Flame-retardant wood-plastic composite material and preparation method thereof

The invention discloses a flame-retardant wood-plastic composite material. The flame-retardant wood-plastic composite material consists of the following components in part by weight: 35 to 60 parts of plant fiber, 10 to 35 parts of ammonium phosphate flame retardant, 20 to 28 parts of plastic and 2 to 10 parts of compatilizer, wherein the total parts of the plant fiber, the ammonium phosphate flame retardant, the plastic and the compatilizer are 100; the plant fiber is powder of 30 to 100 meshes of plant fiber; the ammonium phosphate flame retardant is one or a mixture of ammonium hydrogen phosphate and ammonium dihydrogen phosphate; the plastic is one or a mixture of more than two of the following components: polyethylene, polypropylene, acrylenitrile-butadiene-styrene (ABS) plastic and polystyrene; and the compatilizer is one or a mixture of maleic anhydride grafted polyethylene and maleic anhydride grafted polypropylene. The flame-retardant wood-plastic composite material has the advantages of low flame retardant cost, good flame retardant effect and no harm and toxicity.