This is a new type of highly corrosion-resistant polyester resin newly developed in the late 1960s. It is usually an epoxy resin and ethylenically unsaturated monobasic acid and adduct.
Vinyl ester unsaturated polyester resin is also called vinyl ester resin, acrylic polyester resin or epoxy acrylic polyester resin. In terms of molecular structure, the macromolecule of vinyl ester polyester contains both the main chain structure of the epoxy resin molecule and the polyester structure with unsaturated double bonds. Therefore, this type of resin has both good adhesion and mechanical strength of epoxy resin, and good curing properties of unsaturated polyester resin. Especially outstanding is that in terms of corrosion resistance, it is not only much better than ordinary unsaturated polyester resins and epoxy resins, but also better than phenol A-type unsaturated polyester resins in certain media. This is because vinyl ester polyesters are different from ordinary unsaturated polyesters whose main bonds contain cyclic ester groups. The former contains only terminal ester groups in the molecule, and the concentration of ester groups (means the average number of ester groups per 100g of unsaturated polyester resin Moles) is lower. The ester group is a weak structure in terms of corrosion resistance, and the less the ester group, the higher the corrosion resistance. In addition, its ester group has a methyl group on the adjacent carbon atom, this methyl group can play a role in protecting the ester group.
In the presence of a catalyst, vinyl ester resins are prepared by the addition reaction of various unsaturated monocarboxylic acids and various epoxy resins, and the grades of vinyl resins with different raw materials are also different.