Hydrolases Part I: Enzyme Mechanism, Selectivity and Control in the Synthesis of Well-Defined Polymers - Enzymatic Polymerisation - page 54

Hydrolases Part I: Enzyme Mechanism,
Selectivity and Control in the Synthesis
of Well-Defined Polymers

Martijn A.J. Veld and Anja R.A. Palmans

Abstract Lipases are highly activity in the polymerization of a range of monomers.
Both ring-opening polymerization of cyclic esters and polycondensation reactions
of AA-BB and AB monomers have been investigated in great detail. This paper
reviews the increased understanding in enzymatic strategies for the production of
well-defined polymers. Major advantages of enzymatic catalysts are the relatively
mild reaction conditions, and the often-observed excellent regio-, chemo-, and enan-
tioselectivity that allow for the direct preparation of functional materials. However,
as a result of the monomer activation mechanism, polymers of low polydispersity
and low quantitative degree of endgroup functionality are difficult to attain. A wide
variety of (co)polymers have been synthesized and explored in a variety of applica-
tions using lipase catalysts.

Keywords (Co)polyesters · Lipase · Mechanism · Polycondensation · Ring-

opening polymerization

Contents

1 Introduction .................................................................................... 56

2 Reaction Mechanism of Lipases and Implications for Monomer Acceptance

in the Acylation and Deacylation Step ....................................................... 57

3 Polyesters ...................................................................................... 59

3.1 Lipase-Catalyzed ROP of Cyclic Esters ............................................... 60

3.2 Lipase-Catalyzed Polycondensation Reactions ....................................... 66

4 Polycarbonates ................................................................................. 68