Polymers carrying a hydrolyzable ester function and bactericidal quaternary ammonium salts were successfully synthesized in 2 steps. The first one was the modification of hydroxyl functions of poly(vinyl alcohol) by chloroacetic anhydride. The structure of synthesized polymers was confirmed by infrared (IR), H-1-, and C-13- nuclear magnetic resonance (NMR). The kinetic results were consistent with a 1-order reaction, and the activation energy in the case of total modification was found to be 16.8 kJ mol(-1). The second step was the quaternization of the pendant chlorine atom with a long alkyl chain or aromatic tertiary amines. The percentage of grafting was almost total, except with 3-diethylaminophenol, probably due to steric hindrance. The thermal degradation of polymers was studied. Side chains carrying quaternary ammonium salts begin to degrade at 168 degrees C with the emission of chloride and amine compounds. At about 250 degrees C, acetic and chloroacetic acid are evolved due to acetate and chloroacetate side chains.