Amorphous machinery parts

Lubricity of crystalline polymers is usually higher than that of amorphous polymers. Excellent machinery parts are made from crystalline nylon-6,6 resins, eg, gears, cams, wedges, and other components not requiring lubrication. Gears made of amorphous polyimide resin, on the other hand, do not exhibit this feature. 

SAN, styrene I acrylonitrile plastics. Copolymer of styrene and acrylonitrile. An amorphous thermoplastic, transparent in the original form, which is tougher, less brittle, somewhat more heat stable than the standard polystyrene. Applications transparent covers of car and signal lamps, machinery and instrument parts, and various consumer goods. Trade names Kostil (I), Luran (FRG), Lustran (USA), Tyril (USA). 

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