A method for manufacturing high-performance anti-rust paint using waste polystyrene

Statement of the Problem. Steel corrosion causes 3—4 % of global GDP losses yearly; incumbent primers are petroleum-based, VOC-intensive and increasingly costly. Simultaneously, waste-polystyrene foam accumulates in landfills because it is non-biodegradable and has low recycling value. Results. A dissolution-modification-composite route converted waste-polystyrene into a high-performance coating by substituting 28% alkyd resin with modified polystyrene. The formulation, incorporating n-SiO₂, iron oxide red, ZnO, and triethanolamine, exhibits: withstands 200 h water immersion (≈ 3 × commercial primer); survives > 300 h UV-B (≈ 40 % above 216 h benchmark); retains 2.0 MPa adhesion and 30 kg·cm impact; costs 1792.8 US $ t⁻¹ (8—17 % below domestic/imported grades). 20 kg pilot and 12-month coastal field tests reproduced lab metrics without rust creep or gloss loss. Conclusions. Waste-polystyrene can be valorised into a drop-in, high-performance anticorrosion coating that cuts plastic waste, lowers carbon footprint and meets industrial specifications, offering SMEs a circular-economy pathway.