Effect of dipping treatment on flame retardant property of poplar plywood

In order to explore the production process, fire retardant properties and mechanical properties of retardant poplar plywood, this paper, with poplar veneer as testing material, centers on the manufacture of flame-retardant plywood by the use of ammonium polyphosphate flame retardant. The optimized impregnation process of veneer was explored by oxygen index method and photometry. The fire retardant properties of plywood were studied by cone calorimeter method. It was showed that: the optimized of veneer impregnated process was taking soaking temperature of 40 °C, soaking time of 0.5 h and impregnated concentration of 20%. APP flame-retardant could significantly shorten the combustion duration time of poplar plywood and greatly reduce the heat release rate, total smoke release as well as the mass loss rate, and thus obviously enhance the mass of combustion char residue, which reflected the fact that the APP flame retardant had a significant retardant effect. But the total increasing smoke emission also indicated that smoke-suppression property of APP flame retardant still needed to be improved. Through a comprehensive analysis on APP, we could see that it was a better flame retardant.