Ferulic Acid as Building Block for the Lipase-Catalyzed Synthesis of Biobased Aromatic Polyesters

• Published in: Polymers
• Main Authors: Alfred Bazin, Luc Avérous, Eric Pollet
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: Candida antarctica lipase B; ferulic acid; semi-aromatic polyesters; biobased; enzymatic polymerization; Organic chemistry; QD241-441; Antarc*; Antarctica
• Online Access: https://doi.org/10.3390/polym13213693; https://doaj.org/article/796d1b581d334326b120612a5a185ec8

Enzymatic synthesis of aromatic biobased polyesters is a recent and rapidly expanding research field. However, the direct lipase-catalyzed synthesis of polyesters from ferulic acid has not yet been reported. In this work, various ferulic-based monomers were considered for their capability to undergo CALB-catalyzed polymerization. After conversion into diesters of different lengths, the CALB-catalyzed polymerization of these monomers with 1,4-butanediol resulted in short oligomers with a DP n up to 5. Hydrogenation of the double bond resulted in monomers allowing obtaining polyesters of higher molar masses with DP n up to 58 and M w up to 33,100 g·mol −1 . These polyesters presented good thermal resistance up to 350 °C and T g up to 7 °C. Reduction of the ferulic-based diesters into diols allowed preserving the double bond and synthesizing polyesters with a DP n up to 19 and M w up to 15,500 g·mol −1 and higher T g (up to 21 °C). Thus, this study has shown that the monomer hydrogenation strategy proved to be the most promising route to achieve ferulic-based polyester chains of high DP n . This study also demonstrates for the first time that ferulic-based diols allow the synthesis of high T g polyesters. Therefore, this is an important first step toward the synthesis of competitive biobased aromatic polyesters by enzymatic catalysis.