Properties of Silicones

The backbone structure of silicone polymers, also known as polysiloxanes, is devoid of carbon. Although silicon is in the same periodic table group as carbon, its chemistry is substantially different. There are many silanes that are similar to hydrocarbons with Si – Si bonds. These chemicals aren’t very stable, thus they’re useless. Silicones, on the other hand, have a structure that alternates between Si and O. This fundamental structural unit can be found in a variety of rocks and minerals, including ordinary sand.

Several chemical groups such as methyl or the benzene ring can be linked to silicon. Silicones are water-repellent, heat-resistant, and chemically resistant. They’re used in a variety of oils, greases, and rubbery materials. Silicone oils are highly desirable since they do not break down and do not get viscous at high temperatures. Other silicones are found in hydraulic fluids, electrical insulators, and fabrics as a moisture proofing agent.

Properties of silicones

By substituting alternative chemical groups for the methyl groups, properties such as solubility in organic solvents, water repellent, and flexibility can be changed. Silicones containing phenyl groups, for example, are more flexible than those with methyl groups. They’re also more effective lubricants and organic compound solvents.

Heat resistance

Silicone has a low thermal conductivity, which means it doesn’t transmit heat as quickly as other materials. This high thermal (heat) resistance can also be characterised as low thermal conductivity. Silicone has thermal stability, or the ability to keep its properties and structure throughout a large temperature range, in addition to just resisting heat.

This heat resistance is primarily owing to silicone’s chemical structure, which is extremely stable. Silicone has a backbone made up of firmly bonded repeating units of siloxane bonds (alternating silicon and oxygen atoms). The heat-resisting property of silicone is due in part to its highly stable structure.

In addition, the coiled shape of silicone molecules, along with low amounts of tension between molecules, provides excellent cold temperature tolerance. Many of the additional qualities of silicone are due to these features of the chemical structure.

Temperature range

Silicone is quite popular because of its resistance to temperature fluctuations. The working temperature of most silicone ranges from -60⁰ C to +230⁰C. The length of time it is subjected to such temperatures, on the other hand, will determine its capacity to maintain integrity inside the application.

There are particular varieties of silicone that can withstand a wider temperature range. Temperatures as high as +300⁰Ccan be tolerated by high-temperature silicone rubber.

Uses of silicones

Silicones are categorised in a variety of ways depending on how they are prepared.

• Silicone fluids 

• Silicone gels 

• Silicone liquids

• Silicone elastomers (rubbers) 

• Silicone resins 

Their physical shape and applications are determined not only by the polymer’s structure, which can be a short or long chain molecule, a three-dimensional network, or a crosslinked silicate-like species, but also by the organic groups bonded to the Si – O framework.

Solubility of silicones

Silicone fluid is extremely soluble in both hydrocarbon and chlorinated hydrocarbon solvents such as toluene, xylene, ligroin, and mineral spirits. It is insoluble in ethanol, methanol, and water, though.

Conclusion

“Silicoketone,” which he abbreviated to silicone, was the technical word for these compounds.

Silicone is a polymer made up of repeating silicon and oxygen strands. Inert synthetic compounds like siloxanes, which are made up of silicon and oxygen atoms with carbon and hydrogen, are used to make these polymers.

Silicone is also known as polysiloxane.