Two Families of Plastic

All plastic can be divided into two types: remeltable and non-remeltable.

THERMOPLASTIC

Thermoplastic molecule chains are linked by strong bindings, but between the chains, there is only entanglement and weak physical bindings. When heated, the chains hence lose contact, making the material melt.

THERMOSET PLASTIC

In thermoset plastic, the molecule chains are linked by strong, crisscross, chemical bindings. Thermoset plastic cannot be remelted, as the energy required destroys the material.