环烷油对PP/EPDM动态硫化热塑性弹性体的影响

运用动态硫化法制备聚丙烯(PP)/三元乙丙橡胶(EPDM)动态硫化热塑性弹性体(TPV),研究了EPDM含量对TPV性能的影响,发现PP/EPDM质量比为60/40时,TPV的拉伸性能达到最大,在此优化配比下研究了环烷油充油前后TPV拉伸性能、结晶性能、热稳定性能、动态力学性能及流变性能的变化规律。结果表明,环烷油的加入使得PP/EPDM拉伸强度下降,断裂伸长率增加;环烷油阻碍TPV中PP相的结晶,其结晶、熔融温度及相应焓值在充油过后都有所下降;环烷油降低了TPV的热降解速率,且使TPV中EPDM相和PP相分子链的玻璃化转变温度(T_g)降低,其中EPDM相的T_g降低更明显,同时熔融状态下TPV的复数黏度、储能模量和损耗模量下降,表明熔融状态TPV中聚合物分子链运动能力增加,分子链内摩擦减小,加工性能得到提高。

Effects of Naphthenic Oil on PP/EPDM Dynamic Vulcanized Thermoplastic Elastomer

Polypropylene(PP)/ethylene propylene diene monomer rubber(EPDM)dynamic vulcanized thermoplastic elastomer(TPV)was prepared by dynamic vulcanization method,the effects of EPDM content on the properties of TPV were studied,it is found that when the mass ratio of PP/EPDM is 60/40,the tensile properties of TPV reach maximum.Under the optimized proportioning,the changes of tensile and crystallization properties,thermal stability,dynamic mechanics and rheological behaviors of the TPV filled or unfilled with naphthenic oil were studied.The results show that,addition of naphthenic oil makes the tensile strength of the TPV decrease but elongation at break increase.Naphthenic oil can inhibit the crystallization of PP in the TPV,which leads to declines of the values of crystalline and melting temperature including corresponding enthalpy of the TPV.Naphthenic oil decrease the thermal degradation rate of the TPV and the glass transition temperature(Tg)of EPDM or PP molecular chains in the TPV,the Tg of the EPDM decreases more greatly.The value of complex viscosity,storage and loss modulus of the TPV decrease in the molten state after filling the oil,which means,the movement ability of polymer molecular chain of the TPV under the molten state increases,the internal friction of the molecular chain decreases along with the rigidity decreases,the processing performance is improved.