纳米碳酸钙/IFR对聚丙烯发泡材料的协效阻燃

Synergistic Flame Resistant Effect of Nano-CaCO_3/IFR on Polypropylene Foams

通过氧指数(LOI)、力学性能、泡孔结构及热重分析(TG),探究了纳米碳酸钙/IFR复合阻燃体系对PP发泡材料性能的影响和机理。结果表明:Nano-Ca CO_3与IFR存在协效作用,能有效改善PP复合泡沫材料的阻燃性能,使氧指数显著提升;Nano-Ca CO_3的添加能提升阻燃PP发泡材料的力学性能,并且添加量存在最优值。另外通过扫描电镜发现:Nano-Ca CO_3的添加可以提高IFR与PP的相容性,使阻燃PP复合发泡材料的泡孔结构更规整,泡孔孔径减小,孔密度增大。TG结果表明:Nano-Ca CO_3能提高阻燃PP复合发泡材料的热稳定性,形成更致密的炭层,提升了热失重率。随着Nano-Ca CO_3添加量的增大,PP/IFR/Nano-Ca CO_3复合发泡材料的氧指数、力学性能和热稳定性都呈现先增大后减小的趋势,因此当PP/IFR/Nano-Ca CO_3质量比为80:20:2时,复合发泡材料综合性能较优。

Based on the characterization of limiting oxygen index （LOI） , mechanical properties test, cell structure and thermogravimetric analysis （TG） , the effect mechanism of Nano-CaCO3/ intumescent flame retardant （IFR） flame retardant system on properties of polypropylene （PP） foams was investigated. The results showed that, there existed the synergy effect between Nano-CaCO3 and IFR, which could effectively improve the flame retardant properties of PP foams, so that LOI increased greatly. The addition of Nano-CaCO3 could improve the mechanical properties of flame retardant PP composite foams and the additive amount had an optimal value. The SEM picture of cell morphology of PP foams showed that, Nano-CaCO3 could improve the compatibility between IFR and PP, which made the cell structure more regular and uniform, the cell size of PP composite foams decreased and the cell density increased. TG results showed that Nano-CaCO3 could improve the thermal stability of PP composite foams, forming more compact carbon layer and rising the residual weight. Generally, with the increasing content of Nano-CaCO3, LOI and mechanical properties as well as thermal stability of PP/IFR/Nano-CaCO3 composite foams all showed first increased and then decreased trend, so 80： 20：2 weight ratio of PP/IFR/Nano-CaCO3 was the optimum for these performances.