Enzymatic Synthesis of Biobased Polyesters and Polyamides

Abstract

Nowadays, "green" is a hot topic almost everywhere, from retailers to universities to industries; and achieving a green status has become a universal aim. However, polymers are commonly considered not to be "green", being associated with massive energy consumption and severe pollution problems (for example, the "Plastic Soup") as a public stereotype. To achieve green polymers, three elements should be entailed: (1) green raw materials, catalysts and solvents; (2) eco-friendly synthesis processes; and (3) sustainable polymers with a low carbon footprint, for example, (bio)degradable polymers or polymers which can be recycled or disposed with a gentle environmental impact. By utilizing biobased monomers in enzymatic polymerizations, many advantageous green aspects can be fulfilled. For example, biobased monomers and enzyme catalysts are renewable materials that are derived from biomass feedstocks; enzymatic polymerizations are clean and energy saving processes; and no toxic residuals contaminate the final products. Therefore, synthesis of renewable polymers via enzymatic polymerizations of biobased monomers provides an opportunity for achieving green polymers and a future sustainable polymer industry, which will eventually play an essential role for realizing and maintaining a biobased and sustainable society.

High‐Performance Bio‐Based Benzoxazines from Enzymatic Synthesis of Diphenols

“…All these methods based on the use of reactants issued from renewable resources of the abundant biomass represent interesting and promising approaches to decrease the dependence on petro‐based resource consumption. However, to further reduce environmental impacts, greener chemical transformation and eco‐friendly processes should also be considered …”

“…In this context, enzymatic syntheses, which usually takes place in mild conditions with reduced waste treatment requirements due to their higher selectivity and lower byproduct generation, are recently gaining increased consideration from the industrial sector as they represent a potential sustainable alternative to classical organic synthesis to achieve new building blocks and polymer materials by a direct valorization of the biomass . More specifically, lipases appear of particular value for their chemical and thermal stability in solvents, their high substrate selectivity, high yield of transformation of naturally occurring polyols, their ease of handling and recovery as well as recycling as they can be readily immobilized on many substrates . The use of lipase biocatalyst has been reported in the scientific literature mainly for the production of renewable plateform ester, amide or diphenol molecules for polyester, poly(ester‐urethane), epoxy resin [ , and non‐isocyanate polyurethane materials.…”

Lipase‐Catalyzed Synthesis of Furan‐Based Oligoesters and their Self‐Assembly‐Assisted Polymerization

“…[13,54,55] Specifically, only af ew reports are available on the lipase-catalyzed polycondensation of furan-based monomers. Bifunctional monomer 3a possesses two primary hydroxyl groups along with three secondary hydroxy groups, whereas 3b and 3c each have one primary hydroxy and carboxylic acidg roup.…”

Lipase‐catalyzed synthesis of aliphatic poly(β‐thioether ester) with various methylene group contents: thermal properties, crystallization and degradation

“…Enzymes are considered to be sustainable catalysts that exhibit high catalytic activities under mild conditions. Among them, lipases are some of the most studied and applied enzymes in industry due to their highly versatile and inexpensive character, and especially Candida antarctica lipase B (CALB) has attracted great interest for useful biodegradable functional polyester synthesis in recent years . The successful synthesis of aliphatic polyesters with functional groups including hydroxyl, mercapto, tertiary amine, vinyl, epoxy, oxetane, carboxyl, azide and so on through lipase‐catalyzed polymerization has been reported.…”