| Abstract: | Cationic poly(N-isopropylacrylamide) (NIPAM) copolymer latexes have been prepared at 70°C using methylene-bisacrylamide (MBA) as the crosslinking agent,2-2′-azobis-(2-amidinopropane hydrochloride) (V50) as the initiator and in the presence of 2-aminoethyl-methacrylate hydrochloride (AEM). It was found that the concentration of AEM plays a major role in the polymerization kinetics and particle nucleation. However, too high a concentration (2–5 mol%/NIPAM) caused the latex to be polydispersed together with the production of large amounts of polyelectrolytes. The presence of surface amino groups on the final particles under the protected form was revealed both by an ultraviolet spectrometry and nuclear magnetic resonance methods. It was indirectly evidenced through the electrophoretic mobility behavior of the latex particles (below and above the lower critical solubility temperature of the poly(NIPAM)) as well as by their stability against a monovalent electrolyte. |
