
Octamethylcyclotetrasiloxane (D4)
Chemical Name: | Octamethyl cyclotetrasiloxane |
Product Category: | Silicone Intermediate – Product |
Structural Formula: | ![]() |
CAS No.: | 556-67-2 |
EINECS: | 209-136-7 |
Molecular Formula: | C8H24O4Si4 |
Molecular Weight: | 296 |
OctamethylcyclotetrasiloxaneDescription
Octamethylcyclotetrasiloxane (D4) CAS 556-67-2 is a flammable, odorless, and colorless transparent or milky white liquid. It is produced through the hydrolysis of dimethyldichlorosilane, followed by separation and rectification, making it a crucial intermediate in the silicone industry.
D4 is primarily used in the production of silicone polymers, including methyl silicone oil, and serves as an insulating and moisture-resistant agent for radio components. Additionally, it is used as a surface deactivation agent for gas chromatography glass capillary columns.
Equivalent Product Name | NA |
Alias | Octamethyl cyclotetrasilazane; octaphenyl silsesquioxane; Octamethylcyclotetrasiloxane; |
Relative density | 0.9558 |
Melting point | 17~18℃ |
Boiling point | 175~176℃ |
Refractive index | (n20D) 1.3968 |
Flash point | 60°C |
Properties | Colorless oily liquid. |
Sensitivity | Sensitive to moisture. |
Water Solubility | Miscible with organic solvents, insoluble in water. |
Uses | The primary form of dimethylcyclosiloxane is mainly used for ring-opening polymerization to form silicone oil, silicone rubber and silicone resin with different degrees of polymerization. These polymers are further processed into products that are widely used in various fields such as construction, electronics, textiles, automobiles, personal care, food, and mechanical processing, and there are also a small amount of direct applications. |
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Octamethylcyclotetrasiloxane : Guide
Octamethylcyclotetrasiloxane (D4) CAS 556-67-2 is a key raw material for silicone oil, silicone emulsion, silicone rubber, and silicone resin. It is also used as a rubber filler treatment agent and a cosmetic ingredient.
D4 is widely applied in the electronics industry for manufacturing high tear-resistant silicone rubber and is an essential intermediate in the synthesis of various silicone polymers. It also serves as an insulation and moisture-resistant agent for radio components.
D4 is miscible with organic solvents, soluble in carbon tetrachloride, and almost insoluble in water. It has a melting point of 17-18°C, boiling point of 175-176°C (760 mmHg), density of 0.956-0.959 g/mL (20°C), refractive index of 1.395-1.398 (n20/D), and a flash point of 55°C (131°F).