Лако-красочные материалы — производство

Contact Adhesives. Nowadays, rubber solutions based on natural rubber or sty­rene-butadiene rubber, optionally in conjunction with regenerate and depolymerized rubber, are used for large-area bonding where adhesion does not have to meet stringent requirements, as is the case, for example, with the lining of vessels, containers, etc. with rubber.

Today, multipurpose adhesives based on polychloroprene rubber generally are used as adhesives for rubber articles.

Reactive Adhesives. Epoxy and polyurethane adhesives are suitable for bonding polar elastomers, such as nitrile rubber and chloroprene rubber. However, epoxy adhesives form a relatively rigid bond so that they are suitable only for bonding to rigid substrates. In contrast, polyurethane adhesives form elastic bonds and therefore are used for rubber-to-rubber and rubber-to-leather bonding, for example, in the manufacture of profiles and in the shoe industry.

Polyurethane adhesives also are suitable for bonding nonpolar elastomers, for example, natural rubber, styrene — butadiene rubber, or ethylene-propylene terpol- ymers, after chemical pretreatment of the surface.

Polymerization adhesives based on a-cyanoacrylates (see p. 30) are suitable for special bonds involving rubber, because they enable bonds of high strength to be obtained quickly and easily. Medium-viscosity types are preferred for rubber-to-rubber bonds by virtue of the minimal hardening of the joint. In the rubber industry, for example, the adhesives are used for bonding profiles to one another and also for repair work.

Because of the increasingly stringent requirements that rubber articles have had to satisfy over the past 20 years, the bonding process is preferred in the manufacture of rubber-metal composites.