1 Department of Polymer Science, The University of Akron, Akron, USA
2 Department of Chemistry, The University of Akron, Akron, USA
3 Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, USA
In this work we investigated the kinetics of the transesterification of divinyl adipate (DVA) with tetraethylene glycol (TEG) using Candida antarctica lipase B (CALB) as a biocatalyst at 50 °C under solventless conditions. We examd. the time-dependence of the reactions with various DVA/TEG ratios. Samples were taken at the specified times, and then the compn. and end group structures were analyzed by MALDI-ToF mass spectrometry. We found conditions under which polycondensation was minimized and sym. and asym. telechelic TEGs were obtained. Specifically, at DVA/TEG = 1.5 molar ratio 100% of the oligomers had divinyl end groups after 20 min reaction time. At DVA/TEG = 3 only vinyl end groups were detected after 5 min. HO-(TEG)n-Vinyl was maximized at 70% at DVA/TEG 1/1.5 molar ratio at 10 min reaction time, while ∼90% HO-(TEG)n-OH was obtained in 20 min with TEG excess.