*Offer valid 12/26/16-12/30/16 while supplies last at participating Hallmark Gold Crown stores in the U.S.A. and at Hallmark.com. Discount will be taken on equal or lesser-valued item. Not valid on past purchases. Hallmark.com orders require U.S. billing and shipping addresses.
Depending on the application and the designof the seal, the material used may be nitrile, polyacrylate, fluoroelastomer(Viton), silicone, nylon or TeflonÂ¨. Nitrile is one of theleast expensive materials, and has been used for many years inumbrella or deflector type seals for older pushrod engines.
The performance of fluoroelastomers in aggressive chemicals depends on the nature of the base polymer and the compounding ingredients used for molding the final products (e.g. O-rings). This performance can vary significantly when end-users purchase Viton polymer containing rubber goods from different sources.here are four families of viton polymers: 1  A (Dipolymers of VF2/HFP): General purpose sealing. 2  Automotive, Aerospace fuels & lubricants. 3  Nominal polymer fluorine content: 66%. 4  B (Terpolymers of VF2/HFP/TFE): Chemical Process plant, Power Utility Seals & Gaskets.