邻苯二胺基环三磷腈阻燃剂在EVA材料中的性能及机理研究

Properties and Mechanism of Tri(o-phenylenediamine)-cyclotriphosphazene Flame Retardant in EVA

应用混料设计实验方法研究了邻苯二胺基环三磷腈(HACTP)和聚磷酸铵(APP)、蒙脱土(MMT)复配阻燃剂对乙烯-醋酸乙烯酯共聚物(EVA)材料阻燃和力学性能的影响,并利用锥形量热仪及电子扫描显微镜研究了不同配方下阻燃EVA的热释放性能和燃烧后膨胀炭层的微观形貌,探讨阻燃机理。结果表明:在HACTP质量分数为32.84%、APP质量分数为50.04%、MMT质量分数为17.12%的配方下,阻燃EVA通过UL 94 V-0,极限氧指数为36.8%,拉伸强度为5.46 MPa,断裂伸长率为594.95%。该阻燃剂在材料表面形成连续致密的炭层,有效抑制了材料的降解,显著降低燃烧过程中的热释放量,减少火灾危险性,发挥了凝聚相阻燃作用。

The effects of flame retardants composed of tri(o-phenylenediamine)cyclotriphosphazene(HACTP),ammonium polyphosphate(APP)and montmorillonite(MMT)on the flame retardancy and mechanical properties of ethylene vinyl acetate copolymer(EVA)were studied by design of mixture experiment.The heat release properties of flame retardant EVA and the micro morphology of the expanded carbon layer after combustion were studied by cone calorimeter and scanning electron microscope,and the mechanism of flame retardant was discussed.The results show that the flame retardant EVA can reach UL 94 V-0,the limiting oxygen index is 36.8%,the tensile strength is 5.46 MPa and the elongation at break is 594.95%under the formulation which the mass fraction of HACTP is 32.84%,the mass fraction of APP is 50.04%,the mass fraction of MMT is 17.12%.The flame retardant forms a continuous dense carbon layer on the surface of the material,which effectively inhibits the degradation of the material,significantly reduces the heat release during the combustion process,reduces the fire risk,and plays the role of condensed phase flame retardant.