Ethylene-Propylene Diene Monomer (EPDM) rubber has been used extensively in automotive, wire and cable, roof membrane, and thermoplastic vulcanite (TPV) applications due to the ease of processing imparted by the polymer’s unique structure.1,2 A crosslinking process is usually required to achieve the desired chemical and physical properties, and is accomplished through the incorporation of sulfur or peroxide, and the application of heat and pressure to activate the crosslinking agents and accelerators. However, in some cases, it can be difficult or unfavorable to apply heat to initiate crosslinking, and a low-temperature reaction is preferred.
Coatings, adhesives and sealants are one such application in that the rubber is applied in a thin film over a large area, making it difficult to heat the elastomer for curing. EPDM has excellent water, vapor, chemical and electrical barrier properties that greatly improve on elastomeric acrylic, polyurethane and silicone coatings currently available. These properties make EPDM ideally suited for roof coatings and anti-corrosion coatings, especially in low-temperature or high-humidity environments. However, an ideal combination of proper application viscosity, room temperature crosslinking and sufficient working time must be achieved for practical utility.