Influence of particle size and addition of recycling phenolic foam on mechanical and flame retardant properties of wood-phenolic composites

To recycle the thermoset phenolic foam (PF) wastes, a new flame-retardant panel was developed using milled PF particles and natural wood fibers (WB). PF particles were smashed into three particle size, pre-modified and blended with the sizing fibers in five wt% contents (0, 10, 20, 30, 40%). Each type of mixtures was hot-pressed at same temperature. Physical, mechanical and flame-retardant properties of WB-PF composites were investigated. The mechanical properties of WB-PF composites were found to be rapidly declined with the increasing proportion and size of PF particles. There was also a progressive decrease in thickness swelling for the boards with increasing addition of PF particles. The ultimate fire-retardant property of the boards was remarkably enhanced with more addition and smaller size of PF particles. Among the WB-PF composites, panel with 30 wt% of PF particles had optimum results. The final board with good physical-mechanical and fire-retardant properties can find application in fields like muti-functional furniture, construction, house ware, etc.