polyvinylpyrrolidone

Hydrogel membranes based on copolymers of 2-hydroxyethyl methacrylate with polyvinylpyrrolidone, modified with inorganic additives were synthesized. The influence of montmorillonite and silver on the properties of synthesized composite hydrogel membranes was studied. It was established that montmorillonite improves the mechanical properties of membranes, but slightly reduces their permeability. The chemistry of the recovery reaction of silver from its salts using polyvinylpyrrolidone as a reducing agent and stabilizer is proposed.

The article presents the results of a study of the influence of the molecular weight of polyvinylpyrrolidone on the properties of two-layer hydrogel/polycaproamide membranes. Composite membranes are obtained by the developed method, which consists in the formation of hydrogel membranes with subsequent deposition from a solution into their outer surface of a reinforcing layer based on polyamide modified with polyvinylpyrrolidone.

The peculiarities of modifying polyamide 66/6 and polystyrene thermoplastics with polyvinylpyrrolidone in the viscous state have been studied. By applying in-strumental methods, the changes in morphology and phase transitions of modified materials have been revealed. The influence of the modifier on the strength and thermo-physical properties of the researched thermoplastics was determined.

Composite materials based on copolymers of polyvinylpyrrolidone and 2-hydroxyethylmethacrylate with combined fillers consisting of metal powders and graphite were obtained by the method of polymerization filling. The developed materials are characterized by sufficiently high physical and mechanical properties, increased electrical conductivity and water content. It was established that the addition of graphite to metal-filled copolymers increases the sensitivity of the electrical resistance of composites to moisture changes.

The regularities of obtaining polylactide film composite materials with simultaneous silver nanoparticles formation were researched. The influence of the nature of polylactide and its structure (amorphous and amorphous-crystalline), of the glycerin plasticizer on the solvent evaporationkinetics  was determined. To give polylactide composites fungicidal properties, the silver reduction reaction by the interaction of argentum salts with polyvinylpyrrolidone was applied. A main technological scheme for obtaining films based on polylactide with fungicidal properties is proposed.

The possibility of using hydrogels based on copolymers of polyvinylpyrrolidone with 2 hydroxyethylmethacrylate to saturate them with plant extracts was established. Hydrogel materials were obtained with extracts of Calendula officinalis and Arnica montana. The sorption capacity of the hydrogels regarding the extract data was determined.

The regularities of obtaining silver nanoparticles in the presence of polyvinylpyrrolidone, which was both a reductant and a stabilizer of nanoparticle dispersion, have been studied. The influence of such factors as temperature, polyvinylpyrrolidone amount, concentration and nature of silver salts on the shape and size of nanoparticles has been established. The chemistry of the silver salts and polyvinylpyrrolidone reaction with the formation of vinylsuccinimide units in the structure of macromolecules has been proposed, which is confirmed by the results of IR spectroscopy.

The paper presents the results of the study of copolymerization of 2-hydroxyethylmethacrylate (HEMA) with polyvinylpyrrolidone (PVP) under the action of two-component initiation systems of iron (II) sulfate/radical type initiator. The influence of the nature of the radical initiator (In) in the FeSO4/In system on the behavior of the polymerization of HEMA/PVP compositions, structural parameters of the polymer matrix network and properties of hydrogels based on pHEMA-gr-PVP copolymers were established.

The impact of the vinyl monomers nature, concentration, and temperature on the kinetics of dispersion polymerization in the presence of polyvinylpyrrolidone was studied. The optimal technological parameters of the copolymer synthesis process are determined. It is defined that the properties of dispersion polymerization depend on the process conditions.

The research results of surface adsorption magnitude and tensile strength of combined polyamide-hydrogel membranes, depending on the content of the hydrogel lining membrane are presented in the article. It was found that the molecular weight variation of PVP, both in the structure of copolymer and in modifying blend, as well as the time of staying hydrogel film in the modifying solution allow to regulate the properties of combined membranes directly, in particular, its strength and permeability.