What is Thermoplastic?
[[File:Milk crate.jpg|thumb|[[Polyethylene]] crate]] A '''thermoplastic''' is a material, usually a [[plastic]] [[polymer]], which becomes more soft when heated and hard when cooled. Thermoplastic materials can be cooled and heated several times without any change in their chemical or mechanical properties. When thermoplastics are heated to their [[melting point]], they melt to a [[liquid]]. They freeze to a glassy state when cooled below their [[glass transition]] temperature. Thermoplastic materials have many features. Some products made from thermoplastic materials are used for [[electronics|electronic]] applications. They protect against [[electrostatic]] discharge and [[radio]] [[frequency]] interference. Thermoplastics are one of the main two types of [[plastic]]s. <ref>{{Cite web|title=Thermoplastics - an overview {{!}} ScienceDirect Topics|url=https://www.sciencedirect.com/topics/materials-science/thermoplastics|access-date=2023-02-04|website=www.sciencedirect.com}}</ref> Thermoplastic can be [[moulding|moulded]] into any shape. Thermoplastics differ from [[thermosetting polymer]]s. Thermosets form irreversible [[chemical bonds]] during the [[curing (chemistry)|curing]] process, and won't melt. == Types of thermoplastics == '''PET ([[polyethylene]] terephthalate)''' :- Light, rigid or semi-rigid, naturally transparent or colorless, PET is an excellent moisture and gas barrier and is resistant to impacts. It is one of the most easily recyclable plastics and is used to produce bottles, bags and synthetic fibers for clothing. '''HDPE (high-density polyethylene)''' :- HDPE is translucent, strong and easy to process, resistant to impacts and non-toxic. It is used to make bottles, tanks, bins and containers for transport. <ref>{{Cite web|last1=October 29|first1=Professor Plastics Article updated on|last2=2018|date=2015-05-21|title=High Density Polyethylene (HDPE): So Popular|url=https://www.plasticsmakeitpossible.com/about-plastics/types-of-plastics/professor-plastics-high-density-polyethylene-hdpe-so-pop