高填充量耐油乙烯-醋酸乙烯酯共聚物电缆材料的制备及性能

Preparation and Properties of Highly Filled Ethylene-Vinyl Acetate Copolymer Cable Materials with Oil-Resistant Performance

应用聚硅氧烷低聚物(FPSO)对二氧化硅(SiO_2)、氢氧化铝(ATH)和氢氧化镁(MH)的混合物进行改性,并将改性后的无机混合物与乙烯-醋酸乙烯酯共聚物(EVA)进行熔融共混复合,制备出无机物填充量达50%的EVA电缆材料。采用扫描电镜(SEM)、差示扫描量热仪(DSC)、旋转流变仪、万能试验机和极限氧指数测试仪对EVA电缆材料的结构和性能进行表征与测试。SEM结果显示,FPSO的引入促进了高含量无机混合物在EVA基体中的分散,材料燃烧后的炭渣表面结构完整;DSC测试结果表明,FPSO含量较低时,EVA的结晶能力提高,有利于电缆材料力学性能的改善。流变测试结果揭示,FPSO的引入在削弱填料间相互作用的同时提高了无机粒子与基体间的界面黏结力,有利于提高材料的耐油及阻燃性能;当FPSO的质量分数为0.48%时,电缆材料具有较好的力学、耐油及阻燃性能。

A kind of functional polysiloxane oligomer(FPSO)was employed to mix with silicon dioxide(SiO2),aluminium hydroxide(ATH)and magnesium hydroxide(MH)for modifying the inorganic particles,and then the modified inorganic compound(MIC)was introduced into ethylene-vinyl acetate copolymer(EVA)via melt blending,then the EVA cable materials containing 50%MIC modified with different dosages of FPSO were prepared.The structure and properties of the materials were studied by SEM,DSC,rotational rheometer,electronic universal testing machine,etc.SEM images show that the presence of FPSO promotes the dispersion and compatibility of MIC in EVA matrix and a compact and stable residual char is formed from the combustion of EVA cable materials.DSC curves show that the crystallinity of EVA is enhanced since the lower dosages of FPSO is introduced into EVA composites,hence mechanical properties of which are improved.The rheological testing reveals there is an obvious reduction of storage modulus and loss modulus due to the existence of FPSO,as a consequence of the better dispersion of MIC in EVA matrix and the strong interfacial adhesion between MIC and EVA.With only 0.48%FPSO loading,the EVA composites exhibit better mechanical,low smoke,halogen-free flame retardant and oil resistant performance,which would show promising prospects in harsh environment when used as cable materials.