MilliporeSigma

Silicone Materials

Representative chemical structure of polysiloxane, commonly known as silicone and silicone oil

SILICONES

Silicones, also known as polysiloxanes, are synthetic polymers with a silicon-oxygen backbone like that in silicon dioxide but containing additional organic groups. Unlike homologous carbon-based polymers, these compounds show a unique combination of physical and chemical properties due to the exceptional physicochemical properties of the siloxane (-Si-O-) bond. Silicone-containing copolymers and silicone-modified networks have extremely high backbone flexibility and very low glass transition temperatures (Tg), around −120 °C. They also demonstrate good thermal and oxidative stability, high gas permeability, excellent dielectric properties, biocompatibility, and minimal surface tension.


Products



CLASSIFICATION OF SILICONES

Our silicone (polysiloxane) silicone polymers demonstrate a variety of silicone material properties and can be categorized as fluids, elastomers, or resins. Polymers of moderate molecular weight are classified as fluids, while slightly cross-linked polymers with high molecular weight are elastomeric. Low molecular weight resins contain functional groups, usually hydroxyl, alkoxy, or chloro groups, that undergo hydrolysis and/or condensation to form highly cross-linked structures.

Common silicone material science applications of our basic products include:

  • Silicone elastomers, such as polydimethylsiloxane (PDMS), for patterned stamps in soft lithography and nano-pattering applications
  • Dielectric materials for electrostatic actuators and dielectric energy harvesters
  • Encapsulation and packaging materials for electronic devices
  • Surface property modifying reagents for microfluidic applications

SILICONE COPOLYMERS AND HOMOPOLYMERS

Silicone co- and homopolymers form a hydrophobic surface with low water uptake and are primarily used in the preparation of lubricants, foams, and polymeric adhesives.

Silicones in our catalog have:

  • Non-reactive substitutes that tune the mechanical and thermal-mechanical properties (such as glass transition temperature)
  • Reactive substitutes and terminal groups to allow chemical modification (such as crosslinking)
  • Varying molecular weights and viscosity levels.

SILICONE OILS

Our catalog includes silicone oils (or silicone fluids) which are any liquid polymerized siloxane having organic side chains. They are more thermodynamically stable than other siloxanes due to a highly polarized Si‐O‐Si bond with a large bond energy. Silicon fluids exhibit greater structural flexibility, permeability, and lubricity due to freely rotating methyl groups as well as weak intermolecular attractive forces. Furthermore, they have excellent wetting and film-forming properties due to lower surface tension and are odorless, non‐toxic, water-repellent, chemical-resistant, and UV-resistant.

We offer a wide range of silicone oils with various degrees of viscosity, spanning from 5 c St (or 5 mPa∙s) to 100,000 c St (or 100,000 mPa∙s) at 25 ˚C. Our silicone oils can be used as heating and cooling fluids in thermal management. When used in water/oil systems, our siloxanes generate stable emulsions of microdroplets which are widely used in DNA and blood analysis, chemical reactions, drug discovery, ink formulations, cosmetics, textiles, and home care products.