Polydimethylsiloxane (PDMS) belongs to a group of polymeric organosilicon compounds which are commonly referred to as silicones. PDMS is the most widely used silicon-based organic polymer, and is particularly known for its unusual rheological (or flow) properties. Its applications range from contact lenses and medical devices to elastomers, in shampoos (as dimethicone makes hair shiny and slippery), caulking, lubricating oils and heat resistant tiles.
PDMS is optically clear, and is generally considered to be inert, non-toxic and non-flammable. It is occasionally called dimethicone and is one of several types of silicone oil (polymerized siloxane).