Octamethylcyclotetrasiloxane (D4)

Octamethylcyclotetrasiloxane (D4) is a cyclic siloxane compound with the chemical formula [(CH₃)₂SiO]₄. It features four repeating dimethylsiloxane units in a stable ring structure. D4 is typically a  clear, colorless, and odorless volatile silicone fluid. Its unique blend of low viscosity, high volatility, excellent spreadability, and a non-greasy feel makes it a foundational ingredient in numerous applications, particularly within the personal care sector, as well as a crucial building block in silicone chemistry.

Basic Information of Octamethylcyclotetrasiloxane

CAS No.:	556-67-2
EC No.:	209-136-7
Linear Formula:	[(CH₃)₂SiO]₄
Molecular Weight:	296.62
Appearance:	Transparent Liquid
Melting Point:	17-18 °C (lit.)
Boiling point:	175-176 °C (lit.)
Density:	0.956 g/mL at 25 °C (lit.)
Volatility:	Highly volatile, evaporates cleanly without leaving residue.
Feel:	Imparts a smooth, soft, and non-greasy feel.
Stability:	Chemically inert and thermally stable.
RIDADR:	UN 1993 3/PG 3
Chemical Structure:

Applications of Octamethylcyclotetrasiloxane (D4)

Octamethylcyclotetrasiloxane (D4) is a versatile ingredient, widely employed across various sectors due to its unique physical and chemical properties:

• Personal Care and Cosmetics:

• Deodorants and Antiperspirants: Acts as a carrier for active ingredients, providing a smooth, dry application and feel.

• Hair Care: Used in conditioners, styling products, and serums to impart shine, enhance manageability, detangle hair, and reduce drying time without residue.

• Skin Care: Found in creams, lotions, sunscreens, and makeup removers for its light, non-greasy texture, aiding in spreadability and leaving a silky feel on the skin.

• Makeup: Improves spread and sensory feel in foundations, mascaras, and other cosmetic formulations.

• Silicone Synthesis:

• A critical monomer for the production of high-molecular-weight linear polydimethylsiloxanes (PDMS) through ring-opening polymerization. These polymers form the basis of various silicone oils, elastomers, and resins.

• Used in the synthesis of specialized silicone polymers with tailored properties.

• Industrial Applications:

• Specialty Solvent: Functions as a volatile carrier or diluent in specific industrial formulations, including coatings and electronics.

• Lubricants: Utilized in specialty lubricants where low viscosity and a non-greasy profile are required.

• Cleaning Products: Component in some dry-cleaning fluids and industrial cleaning agents.

• Consistent Quality: Our stringent quality control processes ensure that every batch of D4 meets the highest industry standards.

Hazards Classification

• GHS Classification: Flammable Liquid (GHS02), Health Hazard (GHS08), Environmental Hazard (GHS09)

• Hazard Statements: Flammable liquid and vapor; suspected of damaging fertility or the unborn child; toxic to aquatic life with long lasting effects.

• UN Number: UN 1993

• Hazard Class: 3 (Flammable Liquids)

• Packing Group: III