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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 ?H=-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 Ea =44.51±5.35?kJ?mol-1, preexponential constant lnA=15.47±1.38, entropy of polymerization ?S=-25.14?J?mol-1?K-1. The effect of reaction conditions on the molecular weight of poly(D,L-lactide) was shown.

SUBMITTER: Kalinin KT

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

REPOSITORIES: biostudies-literature

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

Kalinin Kirill T KT Sedush Nikita G NG Dmitryakov Petr V PV Chvalun Sergei N SN

ChemistryOpen 20201013 10

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 <i>ΔH</i>=-17.8±1.4 kJ mol<sup>-1</sup>. Kinetic curves of D,L-lactide polymerization and propagation rate constants were determined for polymerization with zirconium acetylacetonate ...[more]

PMID: 33083201

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