The equilibrium and kinetics of proteins sorption and desorption by oppositely charged lightly crosslinked polyelectrolytes (#PE) were studied. The driving force of the sorption is provided by interpolyelectrolyte addition reaction (IPAR) between oppositely charged ionic groups of protein and #PE resulting in protein–#PE complex (#PPEC) formation. The capacity of different #PEs with respect to the proteins in neutral salt‐free aqueous solutions is rather high, exceeding that of the known heterogeneous crosslinked polyelectrolyte sorbents commonly used for protein sorption in practice. The dependence of the capacity of #PE on pH and the salt concentration in the environmental solution has been revealed and investigated. The equilibrium of IPAR is shifted to the original components under the corresponding pH shift or adding a simple salt. As a result the protein releases into the surrounding solution. The rate of protein uptake and release is also controlled by the pH or/and the ionic strength of the solution. The data obtained show that #PE can be used to design the crosslinked polyelectrolyte constructs for controlled uptake and release of proteins. Copyright © 2003 John Wiley & Sons, Ltd.

SYNOPSISThe kinetics of radical polymerization of acrylic and methacrylic acids and their salts in aqueous solutions have been studied. A considerable increase in the polymerization rate at an increase in pH in the alkalinity area has been detected, the general trend of the rate-enhancement being specifically dependent on the type of cation present in the solution. On the basis of the set of the experimental data an assumption was made on the kinetic role of ion pairs in the radical polymerization of ionizable monomers. Formation of ion pairs results in the increase of the elementary propagation rate constant Kp. Rotating sector measurements for individual kinetic constant confirmed the advanced hypothesis. The importance of the conformational state of polyelectrolyte growing chains in the kinetics of radical polymierzation of ionizable monomers has been shown. Participation of ion pairs in the propagation step leads to marked stereochemical effects and, in certain cases, to the formation of practically stereospecific polymers. 173

The hydrogen bond in dilute solutions of different polyethylene glycol) monodisperse fractions with molecular weights from 300 to 6000 has been studied in carbon tetrachloride by IR spectroscopy using a computer for spectrum resolution. The dependences of the equilibrium constants on the polymer molecular weight have been determined for different forms of intraand intermolecular hydrogen bonds.

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