Anti-yellowing ethylene-vinyl alcohol copolymer (EVOH) and preparation method thereof

The invention provides a preparation method of an anti-yellowing ethylene-vinyl alcohol copolymer (EVOH). The preparation method comprises the following steps: carrying out spray drying on a mixed solution of a main antioxidant, an auxiliary antioxidant, polyethylene wax and a dispersant by using a spray dryer to obtain composite antioxidant particles, and grinding the composite antioxidant particles and a separant into 50-500-mesh high-dispersion antioxidant powder in a planetary ball mill, and uniformly mixing the high-dispersion antioxidant powder, an ethylene-vinyl acetate copolymer (EVA), polyethylene (PE), white carbon black, titanium dioxide and a coupling agent in a screw extruder, and carrying out extrusion granulation to obtain the anti-yellowing high-dispersion master batch. And finally, uniformly mixing the anti-yellowing high-dispersion master batch with an ethylene-vinyl alcohol copolymer (EVOH) in a screw extruder, and carrying out extrusion granulation to obtain an anti-yellowing EVOH product.