Polyesters by lipase‐catalyzed polycondensation of unsaturated and epoxidized long‐chain α,ω‐dicarboxylic acid methyl esters with diols

Long‐chain, symmetrically unsaturated α,ω‐dicarboxylic acid methyl esters (C18, C20, C26) were obtained by the catalytic metathetical condensation of 9‐decenoic, 10‐undecenoic, and 13‐tetradecenoic acid methyl esters, respectively, with the homogeneous Grubbs catalyst bis(tricyclohexyl phosphine) benzylidene ruthenium dichloride dissolved in methylene chloride. The dicarboxylic acid esters were epoxidized chemoenzymatically with H2O2/methyl acetate with Novozym 435®, an immobilized lipase B from Candida antarctica. Polyesters from symmetrically unsaturated or epoxidized α,ω‐dicarboxylic acid methyl esters with 1,3‐propanediol or 1,4‐butanediol, respectively, were achieved by enzymatic polycondensation with the same biocatalyst applied. With 1,3‐propanediol as a substrate, the linear unsaturated and epoxidized polyesters had molecular weights of 1950–3300 g/mol and melting points of 47–75 °C, whereas with 1,4‐butanediol as a substrate, the resulting polyesters showed higher molecular weights, 7900–11,600 g/mol, with similar melting points of 55–74 °C.