General Characteristics of Amorphous Engineering Plastics General purpose structural parts Moderate strength Moderate temperature Good dimensional stability Good Izod impact Easily fabricated Amorphous engineering plastics can be considered for applications with an approximate maximum temperature of 250°F. Selecting a plastic material for use in a high temperature environment requires careful review of material properties data. View our interactive Thermoplastics Triangle to compare materials. Explore Amorphous Engineering Plastics Noryl® Engineering plastic with outstanding strength, stiffness, and electrical insulating properties. Polycarbonate Transparent, strong and stiff thermoplastic with outstanding impact resistance.