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The behavior of colloidal silicon dioxide in a composition with a styrene/butyl acrylate oligomer grafted onto a thermoplastic polyamide adhesive to obtain a branched binder structure with penetration of branches into a capillary-pore system of a reinforcing fiber component is studied. The modifications of disaggregation of SiO2 using ultrasonic treatment and mechanical activation with the impact of high shear stresses, ultrasound, and cavitation are compared. The methods of dynamic light scattering, IR spectroscopy, thermal analysis, and the textile material science are used in experiments to evaluate the elastic-deformation characteristics of fused packets. The set of complementary results confirms that the combined mechanical activation of an aqueous dispersion of oligoacrylate and silica causes destruction of silica nanospheres and the formation of a hybrid oligolymer-inorganic adduct. In contrast to the short-term effects of ultrasonic dispersion of SiO2, consolidated mechanical activation of components solves the problems of preventing aggregation of nanoparticles and providing a uniform distribution of the reinforcing filler in the composite. The efficiency of using the method for regulating the characteristics of the forming units and parts of sewing products has been shown. By selecting oligoacrylate, the separation of the stages of preliminary bonding of the material packets specific to sewing production using a thermoplastic adhesive, the design of a form of a finished product, and its fixing during wet-heat treatment is taken into account. The preparation of a hybrid adduct of mechanical activation provides an optimal ratio of the particle size for the efficient distribution of fractions in interfacial, interfiber, and intrafiber spaces of the textile web. The shift of the peaks of the phase transitions and chemical transformations in a system with nanodispersed SiO2 controlled on the DSC thermograms is consistent with the temperature conditions of successive stages of the engineering process. The possibilities of a controlled change in the characteristics of the forming composite materials and a decrease in the material consumption of sewing products due to grafting modified oligoacrylate with a variable content of silicon dioxide are demonstrated.

Current problems involving the use of flax product waste for obtaining products utilized for the production of cosmetics with sunscreen and antioxidant properties were examined. Ethanol lignin was obtained from flax shives as well as from raw materials subjected to alkaline pulping or biochemical modification. The bioprocessing included a stage of enzymatic degradation of the noncellulose polysaccharides to give aldoses and a stage of isothermal aging at 95°C. Chemical transformations in the polymer were studied by Fourier-transform infrared spectroscopy (FTIR) with resolution of the spectral curve into elementary vibrational bands of the main atomic groups. The spectra were analyzed using the C–C-stretching vibrational band of the aromatic ring at 1510 cm–1 as the internal standard. The enhanced absorption of the hydroxyaryl groups in the spectra of hydrolyzed lignin corresponds to the increase in intensity of the C=C-bond stretching and deformation vibrational bands. The increase in the auxochromic effect of the double bonds adjacent to the aromatic ring is seen in the increase in the absorption in the near-ultraviolet and visible light ranges. The biochemical preparation of the raw material led to disappearance of the IR bands for the double bonds in the carbonyl and alkene groups accompanied by a 1.5–2-fold enhancement of the absorption of alkyl hydroxyl groups and a 3–4-fold enhancement of the absorption of the hydroxyl group in the hydroxyaryl units. These results are consistent with the analytical data obtained upon biomodified preparation by the differential UV spectroscopic method and indicate greater photostabilizing capacity of lignin combined with absolute transparency in the visible range.

The possibility of preparation of hybrid nanocomposites, based on Burdock Arctium Lappa L biomass, modified with enzymes and montmorillonite, was substantiated. It was founded that bio-modification allowing releasing pectin into the biomass Burdock structure that allow fixing clay mineral particles onto biomass. It was found that the increase of pore spaces occurs at the expense of increasing mesopore spaces to 93 %. It allows increasing the adsorption capacity of hybrid nanocomposites to zinc ions and methylene blue to 52.2 and 166.9 mg g-1 respectively; that is 3.5 and 9 times more than adsorption capacityfor initial plant Burdock

