Silicone rubber is an elastomer (rubber-like material) composed of silicone—itself a polymer—containing silicon together with carbon, hydrogen, and oxygen. Silicone rubbers are widely used in industry, and there are multiple formulations. Silicone rubbers are often one- or two-part polymers, and may contain fillers to improve properties or reduce cost. Silicone rubber is generally non-reactive, stable, and resistant to extreme environments and temperatures from -55 °C to +300 °C while still maintaining its useful properties. Due to these properties and its ease of manufacturing and shaping, silicone rubber can be found in a wide variety of products, including: automotive applications; cooking, baking, and food storage products; apparel such as undergarments, sportswear, and footwear; electronics; medical devices and implants; and in home repair and hardware with products such as silicone sealants.
Silicone rubber offers good resistance to extreme temperatures, being able to operate normally from −100 to 300 °C (−148 to 572 °F). Some properties such as elongation, creep, cyclic flexing, tear strength, compression set, dielectric strength (at high voltage), thermal conductivity, fire resistance and in some cases tensile strength can be—at extreme temperatures—far superior to organic rubbers in general, although a few of these properties are still lower than for some specialty materials. Silicone rubber is a material of choice in industry when retention of initial shape and mechanical strength are desired under heavy thermal stress or sub-zero temperatures. Organic rubber has a carbon-to-carbon backbone which can leave it susceptible to ozone, UV, heat and other ageing factors that silicone rubber can withstand well. This makes silicone rubber one of the elastomers of choice in many extreme environments.
Silicone rubber is highly inert and does not react with most chemicals. Due to its inertness, it is used in many medical applications including medical implants. It is biocompatible, hypoallergenic and non-allergenic, which makes it suitable for baby care products, and food contact in general. Silicone rubber is a reliable solution (as opposed to rubber and TPE) for migration or interaction problems between the main active ingredients. Its chemical stability prevents it from affecting any substrate it is in contact with (skin, water, blood, active ingredients, etc.).