plastics (thermosets) refer to a variety
of polymer materials
that cure, through the addition of energy,
to a stronger form. The energy may be in
the form of heat (generally above 200 degrees Celsius),
through a chemical reaction (e.g., two-part epoxy),
Thermoset materials are usually liquid,
powder, or malleable prior
to curing, and designed to be molded into
their final form, or used as adhesives.
The curing process transforms the resin into
a plastic or rubber by cross-linking.
Energy and catalysts are
added that cause the molecular chains to link
into a rigid, 3-D structure.
A thermoset material cannot be melted and
re-molded after it is cured.
Thermoset materials are generally stronger
than thermoplastic materials,
and are also better suited to high-temperature applications.
They do not lend themselves to recycling like
thermoplastics, which can be melted and re-molded.
Methods used to mould thermosets