Effects of Aluminum Phosphate on the Fire-Retardant and Mechanical Properties of Wood Flour/HDPE Composite
The wood flour/HDPE composites (WF/HDPE) was modified with aluminum phosphate (AHP) as flame retardant.The flame retardant properties of WF/HDPE composites were studied by UL-94,limiting oxygen index (LOI),cone calorimeter test (CCT),and mechanical properties were studied by measurements of tensile strength,unnotched impact strength and flexural strength.The flame retardant mechanism of AHP was investigated by thermogravimetric analysis (TGA) and scanning dectron microscopy (SEM).The results show that,AHP,WF and the bound water in WF construct an intumescent flame-retardant.When the mass fraction of AHP is 30 %,WF/HDPE composite achieves UL-94 V-0 rating,the oxygen index reaches 25.5% and the flame retardant property is improved significantly.However,mechanical properties of WF/HDPE composites decrease to some extent due to addition of AHP.