Silicone rubber is used for seals, gaskets and extrusions because it remains flexible in both hot and cold conditions. But in high-temperature applications, the critical question is not just can it cope today but how long will it last over prolonged use? Our test data shows that a general-purpose grade can harden by more than 15 Shore A points after just 28 days at 200°C, while a high-temperature grade under the same conditions remains almost unchanged. This process is known as thermal ageing of silicone rubber and it’s the hidden factor that determines service life in high-temperature applications.
For purchasing managers, design engineers and production teams, this is a practical concern. Premature hardening leads to seals that leak, gaskets that crack and unplanned downtime in general. This article explains what thermal ageing is, how it affects silicone rubber and how to specify the right grade for longer performance.
