D4 is referred to as octamethylcyclotetrasiloxane for short. It is a colorless transparent or milky white liquid, flammable and odorless. It is a compound obtained by separation and rectification based on the product prepared by the hydrolysis synthesis process of dimethyldichlorosilane. It is an important intermediate in the silicone industry and is mainly used for the preparation of silicone polymers such as methyl silicone oil.
D4 is also one of the important raw materials of organosilicon softener for textiles.

D5 is decamethylcyclopentasiloxane.

D6 is dodecyl cyclohexane, which is colorless transparent oily liquid, volatile and low viscosity silicone oil.

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