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The paper deals with the investigation results of nanocomposites based on polyamide-6 (PA6) and montmorillonite (MMT) intercalated by polyvinylpyrrolidone (PVP). Nanocomposites were obtained by mix...

Nickel-filled composite copolymers of 2-hydroxyethylmethacrylate with polyvinylpyrrolidone and hydrogels based on them were obtained by the methods of polymerization filling and polymerization with...

This work deals with the development of method for obtaining polyamide and montmorillonite based nanocomposite, which was modified with polyvinylpyrrolidone by mixing in formic acid solution. The structure and thermophysical properties of the obtained nanocomposites were investigated by X-ray, differential-thermal, thermogravimetric and IR spectroscopic analyzes. It has been found that nanomodified polycaproamide has a higher crystallinity and higher thermal stability than the original PA-6, and is characterized by considerably higher melt fluidity. The presence of polyvinylpyrrolidone and exfoliated montmorillonite in the nanocomposite structure was experimentally confirmed.

We establish the regularities of formation of composite polymeric hydrogel membranes based on liquid-structured copolymers of 2-hydroxyethyl methacrylate (HEMA) with polyvinylpyrrolidone (PVP) modified by a thin layer of a mixture of polyamide-6 (PA-6) and PVP by the method of diffusion deposition from a formate solution. We study the physical and mechanical properties of the obtained composite membranes depending on the molecular weight of PVP in the structure of the copolymer and in the modifying mixture, as well as on the degree of adsorption of the PA-6–PVP mixture on the source hydrogels. It is shown that the strength of hydrogel membranes increases with the molecular weight of PVP in the hydrogel matrix structure and with its decrease in the PA-6–PVP formate solution.

The effect of grooves number in the feed section and screw length as well as filler nature and content on the productivity of single-screw extruder has been examined. Compositions based on polypropylene with glass fibers, talc and chalk were used for research. It is established that the number of grooves in the feed section and the length of the screw differently affect the productivity of a single screw extruder depending on the nature and content of the filler. This effect is shown to be most significant for polypropylene compositions with mineral powders (talc and chalk).

The structure and thermal characteristics of nanocomposites based on polyvinyl alcohol (PVA) and montmorillonite (MMT) intercalated with polyvinylpyrrolidone were investigated by X-ray diffraction analysis and differential scanning calorimetry. The modification of PVA with intercalated MMT reduces the degree of crystallinity of the resulting nanocomposites but significantly increases their thermal stability. Under ultrasound, the intercalated MMT was completely distributed in a PVA solution and formed a monocrystalline structure. Films based on PVA with modified MMT were cross-linked at 110°C in the presence of 5 wt% acrylic acid and 0.5 wt% Ferrous(II) sulfate as an initiator. The formed films have a homogeneous cross-linked structure.

Metal-filled hydrogel films based on polyvinylpyrrolidone with 2-hydroxyethyl methacrylate copolymers were obtained by centrifugal method. It is determined the influence of the content of metal powder filler, technological parameters of processing and formulation of initial polymer-monomer composition on the physical-mechanical properties of the obtained composition film materials. It was determined that obtained metal-filled films are characterized by the anisotropy of the physical-mechanical properties of surfaces.

Досліджено взаємозв‘язок фізико-механічних та технологічних характеристик новостворених наноком- позитів на основі суміші ПП/ПА-6 з модифікованим за допомогою ПВП монтморилонітом. Показано суттєвий вплив поліаміду, який модифікований інтеркальованим за допомогою ПВП монтморилонітом, на технологічні, фізико-механічні властивості та теплостійкість поліпропілену. Встановлено, що показник текучості розплаву одержаних композитів збільшується більше, ніж у 2 рази, у порівнянні з чистим ПП. Показано, що внаслідок змішування ПП з модифікованим поліамідом значно збільшується твердість, модуль пружності та теплостійкість композитів у порівнянні з чистим ПП. При цьому зменшуються у 2 рази відносне видовження та у 4 рази вимушено-еластична деформація композитів. The interrelation of physico-mechanical and technological characteristics of newly created nanocomposites on the basis of polypropylene (PP)/polyamide (PA-6) mixture with PVP-modified montmorillonite has been investigated. The significant impact of modified polyamide on technological, physical and mechanical properties and heat resistance of polypropylene has been determined. It has been established that the melt flow index of the resulting composites increases by more than 2 times, compared with pure PP. The hardness, modulus of elasticity and heat resistance of composites were found to be considerably increased in comparison with pure PP due to polypropylene mixing with modified polyamide. At the same time, the percent elongation and the forced-elastic strain of composites are reduced by 2 times.

