Temperature and Sealing with TPEs

Some life science applications may require that thermoplastic elastomer (TPE) fluid seals go through thermal cycling for a fixed period. When choosing a TPE for an application, it is important to consider the operating temperature of the material in regard to the application. If TPEs are subjected to temperatures outside their service temperature range (as defined by material manufacturers), they may undergo changes that will affect sealing performance.

• High temperature: At elevated temperatures, TPEs could initially become softer which could affect the fluid seal. If the exposure is short term, the hardness could return to its original state when cooled down. Depending on the material, there are critical temperatures and length of exposure that would permanently change the TPE’s chemical composition. Effects could include inflation, compression set, and hardening. There are medical grade TPEs known to endure the thermocycling of PCR, temperature reaching above 90°C (194°F) or higher (up to around 130°C [around 270°F] for autoclave).
• Low temperature: If temperatures are lower than the material service range, TPEs may harden but will mostly revert to their original characteristics when restored to room temperature. This effect should be considered if the fluid seal must remain intact during cryogenic storage.

For over 20 years, Enplas Life Tech has worked with industry leading clients to solve challenging TPE manufacturing problems, resulting in robust prototypes and industrial-scale manufacturing of the final product. With dedication to meticulous design review and engineering, tool building, injection molding, and assembly, Enplas Life Tech will help you speed up product development and accurately manufacture your fluid-sealing interface.