1. Polymer properties before painting

The competition between metals and plastics for appearance parts is fierce. This is particularly true for automotive body parts (see [AM 3 591] Plastics and automobiles). For example, until 1970, all bumpers were made of chromed metal, whereas today they are made exclusively of plastic, usually painted. Interior parts (center console, gear knob, etc.) and exterior parts (fenders, tailgates, handles) are also often made of painted plastic. Computer accessories (screens, scanners, printers, etc.) and cell phones are now generally made of painted plastics. What all these objects have in common is the combination...