PDMS, or Polydimethylsiloxane, is a type of silicone fluid that consists of repeating units of -Si(CH₃)₂O-. It is also known as dimethyl silicone fluid. 

PDMS has a linear or branched polymer structure where silicon atoms are alternately bonded to oxygen atoms and methyl (-CH₃) groups. PDMS is characterized by its high thermal stability, low surface tension, excellent lubricating properties, and resistance to oxidation and chemicals. It typically exists as a clear, viscous liquid at room temperature.

Applications:

Cosmetics and Personal Care: PDMS is used in skincare products, hair conditioners, and antiperspirants due to its smooth feel and water repellency.

Industrial Lubricants: It serves as a lubricant in machinery and equipment where high and low-temperature stability are crucial.

Medical and Healthcare: PDMS is used in medical devices such as catheters and implants because of its biocompatibility and inertness.

Electronics: It is used in electronic applications as a heat transfer fluid and dielectric coolant.

Construction: PDMS is used in sealants, adhesives, and coatings for its water resistance and durability.

Silicone Fluid Grades: PDMS comes in various viscosity grades, ranging from low-viscosity fluids (similar to water) to high-viscosity oils (similar to honey), catering to different application needs.

Overall, PDMS is a versatile silicone fluid with a wide range of industrial, commercial, and consumer applications, owing to its unique combination of properties and ease of processing.