Silane Coupling Agents Octamethylcyclotetrasiloxane (D4)
Product Name: Octamethylcyclotetrasiloxane (D4 )
Molecular Formula: (CH3 ) 8 Si4 O4
CAS No.: 556-67-2
Physical and Chemical Properties:
Freezing Point: 17~18℃
Boiling Point: 175-176℃
Flash Point: 60℃ Relative Density（water=1）: 0.956
Appearance: Colorless transparent liquid without visible impurity
Technical Data of Octamethylcyclotetrasiloxane
It is colorless, inflammable, and can not dissolve in water, but dissolve in organic solvents such as benzene, etc. It can be used to synthesize organic silicon polymer by acid or alkali catalysis to manufacture silicone oil, silicone rubber, etc. It can also be used directly as a treating agent for rubber stuffing and the raw material for cosmetics.
Preparation Method of Octamethylcyclotetrasiloxane
Dimethyl dichlorosilane is added dropwise to water, the temperature is maintained at 30-40℃, stratified, the acidic water is released, the oily substance is hydrolyzed with sodium hydroxide solution, the hydrolysate and 0.5%-2% potassium hydroxide are added into the cracking kettle and cracked at 120-140℃ and 99.8kPa vacuum. The cracked material is fractionated and the fraction is collected at 173-176°C to obtain octamethylcyclotetraoxysilane.