Synthesis of novel vinyl ester from biobased phloroglucinol

Abstract

For the first time a vinyl ester network was synthesized from biobased phloroglucinol. Phloroglucinol is a biobased phenol extracted from phlorotannins found in brown algae such as kelps and rockweeds or sargassacean species. Phloroglucinol has an interesting chemical structure with an aromatic ring and three phenol functions. In this study, phloroglucinol was epoxidized with epichlorohydrin in a first step and then methacrylated with methacrylic acid in a second step. Finally, methacrylated phloroglucinol was copolymerized with styrene by free radical copolymerization. The copolymerization with styrene led to a vinyl ester material. This material was characterized and presents high thermal stability and thermomechanical properties. The glass transition temperature value of the obtained material (165°C) is higher than that of bisphenol A (BPA)-derived vinyl esters (135°C). Most vinyl ester materials are synthesized from BPA, which is a very toxic substance. Therefore, phloroglucinol could interestingly be a possible substitute for BPA in such thermoset networks for composites.