摘要
以硅烷接枝改性低密度聚乙烯(s-LDPE)对甲基乙烯基硅橡胶/二氧化硅(MVQ/SiO2)混炼胶补强,尿素为物理发泡剂,采用溶析成孔法制备了开孔MVQ/s-LDPE/SiO2泡沫材料,系统研究了MVQ/s-LDPE共混比和尿素发泡剂用量对泡沫材料性能的影响,通过扫描电子显微镜(SEM)对泡沫材料孔结构进行了观察。结果表明:随s-LDPE用量增加,MVQ/s-LDPE/SiO2泡沫材料的邵氏A硬度、拉伸强度和撕裂强度增加,抗压缩变形能力增强,补强作用明显;随发泡剂用量增大,泡沫材料泡孔分布更加均匀,孔隙率增加,力学强度和抗压缩变形能力逐渐降低。
Open cellular MVQ /s-LDPE /SiO2foams are prepared through a solventing-out foaming method using silane grafted low density polyethylene( s-LDPE) as a reinforcement agent and urea as a physical foaming agent. The effects of MVQ /s-LDPE mass ratios and urea amounts on the mechanical properties,compression stress relaxation and porosity of the foams are investigated. The open cell structure of pore is observed by scanning electron microscopy photographs. The result shows that the hardness,tensile strength,tear strength and compressibility modulus of MVQ /SiO2foams increase while the compression stress relaxation decreases with increasing the amount of s-LDPE. As a result of the increase in urea amounts,the mechanical properties are weakened but the compression stress relaxation is improved. The distribution of foams became evenly and the porosity elevated. Compared with MVQ /SiO2foams,most of the mechanical properties of MVQ /s-LDPE / SiO2foams are improved.
引文
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