It was determined that novolac phenol-formaldehyde resin modification by polyvinylpyrrolidone and epoxy-dianic resin results in a significant improvement of thixotropic characteristics and enamel technological effectiveness and in physico-mechanical properties and thermostability improvement as well. The developed modified composition is characterized by high index of thixotropy in contrast to phenol-formaldehyde resin containing urotropine.

In connection with the significant complication of research objects of technological systems and the considerable increase in expenses for carrying out experimental research, improving the mathematical modeling methods of these systems is a current problem. By using the means of mathematical modeling and optimization, the calculation of the main technological parameters of the formation method of film hydrogel products based on silver-filled copolymers of 2-hydroxyethylmethacrylate with polyvinylpyrrolidone was performed. The technological parameters of the polymerization processes, chemical reduction of silver ions, and centrifugal formation of the film cloth were substantiated. These are the components of the technological process, which occurs in one stage in the form of a centrifugal unit. By using the obtained results, silver-filled films were obtained, which are characterized by unique properties and can be used in the treatment of trophic ulcers of lower limbs.

This paper presents the research results of the copolymer structure and properties of 2-hydroxyethylmethacrylate (HEMA) with polyvinylpyrrolidone (PVP) and their hydrogels, obtained by block polymerization in the presence of iron sulfate (II). By the methods of chemical analysis, IR spectroscopy, Thermogravimetric (TG) and Differential Thermal Analysis (DTA), the course of grafted copolymerization of HEMA on PVP with the formation of a cross-linked copolymer was confirmed. The results received by scanning electron microscopy showed that due to the copolymerization of HEMA with PVP, macroporous hydrogels with a pore size of 10–30 μm were obtained. The peculiarities of the structure formation of the obtained copolymers depending on the initial composition formulation were established and their structural parameters were investigated: PVP grafting efficiency, PVP content in copolymer, molecular weight of internodal fragment of polymer network, crosslinking degree, and crosslinking density. The interrelation of sorption–diffusion, physical–mechanical and thermophysical properties along with the structure of the obtained materials was proved. It was shown that with the increasing PVP content in the original composition, the efficiency of its grafting and crosslinking density of the polymer network decreased, but the surface hardness, heat resistance, sorption capacity of copolymers in the dry state, as well as ion permeability and elasticity in the swollen state increased, while their tensile strength deteriorated. It is proved that by changing the original composition formulation it is possible to change the structure and hence the properties of the copolymers in the desired direction.

The results of studies of the electrically controlled elements of optical systems based on hydrogel - electrochromic polymer with conjugated π-electron system are shown. One important feature of co...

The effect of small polyamide additives modified with polyvinylpyrrolidone and montmorillonite on polypropylene technological properties and heat resistance has been researched in the work. It has been determined that the melt flow index of the obtained composites increases by more than 2 times in comparing with pure PP. It has been shown that adding to polypropylene a small amount of polyamide which is modified by montmorillonite-polyvinylprolidone mixture significantly increases the heat resistance of the material. The displacement of the beginning of thermal-oxidation destruction and burning samples into the range of higher temperatures on 114-123 oC dependently on the modified polyamide content has been observed.

