Adhesion improvement of tire cord induced by gas plasma

Abstract

The adhesion of poly(ethylene terephthalate) (PET) to rubber in tire composites was significantly improved by exposure of the PET to “low-temperature” gas plasmas. Rubber composites built using a single-dip resorcinol–formaldehyde–latex (RFL) adhesive and plasma-treated PET reinforcement were studied. The effects of treatment conditions on this adhesion improvement were examined. The improvement was insensitive to nature of the gas, exposure time, power level, and pressure within the operating limits of the plasma generator. Fiber finish on filaments being treated was detrimental to the adhesion improvement; however, an overcoating of treated filaments with finish was not detrimental. The effects of tire building operations on this adhesion improvement of treated PET were examined. The improvement was found over a wide range of adhesives, adhesive-curing conditions, rubber compositions, and bonding testing conditions.