Underwater pulse electrical diaphragm discharges for surface treatment of fibrous polymeric materials

Preliminary results on physical characteristics of pulsed underwater diaphragm electrical discharges are presented. The discharges burning in tap water, water-chelaton solutions, and some other water-based solutions were studied as a potential atmospheric-pressure H2O-plasma source for surface activation of polyester cord threads. The discharge plasma parameters have been measured by means of optical emission spectroscopy. Electron number density of roughly 2 x 10(8) cm(-3) and an electron temperature of 1x10(4) K were estimated from broadening of hydrogen lines (Halpha), and vibrational temperature of 2500 K was determined from the vibrational band of nitrogen. A significant increase in the surface energy and wettability of the cord threads due to the plasma treatment was obtained.