Kinetics of D,L-Lactide Polymerization Initiated with Zirconium Acetylacetonate.

ABSTRACT: The kinetic of D,L-lactide polymerization in presence of biocompatible zirconium acetylacetonate initiator was studied by differential scanning calorimetry in isothermal mode at various temperatures and initiator concentrations. The enthalpy of D,L-lactide polymerization measured directly in DSC cell was found to be ΔH=-17.8±1.4 kJ mol^-1. Kinetic curves of D,L-lactide polymerization and propagation rate constants were determined for polymerization with zirconium acetylacetonate at concentrations of 250-1000 ppm and temperature of 160-220 °C. Using model or reversible polymerization the following kinetic and thermodynamic parameters were calculated: activation energy E_a =44.51±5.35 kJ mol^-1, preexponential constant lnA=15.47±1.38, entrop

SUBMITTER: Kalinin KT 

PROVIDER: S-EPMC7552909 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature