Petra Endurance Enhanced glass-fiber-reinforced thermoplastic polyester resins are said to provide a balance of high fatigue strength and good surface appearance that’s typically unavailable with compounds with high glass-reinforcement levels. They particularly suit the molding of chairs and armrests, where they eliminate the need for painting. Fatigue strength reportedly is typically 10 to 50 times higher than other glass-filled polyesters.
Development grade 7537 promises over 1.7 million cycles at an 8000-psi loading, compared to 26,000 for a standard 30% glass-filled PET. A special additives package provides a high-quality surface appearance. Materials in the 7300 series include post-consumer polyester recyclate, while the 7500 series has virgin grades.
The materials are claimed to offer excellent melt stability and high melt flow, thus providing a broader processing window than other highly reinforced polyesters. They can produce large parts as well as thinwalled ones using molds with small gates. Black, natural, and precolored grades are available. Honeywell Plastics, 101 Columbia Rd., Morristown, NJ 07962 www.honeywell-plastics.com