New vinyl ester resins based on rosin for coating applications

Vinyl ester resins based on rosin were prepared from rosin adducts using rosin acid as diene and maleic anhydride (MA) or acrylic acid (AA) as dienophile. The produced adducts, maleopimaric (MPA) and acrylopimaric (APA), were used to prepare vinyl ester resins. MPA and APA were reacted with EG followed by reaction with epichlorohydrine in the presence of NaOH as a catalyst to produce epoxy resins. The terminal epoxy groups were reacted with acrylic and methacrylic acid in the presence of triphenyl phosphite as a catalyst to produce divinyl ester resins. The chemical structures of the resulting vinyl ester resins were confirmed by 1H NMR analysis. The curing exotherm vinyl ester resins and styrene was evaluated at temperatures from 35 to 55 °C using free radical initiator and accelerator. The curing behaviors of cured VE resins with styrene were evaluated by DSC measurements. The prepared VE curable resins were evaluated in the field of steel coating by measuring their mechanical properties and chemical resistance.