Enzymatic synthesis of polymer acrylates and their evaluation as wood coatings

UV-curable acrylates are the base for a large and growing product group within the coatings industry. Traditional chemical catalysis is poorly suited for acrylation reactions since these require low temperatures to avoid polymerization. In this study, immobilized Candida antarctica lipase B has been used to efficiently acrylate four polymers through transesterification of ethyl acrylate, via a solvent-free process using continuous distillation. The four products were based on three polyesters and one polyether, which represent two major classes of acrylates used in coatings today. The performance of the products was estimated with regard to curing rate, hardness, and chemical-resistance. While each product by itself had some weakness, a combination of acrylated polyether and polyester produced an adequate curing rate, good hardness, and excellent chemical-resistance properties.