Silicone is a non-metallic, inorganic material that is either clear or opaque. It can be hard and brittle or soft and rubber-like, depending on the silicone rubber recipe used. Silicone has excellent resistance to chemical attack, even at elevated temperatures. It is also relatively inert chemically and biologically -- it does not undergo hydrolysis like some plasticizers do, nor does it break down under most common environmental conditions. Silicone rubber is also resistant to degradation under physical conditions such as hot or cold temperatures, solvents, and organic solvents.
Some silicones are used in a highly pure form called trade varnishes as a coating on metal alloys to prevent oxidation. They are also used to manufacture flexible silicone rubber sheets for specialized applications such as shock-absorbers for automobile hoods, which are usually made of synthetic rubbers. Other applications include heat-resistant elastomers for hand and machine gloves, dielectric materials in capacitors and insulating films, industrial gloves, sealing the joints of pipes when building houses, and produce high-temperature insulation tape.
The earliest silicone rubber was made by adding chlorosilanes to polyvinyl chloride rubber. This basic formula is still the most widely used and important type of silicone rubber.
Silicone rubber is manufactured in two different ways: via an emulsion process or via a solution process. The traditional method of manufacturing silicone elastomers through an emulsion process, was not able to produce the higher-molecular weight silicones needed for a variety of applications.
The solution process allows both high-and low-molecular weight silicones to be manufactured. Silicon is a chemical element obtained from various types of silicon dioxide such as sand, using the process of heating or roasting. Silicon is an essential element for plants and animals, and it's found in high quantities in the earth's crust- about three percent over all. It has a number of different uses including in semiconductors, and it's also used to produce polysilicon which can be processed to produce silicon metal that can be made into wires or tubes for use in semiconductor devices.
Silicon is one type of a larger family known as metalloids. The important benchmark industrial grade purity level for silicon metal is 99%. Silicon can exist as a pure metal, silicide, or silicon carbide (a hard ceramic). Other metalloids include boron and germanium. An alternative spelling for silicon is silicium, which is more commonly used in Europe. The origin of the name silicon comes from the Greek word "silicon" which means flint, reflecting the fact that silicon in its natural form is found as crystals in certain types of rocks.
Silicon is an essential element for plants and animals, and it's found in high quantities in the earth's crust- about three percent over all. It has a number of different uses including in semiconductors, and it's also used to produce polysilicon which can be processed to produce silicon metal that can be made into wires or tubes for use in semiconductor devices.
Silicon has been used by humans from manufacturer to microprocessors since it was first created in sandstone in 1824 by Italian chemist Amedeo Avogadro. However, it is toxic to humans if ingested and can cause respiratory distress, among other things. The most well-known work with silicon is the creation of integrated circuits, from which silicon derives its name. In 1811, Humphry Davy was able to isolate silicon by heating a mixture of sand and potassium carbonate (KCO). Silicon was first isolated in its metallic state by Friedrich Wöhler in 1824.