ASEPCO Parylene Diaphragms: Introducing Silicone Plus and EPDM Plus

photo of diaphragms

Welcome to our new parylene-surfaced silicone and EPDM diaphragms.

You now have a wider choice of elastomeric sealing material. Parylene is vaporized and then vacuum-deposited to form a uniform, impermeable conformal surface coating.

ASEPCO combines the inertness of Teflon and the sealing performance of rubber in our diaphragms.

Advantages over Teflon:

  • Flexes with the rubber—no cold flow
  • Because it is only a surface on an elastomer, you get true sealing
  • Increases diaphragm life (double the life of our standard silicone and EPDM)
  • Increases chemical resistance—parylene is inert
  • Proven biological safety—parylene is a well-known coating for pacemakers

For over 30 years parylene has been used in medical device applications to cover implants like pacemakers and shunts.
Parylene, like Teflon, is hydrophobic and highly resistant to chemical attack. Parylene is a conformal coating that covers all surfaces of a part equally. In addition to the benefits listed above, parylene also offers these benefits:

  • USP Class VI certified
  • Continuous pinhole free in thickness down to 500 angstroms
  • Insoluble in organic solvents @ <150°C
  • Unaffected by most acids and alkalis
  • Low moisture permeability
  • Dry film lubricity approaching that of PTFE
  • Thermal mechanically stable between -200°C and 150°C

Parylene has chemical resistance similar to Teflon. It resists attack and is insoluble in all organic solvents up to 150°C and is resistant to permeation by most solvents with the exception of aromatic hydrocarbons.

Since parylene coating is a high molecular weight, linear, crystalline polymer having an all carbon backbone without any oxygen, nitrogen, or sulfur atom links in the backbone it is hydrophobic. This carbon backbone, coupled with its substantial crystallinity, makes parylene quite stable and highly resistant to chemical attack.

Other technical data on request.