V. N. Pavlyuchenko

Polymer hydrogels with the memory effect for immobilization of drugs

Hydrogels with the memory effect are synthesized from crosslinked copolymers of 2-hydroxyethyl methacrylate and functional monomers (acrylic acid or dimethylaminoethyl methacrylate) via the method of template synthesis with the use of the drug cephazoline as a matrix. It is shown that the hydrogels show an increased sorption activity against the target drug and a slow rate of drug release from the hydrogel (the memory effect) under certain conditions. In combination with cephazoline, these hydrogels may be regarded as a new prolonged-drug-release system for the treatment of infectious diseases.

Water-Resistant Films and Coatings Based on Cross-Linking Styrene-Acrylate Latex Copolymers

Water-resistant films and coatings were prepared from latexes of copolymers of styrene, n-butyl acrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, and methacrylic acid. The degree of cross-linking of the copolymers in the course of film formation and the water resistance of the films and coatings, associated with this parameter and evaluated by the water absorption and mechanical properties of wet films, were studied in relation to the gross composition of the latex copolymer, conditions of its synthesis, distribution of functional groups responsible for cross-linking in a latex particle, and temperature of film formation.

Polymeric hydrogels with memory effect for immobilization of binary drug combinations

Hydrogels with memory effect (imprinted hydrogels) with respect to a combination of cefotaxime and diclofenac were synthesized from 2-hydroxyethyl methacrylate and functional monomers (acrylic acid and N,N-dimethylacrylamide). The hydrogels obtained show increased ability to sorb cefotaxime and especially diclofenac. Prolonged release of cefotaxime was revealed, becoming more pronounced with an increase in the cefotaxime concentration in the solution from which it is sorbed with the hydrogel. The effect of selective sorption of diclofenac with imprinted hydrogels from the diclofenac-cefotaxime drug combination was discovered.

Organic-inorganic cross-linked structures prepared from reactive n-butyl methacrylate-3-(trimethoxysilyl)propyl methacrylate copolymers

The features of formation of organic-inorganic cross-linked structures prepared by copolymerization of n-butyl methacrylate with 3-(trimethoxysilyl)propyl methacrylate, followed by hydrolysis of the trimethoxysilane groups of the copolymers and condensation of the resulting silanol groups, were studied. The quantitative composition of the functional groups of the cross-linked copolymers was determined. The physicomechnaical and mechanical properties of the copolymers were studied in relation to the copolymer composition and conditions of hydrolytic condensation.

Proton-conducting membranes based on multicomponent copolymers

Preparation of proton-conducting polymeric composites via copolymerization of multicomponent monomeric systems using the interpenetrating polymer network preparation procedure is studied. The products are characterized by the protonic conductivity, water-retaining capacity, and mechanical properties. The approach used allows fabrication of membranes with a reasonable protonic conductivity over the temperature range 20–90°C. A possibility of modification of the proton-conducting materials with small additions of hydrolyzable organosilicon comonomers is analyzed. The structure of the resulting systems is examined by small-angle neutron scattering.

Styrene-acrylate copolymer plastisols with stable colloidal properties

Methods for the synthesis of emulsion-polymerized styrene-methyl methacrylate-methacrylic acid copolymers with different compositions and structures are proposed. Stable plastisols are obtained from these copolymers and phthalate plasticizers. Factors that affect the colloidal stability and rheological properties of the plastisols were studied. These are the polymer particle size, the type of surfactants used in emulsion copolymerization, the distribution of methacrylic acid units over the latex particle volume (uniform or gradient, with concentration rising from the particle center to periphery), the degree of carboxyl group neutralization with a base, and the nature of plasticizers. The plastisols obtained are characterized by a pseudoplastic flow. However, as the degree of carboxyl group neutralization in the copolymers is increased, the rheological properties of the plastisols approach those of Newtonian liquids.

Compound latexes for antistatic coatings

Compound latexes based on amine-containing styrene-acrylate copolymers and hollow particles of a polystyrene-based copolymer as a filler were studied. With this filler, it is possible to prepare antistatic pigmented coatings with increased surface hardness, decreased density, and surface resistivity ρs of the order of 108 Ω.

Segregation of polymers in the course of film formation from a mixture of latexes

Film formation from binary mixtures of latexes of thermodynamically incompatible polymers was studied. Partial segregation of the polymers in the course of latex film formation, causing asymmetry of the resulting films, was proved by IR Fourier spectroscopy. The influence of various factors on the segregation of polymers was examined.