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Why are silicone materials stable at high and low temperatures?

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A periodic table element square for silicon shows atomic number 14, symbol Si, atomic weight range, electron configuration, and name. Icons indicate it is a solid nonmetal with diamond crystal structure and equal relative strength. Labels explain each property. — silicon Chemical properties of the element silicon.

Silicones are remarkably stable at both high and low temperatures primarily due to the unique properties of their molecular structure, which consists of a backbone of alternating silicon and oxygen atoms.12

The stability of these materials is attributed to several key factors:

Strong Chemical Bonds: The presence of strong silicon-oxygen (Si–O) and silicon-carbon (Si–C) bonds provides significant resistance to heat and prevents the material from being easily attacked by oxygen or ozone.312
Molecular Flexibility: Siloxane molecules rotate freely around the Si–O bond, which allows the polymer to remain highly flexible even at low temperatures.12
Low Glass-Transition Temperature: Silicones possess the lowest glass-transition temperature of any polymer, meaning they remain resilient and avoid becoming rigid or glassy at temperatures where other materials would fail.12

Because of these characteristics, silicones maintain their physical properties and viscosity across extreme temperature variations, making them ideal for use as lubricants, seals, and gaskets.312