环氧化天然橡胶对天然橡胶/白炭黑湿法母炼胶性能的影响

将乳胶状的环氧化天然橡胶(ENR)作为界面改性剂应用于NR/白炭黑的湿法混炼,通过对比ENR改性处理的湿法母炼胶(NES)和未经改性处理的湿法母炼胶(NS),研究ENR对湿法母炼胶性能的影响。结果表明:胶料中的填料-填料网络主要是在硫化初期填料絮凝而形成,通过热处理能够降低NES的填料絮凝速率。与NS相比,不管有没有偶联剂存在,NES均具有更低的絮凝速率常数和由此导致的更弱的填料-填料网络;随着偶联剂用量的增加,胶料的300%定伸应力和耐磨性提高,且NES的提高幅度更大。分析认为,ENR一方面在白炭黑表面形成聚合物层,防止填料的絮凝;另一方面能够与硅烷偶联剂起协同作用改善填料-橡胶界面结合。

Effect of Epoxidized Natural Rubber on the Properties of Natural Rubber / Silica Wet Masterbatch

Epoxidized natural rubber (ENR)was used as the interfacial agent for the wet compounding of NR/ silica, and the effect of ENR on the properties of the materbatches was studied through the comparison of the wet masterbatch with ENR modification(NES)and the wet masterbatch without modification(NS). Results showed that the filler-filler netnetwork was formed mainly at the beginning of the vulcanization, NES had a lower filler flocculation rate and the resulting filler-filler netnetwork was weaker comparing with NS with or without coupling agents. The modulus at 300% and wear resistance of the composites were improved as increasing the loading of coupling agents, and the improvements for NES were more obvious. It suggests that the role of ENR is forming a polymer layer on the silica surface and preventing filler flocculation, and having a synergistic effect with silane coupling agents leading to a stronger filler-rubber interfacial bonding.