According to Wikipedia, here's the 411 on ingredient #19:
"Polydimethylsiloxane (PDMS) belongs to a group of polymeric organosilicon compounds that 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. PDMS is optically clear, and, in general, inert, non-toxic, and non-flammable. It is also called dimethicone and is one of several types of silicone oil (polymerized siloxane). Its applications range from contact lenses and medical devices to elastomers; it is also present in shampoos (as dimethicone makes hair shiny and slippery), food (antifoaming agent), caulking, lubricants, and heat-resistant tiles."
I know dimethicone as a anti-frizz ingredient in commercial products for curly hair ("makes hair shiny and slippery"). I've also seen it in dry-skin lotion to make your skin shiny and slippery, just like nature intended it to be.
