摘要：在橡胶加工体系中, 采用偶联剂双-[γ- (三乙氧基硅) 丙基]四硫化物 (Si69) 与硫磺 (S) 进行互配, 保持橡胶内部硫含量不变, 制备白炭黑 (SiO2) -天然橡胶 (NR) 复合材料;借助无转子流变仪、万能拉伸试验机、橡胶加工分析仪等对白炭黑-天然橡胶复合材料进行表征, 考察不同Si69-S互配对橡胶复合材料的硫化特性及力学性能的影响。结果表明:随着Si69逐渐替代S含量, 白炭黑-天然橡胶复合材料的硫化特性得到改善, 白炭黑在天然橡胶基体中的团聚程度减弱, 分散性逐渐提高;硫化温度越高, 反应速率常数越大;随着Si69逐渐减少, S量逐渐增多, 断裂伸长率与撕裂强度总体呈增大趋势;当Si69质量为4.2 g、S的质量为1 g时, 硫化胶的拉伸强度达到最大值, 为33.8 MPa。
关键词：白炭黑；天然橡胶；硫化温度；力学性能
Abstract：In rubber processing system, according to employing the way of making bis[3- (triethoxysilyl) propyl]tetrasulfide (Si69) and the sulfur be reciprocal properly to keep the internal sulphur content of rubber into contant, further to prepare the composite material of Si O2-NR. The Si O2-NR composite material were characterized by universal tensile testing machine, rotorless rheometer and rubber process analyzer. The effects of different Si69-S ratio on curing property and mechanical properties of Si O2-NR composites were studied. The results show that the curing properties of the composites are improved with the S contents being replaced gradually by Si69, and the degree of agglomeration of silica increased in the rubber matrix, which leads the dispersion to become worse. The higher the curing temperature, the larger the reaction rate constant. With the decrease of Si69 and the increase of S, the elongation at break and tear strength overall trend to increase. When Si69 is 4.2 g, S is 1g, the tensile strength of vulcanized rubber reach the maximum, which is 33.8 MPa.
Keywords: precipitated silica；nature rubber；vulcanization temperature；mechanical property
