We have found that SO2 plasma is a very good emitter of UV radiation as well as radiation in the blue part of the emission spectrum which is due to excited SO molecules. Optical emission spectroscopy was used to characterize SO2 plasma during transition from capacitively coupled discharge (E-mode) to inductively coupled discharge (H-mode). For E-mode a huge continuum between 200 and 500 nm was found in the emission spectrum as well as minor atomic oxygen lines. During transition to H-mode the intensity of the continuum has remarkably decreased, while the intensity of atomic oxygen lines has greatly increased, which indicates that a strong dissociation of SO2 and SO molecules appeared.
COBISS.SI-ID: 27891239
In this paper we report about the results of surface treatment of PET polymer in SO2 and H2S plasma. These results are compared with the results obtained by treatment of the same polymer in the plasma generated in the standard gases that are commonly used for modification of polymers like oxygen, CO2, nitrogen, hydrogen, argon etc. Surface changes were investigated by different methods including XPS, AFM and wettability measurements. We have found significant changes in the chemical composition of plasma treated samples, as well as morphological changes of the surface and its wettability. As expected, we get in the case of sulphur-containing plasmas sulphur groups on the surface: -SH2 in the case of H2S plasma and –SOx in the case of SO2 plasma. In the case of SO2 plasma, also surface oxidation appears, which is due to dissociation of SO2 molecules to oxygen atoms that react with the surface.
COBISS.SI-ID: 28240423