Recent Advances in the Enzymatic Synthesis of Polyester

Abstract

Polyester is a kind of polymer composed of ester bond-linked polybasic acids and polyol. This type of polymer has a wide range of applications in various industries, such as automotive, furniture, coatings, packaging, and biomedical. The traditional process of synthesizing polyester mainly uses metal catalyst polymerization under high-temperature. This condition may have problems with metal residue and undesired side reactions. As an alternative, enzyme-catalyzed polymerization is evolving rapidly due to the metal-free residue, satisfactory biocompatibility, and mild reaction conditions. This article presented the reaction modes of enzyme-catalyzed ring-opening polymerization and enzyme-catalyzed polycondensation and their combinations, respectively. In addition, the article also summarized how lipase-catalyzed the polymerization of polyester, which includes (i) the distinctive features of lipase, (ⅱ) the lipase-catalyzed polymerization and its mechanism, and (ⅲ) the lipase stability under organic solvent and high-temperature conditions. In addition, this article also focused on the advantages and disadvantages of enzyme-catalyzed polyester synthesis under different solvent systems, including organic solvent systems, solvent-free systems, and green solvent systems. The challenges of enzyme optimization and process equipment innovation for further industrialization of enzyme-catalyzed polyester synthesis were also discussed in this article.

Lipase-catalyzed solvent-free synthesis of monoglycerides from biodiesel-derived crude glycerol: Optimized using response surface methodology

“…Enzyme-substrate interaction is known to be more active at higher temperatures, leading to an increase in reaction rate [ 57 ]. However, beyond a certain temperature, protein thermal denaturation occurs, leading to a sharp decline in reaction rate [ 58 ]. Novozym 435, which is capable of catalyzing at 110 °C [ 49 ], does not undergo denaturation at 50–70 °C and significantly enhances the yield of monoglyceride.…”

Recyclable and (Bio)degradable Polyesters in a Circular Plastics Economy

“…566−568 The reactions catalyzed by lipases proceed through the formation of an intermediate compound known as an acyl−enzyme. 569 Uyama et al elucidated the mechanism of lipase-catalyzed ROP. First, the lactone substrate binds to the lipase, which promotes ring opening and the formation of an active acyl− enzyme intermediate, also referred to as the enzyme-activated monomer (EM).…”

“…The ROP of lactones mediated by lipases follows an activated monomer mechanism. The active site of a lipase consists of a catalytic triad made up of serine, histidine, and aspartate, all of which are electronically stabilized. − The reactions catalyzed by lipases proceed through the formation of an intermediate compound known as an acyl–enzyme . Uyama et al elucidated the mechanism of lipase-catalyzed ROP.…”

Enzymes in Poly(Butylene-Succinate) Industry: An Overview on Synthesis Routes and Post-Processing Strategies

“…An eROP of lactones with different numbers of carbon atoms performed by Wang et al [25] led to polyesters with straight or branched chains with excellent results when Novozym 435 was employed as a biocatalyst. In the same study, polycondensation of different hydroxyacids, diols,diacids, or diols and diacid derivatives was also evaluated, including the possibility of synthesizing PBS catalyzed by Novozym 435 [25].…”