Lipase-Catalyzed Degradation of Polyester in Supercritical Carbon Dioxide

Enzyme-Catalyzed Synthesis and Chemical Recycling of Polyesters

“…Takamoto et al reported that the lipase-catalyzed degradation of PCL in the presence of acetone produced an oligomer of lower molecular weight (less than 500) in scCO 2 , which can be polymerized by the same catalyst. [126] Similar results were obtained such that PCL beads were transformed in scCO 2 in the presence of a small amount of water and lipase to produce repolymerizable oligomers having a M -n of about 500. [127] The produced CL oligomer was again polymerized with lipase CA by a dehydration process to yield a PCL having a M -n greater than 80 000.…”

“…[125] Also, the lipase-catalyzed degradation of PCL in scCO 2 as the substitute for the organic solvent using lipase CA has been reported. [126,127] The scCO 2 is expected to be an environmentally benign solvent. These chemical recycling systems using an enzyme will establish a novel methodology for sustainable polymer recycling.…”

Lipase-catalyzed selective transformation of polycaprolactone into cyclic dicaprolactone and its repolymerization in supercritical carbon dioxide

“…The enzymatic polymerization of ε ‐CL proceeded in scCO 2 to give PCL with an M n higher than 10 4 7. Lipase‐catalyzed degradation of PCL into the corresponding oligomers in scCO 2 8,9 as the substitute for the organic solvent and ring‐opening polymerization of ε ‐CL initiated with dibutyltin dimethoxide in scCO 2 10 at 40 °C have also been reported.…”

Biomacromolecules and Bio‐Related Macromolecules

“…Lipase-CA-catalyzed hydrolytic degradation of poly(e-CL) occurred in scCO 2 under mild reaction conditions. [186,187] The addition of small amounts of acetone gave the corresponding oligomers with molecular weights of less than 500, which could in turn be polymerized by the same catalyst. The presence of traces of water also promoted the degradation of poly(e-CL) in scCO 2 .…”