Vinyl ester resins are thermosetting resins that consist of a styrene monomer and the addition products of epoxy resins and methacrylic acid. As a result, they are sometimes referred to as “epoxy vinyl esters”. They are somewhere between epoxies and polyester in performance properties and price. Vinyl esters cure rapidly at room temperature, such as a polyester, but exhibit adhesion and chemical resistance properties that are more representative of an epoxy.
RESULTING PROPERTIES
Because of their excellent durability and mechanical properties, vinyl esters are often the prime candidates to be considered for bonding composites in transportation or infrastructure products. They are often used to bond to composites (i.e., sheet molding compounds, bulk molding compounds, fiberglass reinforced plastic) that are made from a polyester or vinyl ester matrix.
The primary components are the resin, monomer, and curing system (catalyst and promoter, if room temperature cured). The activator is used to start the curing at room temperature. A typical formulation for a low viscosity vinyl ester adhesive resin is provided in the table above.
