Silicone resins

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Silicone resins - a type of silicone material that contains oligosiloxanes of general formula: RnSiXmOy, where R is alkyl, usually methyl or phenyl. In contrast, X is a functional group, usually H, OH, Cl or OR. These groups may undergo further condensation to form densely crosslinked, insoluble polysiloxane nets. For the general description of the structure of silicone resins, the following abbreviations are often used:

The most commonly encountered silicone resins are made up of D and T (DT resins) or M and Q resins (MQ resins), but in the industry there are also "mixed" resins (eg MDT, MTQ, QDT). >

Silicone resins form an extensive range of products with a wide variety of useful properties. Their molecular weights are usually between 1000 and 100,000. All of them are liquids at room temperature, provided they are not crosslinked. Such resins, according to the degree of crosslinking, resemble gels in consistency, or are solid elastomers.

Silicone resins are among others. used as: hydrogels used as soft tissue implants (eg breast implants) as silicone gums, as hydraulic oils, paint additives, lubricants, sealing kits and many others.

Silicone resins are produced by the hydrolytic (with water) condensation of various siloxane monomers. The initial resin production technologies were based on the reaction of water glass with chlorosilanes. These substrates are very cheap, but their use makes it more difficult to control the structure of end products. Nowadays, these resins are more often obtained by the reaction of tetraethoxysilane with various disiloxanes and cyclosiloxanes. Bibliography

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