撕裂模式下乙烯-丙烯酸甲酯共聚物/氯丁橡胶热塑性硫化胶的Mullins效应及其可逆回复

Mullins effect and its reversible recovery of ethylene-methyl acrylate copolymer/chloroprene rubber thermoplastic vulcanizate under tearing mode

采用动态硫化法制备出乙烯-丙烯酸甲酯共聚物(EMA)/氯丁橡胶(CR)热塑性硫化胶(TPV),考察了不同m(EMA)/m(CR)时TPV的撕裂强度,研究了撕裂模式下TPV的Mullins效应及其热处理下的可逆回复行为。结果表明,当m(EMA)/m(CR)为40/60时EMA/CR TPV的撕裂强度最高;在单轴循环撕裂模式下EMA/CR TPV存在明显的Mullins效应,当应变速率增大时EMA/CR TPV的最大撕裂强度、内耗和阻尼因子均呈增大趋势;当撕裂应变增大时EMA/CR TPV的最大撕裂强度、瞬时残余形变、内耗和阻尼因子均呈增大趋势,但应力软化因子呈减小趋势。热处理后EMA/CR TPV的Mullins效应的可逆回复能力增强,并且在80℃时的可逆回复效果达到最佳。

Ethylene-methyl acrylate copolymer(EMA)/chloroprene rubber(CR)thermoplastic vulcanizate(TPV)was prepared by dynamic vulcanization and tear strength with different m(EMA)/m(CR)was investigated.The Mullins effect of TPV under tear mode and reversible behavior under heat treatment were studied.The results showed that tear strength of EMA/CR TPV was the highest when m(EMA)/m(CR)was 40/60.There was obvious Mullins effect in EMA/CR TPV under uniaxial cyclic tearing mode,and when the strain rate increased,the maximum tear strength,internal friction and damping factor of EMA/CR TPV all increased.When the tear strain increased,the maximum tear strength,instantaneous residual deformation,internal friction and damping factor of EMA/CR TPV all increased,but the stress softening factor decreased.The reversible recovery ability of Mullins effect of EMA/CR TPV was enhanced after heat treatment,and the reversible recovery effect was the best at 80℃.