摘要

Bulk free-radical copolymerization of styrene and 2-hydroxyethyl acrylate (HEA) is investigated experimentally at 50 degrees C using pulsed-laser polymerization and computationally using ab initio simulations. Arrhenius parameters for HEA chain-end homopropagation are A = 1.72 x 107 L mol-1 s-1 and Ea = 16.8 kJ mol-1, based on experiments between 20 and 60 degrees C. Copolymer composition data are well fitted by the terminal model with reactivity ratios rST = 0.44 +/- 0.03 and rHEA = 0.18 +/- 0.04, but the variation in the propagation rate coefficient with monomer composition is underpredicted. Results are compared with computational predictions assuming the terminal as well as the penultimate unit effect (PUE) model. Intramolecular H-bonding is shown to have a significant influence on PUE calculations. Discrepancies between computational predictions and experiment are attributed to the influence of intermolecular H-bonding.

  • 出版日期2012-8-28