The complex influence of sorption of cadmium ions on the state of pectin substances was examined using IR spectroscopy of polymer films according to the change of the absorption bands attributed to the stretching vibrations of С–О bond of carboxylic groups of pectates, deformation vibrations of О–Н bond of secondary hydroxyls, and stretching vibrations of carbonyl in ester groups. The isotherms of Cd2+ adsorption were analyzed at 293–308 K. The sorption process on the samples of pectin isolated from the biomass of burdock Arctium lappa L., rhubarb Rheum, citrus cultures, and model substrates of pectinate, pectate, and pectic acid based on them was adequately described using the Langmuir adsorption model. The thermodynamic parameters of adsorption that quantitatively characterize the binding of cadmium with –СООН groups according to the ionic exchange mechanisms, cationic substitution with –СООСа1/2 groups and coordination interactions with alcohol hydroxyls and carbonyl oxygen of methoxylated galacturonate units were determined.

Lignin preparations were obtained from harsh flax fiber and material exposed to an alkaline solution of sodium borohydride using the Bjerkman extraction method. Peaks of individual vibrations of all types of covalent bonds in the functional groups of the biopolymer were identified. The mechanism of lignin destruction induced by destabilization of the ether bond adjacent to the carbonyl being reduced in the propane link of the macromolecule was confirmed. Reduction of the carbonyl was accompanied by a doubling of the intensity of the absorption band of alkyl hydroxyls and a fourfold increase in the number of hydroxyaryl groups, which was indicative of the accumulation of structural units in the free phenolic form in the system. The dynamics of structural transformations were compared. The duration of serial-parallel processes of polymer reduction and destruction was estimated.

Infrared spectra are obtained for the disperse phase of initial and mechanoactivated hydrosols of colloidal silica and binary systems with an oligoacrylate dispersion (10 wt %). Changes in the absorption bands characterizing the state of the functional groups of the considered substances are analyzed. A conclusion is drawn about interactions that occur according to the mechanism of physical adsorption with silica subjected to ultrasonic dispersion. It is found that the rotor pulse treatment of a hydrosol of silica results in the breaking of siloxane bonds, accompanied by a rise in the concentration of the silanol groups. Mechanoactivation of the binary system ensures processes of chemisorption with the formation of new types of Si–O–C and Si–C bonds.

Polymer-inorganic composites were obtained from montmorillonite and three types of pectin (sugar beet, citrus and nettle). The parameters of particle size, a distance between clay layers and the pore structure and also sorption capacity of composites to ions of Zn (II) and Cu (II) and the methylene blue dye were analyzed. The effect of the chemical structure of pectin to the properties of composite materials was shown.

Pectin-containing substances extracted from flax fiber and commercial preparations of apple and citrus pectins have been modified to obtain model samples of pectic acid, pectinate and pectate. The IR-spectroscopy method has been used to estimate the ratio of galacturonate units with the unsubstituted carboxyl group and those in the methoxylated and calcium pectate forms in the polymer. Correlation ratios have been obtained for describing the dependence between the changes in the state of pectin functional groups, kinetic and thermodynamic parameters of lead cation sorption within the temperature range of 298–318 K. The adsorption process and the equilibrium have been adequately described by the Weber-Morris diffusion model, the pseudo-second order kinetic model and the Langmuir adsorption model. It has been confirmed and quantitatively characterized that lead binding is driven by the mechanisms of ion exchange with COOH groups, cation substitution with COOCa1/2 groups and coordination bonding with OH groups of methoxylated units.

