A thermoplastic polymer is one that can be repeatedly softened by heating and hardened by cooling.
In the softened state it can be shaped by injection, extrusion or moulding.
Thermoplastics are by far the most commonly used polymers. They are transformed without any chemical reaction, unlike thermosetting polymers.
The rate of transformation of these polymers is almost exclusively linked to their cooling rate and is therefore faster than that of thermosets or elastomers.
The most commonly used ones are:
• thermoplastic polyesters;
• polyphenylene oxide;
• polyacetals (polyoxymethylene);
• polyether ether ketones (PEEK);
• polysulphides (PS).