硫氧镁水泥/聚苯乙烯复合材料燃烧性能研究

针对聚苯乙烯易燃、易产生有毒气体的问题,以硫氧镁水泥、聚苯乙烯颗粒制作硫氧镁水泥/聚苯乙烯复合材料,通过氧指数(LOI)测试试验、UL-94垂直燃烧试验、烟密度测试试验、热重分析(TGA)等试验方法,研究不同配比的轻烧氧化镁和七水硫酸镁对聚苯乙烯颗粒燃烧性能的影响。结果表明:保持硫酸镁含量不变,聚苯乙烯复合材料失重幅度随轻烧氢氧化镁含量增加而降低,失重速率随轻烧氢氧化镁增加而减小;最大质量损失率随轻烧氢氧化镁增加而降低,700℃时残炭率随轻烧氢氧化镁含量增加而增大,最大残炭率可达80.73%。硫氧镁水泥包覆的聚苯乙烯颗粒LOI最高可达37.2%,且轻烧氧化镁含量不变,LOI随硫酸镁含量增加而增大;硫酸镁含量不变,LOI随轻烧氧化镁含量增加而增大;硫氧镁水泥包覆聚苯乙烯颗粒的UL-94等级均能达到V-0级别,相比纯聚苯乙烯颗粒烟密度降低约30倍。硫氧镁水泥对聚苯乙烯的阻燃性能和抑烟效果有显著的提高作用。

Study on combustion properties of magnesium oxysulfate cement/polystyrene composites

In order to solve problem that polystyrene is inflammable and easy to produce poisonous gas,magnesium oxysulfate cement and polystyrene particles were used to make magnesium oxysulfate cement/polystyrene composite material.Then,effects of different ratios of lightly-burned magnesium oxide and heptahydrate magnesium oxysulfate on combustion performance of polystyrene particles were studied by LOI test,UL-94 vertical combustion test,smoke density test,and TGA.The results show that when content of magnesium sulfate maintains unchanged,weightlessness range and rate of polystyrene composites decreases with the increase of lightly-burned magnesium oxide,and so does the maximum mass loss rate while residual carbon rate increases with it at 700℃with its maximum rate able to reach 80.73%.LOI of polystyrene coated with magnesium oxysulfate cement can reach up to 37.2%,and it increases along with that of magnesium oxysulfate when lightly-burned magnesium oxide stays fixed.It shows the same trend of LOI increasing along lightly-burned magnesium oxide when the other is unchanged.UL-94 level of composite materials can all reach V-0,and their smoke density is about 30 times lower than that of pure polystyrene particles.Flame retardation and smoke suppression of polystyrene are significantly improved by magnesium oxysulfate cement.