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SYNOPSISPolymerization of acrylamide was carried out with cerium( IV) -EDTA redox initiator system with and without electrolysis. The effect of temperature, time, cerium( IV), and EDTA concentrations on the polymerization yield and molecular weight were studied and compared with electrolytic conditions. At low concentrations of cerium( IV ) the electrolytic method continuously supplying Ce ( IV ) from Ce (111) has an advantage over the nonelectrolytic method for which polymerization did not occur under these conditions. A possible polymerization mechanism is suggested.

SYNOPSISAcrylamide polymerization by Ce ( IV) -polyaminocarboxylic acids, i.e., EDTA, DTPA, EGTA, and NTA, which have strong chelating properties, have been studied at different

The oxidative matrix polymerization of pyrrole (Py) by Ce(IV) in the presence of Polyacrylic acid (PAA) has been studied to obtain water‐soluble and insoluble products. The role of the PAA, Pyrrole, and Ce(IV) concentration, order of component addition, the structure of polymer matrix (PAA, Hydroxy Ethyl Cellulose (HES), Poly‐N‐vinylpyrrolidone (PVP)], and model unit of PAA (propionic acid), on the polymerization system were investigated. Interaction of PAA with insoluble polypyrrole (PPy) and the interpolymer complex formation were investigated along with the aggregation of PPy onto the matrix polymer followed by spectral shifts. FTIR results of insoluble products obtained from the PAA–Py–Ce(IV) system and solubility of the system is explained in light of the mechanism of the polymerization of pyrrole on the polymer matrix. © 1995 John Wiley & Sons, Inc.

Temperature‐ and pH‐sensitive copolymers and terpolymers of N‐isopropylacrylamide (NIPAAm) with itaconic acid (IA), monomethyl itaconate (MMeI), monobutyl itaconate (MBuI), monooctyl itaconate (MOcI), monocetyl itaconate (MCeI), and dimethyl itaconate (DMI) were prepared by free radical solution polymerization method. The dependence of coil‐to‐globule transition on pH and composition, molecular structures, and reactivities of monoalkyl itaconates, molecular weight distributions, and glass transition temperatures of copolymers and terpolymers were investigated using FT‐IR and UV–visible spectroscopic techniques, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and acid–base titration methods. The temperature‐/pH‐dependent coil‐to‐globule transition measurements showed that, upon increasing the content and length of alkyl chains, the lower critical solution temperatures (LCSTs) were shifted to higher temperatures. This meant that with increase in the length of hydrophobic alkyl chain in the monoitaconates intramolecular intreactions between the carboxyl groups were suppressed and LCSTs increased. The aqueous solution behaviors of NIPAAm/IA/DMI terpolymers also revealed that, even if the terpolymer hydrophobicity is increased by adding DMI units, the presence of IA units overcame the decrease in hydrophilicity of the terpolymers. The presence of DMI units in the terpolymers balanced the hydrophilic character of IA. DSC results supported the ones obtained from the pH‐dependent coil‐to‐globule transition measurements. An increase in both the chain length of alkyl groups attached to the monoitaconates and the contents of the mono‐ and dialkyl itaconates in the copolymers and terpolymers decreased the Tgs. In the case of NIPAAm/IA and NIPAAm/MMeI copolymers, the presence of the carboxyl groups forming hydrogen bonds increased the Tg, while the monoalkyl and dialkyl itaconates such as MBuI, MOcI, MCeI and DMI lead to a decrease in Tg of copolymers and terpolymers because of the suppression of intramolecular interactions (resulting from the COOH and COO− groups) through the longer alkyl spacers. The dependence of the thermosensitivity of these NIPAAm copolymers and terpolymers on different conditions of pH, and the nature and content of comonomers suggests that they can be useful in biotechnology and drug delivery applications which involve small changes in pH and temperature. Copyright © 2009 John Wiley & Sons, Ltd.