Alkenyl‐functionalized precursors for renewable hydrogels design

A library of crosslinking chemistries for the hydrogel synthesis based on the hemicellulose acetylated galactoglucomannan (AcGGM) has been developed, demonstrated, and evaluated. A three‐step route was elaborated including (1) the carbonyldiimidazole activation of primary hydroxylated vinylic molecules such as acrylates, vinyl alcohols, and vinyl ethers, (2) the covalent coupling of the alkenyl precursors to the polysaccharide backbone hydroxyls, and (3) the radical crosslinking of pendant vinyl functionalities affording a hydrophilic network. Crosslinking strategies explored include redox initiation and photo initiation, with an effort to adapt the suggested synthesis routes to benign conditions. The different functionalization strategies were shown to influence the resulting gel's properties. Varying the crosslinking media was found to be a strong tool to tune the properties of the gels. Modifications were in all cases verified by means of NMR and FTIR, and the gels were characterized with respect to swelling capacity and rheological parameters. It was shown that by adjusting the synthesis parameters, the resulting properties of the AcGGM gels could be custom‐made for a given performance. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3595–3606, 2009