A novel approach of promoting adhesion of reinforcing cord to elastomers by plasma polymerization

Adhesion of cords to elastomers is crucial for many elastomeric products, such as tires and V-belts. The best adhesion system so far is based on a combination of resorcinol, formaldehyde, and a latex (RFL). However, this cord treatment has serious disadvantages in terms of processing and toxicity. A promising alternative is a plasma treatment of the cords prior to be embedded in the elastomer. For rayon cords, a plasma polymerization of sulfur-containing precursors results in adhesion levels close to RFL treatment. However, for polyethylene terephthalate (PET) cords, this treatment is not satisfactory. For this type of cords, a water-plasma activation followed by a silane dip is more promising, as 72% of the adhesion level of RFL treatment could be achieved. For rayon, an even higher adhesion level was realized.