Presentation Type

Poster

Keywords

magnesium complexes, L-lactide, ϵ -caprolactone, ring opening polymerization

Department

Chemistry

Major

Chemistry, BA

Abstract

A series of bis-ligated magnesium complexes supported by tridentate ketoiminates containing electron-donating and electron-withdrawing groups were prepared. The complexes were characterized with 1H, 13C, and 19F NMR, absorbance spectroscopy, and x-ray crystallography. The complexes were assessed for their ring opening polymerization activity with L-lactide (L-lac) and ϵ-caprolactone (eCL) in binary catalyst systems with 4-fluorophenol at 100 °C. The magnesium complexes supported by ketoiminates bearing electron-donating groups yielded greater percentage conversions from monomers to polymers than those containing electron-withdrawing groups for both L-lac and eCL. The magnesium complexes were more efficient at polymerizing L-lac than eCL, and di-block copolymers of PCL-PLA were produced by the sequential polymerization of eCL followed by L-lac.

Faculty Mentor

Joseph M. Fritsch

Funding Source or Research Program

Summer Undergraduate Research Program

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L-Lactide and ϵ-caprolactone ring opening polymerization by binary catalysts systems that include bis-ligated magnesium complexes

A series of bis-ligated magnesium complexes supported by tridentate ketoiminates containing electron-donating and electron-withdrawing groups were prepared. The complexes were characterized with 1H, 13C, and 19F NMR, absorbance spectroscopy, and x-ray crystallography. The complexes were assessed for their ring opening polymerization activity with L-lactide (L-lac) and ϵ-caprolactone (eCL) in binary catalyst systems with 4-fluorophenol at 100 °C. The magnesium complexes supported by ketoiminates bearing electron-donating groups yielded greater percentage conversions from monomers to polymers than those containing electron-withdrawing groups for both L-lac and eCL. The magnesium complexes were more efficient at polymerizing L-lac than eCL, and di-block copolymers of PCL-PLA were produced by the sequential polymerization of eCL followed by L-lac.