Cyclosiloxanes are a class of silicone material. They are volatile and often used as a solvent. The three main commercial varies are octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6). They evaporate and degrade in air under sunlight.[1]
Octamethylcyclotetrasiloxane (D4)[edit]
The octamethylcyclotetrasiloxane silicone liquid has no odor and consists of four repeating units of silicon (Si) and oxygen (O) atoms in a closed loop giving it a circular structure. Each silicon atom has two methyl groups attached (CH3).
Decamethylcyclopentasiloxane (D5)[edit]
Decamethylcyclopentasiloxane silicone liquid has no odor and consists of five repeating units of silicon (Si) and oxygen (O) atoms in a closed loop giving it a circular structure. Each silicon atom has two methyl groups attached (CH3). Typically it is used as an ingredient in antiperspirant, skin cream, sun protection lotion and make-up. With a low surface tension of 18 mN/m this material has good spreading properties.[2]
Dodecamethylcyclohexasiloxane (D6)[edit]
The dodecamethylcyclohexasiloxane silicone liquid has no odor and consists of six repeating units of silicon (Si) and oxygen (O) atoms in a closed loop giving it a circular structure. Each silicon atom has two methyl groups attached (CH3).
References[edit]
- ^ "Cyclosiloxanes Information Center - What are Cyclosiloxanes?". www.cyclosiloxanes.org.
- ^ "XIAMETER™ PMX-0245 Cyclopentasiloxane Technical Data Sheet" (PDF). Dow.