The aim of the study was to improve the range of adhesive interlining materials for clothes to add to the product a complex of improved consumer (shape stability, wear resistance) and special (protective, health-improving) properties. We have found that the modification of the adhesive coating of interlining materials with oligoacrylates provides a transition from the traditional discrete 2D glue interlayers between the bonded materials formation to the highly branched 3D structures of the interfacial layer of composites creation. Using dynamic light scattering method, IR spectroscopy, differential scanning calorimetry, gas adsorption, optical and scanning probe microscopy, methods of textile materials science, we have identified technological approaches that ensure the polymer coating penetration into the intrafiber nanopore spaces of the textile layers. We have identified ways to control the elastic-deformation properties of composites in the modifying the adhesive interlining material process in order to design its properties for the requirements of various garment models. We found a unique possibility of using graftable oligoacrylate dispersion to stabilize the nanodispersed state of functional fillers (silica, nanoferrites) and increase the uniformity of their distribution in the composite structure.

The relationship between the molecular structure characteristics of pectin and the sorption equilibrium with a copper solution was evaluated. The chemisorption processes were described using the model of the theory of micropore volume filling. For pectin samples subjected to a cycle of transformations for changing the chemical state of carboxyl groups in the polymer, the decrease in their activity in passing from the unsubstituted state to the calcium-pectate and methoxylated forms was studied. The contribution of the parameters of the chemical structure of pectins to their total copper adsorption capacity was differentiated. The composition–property models were obtained, which allow one to predict and selectively change the level of the metal-binding capacity of pectin-containing sorbents.

The degree of immobilization of montmorillonite on flax fiber was determined experimentally, and the effect of the nonadditive increase in the sorption capacity of the biocomponent material was evaluated. Studies of pectin–montmorillonite model systems using methods of laser diffraction, X-ray diffraction, and gas adsorption revealed the formation of associate pairs with an equivalent increase in the pectin particle size, a threefold increase in the interlayer distance in the mineral structure, and a superadditive increase in the pore structure parameters. These effects prove formation of hybrid composites with limited intercalation of pectin polymer chains.

The elaborated principles of nanoengineering of linen textile materials implement the techniques of spatially localized effects of protein catalysts on polymeric cellulose companions with selective splitting of impurity compounds without damaging technologically necessary nano-sized formations of binders in the fiber structure. The ranges of optimal values of the residual content in flax fiber prepared for spinning are identified on the basis of the analysis of the successive stages of enzymatic and peroxide treatments contribution to the breakdown of polymers and the differentiation of the influence of impurities on the yarn technological properties. The recommended level of residual pectin, lignin and hemicellulose (wt. %) is: after enzymatic treatment P1 = 1,0±0,1; L1 = 3,9±0,3; Hc1 = 11,0±1,0; after peroxide bleaching P2 = 0,4±0,05; L2 = 2,3±0,3; Hc2 = 7,5±0,5. The required level of fiber structural modification at the stage of preparing roving for spinning can be achieved through use of protein catalysts whose globule size is 50...100 nm. The use of enzymes with these dimensional characteristics helps to ensure breaking of polymer adhesives on the surface of incrusts and in the areas of intercellular formations, which hinder fiber crushing, without damaging nano-sized binding fractions. The implementation of this method contributes to a significant improvement in the uniformity of structural and physical and mechanical properties of flax yarn. Increase in yarn fineness and strength properties of semi-finished products, as well as improvement of deformation properties and reduction of yarn breakages during the spinning processes are achieved.

The concept of nanoengineering of linen textile materials, realizing spatially localized effects of protein catalysts on polymeric cellulose companions and securing selective splitting of impurity compounds with preservation of technologically valuable nanoformations of binders in the fiber structure, is presented. The regulated degree of conversion of polysaccharides with the use of degradation products as secondary reagents for chemical transformations of lignin and polyphenolic compounds leads to the production of materials with new or improved functional and consumer properties.

Concentration and temperature dependences of the redox potentials of neutral and alkaline solutions of glucose, mannose, galactose, galacturonic acid, and xylose were measured. Axial orientation of the secondary hydroxy groups in epimeric hexopyranoses, oxidation of C6 to carboxy group, and the lack of primary hydroxy group in going to aldopentopyranose favor increasing (in the order of listing) destabilization of their cyclic structure, formation of the oxo form, and thermally activated retro-aldol reaction of the latter in alkaline medium. This leads to enhancement of their reducing power and chemical reactivity toward 5,5′,7,7′-tetrabromoindigo.

