Development of a Thermoplastic Olefin Blend Embo-Pattern Sheet Cross-linked by Electron Beam Irradiation for Luxurious Automotive Interior Parts

Abstract

Many automakers are developing instrument panels with embo-patterns to make more luxurious interior parts for compact cars. The economical male vacuum forming process helps to make parts with embo-patterns price competitive, but embo-pattern loss is greater than that observed with a female vacuum forming process. In the current study, we developed a thermoplastic olefin blend embo-pattern sheet, cross-linked by electron beam irradiation, to minimize embo-pattern loss incurred during part forming in the male vacuum process. The electron beam irradiation dose and materials mixture in the sheet were optimized, improving the retention rate of embo-patterns by almost 3-fold with an electron beam irradiation dose of 80 kGy. At 80 kGy, the product met all property requirements of sheets developed for instrument panel applications and the performance evaluation for airbag deployment. Additionally, this instrument panel production is expected to result in improved price competitiveness, with a savings of more than 10%.

Keywords:

• Automotive interior parts
• Axiomatic design
• Cross-linking
• Electron beam irradiation
• Polymer blends
• Thermoplastic olefin
• Vacuum forming