生物基阻燃水性聚氨酯涂料的制备及对胶合板性能的影响

Preparation of bio-based flame-retardant waterborne polyurethane coatings and their impact on plywood properties

针对包装、建筑和家具领域使用的胶合板易燃的问题,对胶合板进行阻燃处理,利用蓖麻油、马来酸酐、异佛尔酮二异氰酸酯、季戊四醇、三乙胺、硼酸锌、丙酮、乙二胺,通过丙酮法制备生物基阻燃水性聚氨酯乳液,采用浸渍涂布法制备阻燃杨木胶合板。根据GB/T 1040.3—2006对水性聚氨酯胶膜的物理性能进行测试,采用傅里叶变换红外光谱表征硼酸锌添加量不同的乳液的官能团,采用氧指数测定仪、热重分析仪、锥形量热仪、导热系数测试仪表征阻燃处理前后杨木胶合板的阻燃性能、热稳定性、热释放速率和隔热性能,并探究了阻燃杨木胶合板的抗流失性能。结果表明:阻燃杨木胶合板具有良好的阻燃性能,当硼酸锌添加量达到7.5g时阻燃杨木胶合板的极限氧指数可达34.8%,残炭率较对照样提高了360.94%,最大热释放速率降低了24.10%,总热释放量下降了43.32%,总烟释放量下降了37.50%,导热系数下降了24.14%,同时抗流失性也有所提升。生物基阻燃水性聚氨酯乳液可以增强杨木胶合板的阻燃性能,较直接添加硼酸锌具有更好的抗流失性,可以为胶合板提供更持久的阻燃效果。

To solve the flammable problem of plywood used in packaging,construction and furniture,the plywood was treated with flame retardant.A bio-based flame-retardant waterborne polyurethane emulsion was prepared by the acetone method using castor oil,maleic anhydride,isophorone diisocyanate,pentaerythritol,triethylamine,zinc borate,acetone and ethylenediamine,and the flame-retardant poplar plywood was prepared by the impregnation coating method.The physical properties of the waterborne polyurethane film were measured according to GB/T 1040.3—2006,and the functional groups structure of the emulsions with different additions of zinc borate were characterized by Fourier transform infrared spectroscopy.Limiting oxygen index tester,thermogravimetric analyzer,cone calorimeter,and thermal conductivity tester were used to characterize the flame-retardancy,thermal stability,heat release rate,and thermal insulation properties of poplar plywood before and after flame-retardant treatment.In addition,the loss resistance of the flame-retardant poplar plywood was investigated.The results showed that flame-retardant poplar plywood had good flame retardancy.When the addition of zinc borate reached 7.5g,the LOI of the plywood reached 34.8%,the residual carbon rate increased by 360.94%compared with the control,the maximum heat release rate decreased by 24.10%,the total heat release decreased by 43.32%,the total smoke release decreased by 37.50%,the thermal conductivity decreased by 24.14%,and the loss resistance was also improved.The bio-based flame-retardant waterborne polyurethane emulsion could enhance the flame retardancy of poplar plywood,and also had better loss resistance than the direct addition of zinc borate,which could provide a longer-lasting flame-retardant effect for the plywood.