Rigid polyurethane foams reinforced with ultrafine powder from automotive shredder residue

Abstract

AbstractWith the booming of the abandoned cars, automobile shredding residual (ASR) increase sharply in recent years. ASRs contain complex components that are difficult to separate and recycle, causing serious environmental impacts. Herein, we report a new strategy for ASR recycling to prepare high value‐added rigid polyurethane foams (RPUFs) with excellent mechanical and thermal properties. Ultrafine ASR powder with homogeneous domain size and activated functional groups, added to the precursor of RPUFs as reinforcing fillers, was fabricated through solid‐state shear milling (S3M) technology. As a nucleating agent, ASR particles can participate in the foaming procedure of RPUFs, which decreased the cell size to ~0.2 mm. Owing to the strong interaction between the ASR and polyurethane matrix, the thermal degradation temperature increased to 246.7°C, 42.4°C higher than the neat one. Inspiringly, the ASR particles can act as reinforcing elements in the cell walls, which can not only increase the compressive strength and modulus to 1.79 and 0.1 MPa respectively, 81% and 71% higher than the neat sample, but also enhance the long‐term fatigue resistance of the foam. This strategy achieves the recycling and utilization of ASR, and expands the application scope of RPUFs as well.