Thermosetting polymers - Classification of polymers

These are the polymers which go through permanent modification on heating. They get firm and infusible on heating. They are generally built from low molecular mass semifluid molecules. While heated they went highly cross linked to make hard infusible and insoluble components. The cross links take the atom in place that is why heating does not permit them to move liberally. Thus a thermosetting plastic is cross linked and is lastingly rigid.