Characterization of mechanical and temperature effects on delamination and basic strength behaviors of PVC coated PUR foam substrate used in bus dashboard

Abstract

This study focuses on the delamination and characterization of different loadings and temperature conditions of polyvinyl chloride (PVC)-coated polyurethane (PUR) foam component layers commonly used in bus dashboards. The method was developed through mechanical and thermal tests. The study involves the examination of primer and no primer PVC-coated PUR components using SEM (Scanning Electron Microscope), tensile-compression, three-point bending, primer characterization, peel, PUR material thermal expansion, and thermal tests. Physical and material tests were conducted to determine the mechanical properties of PVC and PUR foam and the material properties of the primer. Fourier transform infrared spectroscopy (FTIR) analysis was also conducted to identify the functional groups present in the PVC, PUR, and primer materials, helping to understand the material interactions. Some tests produced the expected results, while others did not. The primer characterization and three-point bending tests were unsuccessful due to sample foam breakage. However, tensile-compression tests, peel tests, thermal expansion tests, and thermal tests yielded the desired outcomes. During thermal testing of primed samples, it was observed that the samples shortened and bent as the primer material melted and began to separate from the PVC and PUR layers. This bending and swelling were attributed to the difference in thermal expansion coefficients between the melting primer material and the PVC and PUR layers. The results demonstrate that PVC-coated PUR components can be effectively separated, and they also highlight opportunities for design modifications to improve the durability of bus dashboards.