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A dynamic model is proposed for the photopolymerization of 1,6‐hexanediol diacrylate (HDDA) with the bifunctional initiator bis‐acylphosphine oxide (BAPO) in the presence of oxygen. The model tracks time‐varying concentrations of monomer, oxygen, and different radical end groups using ordinary differential equations. An analytical expression is derived for the mass‐transfer of oxygen. Oxygen‐related parameters are estimated using real‐time Fourier‐transform infrared reflection (FTIR) vinyl conversion data, which were collected during polymerization of HDDA films with different thicknesses, initiator concentrations, and light intensities. The resulting model and parameter estimates provide good predictions for experiments involving thin films up to 12 μm, with BAPO levels ranging from 1 to 4 wt.% and relatively low light intensities (200–1000 W/m2). [ABSTRACT FROM AUTHOR]

A comprehensive dataset containing 1779 measured values, collected from seven experimental runs, is used for parameter estimation in a model for batch polycondensation of biobased 1,3‐propanediol. The data are from dynamic experiments conducted between 160 and 180 °C using a super‐acid catalyst with concentrations between 0.1 and 0.25 wt%. The model accounts for generation, consumption, and evaporation of linear and cyclic oligomers, the inhibitory influence of water on the rate of polycondensation, and the dynamic behavior of an overhead condenser. In total, the model contains 70 kinetic, transport, and thermodynamic parameters. A mean‐squared‐error criterion reveals that the influence of temperature on mass‐transfer coefficients is significant. The model provides a good fit to the data and also gives reliable predictions of validation data that are not used in parameter estimation. Typical deviations between model predictions and data are within 1.75% of average measured values for linear and cyclic oligomers. [ABSTRACT FROM AUTHOR]