Contact with Plastic Surfaces

With the increasing use of plastic parts in many areas of modern manufacturing, it has become mandatory for O-rings to effectively seal against an ever-widening variety of plastic as well as metal surfaces.

The problem encountered with O-ring contact with plastics is the adverse effect of compound ingredients, such as plasticizers, inducing surface cracking ("crazing") in plastics. This crazing may eventually lead to physical weakness and/or failure of the plastic structure.

Best Choice(s)

EP, Fluorocarbon and Silicones

Special formulated Nitriles can be used. Normal Nitriles use the same plasticizers that soften most plastics. It is very important to identify when a seal material is going to be used with plastics.