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Mesophasogenic solvents in the vapor state actively affect the structure of cellulose acetates of different morphological forms (fibre, film, bulk polymer). On the supramolecular level, this is manifested by initiation of orientation processes and on the conformational level by a change in the optical density, up to a change in the direction of rotation of the cholesteric helix to the opposite direction. The approach found creates conditions for formation of a given structure and three-dimensional organization of the polymer matrix for manufacture of materials with improved properties and new qualities.Of the large number of polysaccharides, cellulose and cellulose derivatives are the most important in the total production volume of polymeric materials for industrial and domestic applications. This class of macromolecular compounds has been actively studied up to now both to obtain fundamental knowledge and for their practical use.Domestic scientists specializing in polymer science have made an enormous contribution to the study of the structure, composition, and properties of cellulose and its ethers. They include the internationally known scientists

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This paper presents the results of our study of the diffusion front progression of OH − ions in the bulk of a flat layer of the salt chitosan form during the course of the chemical reaction of the polymer-analogous salt → base transformation, accompanied by the formation of a water-insoluble polymeric phase as a gel film with its structure of concentric rings or tangential bands. Using scanning electron microscopy and polarization microscopy, structural and morphological features of these periodic formations were visualized. Physicochemical parameters and spatiotemporal mass transfer characteristics were obtained. The process under study is shown to obey the classical laws of ion-exchange reactions, and the formation kinetics and the ratio of the positions of periodic structures are described by the laws characteristic of the Liesegang phenomenon. The average diffusion coefficients of hydroxide ions in the periodic formations calculated, considering the protonation degree of amino groups, were found to be no more than a decimal order of magnitude lower than those in an aqueous solution. This confirms the fact of swelling of the formed chitosan base and the existence of a gel film, in whose liquid phase diffusion occurs.