Changes in the driving force of the multistage interphase transfer of atmospheric oxygen in the presence of a nonionogenic wetting agent and triethanolamine were assessed by using analytical solutions of the film model of mass exchange at the phase boundary to describe the chemisorption uptake of oxygen by a sodium dithionite solution.

Evaluation of the nano sizes of hydrosols from homogeneous cellulosic and industrial products was made using dynamic light scattering method. The influence of the size of the globule of protein catalysts and the duration of their action on the roving of carded flax fiber was compared. The correlation between the change in the equilibrium absorption of sorption marker (methylene blue) and residual content in the fiber of hemicelluloses was monitored. On the basis of a comparative analysis of the efficiency of biocatalysts in industrial homogeneous and cellulosic preparations it was revealed that globule size influences on the efficiency of sorption properties of flax fibers. The use of homogeneous enzymes with differing sized parameters has allowed isolating the contribution of the target enzymatic modification as in the microfibrillar structure of elementary fibers and for modification the hemicelluloses in the binding substance fixing the elementary fibers in the bast bundles (the linen fibrous complexes). The principles of selection of biocatalysts to increase sorption capacity in flax fiber sorbents were revealed. It was found that the sorption capacity of flax fiber sorbents increases due to the development of mezopore space in elementary fibres and regulable amorphization of interfiber binders in the structure of the linen complex. The research revealed that the the amorphization of flax fiber took place only when the cellulases was used. The size of their globules enables the penetration of these enzymes into mesopores of elementary flax fibres. It was established experimentally that the presence of large isoforms of cellulases or hemicellulases can promote as the development of the internal volume into the fibre binders and also conservation the permissible level of reduction of the hemicelluloses amount in flax fibres is not less than 10 mass.%.Forcitation:Aleeva S.V., Lepilova O.V., Kurzanova P.Yu., Koksharov S.A. Specificity of change in sorption capacity of flax fiber under regulable bio-catalytical destruction of neutral carbohydrates. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 2. P. 80-85

It is established that the structure of the hydrophilic part of surfactant molecules affects the solubility of oxygen in alkali solutions: the presence of anionic groups lowers the solvation ability of the system, and the presence of alcoholic hydroxyls raises the sorption capacity of solutions. An original method is proposed for experimental estimation of the concentration of surfactants in alkaline solutions at the gas-liquid interface.

Properties of a 0.0316 mol/l sodium hydroxide solution and the reactivity of reactants involved in the reaction of aerobic oxidation of sodium dithionite are studied over a temperature range of 283–353 K, and changes in motive forces of the rate-limiting, multistage interphase transfer of atmospheric oxygen are estimated. It is established that heating accelerates the adsorption of the gas by the liquid surface by a factor of 18, decreases the solubility of oxygen by a factor of 2, increases the rate of diffusion of oxygen molecules by a factor of 5, and, as a result, increases the absorption of the oxidizer from the air by a factor of 8.

The efficiency of chemical transformations of lignin obtained from Picea excelsa wood under the action of galactose, galacturonic acid and xylose (which can be obtained by enzymatic hydrolysis of hemicelluloses and pectin containing in plant material) was evaluated. The results were compared with use of traditional reducing agent which was borohydride sodium. Using the method of differential UV-spectroscopy was confirmed the increase of a number of phenolic hydroxyl units by Xyl, Gal and GA. The increase of lignin reactivity was controlled to sulfuric acid and to peroxide hydrogen. Similarly to NaBH4, a nucleophilic addition mechanism for the reaction of the reducing saccharides with lignin was revealed. Reduction by NaBH4, Xyl, GA and Gal increased the lignin reactivity to acid solubilisation and to peroxide oxidation.