The paper is dedicated to development of a method for producing structured waterproof films based on polyvinyl alcohol (PVA) and montmorillonite-polyvinylpyrrolidone mixture (MPM) to research the impact of borax, pH-environment and MPM content on the rheological properties PVA solutions and water absorption capacity of films based on them. By experimental studies have been established that the montmorillonite- polyvinylpyrrolidone mixture significantly affects on viscosity the characteristics of the solution polyvinyl alcohol provided their mixing in the ultrasonic field. Composition of traces of sodium tetraborate in the aqueous solution eminent by the highest rates of viscosity. Also, designed compositions considerable influence pH at the viscosity, particularly compositions obtained in weakly alkaline environment with higher values of relative viscosity than compositions obtained in neutral and acidic environments. Simultaneously, is the best water resistance and mechanical properties of films obtained in an acidic environment. The optimum from the standpoint of durability and water resistance is a composition of PVA:MPM = 12:1 and because, depending on the contents of the MPM and pH characteristics films based on PVA can be adjusted over a wide range, which would expand the scope.

We established in the present work the regularities for obtaining homogeneous nanocomposites based on the mixture of PP/PA-6 with montmorillonite modified using PVP. In these nanocomposites, PA-6 and MMT contribute to the increase in thermal resistance of the material, while PVP improves compatibility between polar PA-6 and hydrophobic PP. The goal of the present work was to investigate by applying the methods of thermogravimetric analysis a correlation between thermal characteristics of the newly-created nanocomposites based on the mixture of PE/PA-6 with montmorillonite, modified using PVP, and to determine the optimal composition of a nanocomposite with enhanced thermal resistance and a wide temperature interval of the viscous-fluid state. On the basis of experimental data, it was found that the mixtures of polypropylene with polyamide modified by the montmorillonite-polyvinylpyrrolidone mixture are distinguished by the higher thermal resistance compared with the starting PP. It is established that at a content of the modified polyamide in the mixtures with polypropylene within 30 % by weight, samples of the composite are characterized by the highest thermal resistance ‒ weight loss of such composites in a temperature range of 218‒322 oC is only 7.1 %, temperature of the onset of thermo-oxidation destruction is 300 oC. It is shown that the developed nanocomposites have wider temperature intervals of the viscous-fluid state – 126–300 oC. This makes it possible, by changing the modes of processing, to influence the structure and properties of products, especially taking into account the difference in crystallization of the material depending on the conditions and the method of processing. It is established that the most suitable for application and processing is the mixture of polypropylene with modified polyamide in the ratio 70:30 % by weight, respectively

The synthesis and study of metal-containing hydrogels, particularly those filled with nickel nanoparticles, is currently of interest to many researchers. This paper presents the results of an investigation of the structure and properties of Ni(0)-filled composites on the basis of 2-hydroxyethylmethacrylate copolymers (HEMA) with polyvinylpyrrolidone (PVP) and their hydrogels. The authors of the article are the first who propose the method to produce these materials by combining the processes of polymer matrix synthesis and a reduction of Ni2+ ions. Synthesis is carried out in one stage without complicated equipment and is technologically simple. It is determined by thermometric research that the temperature conditions required for the chemical reduction of Ni2+ are achieved due to the heat released during the exothermic reaction of HEMA polymerization in the presence of PVP. With the help of Fourier transform infrared analysis, and thermogravimetric and differential-thermal analysis, the formation of a crosslinked graft copolymer based on HEMA and PVP was confirmed, and its structural parameters, including the efficiency of PVP grafting, PVP content in the copolymer, and the molecular weight of the interstitial fragment of the polymer network, were investigated. The results obtained with scanning electron microscopy revealed that the size of the Ni(0) particles is about 500 nm. X-ray structural analysis of the composites obtained confirmed the existence of metal nickel particles. The strength, elastic, sorption, electrical, and magnetic properties of the obtained composites in the solid (dry) and elastic (swollen) physical states, depending on the composition of the copolymer and the content of the metal filler, have been investigated.

