Radically initiated polymerization of a methacryloylamido‐terminated saccharide, 1. Monomer synthesis, homopolymerization and characterizations

Abstract

A methacrylamido‐terminated saccharide, 6‐deoxy‐6‐methacryloylamido‐D‐glucopyranose (MAG), was synthesized using a new and easy pathway. Kinetics of the radically initiated solution homopolymerization of this monomer was investigated at 50°C using 4,4′‐azobis(4‐cyanopentanoic acid); the obtained k_p/k_t^1/2 value around 1.0 mol^−1/2 ċ L^1/2 ċ s^−1/2 is indicative of the strong ability of MAG to polymerize (k_p and k_t being the rate constants of propagation and termination, respectively). The chemical structure of the homopolymer, as analyzed by ¹³C NMR spectroscopy shows a tacticity which is in favor of a syndiotactic configuration resulting from the bulkiness of the side group. The dimensional characteristics of the polymers were studied by light scattering as an on‐line detection in size exclusion chromatography (SEC). As expected from the k_p/k_t^1/2 value, high weight‐average molecular weights were obtained. The small average radii of gyration were found to reflect a relatively compact structure in water due to inter‐ and intramolecular interactions; viscosity studies in various solvents as well as values of the second virial coefficient corroborate such a behavior which reflects that water is a poor solvent for poly(MAG).