Study of copper sulfide layers on a polyamide film formed by the use of higher polythionic acids

CuxS layers on polyamide obtained by a sorption-diffusion method have been studied. These layers are formed when ions of higher polythionates and sulfur sorbed into polyamide react with a solution of Cu(I–II) salt. By potentiometric studies it has been determined that x varies in the interval 1< x < 2 in electrically conductive or semiconductive copper sulfide layers. The composition of the CuxS layer changes more significantly during the first 30 days in the direction of x decreasing. X-ray diffraction studies of the CuxS layers revealed six phases: with x = 2 (chalcocite), x = 1.9375 (djurleite), x = 1.75 (anilite), x = 1.12 (yarrowite), x = 1.06 (talnakhite), and x = 1 (covellite). The phase composition of the CuxS layer depends on the period of keeping in Cu(I–II) salt solution and on the sulfur concentration in the polyamide. Key words: polyamide; polythionic acid; sulfurisation; layer of copper sulfide 1