▎ 摘　　要

NOVELTY - Long-lasting antibacterial and mildew proof polypropylene (PP)/polystyrene (PS) plastic comprises polypropylene masterbatch, polystyrene masterbatch, antibacterial and mildew-proof agent, microcrystalline cellulose, plasticizer, toughening agent, antioxidant and ultraviolet absorbent. Where the antibacterial and mildew-proof agent comprises 2-5 wt.% graphene oxide/silver nanocomposite and 3-7 wt.% natamycin. USE - Used as long-lasting antibacterial and mildew proof polypropylene/polystyrene plastic. ADVANTAGE - The method uses microbeads to improve the antibacterial and mildew proof properties of plastics through the mechanism of silver ion antibacterial and titanium dioxide photocatalytic antibacterial respectively, improves compatibility of the microbeads using plastic substrate, does not affect the mechanical properties of the plastic, and has good application prospect. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing long-acting antibacterial and mildew resistant PP/PS plastic, comprising (i) adding PP masterbatch, PS masterbatch, antibacterial and mildew-proof agent, microcrystalline cellulose, plasticizer, toughening agent, antioxidant, and ultraviolet absorber into double-screw extruder for mixing, and (ii) conveying the material to single-screw extruder for extruding and granulating to obtain long-acting antibacterial mildew-proof PP/PS plastic. Where the four temperature sections in the mixing and extruding process is as follows: the feeding section temperature is 110-120 degrees C, the conveying section temperature is 125-135 degrees C, the melting section temperature is 135-145 degrees C, and extruding section temperature is 140-150 degrees C.