Polymer, Vol.37, No.6, 1005-1011, 1996
Hydrogels Based on Graft-Copolymerization of 2-Hydroxypropyl Methacrylate Acrylate Mixtures on Amylose - Swelling Behavior
Hydrogels were prepared by simultaneous graft copolymerization on amylose of 2-hydroxypropyl methacrylate with different acrylates (methyl acrylate, ethyl acrylate and butyl acrylate) using eerie ammonium nitrate as initiator. Similarly, another series of grafted samples with a 50/50 (mol/mol) composition of hydroxylic/non-hydroxylic monomers with 34 mol% of ethylene glycol dimethacrylate were prepared. Percentages of crude grafting (%CG), polymerized monomer (%PM) as well as equilibrium water content (%EWC) were analysed as a function of the monomer composition in the initial mixture and the degree of crosslinking. As the proportion of hydroxylic monomer in the copolymers increased, a slight rise in %EWC was observed and a higher increase as the alkyl side-group length of acrylates decreased. The swelling behaviour had only an appreciable variation at basic pH, even achieving similar values to those of amylose when diethylene glycol dimethacrylate was added.