Silicone is a unique synthetic rubber that is known for its large operating temperature range as well as its FDA approved sheets. Silicone sheet rubber is an inorganic polymer that is made up of a silicone-to-oxygen bond rather than the common carbon-to-carbon bond found in most elastomers.High temperature silicone material is able to withstand temperatures without melting or becoming deformed while also having the ability to remain flexible in low temperatures. In addition, color silicone sheets, such as black silicone rubber, are available to help differentiate various industrial rubber parts from other parts which can help promote a safe and efficient industrial workplace. Furthermore, silicone sheet rubber is extremely resilient against damaging outdoor environmental factors such as UV rays, ozone, and oxygen allowing them to provide long-lasting and reliable applications.

Is Silicone a Rubber?

Silicone is a resilient synthetic rubber material that is made up of silicon, carbon, hydrogen, and oxygen. More specifically, “Silicone rubber (SIR) is an elastomer composed of silicone containing silicon, carbon, hydrogen, and oxygen, in the form of a polymer” (sciencedirect.com). Silicone sheet rubber, also known as polysiloxane, is considered an inorganic polymer due to its unique silicon-to-oxygen polymer backbone structure. For instance, “A polymer is called inorganic if its backbone is either made up exclusively of non-carbon elements, or, when carbon is present, if it is not bonded to hydrogen or organic side groups” (polymerdatabase.com). Silicone sheet rubber is also a widely used elastomeric material that is best known for being able to remain flexible at low temperatures while also being able to withstand high temperatures thanks to its unique silicon-to-oxygen bonded backbone structure. This high temperature silicone material will also remain solid and resist melting when coming into contact with temperatures as high as +500 degrees Fahrenheit. Additionally, the term “elastomer” is essentially a fancy word for “rubber”; an elastomer is “any rubbery material composed of long chainlike molecules, or polymers, that are capable of recovering their original shape after being stretched out” (Britannica.com). Due to its silicon-to-oxygen polymer backbone structure, silicone sheet rubber is able to retain its flexibility over a wide range of extreme temperatures, both high and low.

Most polymer backbones, including synthetic polymer backbones, consist of a carbon-based backbone structure “of at least four carbon atoms with a double-single-double bond reactive core (C=C-C=C)” (chem.libretexts.org). Contrastingly, “inorganic repeat units in polymer backbones such as silicon-oxygen or phosphorous-nitrogen are typically much more thermo-oxidatively stable than their organic counterparts, and thus, possess superior heat – and fire – resistance” (polymerdatabase.com). Silicone sheet rubber is a highly resilient and long-lasting material, even in the most abrasive environments. For instance, “Silicone rubbers or elastomers are a range of heat stable elastic silicone materials used for electrical insulation as sheet, tape, wire, and cable coverings, extruded sleevings and mouldings, unsupported, but more extensively as coated glass-fibre cloths, tapes and braided glass sleevings” (sciencedirect.com). In addition, silicone sheet rubber, like most synthetic elastomers, have excellent environmental resistance properties. Oftentimes, elastomers are susceptible to damage caused by ozone on the bonds holding the polymer’s backbone together – causing “ozone cracks”. For example, “The backbone of this polymer is extremely resistant to skeletal oxidative cleavage at elevated temperatures because there is no oxidative driving force since the bonds to each silicon are already linked to oxygen…[Silicone] also possesses excellent low temperature flexibility, as well as outstanding resistance to weathering and many chemicals” (polymerdatabase.com). Silicone sheet rubber is a flexible synthetic rubber material that is able to retain its flexibility in low temperatures while also remaining a resilient and intact material in abrasively high temperatures.

• (a) Is Silicone More Durable than Rubber?

