Eco-friendly wood-plastic composites from laminate sanding dust and waste poly(propylene) food pails

Plastic pollution caused by non-degradable petrochemical-based plastics has become a serious environmental problem in China, and the reasonable management of industrial waste and renewable resources remains a huge challenge. Here, we report environment-friendly wood-plastic composites (WPCs), prepared from decorative high-pressure laminate (HPL) sanding dust (filler) and waste thermoplastic food pails (matrix), as well as comprehensively evaluate the processability, mechanical and interfacial properties, indoor safety evaluation. The elemental composition and thermal stability of these two residue materials were suitable for the WPC manufacturing process. The content of HPL sanding dust in WPC was fixed at 60 wt%, and the amount of maleic anhydride grafted polypropylene (MAPP) added was 5 wt%-7 wt%, which maximized the utilization of waste resources, and can obtain impact strength as high as 5-6 kJ/m², tensile strength of 35-42 MPa and flexural strength as high as 43-46 MPa. The developed WPCs had low formaldehyde emissions (≤1.53 mg/m³) and slightly improved flame retardancy. Finally, their lower cost (5,035 yuan/ton) and higher eco-efficiency (12.81 yuan/kg CO₂) characteristics allowed them to be compatible with the current sustainable development requirements. This study provides a novel approach for the utilization of industrial waste and recyclable resources for sustainable replacement of wood-based products.