交联键类型对硫化丁苯橡胶拉伸应力松弛行为的影响

Tensile stress relaxation of unfilled SBR rubbers with different crosslink natures

利用两相模型讨论了不同硫化体系的硫化丁苯橡胶的应力松弛行为。通过平衡溶胀法求得不同硫化体系中存在的几种不同交联网络结构的含量。普通硫化体系(CV)含有较多的多硫交联键,有效硫化体系(EV)含有较多的单硫交联键,而半有效硫化体系(SEV)的单硫、多硫交联键含量在前两者之间。考察了交联键类型、拉伸速率以及应变对应力松弛行为的影响。结果表明,CV体系的拉伸强度、不可松弛分量都要高于其它2种体系。交联键类型对可松弛分量的影响较小。

In this work, the two-component model was used to investigate the stress relaxation behavior of different vulcanization systems of unfilled styrene butadiene rubber. The content of different crosslink network natures in different vulcanization systems were obtained through the swelling method. Conventional vulcanization system （CV） contains polysulphide crosslink nature, and efficient vul- canization （EV） system contains monosulphide crosslink nature, while the content of polysulphide crosslink nature and monosulphide crosslink nature of semi-efficient vulcanization （SEV） system was between the former two systems. The influence of the crosslink natures, stretching rate and the strain on the stress relaxation behavior was studied. The results suggested that the tensile strength and the non-relaxation stress component of CV system were higher than that of the other two systems. In ad- dition,the crosslink natures have less effect on the relaxation stress component.