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The authors studied the effect of capacitively coupled radio-frequency (RF) discharge at low pressure on cotton fiber. It is shown that non-cellulose impurities of cotton fiber are removed during processing: the content of extracted substances is reduced by 22-70% depending on the type of solvent when using air, by 5-6% – when using argon. The surface of the fibers becomes hydrophilic, additional submicroscopic pores appear, the roughness increases 1.6 times, water absorption increases 1,5-1,8 times. Discontinuous knitted fabric dyeing was carried out varying the concentration of the active dyes (remasol) in the dye-bath. It was found that the sorption capacity of cotton fibers in relation to the dye increases on average 1.1-1.25 times. To achieve the required color intensity of plasma pre-treated samples dye concentration on average 10-30% less than in the controlled dyeing is needed. The concentrations of dyes that allow obtaining the same intensity of color for the knitted fabric prepared in different ways are selected.

The article discusses the influence of the presence of polyurethane (elastomeric) threads in the composition of a textile material on the effect of plasma modification of hygroscopic properties. The objects of the study were textile (knitted) fabrics based on cotton fibers with the addition of Dorlastan threads. The samples were processed in the plasma of a high-frequency capacitive discharge at a reduced pressure, as the plasma-forming gas was used air. Experiments have shown that the water absorption of the samples after plasma treatment is increased by an average of 1.5 times. The presence of Dorlastan thread does not significantly affect the result of the plasma modification, since the samples are completely immersed in water and the elastomeric threads do not limit the water absorption of its cotton component. The degree of capillary rise, on the contrary, depends on the presence of polyurethane threads. In samples made of 100% cotton, the increase occurs up to 190-. According to these samples, polyurethane threads prevent the capillarity of water by about 4 times. Kinetic curves of water absorption are given. The results suggest that other processing treatments are required to render the polyurethane threads hydrophilicity by plasma treatment. This should be considered in the development of plasma methods for treating textile materials, including in terms of matrix for composite materials.

The article investigates a layer of felt in a complex material, which we intend as rehabilitation footwear element. The complex material consists of layers of rubber and felt, connected with polyurethane adhesive, and we design it for the manufacture of shoe-product sole. The layer of felt inside is in contact with the foot and serves as an insole. The felt was treated with low-temperature plasma (LTP) from the inside of the complex material. It was experimentally obtained the wettability index: for the complex material, containing a treated layer of felt, and a control untreated felt. The research obtained an increase in the hydrophilicity of the LTP-treated felt, which is explained by degreasing the surface, an increase in the porosity of the non-woven material «felt», as well as structural changes in the wool fiber due to plasma treatment. Plasma treatment of woolen felt layer can be recommended to increase the hydrophilicity of the surface and impart antibacterial properties to the inner («insole») surface of the complex material by applying infusions of medicinal plants, etc.

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