At TYM, we use silicone in a range of different products, from tubing to gaskets. For example, our Metal Detectable Silicon Sheet has revolutionised the way silicone contamination is detected in the food industry, and our Platinum Cured Silicone Tubing is the superior option for drinks vending machines.
Silicone is so widely used due a variety of useful properties, including flexibility, adhesion, insulation, and low toxicity. However, one of the most important characteristics of silicone is its heat resistance, allowing silicone products to maintain their properties when exposed to both high and low temperatures.
Before going any further, it is important to note that “silicone” is not a single material, but actually refers to a whole category of polymers. These silicones are typically heat-resistant and rubber-like. However, for the sake of simplicity, we can refer to “silicone” as a single material for the rest of this post.
Also note that silicone should not be confused with the chemical element silicon, although silicones do contain silicon atoms.
So, why is silicone heat-resistant? Silicone has a low thermal conductivity, which means that it transfers heat at a low rate compared to other materials. This low thermal conductivity can also be described as high thermal (heat) resistance. In addition to simply resisting heat, silicone also exhibits thermal stability, or the ability to maintain its properties and structure over a wide temperature range.
Fundamentally, this heat resistance is due to the highly stable chemical structure of silicone. More specifically, silicone has a backbone which consists of repeating units of siloxane bonds (alternating silicon and oxygen atoms) that are tightly bound together. It is this highly-stable formation that is partly responsible for the heat-resisting characteristic of silicone. Furthermore, the coiled structure of silicone molecules, combined with low levels of force between molecules, also provides good resistance to cold temperatures. These aspects of chemical structure are also responsible for many of the other properties of silicone.
Due to these properties, silicone products can often operate in conditions ranging from well below freezing to over 200°C. Based on this, in addition to its other properties, it is no surprise that silicone is used for so many different purposes.