Kinetics and reaction mechanism of template polymerization investigated byconductimetric measurements. Part 3. Radical polymerization of acrylic acid in the presence of poly(N-vinylpyrrolidone)

Conductimetry was used for monitoring the radical polymerization of a weak electrolyte (acrylic acid) in aqueous solution and for determination of the kinetic parameters of the reaction (reaction order with respect to monomer , activation energy). The results obtained were consistent with those deter mined by other techniques (such as dilatometry) or expected from theory. Dilatometric and conductimetric measurements were also used to study the te mplate polymerization of acrylic acid onto poly(N-vinylpyrrolidone). Result s indicate that the reaction proceeds according to a pick-up mechanism. Complexes between poly(acrylic acid) and poly(N-vinylpyrrolidone) were alwa ys isolated in equimolar composition of the two polymers, regardless of the polymerization mixture composition. Spectroscopic evidence of the existenc e of strong interaction and intimate mixing of the two polymers in the comp lexes was found. An influence of the template molecular weight on the chain length of the forming poly(acrylic acid) was detected by means of viscomet ry. (C) 2000 Society of Chemical Industry.