纳米SiO_2对动态硫化EPDM/PP热塑性硫化胶性能的影响

Effect of nano-SiO_2 on the properties of EPDM/PP thermoplastic vulcanizate

采用不同硫化体系动态硫化制备三元乙丙橡胶/聚丙烯热塑性硫化胶(EPDM/PP TPVs),并在制备的过程添加不同量的纳米SiO2。结果表明酚醛树脂2402动态硫化得到的EPDM/PP TPVs性能最佳。随着纳米SiO2添加量的增加,EPDM橡胶粒子的粒径先减小后增大,当纳米SiO2的添加量为10份时,EPDM橡胶粒子的粒径达到最小。流变性能研究表明添加纳米SiO2使EPDM/PP TPVs的加工性能变差。动态机械分析仪(DMA)研究表明纳米SiO2提高了TPVs中PP相的玻璃化转变温度。当纳米SiO2的添加量为10份,TPVs的拉伸强度达到最高为23.7MPa,提高了19.1%,断裂伸长率达到最大为431%,提高了11.1%。纳米SiO2使EPDM/PP TPVs的热稳定性和耐热老化性能变好。

This article reports the preparation,characterization,and properties of the thermoplastic vulcanizate（TPV）/nano-SiO2 nanocomposites.We can produce EPDM/PP TPVs with high performance using octylphenol-formaldehyde resin and stannous chloride dehydrate as vulcanizing agents.Morphology study showed that the dimension of EPDM particles decreased with the increase of nano-SiO2 and the minimum dimension of EPDM particles was reached when 10 phr nano-SiO2 was filled.RPA study revealed that the processability of the TPVs become poor by adding nano-SiO2.Thermogravimetric study and heat-aging study indicated that thermal stability and heat-aging property could be improved in presence of nano-SiO2.Dynamic mechanical analysis showed that the glass-transition temperature of the PP phase of the nanocomposite increased as compared to virgin TPVs.With the increase of nano-SiO2 concentrations,significant improvement in tensile strength,and elongation at break of TPVs has been achieved.