Recent Chemical and Reinforcement Development in the Reinforced Reaction Injection Molding Process for Automobile Applications

Abstract

Since the early 70’s, fascias and bumper covers produced by the RIM (Reaction Injection Molding) process have been extensively used in the automobile industry. The advantages of high impact, class “A” surface and light weight merit consideration for volume usage by the industry. Yet the application has its limitations, the fascia materials are relatively poor in heat resistance and thermal expansion characteristics. Recent development work to improve the heat resistance and thermal expansion properties by adding reinforcement agents in the materials were carried out. At the same time RIM equipment that can handle abrasive fillers was being developed. Oldsmobile Division, General Motors Corporation, is the first automobile division to utilize the concept of RRIM (Reinforced Reaction Injection Molding) in designing a fender application for their 1981 “Sport Omega.” This paper is the summary of the development work in material evaluation for the RRIM fender application. Also, Olds-mobile Division recognizes the limitations of the fascia material in heat resistance and thermal expansion properties; a RRIM fascia material development was also carried out within the Division to improve the quality of the product in fascia application.