三聚氰胺聚磷酸盐和次磷酸铝协效阻燃高密度纤维板复合材料

Melamine polyphosphate and aluminium phosphinate synergistic flame retardant high density fiberboard composite

将三聚氰胺聚磷酸盐(MPP)和次磷酸铝(AP)阻燃剂添加到木纤维/酚醛树脂(WF/PR)复合材料中,通过人造板热压工艺技术制备阻燃高密度纤维板(MPP-AP-WF/PR)复合材料,探索了MPP和AP组成复配阻燃剂时,MPP-AP-WF/PR复合材料达到最佳阻燃性能时MPP与AP的最佳质量比。采用弯曲强度、吸水厚度膨胀率、吸水率、热失重和极限氧指数(LOI)研究阻燃剂对MPP-AP-WF/PR复合材料的力学性能、耐水性能、耐热性能和阻燃性能的影响,探讨其阻燃机制。结果表明,添加阻燃剂之后,MPP-AP-WF/PR复合材料的力学性能和耐水性能明显降低;而热失重测试结果表明,阻燃剂对MPP-AP-WF/PR复合材料的初始耐热性能没有明显影响,但两者在高温下的协同效应有助于提高残炭量;LOI测试结果表明,单独使用时,MPP比AP具有更好的阻燃效果,当MPP和AP复配使用、MPP与AP的质量比为1∶2时,MPP-AP-WF/PR复合材料具有最好的阻燃效果,这是由于MPP和AP存在协同效用。且SEM和EDS表征发现,MPP-AP-WF/PR复合材料燃烧之后形成致密的含磷酸类物质的炭层,有效阻止了O2和热量进入到炭层的内部,从而提高了MPP-AP-WF/PR复合材料的阻燃性能。

Flame retardant high density fiberboard(MPP-AP-WF/PR)composites were prepared with hot-pressing technology for wood-based products by adding melamine polyphosphate(MPP)and aluminium phosphate(AP)flame retardant to wood fiber/phenolic resin(WF/PR)composite.To investigate the optimum flame retardancy of the MPP-AP-WF/PR composites,the mass ratio of MPP to AP was explored.The effects of the mass ratio of MPP to AP on the mechanical properties,water resistance,thermal stability and flame retardancy of MPP-AP-WF/PR composites were studied based on the bending strength,thickness swelling rate,water absorption,thermogravimetic analysis and limiting oxygen index(LOI),and the flame retardant mechanism was also studied.The results show that the mechanical properties and water resistance of MPP-AP-WF/PR composites decrease significantly with the addition of flame retardant.However,the thermogravimetric results show that the flame retardant has no obvious effect on the initial heat resistance of MPP-AP-WF/PR composites,but the synergistic effect of both flame retardant at high temperature contributes to the carbon residue.LOI test results show that MPP has better flame retardant effect than AP when the flame retardant is used alone.Further,when MPP and AP are used together,the MPP-AP-WF/PR composite has the best flame retardant effect when the mass ratio of MPP to AP is 1∶2.It is due to both flame retardants exhibit the synergistic effect,which can promote the formation of dense char residue containing phosphoric acid compounds after the combustion of MPP-AP-WF/PR composite.The char can effectively prevent oxygen and heat from permeating into the internal carbon layer,thus improving the flame retardancy of the MPP-AP-WF/PR composite.