硫化体系对天然橡胶性能的影响

Effect on vulcanization system on properties of natural rubber

采用常规硫化体系(CV)、半有效硫化体系(SEV)和有效硫化体系(EV)制备了不同的NR(天然橡胶)硫化胶。着重探讨了不同硫化胶的微观形貌、200%定伸强度、撕裂强度、拉伸强度、断裂伸长率和交联密度。研究结果表明:SEV硫化胶的微观形貌相对较好,填料能均匀分散在基体中;在其他条件保持不变的前提下,当w(NOBS)=w(硫)=2.0%(相对于NR质量而言)时,相应的未老化SEV硫化胶的撕裂强度(78 kN/m)相对最大;SEV硫化胶的交联密度大于CV硫化胶和EV硫化胶,并且适当增加交联密度能有效提高其综合性能,从而为开发新一代轮胎等复合材料奠定了基础。

The different NR （natural rubber） vulcanizates were prepared by conventional vulcanization （CV）, semi-effective vulcanization （SEV） or efficient vulcanization （EV）. The mierotopography, 200% stretching strength, tear strength, tensile strength, elongation at break and crosslinking density of different vulcanizates were emphatically discussed. The research results showed that the microstructures of vulcanizates were relatively better because the fillers could be evenly dispersed in matrix. The corresponding un-aging SEV vulcanizate had the relatively maximum tear strength （78 kN/m） when other conditions were unchanged, and the mass fractions of NOBS or S were all 2.0% in NR. The crosslinking density of SEV vulcanizate was larger than that of CV vulcanizate or EV vulcanizate, and the appropriately increasing crosslinking density could effectively improve the combination property of SEV vulcanizate, so the basis for developing new generation of tire composites was established.