Topic summary
Thermoset
Extracted from the Wikipedia article Thermosetting polymer.
Properties
Conventional thermoset plastics or elastomers cannot be melted and re-shaped after they are cured. This usually prevents recycling for the same purpose, except as filler material. New developments involving thermoset epoxy resins which on controlled and contained heating form crosslinked networks permit repeatedly reshaping, like silica glass by reversible covalent bond exchange reactions on reheating above the glass transition temperature. There are also thermoset polyurethanes shown to have transient properties and which can thus be reprocessed or recycled.