丁基橡胶/聚丙烯热塑性硫化胶的结晶和动态力学性能研究

Crystallization and Dynamic Mechanical Properties of IIR/PP TPV

采用动态硫化法制备丁基橡胶(IIR)/聚丙烯(PP)热塑性硫化胶(TPV),研究橡塑比对TPV结晶性能、动态力学性能和物理性能的影响,并与IIR/PP简单共混胶进行对比。结果表明:与简单共混胶和PP相比,TPV的结晶温度和熔点较低,随着橡塑比的增大,TPV的结晶温度降低,结晶度减小,结晶时间延长;随着橡塑比的增大,TPV的储能模量总体降低,且TPV中IIR相的玻璃化转变温度向高温方向移动,PP相的损耗峰减弱,两相相容性增强;在-60^-30℃范围内,与相同橡塑比TPV相比,简单共混胶的储能模量较低,IIR和PP两相相分离明显;与简单共混胶相比,TPV的硬度、拉伸强度和拉断伸长率较大,溶胀比较小;随着橡塑比的增大,TPV的硬度和拉伸强度减小,溶胀比和拉断伸长率呈增大趋势。

Butyl rubber(IIR)/polypropylene(PP)thermoplastic vulcanizate(TPV)was prepared by dynamic vulcanization,the effects of rubber-plastic ratio on the crystallinity,dynamic mechanical properties and physical properties of TPV were investigated,and its properties were compared with those of IIR/PP blends.The results showed that,the crystallization temperature and melting point of TPV were lower than those of simple blends and PP,respectively.With the increase of rubber-plastic ratio,the crystallization temperature and crystallinity of TPV were lowered,crystallization time was prolonged,the storage modulus of TPV decreased,the glass transition temperature of the IIR phase in TPV moved toward a high temperature direction,the loss peak of the PP phase was weakened,and the compatibility of the two phases was enhanced.Compared with the TPV with same rubber-plastic ratio,in the temperature range of-60 to-30℃,the storage modulus of the simple blends was lower,and the phase separation between IIR phase and PP phase was obvious.Compared with the simple blends,the hardness,tensile strength and elongation at break of TPV were larger,and swelling ratio was smaller.With the increase of rubber-plastic ratio,the hardness and tensile strength of TPV decreased,and the swelling ratio and elongation at break increased.