Polysiloxanes

Part of speech: noun

Definitions

1. Polymers built from a repeating chain of silicon and oxygen atoms, with organic groups attached to the silicon, widely used in sealants, lubricants and medical devices
2. Long-chain synthetic materials whose backbone alternates silicon and oxygen atoms, valued for flexibility, heat resistance and water repellence in many industrial products
3. Macromolecular substances containing a silicon-oxygen main chain, a class of silicones employed in coatings, elastomers and biomedical applications

Etymology: Polysiloxanes are a family of synthetic polymers, and their name is built from two parts that come from very different corners of the language. The "poly-" comes from ancient Greek "polús", meaning "many", which has been used in English chemistry as a prefix for chains made of repeating units. The rest, "siloxane", is a much newer coinage: it blends "silicon" with "oxygen", the two elements that form its backbone of alternating silicon and oxygen atoms. So the word is a simple compound rather than a traditional inherited term. Chemists added "poly-" to "siloxane" to name the long-chain form, meaning a molecule built from many siloxane units joined together. The plural "polysiloxanes" simply refers to the whole class of these materials. Because the name describes structure rather than a historical usage, its meaning has stayed fixed since it was introduced: many silicon-oxygen units strung into one chain.

Synonyms: silicones