Reaction of sodium salt of benzoic acid with methacryloyl chloride pro
vides an anhydride which is polymerized by the radical method or copol
ymerized with various percentages of ethylene glycol dimethacrylate to
obtain crosslinked products. Hydrolysis reactions of the resulting po
lymers were carried out in various aqueous solutions and the rate of r
elease of benzoic acid (simulator of drug) seems to depend both on the
percentages of crosslinking comonomer and on the pH of the solution.
A model of this delayed release of benzoic acid is also proposed. (C)
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