PDVB-POSS协同膨胀阻燃低密度聚乙烯制备及性能研究

Study on synergistic effect of PDVB-POSSon intumescentflame retardant LDPE composites

为提高低密度聚乙烯(LDPE)的阻燃性能,以水热合成法制备的聚二乙烯苯多面体低聚倍半硅氧烷(PDVB-POSS)为阻燃协效剂,经熔融共混制备膨胀阻燃LDPE复合材料,采用多种方法研究了PDVB-POSS对LDPE复合材料阻燃性能以及力学性能等的影响。结果表明,当加入5.0%(质量分数)的PDVB-POSS时,极限氧指数(LOI)增加到32.4%,UL-94达到了V-0,同时拉伸强度达到17.7MPa,断裂伸长率增至596%。烟密度测试结果表明复合材料燃烧后烟气释放量降低,随着协效剂的增加,透光率增加。拉曼测试和扫描电镜证实燃烧后残炭石墨化程度和残炭量明显提高。研究表明PDVB-POSS可有效提高LDPE复合材料的阻燃性能和热稳定性,改善阻燃剂与基体材料之间的相容性。

To improve the flame retardant performance of low density polyethylene(LDPE),polydivinyl benzene-polyhedral oligomeric silsesquioxane composites(PDVB-POSS)synthesized by hydrothermal synthesis was used as flame retardant synergistic agent,and intumescent flame retardant LDPE composites were prepared by melt blending.The effects of PDVB-POSS on the flame retardancy and mechanical properties of LDPE composites were studied by various methods.The results showed that when 5.0 wt%PDVB-POSS was added,the limiting oxygen index(LOI)increased to 32.4%and the UL-94 reached V-0.Meanwhile tensile strength reached 17.7 MPa and the elongation at break was 596%.The smoke density test results showed that the smoke emission of the composite decreases after combustion,and the light transmittance increased with the increase of synergist.Raman test and scanning electron microscope confirmed that the graphitization degree and amount of residual carbon were significantly improved after combustion.The results showed that PDVB-POSS can effectively improve the flame retardancy and thermal stability of LDPE composites,and enhance the compatibility between flame retardant and matrix materials.