Dynamic studies of molecular imprinting polymerizations

Mechanisms of interaction of a three-dimensional polymer with solutes are of interest in the development and function of synthetic biomimetic polymers. We have investigated the effects of template/monomer interactions and template concentration on conversion and polymerization rates of a molecularly imprinted polymer. Copolymers of 2-hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol) dimethacrylate (PEG600DMA) were prepared in the presence of glucose. The polymerization reaction kinetics of non-imprinted networks as well as those imprinted with glucose at concentration ratios of [HEMA]/[Glucose] between 11 and 1 were monitored in situ by ATR-FTIR spectroscopy and differential photocalorimetry (DPC). The rates of polymerization for imprinted polymers showed an early lag period followed by a late autoacceleration, indicative of the complexation between monomer and template. Hydrogen-bonding was also observed using FTIR through the C=O (carbonyl) bond of the monomers by FTIR. A significant effect of the template on conversion and polymerization rate of imprinted polymers was observed compared to non-imprinted ones. These values provide guidelines for kinetic models of interacting systems. (C) 2004 Elsevier Ltd. All rights reserved.