Abstract: An emulsion type waterproof coating was prepared with acrylic acid and butyl acrylate grafted waste PS foam as the main raw material. The effects of initiator loading, monomer ratio, reaction temperature, and reaction time on the grafting rate of PS were studied. It was found the optimal recipe was: PS 30 g, solvent 60 mL, initiator 2.2 g, monomer 20 g, filler 10 wt %, plasticizer 4 wt %, both based on the weight of grafted PS, the reaction temperature 85 ℃, the reaction time 2.5 h. The waterproof time was 25 h; the time of torlerance of salinity was 27 h, the dry time was 18 min, and the impact strength was 50 kg·cm.

Key words: polystyrene, foam, graft modification, waterproof coating