Ring-opening polymerizations （ROP） of cyclic monomers for the synthesis of biodegradable polymers have attracted growing research interest from polymer chemistry. As a green synthetic strategy，enzymatic ROP still suffers from bottlenecks，such as low efficiency and broad molecular weight distribution. In contrast to the traditional batch reactor，a microreactor featuring a huge surface-to-volume ratio and continuous flow characteristics enables process intensification and allows for applications in organic and polymeric synthesis. Recently，remarkable advantages have been demonstrated by the combination of microreactor-based flow chemistry and enzymatic ROP，such as accelerated apparent polymerization rate constant，lower polydispersity （Đ），and higher end-group fidelity. Moreover，continuous flow chemo-enzymatic platforms have been developed to efficiently prepare biodegradable block and bottlebrush copolymers. This review focuses on the advances in microreactor-based continuous flow enzymatic and chemo-enzymatic ring-opening polymerizations for the synthesis of biodegradable polymers. The challenges and opportunities are also discussed with the target for the development of biocatalysis and biodegradable polymers.

Contents

1 Introduction

2 Synthesis of biodegradable polymers by continuous flow enzymatic ROP

2.1 Water as initiator

2.2 Alcohol as initiator

2.3 Optimization of polymerizations

3 Synthesis of functional biodegradable polymers by continuous flow chemo-enzymatic routes

3.1 Block copolymers

3.2 Bottlebrush polymers

3.3 Polymer stabilized nanoparticles

4 Conclusion and outlook