User:KDS4444/Cyclomethicone

Cyclosiloxane is a class of volatile methyl or phenyl siloxanes which are liquid silicones (cyclic polydimethylsiloxane and polydiphenylsiloxane polymers) that possess the characteristics of low viscosity and high volatility as well as being skin emollients and in certain circumstances useful cleaning solvents. Unlike dimethicones, which are linear siloxanes that do not evaporate, cyclosiloxanes are cyclic: both consist of a polymer featuring a monomer backbone of one silicon and two oxygen atoms bonded together, but dimethicones have a long "linear" backbone surrounded by a series of methyl groups (which produces a clear, non-reactive, non-volatile liquid ranging from water-thin to taffy-thick), whereas cyclosiloxanes have short backbones that make closed or nearly-closed rings or "cycles" with their methyl groups, giving them many of the same properties of dimethicones but making them much more volatile. They are used in many cosmetic products where eventual complete evaporation of the siloxane carrier fluid is desired. In this way they are useful for products like deodorants and antiperspirants which need to coat the skin but not remain tacky afterward. Most cyclomethicone is manufactured by Dow Corning.

There are several kinds of cyclosiloxanes, including the following:


 * Decamethylcyclopentasiloxane
 * Pentamethylcyclopentasiloxane ($$\text{D}^{\text{Me}}_{\text{5}}$$)
 * octamethylcyclotetrasiloxane(D4)
 * octaphenylcyclotetrasiloxane
 * dimethyl cyclosiloxane (DMC)
 * dimethyl diphenyl cyclosiloxane (DMDPC)
 * hexamethylcyclotrisiloxane(D3)
 * dodecamethylcyclohexasiloxane (D6)
 * Trimethytriphenylcyclotrisiloxane
 * Tetramethyltetraphenylcyclotetrasiloxane
 * tetradecamethylcycloheptasiloxane(D7)
 * octaalkylcyclotetrasiloxane
 * tetramethylcyclotetracyclisiloxane
 * hexamethylcyclohexasiloxane