The features of graft polymerization of 1,2-dimethyl-5-vinylpyridinium methyl sulfate to cellulose were established. The possibility of increasing conversion of the monomer in the graft and homopolymerization reaction by adding nonpolymerizable inorganic electrolytes to the solution of the monomer was demonstrated.Fabrication of materials containing quaternary ammonium groups is a promising direction in modification of cellulose fibre materials (CFM). These fibres can be used as chemisorption materials and as the base for creating biologically active materials of different types [1][2][3]. Of the modified CFM with strongly basic properties, CM-A2 fibre, fabricated on the experimental-industrial scale and used in respirators, for separating gold, and for other purposes, has been investigated in the most detail. This material was fabricated with a two-stage periodic method by graft polymerization of a volatile, toxic, waterinsoluble monomer -2-methyl-5-vinylpyridine --to cellulose with subsequent quaternization of the nitrogen atom in the tertiary amino group with epichlorohydrin [4].Synthesis of graft copolymers of cellulose based on the reaction of chain transfer from radicals of the initiator, where diffusion of the initiator into the monomer solution is hindered, is one of the most effective methods of chemical modification of CFM and allows conducting the process according to a one-stage continuous scheme. This method has been used in production of antimicrobial CFM and hemostatic gauze [3,[5][6][7].The characteristics of graft polymerization of 1,2-dimethyl-5-vinylpyridinium methyl sulfate (DMVPMS) to viscose fibre (twist) according to the one-stage continuous method indicated above are described in the present article. An advantage of DMVPMS over 1,2-dimethyl-5-vinylpyridinium is that DMVPMS is not volatile, is soluble in water, and is not very toxic. DMVPMS is manufactured in Russia.For synthesis of the graft copolymer of cellulose and p01y-l,2-dimethyl-5-vinylpyridinium methyl sulfate (C-gr-PDMVPMS), the viscose fibre is treated with an aqueous solution of DMVPMS containing ammonium peroxydisulfate (APS) for several seconds, squeezed (100-200% degree of squeezing), and heated in an oven at 100-140°C or in water vapor medium at 100°C for a certain time. In industrial conditions, the duration of heating the CFM impregnated with a solution of DMVPMS containing APS can be reduced to 1-5 min as a function of the type of equipment [6, 7].The homopolymer and monomer formed as a result of a side reaction and not entering the graft polymerization and homopolymerization reaction were extracted with CFM modified with water. The amount of DMVPMS applied to the CFM (based on the concentration of nitrogen, analyzed on a Hewlett Packard 185B C,H,N-analyzer and spectrophotometrically in aqueous extract at a wavelength of k = 250 nm, the.amount of PDMVPMS grafted to the cellulose (CGP) was determined based on the concentration of nitrogen after extraction of the PDMVPMS homopolymer from the modified CFM not entering in the...