Adhesive Bonds Metal to TPEs Without Primer
TPEs are increasingly used to replace thermoset rubbers. They offer a number of advantages: they are highly flexible, can be combined with other thermoset materials, and they can be processed using standard extruding and injecting molding equipment. However, manufacturers who choose to incorporate TPEs into their products face several engineering challenges. Products made from TPEs are very difficult to bond. In order to ensure good adhesion, TPEs must either undergo special surface treatment or be coated with a primer. Finally, most of the commonly recommended adhesives contain volatile and toxic solvents.
The ACA 30-101, 102, and 103 often eliminate the need for primers and surface treatments altogether, thus substantially reducing the cost of using TPEs. This family of adhesives is designed to cover the entire spectrum of TPE grades from soft to very hard. They provide excellent adhesion, with peel values of up to and exceeding 25 lbs. per linear inch (including substrate tear). Typically, the adhesive is coated to the metal substrate and is processed using standard injection molding or extrusion equipment. Because they are water based, they also simplify EPA and OSHA compliance.