胍类阻燃剂处理木材的热解机理

Thermal Degradation Mechanism of Wood Treated by Guanidine Flame Retardants

为了研究木材热解行为与阻燃性能的关系,探讨其热解机理,将木材用一系列胍类阻燃剂进行阻燃处理,所得阻燃木材采用热重(TG)、差热分析(DTA)和红外光谱(IR)进行分析,并用Broido方程计算木材的热解活化能.结果发现,经磷酸二氢胍和磷酸氢二胍处理的木材阻燃性较好,氧指数为39%～42%;主要热解阶段在低于300℃进行,热解表观活化能降低约60 kJ/mol,这主要是由于木材在低于300℃热解主要发生脱水、重排交联炭化产生少量可燃性气体,剩炭增加.而经碳酸胍、硝酸胍处理的木材样品虽然其主要热解阶段温度降低,但阻燃性差,氧指数小于26%,主要是由于其热解仍然包括1个较高温度阶段(300℃以上),在此阶段热解产生较多的可燃性气体.

To study the correlation between thermal degradation behavior and flame retardation of wood and the mechanism of the thermal degradation,wood was treated with guanidine flame retardants.The samples were subjected to thermogravimetry(TG)、differential thermal analysis(DTA)and IR spectra.Moreover, activation energies of thermal degradation were obtained following the Broido equation.The date show that, wood treated by guanidine dihydrogen phosphate and diguanidine hydrogen phosphate obtain good flame retardati...