Comparative studies of pure polyvinyl alcohol solutions and compositions based on this alcohol were carried out. The results of research on viscometers of different types — capillary (VTL-2) and ball (Geppler viscometer). The influence of montmorillonite-polyvinylpyrrolidone mixture (MPM) on the dynamic and kinematic viscosity of polyvinyl alcohol solutions was established. It was established that the viscosity of the solution of the composition based on PVA and MPM is 1.3 times higher than the viscosity of the pure polyvinyl alcohol at a concentration of 0.01 g / ml.

Polymerization of hydroxyalkyl(meth)acrylates with polyvinylpyrrolidone has been investigated. Thus highly hydrophilic membranes have been obtained and several properties have been investigated including polymerization rate, viscosity, extinction, water permeability of the membranes, their tensile strength and tensile elongation at break. Parameters characterizing complex formation between monomer and polyvinylpyrrolidone are related to structural parameters of resulting copolymer networks. Effective methods of controlling structures as well as properties of highly hydrophilic membranes have been defined.

We study the influence of concentrations of the components of reactive compositions and the conditions of production and hardening of phenol-formaldehyde resins with the help of epoxy resins in the presence of polyvinylpyrrolidone on the physicomechanical, thermal, adhesion, insulation, and anticorrosion properties of the composites. The positive effect of modifications with polyvinylpyrrolidone and epoxy resin manifests itself within the following ranges of concentrations: 0.5–1 wt.% of polyvinylpyrrolidone and 25–30 wt.% of ED-20 in the presence of 1 wt.% of N, N-dimethylaniline. Thus, the adhesion strength of a glue based on the developed composition becomes four times higher and constitutes 5–6 MPa; the impact strength, static strength in bending, surface hardness, and the specific bulk electric resistance of the specimens hardened at 150–160°C for 25–30 min become 1.5–2.5 times higher and are equal to 5–6J/m2, 15–17 MPa, 350–420 MPa, and (5.5–6.5)⋅1010 Ω⋅m, respectively. The behavior of these characteristics strongly depends on the conditions of hardening. We optimized the composition of modified phenol-formaldehyde resins, which made it possible to produce materials with predicted properties.

Sorption properties of polyvinylpyrrolidone copolymers regarding to different acid-base indicators, as well as heparin and iodine have been investigated. The amount of sorption active centers of synthesized copolymers depends upon synthesis conditions, namely upon temperature and initiator amount, and is determined by the nature of sorbates and copolymers functional groups.

The new conducting polymer hydrogels on the basis of co-polymers of hydroxyethylenemethacrylate and polyvinylpyrrolidone with different nature non-organic fillers have been developed. The dependence of obtained materials electric characteristics on synthesis conditions, quantity and nature of powder filler, moisture content, ambient temperature and magnetic field action have been determined. The possibility of obtaining materials with anisotropic and unidirectional conductivity as well as the wide range of conductivity, which changes with moisture and ambient temperature, has been considered in this work

The proceeding of 2-hydroxyethylmethacrylate grafted polymerization on polyvinylpirrolidone has been examined in the presence of ferrum(II) sulfate. It was observed the formation of crosslinked copolymer capable to be used as a matrix for metal chemical reduction and for metal hydrogel composites obtaining. The effect of Fe structure and concentration on the structural parameters of the polymeric network, copolymers composition, efficiency and degree of grafting has been determined. The interaction between the structure of the synthesized copolymers and their thermal and physicomechanical properties has been established. Кеуwords: copolymerization, copolymer, 2-hydroxyethylmethacrylate, polyvinylpirrolidone, hydrogel, structure.

Modification of polyamide-6 by polyvinyl- pyrrolidone with molecular mass of 12000±2000 has been carried out using their mixing in formic acid solution followed by solvent evaporation. The possibility of films permolecular structure control, physico-mechnical and thermophysical properties by treatment conditions after their formation has been established.