The kinetic and thermodynamic parameters of polymer-analog conversion of the graft copolymer of polycaproamide and polyglycidyl methacrylate with sulfamic acid (initial rate, duration, and effective activation energy) were determined. It was shown that the values of the initial rates correlate well with the concentration of the sulfamic acid reaction solution. The formation of a new derivative of the PCA-PGMA graft copolymer containing functionally active amino and sulfo acid groups was confirmed by the data from chemical and analytical analysis and IR spectroscopy. A method was developed for obtaining a sorption-active fibrous polyampholyte containing functionally active amino and sulfo acid groups with SEC HCl = SEC NaOH = 0.895 mmole/g.The wide use of sorption processes, including use of chemisorption fibres characterized by high sorption rates and preservation of the strength properties in repeated regeneration, is one direction in comprehensively solving environmental problems [1][2][3][4].The characteristics of synthesis of polycaproamide copolymer derivatives with sulfamic acid, whose functional groups are capable of donor-acceptor and ion-exchange reactions with heavy metal ions, were investigated here to obtain fibrous polyampholytes of new composite composition.Selection of the method of obtaining polyfunctional compounds based on graft polymerization of nonionogenic monomers followed by polymer-analog conversion of the graft chains was predetermined by its high processability among existing processes [2]. We investigated polycaproamide fibre modified by grafting polyglycidyl methacrylate, the graft copolymer of polycaproamide and polyglycidyl methacrylate (PCA-PGMA) in the ratio of 56:44.The PCA fibre was modified in the experimental conditions in a setup with forced circulation of the reaction emulsion containing glycidyl methacrylate, a nonionogenic surfactant, and the components of a redox system through a layer of the fibre tightly packed in the perforated cylinder of the apparatus. Due to the high conversion of glycidyl methacrylate (98-99%) and the grafting efficiency (99%), the process for obtaining these graft copolymers can be assigned to zero-waste technologies.The polymer-analog conversion of the PCA-PGMA graft copolymer was conducted with a functionally active modifier -sulfamic acid -in heterogeneous conditions by treating the graft copolymer with aqueous solutions at a hydromodulus of 30 ml/g. Since sulfamic acid is limitedly soluble in water, the sulfamic acid solutions with a concentration of 1 to 4 M were obtained by dissolving it at 60-80°C. Due to possible crystallization of sulfamic acid, the reaction products were repeatedly washed off with hot water (80-90°C) to remove the unreacted acid. The occurrence of the reaction of the PCA-PGMA graft copolymer with the sulfamic acid was judged by the content of titrimetrically determined nitrogen and SO 3 H groups in the products of the polymer-analog conversions and the IR spectroscopic data.Moscow State Textile University.