Microstructure Analysis and Model Discrimination of Enzyme-Catalyzed Copolyesters.

Area of Science:

• Polymer Chemistry
• Spectroscopy
• Biocatalysis

Background:

• Poly(ε-caprolactone-co-δ-valerolactone) (PCV) copolymers are synthesized using lipase catalysis.
• Understanding comonomer sequence distribution is crucial for tailoring copolymer properties.

Purpose of the Study:

• To analyze comonomer sequence distributions in PCV copolymers.
• To determine the copolymerization kinetics model using NMR spectroscopy.

Main Methods:

• ¹³C nuclear magnetic resonance (NMR) spectroscopy was employed.
• Analysis of dyad and triad fractions from well-resolved NMR peaks.

Main Results:

• NMR spectra allowed precise quantification of dyad and triad fractions.
• Monomer sequence distributions confirmed lipase-catalyzed copolymerization follows a terminal model.
• Compositional analysis alone could not distinguish between kinetic models.

Conclusions:

• ¹³C NMR spectroscopy is an effective tool for analyzing PCV copolymer sequences.
• The study elucidates the kinetics of lipase-catalyzed copolymerization.
• This NMR approach facilitates rapid characterization of biocatalyzed copolymers.