不同结晶度聚烯烃对三元乙丙橡胶/氧化铝复合材料性能的影响  

Effect of polyolefin with different crystallinity on properties of ethylene-propylene-diene rubber/aluminum oxide composites

作　　者：苏珺[1] 李彩虹[1] 

机构地区：[1]南京工业职业技术学院机械工程学院,南京210023

出　　处：《合成橡胶工业》2013年第6期469-473,共5页China Synthetic Rubber Industry

基　　金：南京工业职业技术学院科研基金资助项目(QK12-01-03)

摘　　要：考察了4种不同结晶度的聚烯烃对三元乙丙橡胶(EPDM)/氧化铝复合材料的硫化特性、物理机械性能、导热性能和电性能的影响,并表征了硬脂酸改性氧化铝及其在复合材料中的微观相态。结果表明,氧化铝经硬脂酸表面改性后,硬脂酸分子包覆在氧化铝粒子的表面;当氧化铝为100份时,其在聚烯烃/EPDM复合材料中为球状,与聚丙烯、高密度聚乙烯(HDPE)、乙烯和烯烃共聚物的相容性较好,分散均匀,而与乙烯和乙酸乙烯酯共聚物(EVA)的界面结合较差;聚烯烃的加入使复合材料的最大转距和硫化速率降低,焦烧时间缩短;随着聚烯烃结晶度的增加,EPDM复合材料的撕裂强度增大,但HDPE/EPDM复合材料的邵尔A硬度最大;EVA/EPDM复合材料的拉伸强度和扯断伸长率最大,达到4.85 MPa和446%,但是撕裂强度较低,为17.74 kN/m;HDPE/EPDM复合材料的导热系数最大,达到0.549 W/(m·K),EVA/EPDM复合材料的导热系数为0.451 W/(m·K);聚烯烃的加入使复合材料的体积电阻率呈现降低的趋势,但表面电阻率变化不大,仍为同一数量级。The effects of four polyolefins with different crystallinity on cure characteristics,mechanical properties,thermal conductivity and electric properties of ethylene-propylene-diene rubber （EPDM） / aluminum oxide （Al2O3） composites were investigated.The micromorphology of aluminum oxide in composites were characterized.The results showed that the surface of A12O3 was coated with stearic acid after treatment,and that spherical Al2O3 particles were dispersed better and had more compatibility with polypropylene,high density polyethylene （HDPE）,ethylene olefin copolymer than ethylene-vinyl acetate （EVA）.The addition of crystallized polyolefin could decrease the maximum torque,cure rate and scorch time of EPDM composites.With increasing crystallinity of polyolefin,the tear strength of EPDM composites increased,and the Shore A hardness of the HDPE/EPDM composites was the highest.The tensile strength and elongation at break of the EVA/EPDM composites reached the maximum of 4.85 MPa,446％,respectively,but the tear strength was lower （17.74 kN/m）.The HDPE/EPDM composites had the highest thermal conductivity（0.549 W · m-1 · K-1）,while that of EVA/EPDM composites was 0.451 W · m-1 · K-1 The volume resistivity of EPDM composites had a decreasing trend with addition of polyolefin,but the surface resistivity of EPDM composites remained slightly changed.

关 键 词：三元乙丙橡胶 氧化铝 聚烯烃 结晶度 硫化特性 物理机械性能 导热系数 电性能 

分 类 号：TQ333.4[化学工程—橡胶工业]