Study On Flame Retardancy Of Pine Wood Modified By Ammonium Polyphosphate And Compound Flame Retardant

In the contemporary society of sustainable development,wood has been widely concerned with its unique features such as renewable,appearance,biodegradable and easy to process.The hydrocarbon content of wood is very high and it’s easy to burn,so there are some potential safety problems in industrial production and life.The development and application of wood is limited,so it is of great significance to study and improve the flame retardancy of wood.Based on the literature survey,this research figure out the research direction of the flame retardation performance improvement for the wood materials.The fire retardant is based on the Ammonium polyphosphate(APP)Phase Ⅱ with the over 1000 degree of polymerization.Then the fire retardation base is processed by the surface modification with the Silane coupling agents and build a compound system with the mixture of boracic acid and borax.Finally,the flame retardant pine samples can be made by the dip method with the pre-processed base.After the surface modification with Silane coupling agents(KH-550),the change of APP’s structure and heat tolerance can be observed by the XRD,FTIR and Thermogravimetric Analysis(TGA).The result shows that the KH-550 has a significant effect at the dispersion of the Liquid paraffin.The addition of the KH-550 improve the oil-soluble performance.With the analysis based on XRD and FT-IR,the KH-550 has less effects on the crystal structure of the APP,however,some functional groups has grafted onto the APP and the property has changed.After taken the TGA,the APP’s flame retardation has been slightly improved.With the mixture of boracic acid and borax and the flame retard process via dip method,the pine samples are finally completed and analyzed by the TG and LOI to illustrate the fire retardation performance.The result shows that in the carbonization state,the sample’s weight loss rate is 49.38%,the TG peak is 293.65℃.In the calcination stage,the charring rate is 28.46%,and the oxygen index is 34.2.Comparing to the pine samples without the preprocess or the samples only added APP,in the carbonization state,the weight loss rate and TG peak significantly decrease.In the final stage the charring rate also increases obviously.Thus,the result show the APP Phase Ⅱ with the mixture of boracic acid and borax has a good performance as the fire retardant.