改性淀粉对炭黑填充丁苯橡胶/顺丁橡胶并用胶性能的影响

用改性淀粉替代部分炭黑填充丁苯橡胶(SBR)/顺丁橡胶(BR)并用胶,考察了改性淀粉用量及偶联剂种类对混炼胶硫化特性及硫化胶物理机械性能和动态力学性能的影响.结果表明,用改性淀粉替代部分炭黑可对SBR/BR混炼胶的硫化产生明显的延迟作用,但改性淀粉用量的变化对焦烧时间与正硫化时间影响不大;添加偶联剂KH-570或NDZ-201延迟了混炼胶的硫化过程,KH-550能大幅度地促进硫化作用,Si-69对于体系的硫化性能略有影响;随着改性淀粉用量的增加,SBR/BR硫化胶的拉伸性能、耐磨耗性均有所降低,但弹性、动态生热和滞后性能得到了明显改善,改性淀粉最佳用量为5～8份;各种偶联剂均可提高SBR/BR硫化胶的拉伸性能,硅烷偶联剂Si-69和KH-570对弹性和动态生热也略有改善,添加偶联剂KH-550改善了SBR/BR硫化胶的抗湿滑性能,但滞后性能变差,添加偶联剂KH-570或Si-69对SBR/BR硫化胶动态力学性能的影响较小,综合考虑,以添加偶联剂KH-570较好.

Effect of modified starch on properties of styrene-butadiene rubber/cis-1,4-polybutadiene rubber blend filled with carbon black

Styrene-butadiene rubber(SBR)/cis-1,4-polybutadiene rubber(BR) blends were filled with modified starch partly in stead of carbon black as reinforcement agent. The effects of amount of modified starch and type of couping agent on the cure characteristics of SBR/BR compounds, the mechanical properties and dynamic mechanical properties of vulcanizates were investigated. The results showed that the modified starch had a obvious delayed effect on the vulcanization of SBR/BR compounds, but the amount change of modified starch had little effect on scorch time and optimum cure time. Coupling agents KH-570 and NDZ-201 also had delayed effect on the vulcanization of SBR/BR compound, however, coupling agent KH-550 could significantly accelerate vulcanization, and coupling agent Si-69 had a little effect on the vulcanization. The tensile properties and abrasion property of SBR/BR vulcanizates decreased with increasing the amount of modified starch, but elasticity, heat building up and hysteresis effect improved, and the optimum amount of modified starch was 8 phr. Each of coupling agents could increase the tensile properties of vulcanizates, and coupling agent Si-69 or KH-570 could slightly improve the elasticity and heat building up of vulcanizates. Coupling agent KH-550 could improve the wet skid resistance of SBR/BR vulcanizates, but decreased the hysteresis effect. Coupling agent KH-570 or Si-69 had a little effect on dynamic mechanical properties of vulcanizates, in general the coupling agent KH-570 was suitable to the system.