Warning: Science Content
Polymers are basically a chain made of many molecules. Poly is many and mer is part(s). A partial listing of the elements involved includes carbon, hydrogen, oxygen, chlorine, and sulfer. It is most often thought of as a plastic.
Polymers subsequently fall into two categories; Thermoplastics and Thermosets.
Thermoplastics can be heated and reformed which makes sense because the history of the word plastic (adj) as far back as 1632 is "something that is capable of being formed".
Thermosets on the other hand cannot be remelted. The "set" on the end of this word means "a permanent firming or hardening of a substance as by cooling". "Thermo" means to combine using heat.
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