Experimental X-ray diffraction analysis procedures and calculation algorithms are proposed for determining the degree of crystallinity of flax fibres of varied purity and their cellulose component from the integral values of diffraction by the crystallite regions of the analysis sample and the reference standard, which are normalized, taking account of the scattering mass of the preparations. The possibility of determination of the mass cellulose content in flax fibres by X-ray analysis, which dispenses with the need for labor and time consuming chemical analyses, is substantiated.

The comparative research of composition and supramolecular structure of the flax fibers received by methods of a cottonization and a mechanical elementarization under the influence of the cyclic deforming loadings was conducted. It was shown that under the influence of cyclic loadings removal of a considerable part of impurity with the increase in content of cellulose to 80.1% is reached. At the same time, division of complexes onto elementary filament provides the increase in the total surface of material and, as a result, to availability of fibers to the reagents at the subsequent alkaline boiling. X-ray analysis of flax samples with a method of comparison of the normalized parameters of diffraction by crystalline regions of cellulose allowed to establish that degree of crystallinity of a cellulose component of fibers remains constant even at deep purification of raw materials under the influence of cyclic deformations and subsequent boiling. The research of the oriented fibers by X-ray diffraction method has shown that removal of impurity from flax in the course of an elementarization has only weak influence on the sizes of crystallites of cellulose. The increase in the cross sizes of crystallites by 4 – 6% was observed at deep purification of fibers due to the boiling. This phenomenon can be connected with the decrease in influence of a diffraction maximum from impurity on half-width of the equatorial reflex 200 for cellulose Iβ. It should be noted that the longitudinal sizes of crystallites at the same time do not change. It was suggested on possible influence of decrease in content of impurity on supramolecular structure of an amorphous phase of cellulose and as a result on the observed growth of sorption and mechanical properties of flax fibers at an elementarization by method of cyclic deformation.Forcitation:Zavadskii A.E., Stokozenko V.G., Moryganov A.P., Larin I.Yu. Analysis of structural changes of cellulose component in process of elementarization of flax fibers. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 6. P. 102-108.

The possibility of processing of flax fibers using a gas discharge excited in a nitric acid solution for the intensification of lignin degradation processes has been studied. The pulp yield, the degree of polymerization, the lignin content, and the carbohydrate removal rate have been determined. It has been shown that the combination of plasma treatment followed by short-term heat treatment in the acid makes it possible to achieve a high degree of lignin removal. It has been found that the efficiency of the plasma treatment in an acidic medium is higher than that in an alkaline medium.

Bactericidal and antifungal actions of gas discharge initiated in the volume of electrolyte solution on flax fiber placed into the solution were under study. The fiber after plasma-solution treatment and 30 day of storage has no bactericidal properties but showed the partial antifungal activity towards Candida albicans.

An essential part of the processes of refinement of textile materials from natural cellulose fiber is based on redox reactions of the components of process solutions both with admixtures in the fiber and with cellulose. The reducing agents involved in these processes are used in the alkaline treatment of textile materials as antioxidants whose function is to prevent oxidative destruction of cellulose; reducing agents are also introduced into vat or sulfur dye compositions to convert these insoluble dyes into soluble leuco compounds.

On the base of study of reduction properties of systems which are formed at an alkaline treatment of hemp and jute fibers the grouud of combination possibility to single step of process of chemical modification and dyening with sulfur and vat dyes was done.

Chemical transformations of isoeugenol (a model lignin compound) have been investigated under the combined action of an atmospheric pressure discharge initiated in the volume of an electrolyte and alkali treatment using UV spectrophotometric analysis. Plasma-solution activation has been shown to be an initiator of the oxidative breakdown of the aromatic structure of the compound during alkali treatment.

The electric parameters of ¿face¿ underwater discharges were under study. Oscillograms of current and voltage were obtained for various conditions of discharge ignition, and dynamic current-voltage characteristics were obtained. The application of this type of discharge for delignification processes of rough bast fibers (flax, hemp, and jute) in different solutions was investigated. The residual lignin was determined after plasma-solution treatment and after a shorter chemical treatment with reduced alkalinity. Such two-stage treatment was shown to be effective considerably as far as the delignification degree was 68% for flax, 64% for hemp, and 39% for jute, which are higher than those of lignin removal by traditional chemical technologies.

The effect of an atmospheric pressure gas discharge generated inside an electrolyte solution on hemp lignin has been investigated by the methods of IR spectroscopy. It is shown that the gas-discharge activation causes a threefold increase of the lignin solubility with the further chemical treatment. The feasible processes of the interaction of the active particles generated in the electrolyte solution under the discharge action with the lignin macromolecules are considered.

Delignification processes of rough bast fibers under the action of face discharge were studied. The residual lignin content in the fiber and the fiber mass loss were determined after the plasma-solution and subsequent short chemical treatment with reduced alkalinity. This two-stage treatment was shown to be an effective delignification method for bast fibers, since the delignification degree amounts to 68% for flax, 64% for hemp, and 39% for jute fibers.

The expediency of modifying short flax fibre for production of industrial and medical materials was evaluated. The level of transformations in the flax fibres during their modification was demonstrated. The basic trends in the practical implementation of research results were presented.

A correlation is established between the geometric characteristics of natural (cotton, cottonized fibre) and chemical (viscose, polyamide, polyester) fibres with the features of their distribution in blended yarn and the stability of spinning the latter by different methods. Ways of increasing the stability of manufacture of blended yarns containing cottonized fibre are substantiated and their validity is confirmed by the positive results of industrial tests of the yarns at plants in the Ivanovo and Kostroma regions.