再生聚乙烯回掺量对无卤阻燃保温泡沫材料性能的影响

Effectsof regeneration polyolefin addition on properties of halogen-free and flame resistance foam heat insulating materials

将再生聚乙烯(RPE)与低密度聚乙烯(LDPE)共混改性,采用红磷和无卤阻燃PE母粒,利用二段发泡工艺进行发泡,制备无卤阻燃保温材料。研究了RPE回掺量对材料力学性能、阻燃性能、保温性能的影响,并进行了燃烧烟气成分分析。结果表明,掺入RPE,不仅可以降低成本,而且可以改善纯LDPE凝胶率低的问题,更容易采用二段发泡法,各项性能均有所改善。当RPE回掺量为50%时性能指标达到最佳:发泡倍率为32(体积倍率),氧指数为30,垂直燃烧速度13mm/min,吸水率为0.0016g/cm3,导热系数为0.017W/(m.K)。材料燃烧后,烟气主要成分为聚乙烯热裂解产物,表明聚乙烯泡沫材料在燃烧过程中与氧气的接触不好,未检测到二噁英等有毒气体。

A new kind of flame-resistance heat-insulating foam was synthesized by blending the low density polyethylene （LDPE） with the regeneration polyolefin（RPE）by employing the two-steps foaming method, in which the red phosphorus, halogen-free and flame resistant PE masterbatches were used as the flame retardant agents. The optimum blending ratio and physicochemical properties, such as the mechanical performance, flame retardancy, heat insulation performance, as well as the combustion smoke composition were also investigated. The results indicated that, in addition to reducing the cost, blending RPE could improve the low gel rate of pure LDPE, which would make it much easier to go through second pressured foaming of polyolefin foam and also the improved the capacities of the foam. In addition, the optimum blending ratio of LDPE and RPE was 50%, when performance of the material got the best： the foaming ratio was 32, the oxygen index reached 30, the vertical burning velocity was 13mm/min, the water absorbed rate was 0. 0016g/cm3 , the thermal conductivity was 0. 017W/（m . K）. After combustion, the constituents of the smoke was similar with that of the pyrolysis products of polyethylene, which indicated the PE foam material had a poor contact with oxygen in the combustion process and the dioxin and others toxic gases were also not been detected.