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

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 ℃.