Preparation method of graphene based reinforced and flame-retarded recycled polyester staple fiber

The invention provides a preparation method of a graphene based reinforced and flame-retarded recycled polyester staple fiber. The method comprises the following steps: preparing graphene master batch; preparing phosphate based halogen-free flame retardant master batch; weighing the graphene master batch and the phosphate based halogen-free flame retardant master batch, mixing with a recycled polyester raw material, drying, feeding molten dried raw materials into an impurity removal stirrer under the action of a screw extruder by a melt pump for carrying out homogenization impurity-removal treatment, feeding a homogenized and impurity-removal polyester melt into a secondary filter by the melt pump, enabling a filtered melt to pass through a mixed melt on a pipeline to enter a spinning manifold, carrying out drafting processing on a spun fiber to obtain the reinforced and flame-retarded recycled polyester fiber, cutting off bundles and packaging. The reinforced and flame-retarded recycled polyester chip has the good spinning forming property, the fiber quality is high, the using amount of a fire retardant can be effectively reduced under the synergistic effect of grapheme and the phosphate based flame retardant, the cost is reduced, the reinforcement effect can be achieved and the mechanical property of the fiber is effectively improved.