天甲胶乳对天然橡胶/白炭黑复合材料的增容作用研究

天甲胶乳(MG)是甲基丙烯酸甲酯与天然胶乳的接枝共聚产物,主要用于粘合表面性质不同的材料。在湿法混炼工艺的基础上,以天甲胶乳作为增容剂对天然橡胶/白炭黑复合材料进行增容。研究了MG对复合材料中白炭黑分散性、硫化特性、Payne效应、物理机械性能、动态力学性能的影响。结果表明,采用MG增容天然橡胶/白炭黑复合材料时,白炭黑含量为10 phr时平均粒径最小,分散等级最高,分别为7.6μm和9.9。NR/SiO_2-MG的正硫化时间有所下降,白炭黑为40 phr时T₉₀缩短最明显,从17.2 min降低到13.9 min。在白炭黑含量10 phr时,NR/SiO_2-MG的Payne效应明显降低,白炭黑在NR基体中分散性能提高,胶料加工性能改善。加入增容剂的NR/SiO_2-MG的拉伸强度和撕裂强度都比未添加增容剂样品好。NR/SiO_2-MG的抗湿滑性在白炭黑为20 phr时明显提高,同时NR/SiO_2-MG的滚动阻力明显降低。

Study on the compatibilization effect of grevertex on natural rubber/silica composites

Grevertex(MG)is a graft copolymerization product of methyl methacrylate and natural rubber latex,which is mainly used to bond materials with different surface properties.Natural rubber/silica composites were prepared by wet-compounding technology with grevertex as a compatibilizer.The effects of MG on the dispersion of silica,vulcanization characteristics,payne effect,mechanical properties,and dynamic mechanical properties were investigated.The results showed that the average particle size was the smallest and the dispersion grade was the highest which was 7.6μm and 9.9 respectively when the content of silica was10 phr and MG was used for compatibilization.the T 90 of NR/SiO2-MG decreased slightly.T 90 shortened most obviously when the content of silica was 40 phr from17.21 to13.87 min.The Payne effect of NR/SiO2-MG decreased obviously when the content of silica was10 phr.The dispersibility of silica in NR matrix was improved and the processability of rubber was improved.The tensile strength and tear strength of NR/SiO2-MG were better than that of NR/SiO2.the wet grip resistance of NR/SiO2-MG is higher than that of NR/SiO2 when the content of silica was 20 phr,and the rolling resistance of NR/SiO2-MG is lower than that without compatibilizers.