High‐Molecular‐Weight Polycarbonates Synthesized by Enzymatic ROP of a Cyclic Carbonate as a Green Process

Abstract

High-molecular-weight PTeMC and PHMC were prepared by the lipase-catalyzed polymerization of butane-1,4-diol or hexane-1,6-diol and diphenyl carbonate via the formation of a cyclic dimer by a green process. Cyclic carbonate dimers were prepared by the lipase-catalyzed condensation of diphenyl carbonate with butane-1,4-diol or hexane-1,6-diol in dilute toluene solution using an immobilized lipase from Candida antarctica, and was followed by the ring-opening polymerization of the cyclic dimer in bulk with the same lipase to produce PTeMC with M(w) = 119 000 g . mol(-1) and PHMC with M(w) = 399 000 g . mol(-1), respectively. Additionally, enzymatic polymerization of cyclic carbonate dimer was analyzed with respect to the K(m) and V(max) for the lipase.

One-pot synthesis of high-molecular-weight aliphatic polycarbonates via melt transesterification of diphenyl carbonate and diols using Zn(OAc)2 as a catalyst

“…Here, the co-product, phenol, can be separated easily and reused in the DPC synthesis via transesterification with DMC or oxidative carbonylation [20].The reaction parameters such as catalyst concentration, reaction temperature and time on the M w , polydispersity index (PDI) and yield of PBC were investigated in detail to obtain the optimum conditions. In this work, we present our results on use of transition metal acetates as catalysts for directly one-pot bulk transesterification of DPC and aliphatic diols at equimolar amounts to one-pot produce high-molecular-weight APCs.…”

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

“…Unfortunately, polymerizations employing diethyl carbonate require the use of an excess diethyl carbonate [55]. Nevertheless, polymers with molecular weight of 40 kDa were achieved within 16 h. Also, the polymerization of diphenyl carbonate with butane-1,4-diol or hexane-1,6-diol via the formation of a cyclic dimer produced polymers with molecular weights ranging from 119 to 339 kDa [93].…”

“…As a result, commercially available carbonates such as diethyl carbonate [55][56][57] or diphenyl carbonate [93] were evaluated in polycondensation reactions with diols to prepare polycarbonates since they allow a broader spectrum of polymers to be accessed. Unfortunately, polymerizations employing diethyl carbonate require the use of an excess diethyl carbonate [55].…”

Chemo-enzymatic Synthesis and Properties of Novel Optically Active Cationics Containing Carbonate Linkages

“…These results indicate that the AEI formation of R -S12iPr is easier than that of S -S12iPr under the same conditions. As the ratedetermining step of carbonate-containing compounds is reported to be the nucleophilic attack of water 30 , it could be thought that the higher enzymatic hydrolyzability of R Fig. 2 Time course of the enzymatic hydrolysis of (R)-S12iPr ( ), (S)-S12iPr ( ), and rac-S12iPr ( ) in toluene containing a small amount of water.…”