聚丙烯β晶对动态硫化EPDM/PP性能的影响

Effect of PolypropyleneβCrystal on the Properties of Dynamic Vulcanized EPDM/PP

采用熔融共混法制得不同含量的β成核剂改性三元乙丙橡胶(EPDM)/聚丙烯(PP)动态硫化热塑性弹性体(β⁃TPV)样品。并通过电子万能试验机、差示扫描量热仪、广角X射线衍射仪等,分析了体系中的β晶含量对材料的力学性能及熔融结晶性能的影响。结果表明,成核剂可以成功诱导TPV中聚丙烯β晶的生成,且随着成核剂含量的增加,TPV中β晶的含量逐渐增加,而在体系中,PP相的总结晶度基本不变。因此,添加成核剂,可以使材料的拉伸性能有所提升,当成核剂含量为0.4%时,与纯TPV相比,拉伸强度提高了11.4%,断裂伸长率提高了29.0%;除此以外,与纯TPV相比,β成核剂能够提高材料的结晶温度,最高可以达到10℃。

Ethylene propylene diene monomer rubber(EPDM)/polypropylene(PP)dynamically vulcanized thermoplastic elastomer(EPDM/PP⁃TPV)with differentβnucleating agent(β⁃NA)content was prepared by melt blending.The effects ofβ⁃NA content on mechanical properties,melting and crystallization properties of materials were analyzed by universal mechanical test,differential scanning calorimeter and wide angle X⁃ray diffraction respectively.The result implied thatβ⁃NA could successfully induce beta crystal formed,and the increasing dosage of theβ⁃NA content,the content ofβphase also increased while the total crystallinity remained steady at the blend.Moreover,the tensile strength of TPVs was slightly improved by the addition ofβ⁃NA.When the addition ofβ⁃NA was 0.4%,tensile strength could be enhanced by 11.4%,elongation at break could be improved by 29.0%.We also found that the temperature of TPV could be enhanced by nucleating agent,which could be improved 10℃compared with pure TPV.