LDPE/SEBS复合材料化学交联及相关性能的研究

Study on Chemical Cross-Linking and Related Properties of LDPE/SEBS Composites

采用二段混炼的方法,制备低密度聚乙烯/苯乙烯-乙烯-丁烯-苯乙烯嵌段共聚物(LDPE/SEBS)复合材料。探究SEBS的不同含量对LDPE/SEBS力学性能的影响。通过双叔丁基过氧异丙基苯(BIBP)化学交联LDPE/SEBS,制备LDPE/SEBS/BIBP复合材料,探究LDPE/SEBS/BIBP的力学性能、微观形貌、凝胶含量、热学性能和流变性能。结果表明:SEBS用量为50份时,LDPE/SEBS具有较好的力学性能。当BIBP用量为0.9份,LDPE/SEBS/BIBP的力学性能最佳,拉伸强度为26.22 MPa,断裂伸长率为732.23%。随着BIBP用量的增加,LDPE/SEBS/BIBP的界面相容性、凝胶含量和黏度上升,熔融温度、结晶度和损耗模量下降,储能模量曲线的斜率先下降后趋于稳定。

Low density polyethylene/styrene-ethylene-butene-styrene block copolymer(LDPE/SEBS) composites were prepared by two-stage mixing method. The effects of different SEBS contents on the mechanical properties of LDPE/SEBS were investigated. LDPE/SEBS/BIBP composites were prepared by chemical crosslinking of bis(1-(tertbutylperoxy)-1-methylethyl)-benzene(BIBP) with LDPE/SEBS. The mechanical properties, microstructure, gel content,thermal properties and rheological properties of LDPE/SEBS/BIBP were investigated. The results show that LDPE/SEBS has better mechanical properties when SEBS content is 50 phr. When the BIBP content is 0.9 phr, the mechanical properties of LDPE/SEBS/BIBP is the best, with tensile strength of 26.22 MPa and elongation at break of 732.23%. With the increasing of BIBP content, the interfacial compatibility, gel content and viscosity of LDPE/SEBS/BIBP is increased,the melting temperature, crystallinity and loss modulus is decreased, and the slope of storage modulus curve first is decreased and then tended to be stable.