橡胶(HNBR)的性能,用橡胶加工分析仪和透射电镜分析了填料的分散性、形态变化及其与胶料压缩永久变形的关系.结果表明,随炭黑粒径增大,胶料的力学性能有所降低,Payne效应减小(即炭黑的分散性变好),压缩永久变形减小.炭黑填充胶料具有较好的耐热老化和耐油性能,相比较而言,炭黑N 770填充胶料的综合性能最好.在填充30份(质量)炭黑N 770的HNBR中并用适量的甲基丙烯酸锌,随其用量增加胶料的强度和扯断伸长率明显增大,压缩永久变形增大,Payne效应变化不大.透射电镜分析结果表明,高温下长时间压缩后,炭黑粒子间的距离缩短,粒子有聚集现象,但粒子本身未发生变形.这表明炭黑填充胶料的压缩永久变形主要源于橡胶分子结构的变化、炭黑粒子的聚集及分布状态的变化.聚甲基丙烯酸锌在HNBR中的纳米分散性优异.由于压缩后该离聚体粒子易产生滑移、变形和明显的聚集现象,对大分子网络弹性恢复的阻碍作用远高于炭黑,因而胶料的压缩永久变形比炭黑填充者要大得多.
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