  Silicone is more durable than most rubber products due to its unique properties that are provided by the silicon-to-oxygen bond found in its polymer backbone structure. Although natural rubbers are highly resistant to physical damage caused by impacts and abrasions, it is susceptible to degradation when exposed to UV rays, ozone, chemicals, and extreme temperatures. For instance, “Crude rubber possessed the valuable properties of elasticity, plasticity, strength, durability, electrical nonconductivity, and resistance to water; however, products made from it hardened in winter, softened and became sticky in summer, were attacked by solvents, and smelled bad” (chemistryexplained.com). Chemical resistant silicone, contrastingly, is highly resistant to degradation caused by chemicals as well as environmental factors and extreme temperatures. Case in point, “As compared to organic rubber, silicone rubber has Si-O bond in its structure, and hence, it has better: heat resistance, chemical stability, electrical insulation, abrasion resistance, and weatherability as well as ozone resistance” (omnexus.specialchem.com). Due to its temperature stability, silicone sheet rubber will not become brittle when exposed to low temperatures as low as -103 degrees Fahrenheit and will remain flexible. In addition, high temperature silicone is able to withstand and remain a solid material even when exposed to temperatures of up to 500 degrees Fahrenheit. Natural rubber is highly susceptible to embrittlement at low temperatures and melting at high temperatures. For example, “Most elastomers will undergo significant changes over time when exposed to heat, light, or oxygen (ozone)…The aging of a rubber due to oxidation and heat is greatly accelerated by stress, and exposure to other reactive gases like ozone. Besides embrittlement (chain hardening) or softening (chain scission) other visible changes such as cracking, charring, and color fading is observed” (polymerdatabase.com). Due to the silicon-oxygen bonds that make up the polymer backbone of silicone sheet rubber makes it more durable than natural rubbers.

  (b) Does Silicone Come in Black?

  Silicone comes in black as well as a variety of other color silicone sheets including red, gray, blue, brown, white, and even translucent. Black silicone rubber is often used for industrial purposes due to its bold and professional aesthetic. Black silicone rubber is able to resist highly abrasive temperatures, impacts, and chemical solvents making it an ideal material for industrial use. Premium grade black silicone rubber sheets are able to withstand temperatures of up to +500 degrees Fahrenheit; however, other black silicone rubber sheets, such as commercial grade, will only have high temperature resistance up to 450 degrees Fahrenheit. The variety of difference colors does not change the properties of the silicone sheet rubber and they are still capable of being exposed to abrasive temperatures, chemicals, UV rays, ozone, and oxygen. The different colors allow industrial parts to be easily identified for a specific application. For instance, grabbing the wrong rubber part for an industrial application can not only cost you extra money in repairs, but it can also create an unsafe work environment, depending on the application. The color white is commonly used in the food and medical field due to its soft and light aesthetics. Silicone sheet rubber come in a wide variety of color silicone sheets to help differentiate between different parts for different applications.

At What Temperature Can Silicone be Applied?

Silicone can be applied over a wide range of temperatures ranging from as low as -103 degrees Fahrenheit to as high as +500 degrees Fahrenheit. Silicone sheet rubber has a unique silicon-to-oxygen bonded backbone structure allows it to remain a durable elastomer even in extreme temperatures. High temperature silicone is a unique inorganic material that is able to keep its shape when exposed to abrasive heat up to +500 degrees Fahrenheit instead of melting like natural rubber. However, it is important to remember that beyond the 500-degree Fahrenheit temperature range, silicone sheet rubber will be susceptible to becoming hard and cracking. Case in point, “The embrittlement of silicone rubber is due to an increase in the amount of chain cross-linking. When silicone rubber is exposed to air at temperatures about 250 °C (482 °F) oxidative cross-linking reactions occur at methyl side groups along the main chain. These cross-links make the rubber significantly less ductile” (Wikipedia.org). Embrittlement refers to the hardening or softening of material that makes it susceptible to cracking. For most elastomers, low temperatures cause the material to harden making it easy to crack or break with the slightest bend. Silicone sheet rubber, although susceptible to embrittlement at temperatures beyond +500 degrees Fahrenheit, is able to remain flexible at low temperatures without stiffening or becoming brittle.

Silicone sheet rubber is popularly used for applications involving abrasive high and low temperatures. High temperature silicone is able to withstand such abrasive temperatures due to its unique silicon-to-oxygen backbone structure which also allows it to remain flexible at high and low temperatures without chances of embrittlement or melting. Color silicone sheets are also available to help create safe industrial settings by allowing brighter colors to stand out and allowing for color matching parts to their respective applications. Black silicone rubber is often used for a sleek and industrial aesthetic whereas white silicone is generally seen being used in pharmaceutical or food processing applications. Additionally, chemical resistant silicone is also able to stand up well against abrasive chemical solvents. Overall, silicone sheet rubber is a highly durable material that is most often used in industrial settings as well as in applications made for human consumption.