Polymers (plastics and rubber)
Polymers consist of large molecules organized in chains; proteins and DNA are examples. Polymers used in construction include plastics and materials such as rubber, which are classified as elastomers. They are relatively soft at natural temperatures and hence are elastic.
"Plastics" is a general term for a wide range of synthetic or semi-synthetic organic solids. The word derives from the Greek plastikos meaning "fit for molding," and the malleability of plastics permits them to be shaped by casting, extruding, or pressing. Because of their organic basis (most synthetic plastics are made from hydrocarbons such as oil or coal), they tend to melt at fairly low temperatures.
Plastics and elastomers are both relatively ...