Preparation method of non-intrinsic flame-retardant and high-strength polyester industrial yarns

The invention relates to a preparation method of non-intrinsic flame-retardant and high-strength polyester industrial yarns. The preparation method comprises the following steps of firstly, carrying out melt blending on polyethylene glycol terephthalate and a polyester type macromolecular flame retardant to prepare flame-retardant polyester chips, and then carrying out metering, melt spinning, cooling, oiling, stretching, heat setting and winding on the flame-retardant chips. The prepared non-intrinsic flame-retardant and high-strength polyester industrial yarns have the limit oxygen index being greater than or equal to 31% and the breaking strength being 7.4-8.0 cN/dtex; and 190T plain weave cloth is woven by a shuttle machine, and the vertical combustion damage lengths of the 190T plain weave cloth in the weft and warp directions are both less than 3 cm. The polyester type macromolecular flame retardant is adopted as a flame-retardant functional unit, has a good flame-retardant effect, and also solves the p