Studies to Improve the Wear Durability of Polytetrafluoroethylene (Teflon) Coatings on Elastomeric Vulcanizates

摘要

Methods for improving the wear durability of polytetrafluoroethylene (TFE) coatings on vulcanized elastomeric substrates have been investigated. A high-temperature flame-sintering technique has been developed which substantially improves the abrasion resistance of the TFE coatings, even in contact with rough surfaces such as 12-oz duck canvas. The flame-sintered TFE coatings exhibited a high order of durability in contact with smooth steel and anodized aluminum surfaces. Nonanodized aluminum surfaces were severely abraded by the TFE coatings. The flame-sintering treatment did not appreciably degrade the physical properties of most of the elastomers studied, nor did it adversely affect the frictional properties of the TFE coatings. Stabilizers utilized in gum neoprene and acrylonitrile elastomers tended to interfere in the adhesion of the TFE coating, but cleaning the surface of the vulcanizate with an aromatic solvent prior to application of the coating improved the adhesion. A thin evaporated reflective aluminum film on the elastomer substrate provided an effective interfacial heat barrier for sintering TFE coatings with infrared heat. Vulcanizates coated only with TFE were burned and charred using this heat source. More work is needed, however, to improve the abrasive resistance of this combination of coatings.