Materials that undergo a chemical crosslinking reaction going from liquid to solid or semi-solid. This reaction is irreversible. Typical thermosets are polyesters, acrylics, epoxies, and phenolics.
Materials that may not be reheated and softened again. Once the structural framework is set, these plastics cannot be reformed.
Resins or plastic compounds which in their final state as finished articles are substantially infusible and insoluble.
and thermoplastics: the two major families of plastic materials. During hot forming, covalent bonds are created in thermosets thus irreversibly uniting the chains (reticulation). Thermoplastics can undergo hot "remodelling" during which the temperature only softens them
Type of polymer which does not soften appreciably when heated.
Plastics which once molded cannot be reformed using heat or pressure.
Thermosetting resins or polymers formed by chemical cross-linking which renders them permanently solid. This reaction is irreversible and, unlike thermoplastics, thermosets do not melt when heated. Typical thermosets are polyesters, acrylics, epoxies, phenolics and vinyl esters.
Resins or plastic compounds, which in their final state are infusible and insoluble. After being fully cured, thermosets cannot be resoftened by heat.
Materials that cannot be remelted once they have been made into their initial shape. Epoxies, phenolic resins, and most natural rubber products are included in this category.