Surface modification of nylon 6 by 50 Hz dielectric barrier discharge Produced in air and argon at atmospheric pressure

This paper reports the use of dielectric barrier discharge (15.65 kV, 50 Hz) produced in an air and argon environment at atmospheric pressure to modify the surface of Nylon 6. Power dissipation in air and argon DBD was determined to be 14.60 W and 12.00 W, respectively. Similarly, the average density and temperature of an electron in air DBD were found to be 1.74 ×1011 cm-3 and 1.31 eV, respectively, while the values were 2.50 ×1011 cm-3 and 0.68 eV in argon DBD. The water contact angle (WCA) was measured to confirm the enhancement in wettability. On treating the sample with air DBD for 15 minutes, the contact angle reduced from 134.07° ± 3.20° to 89.11° ± 3.06° while it was reduced to 82.74° ± 4.20° within 1 minute using argon. The study found that treating a hydrophobic sample of Nylon 6 with DBD for a certain period of time transformed it into a hydrophilic one, and extending the treatment time further enhanced its wettability. The use of argon DBD was found to be more effective than air DBD in altering the surface properties of the sample, as the sample became hydrophilic after only one minute of treatment with argon DBD and completely wettable after three minutes. The findings suggest that air and argon DBD have potential applications in modifying the surface properties of Nylon 6, which could have practical implications in the production of textiles, membranes, and other materials

Surface modification of nylon 6 by 50 Hz dielectric barrier discharge Produced in air and argon at atmospheric pressure

This paper reports the use of dielectric barrier discharge (15.65 kV, 50 Hz) produced in an air and argon environment at atmospheric pressure to modify the surface of Nylon 6. Power dissipation in air and argon DBD was determined to be 14.60 W and 12.00 W, respectively. Similarly, the average density and temperature of an electron in air DBD were found to be 1.74 ×1011 cm-3 and 1.31 eV, respectively, while the values were 2.50 ×1011 cm-3 and 0.68 eV in argon DBD. The water contact angle (WCA) was measured to confirm the enhancement in wettability. On treating the sample with air DBD for 15 minutes, the contact angle reduced from 134.07° ± 3.20° to 89.11° ± 3.06° while it was reduced to 82.74° ± 4.20° within 1 minute using argon. The study found that treating a hydrophobic sample of Nylon 6 with DBD for a certain period of time transformed it into a hydrophilic one, and extending the treatment time further enhanced its wettability. The use of argon DBD was found to be more effective than air DBD in altering the surface properties of the sample, as the sample became hydrophilic after only one minute of treatment with argon DBD and completely wettable after three minutes. The findings suggest that air and argon DBD have potential applications in modifying the surface properties of Nylon 6, which could have practical implications in the production of textiles, membranes, and other materials

Surface modification of polyamide by 50 Hz dielectric barrier discharge (DBD) produced in air at atmospheric pressure

Industrial applications of the dielectric barrier discharge (DBD) have a long tradition. However, lack of understanding in some of its fundamental issues, such as stochastic behaviors, is still a challenge for DBD researchers. The work was carried out at line frequency, 15 kV, and at atmospheric pressure. This work focuses on the study of the electrical and optical characteristics of DBD at atmospheric pressure to determine a suitable condition for utilization of the device for surface modification of polyamides (PA) (Nylon 6/6). In this work, films were treated by dielectric barrier discharge and the effects on the morphology and chemistry of the material were studied. Surface characteristics were examined via contact angle measurements and SEM. The wettability tests revealed the improvement of the hydrophilic character of the surface of polyamide films as the water contact angle measured after the plasma treatments significantly decreased. The corresponding changes of the total surface energy revealed a significant increase in its polar component. The improvement of the wettability of PA strongly depends on the treatment time. The outcomes of the experiments proved that the modification of surface properties via plasma treatment reach its saturation point after a certain treatment time thus reducing the necessity of further treatment. BIBECHANA 18 (1) (2021) 19-2

Surface modification of polyamide by 50 Hz dielectric barrier discharge (DBD) produced in air at atmospheric pressure

Industrial applications of the dielectric barrier discharge (DBD) have a long tradition. However, lack of understanding in some of its fundamental issues, such as stochastic behaviors, is still a challenge for DBD researchers. The work was carried out at line frequency, 15 kV, and at atmospheric pressure. This work focuses on the study of the electrical and optical characteristics of DBD at atmospheric pressure to determine a suitable condition for utilization of the device for surface modification of polyamides (PA) (Nylon 6/6). In this work, films were treated by dielectric barrier discharge and the effects on the morphology and chemistry of the material were studied. Surface characteristics were examined via contact angle measurements and SEM. The wettability tests revealed the improvement of the hydrophilic character of the surface of polyamide films as the water contact angle measured after the plasma treatments significantly decreased. The corresponding changes of the total surface energy revealed a significant increase in its polar component. The improvement of the wettability of PA strongly depends on the treatment time. The outcomes of the experiments proved that the modification of surface properties via plasma treatment reach its saturation point after a certain treatment time thus reducing the necessity of further treatment. BIBECHANA 18 (1) (2021) 19-2

Surface modification of polymers by 50 Hz dielectric barrier discharge (DBD) plasma produced in air at 40 Torr

This study deals with the surface modification of polymer films utilizing a custom designed cost- effective dielectric barrier discharge (DBD) plasma produced in air at reduced pressure. We comprehensively examine diverse aspects of surface modification, encompassing electrical discharge characterization, optical signal analysis, contact angle measurements, and surface morphology assessment. Our observations unveiled the presence of distinctive filamentary streamer-based micro-discharges during the DBD process, with a power consumption of approximately 5.64 W and an electron density of 3.4 × 1011 cm−3. Optical emission spectroscopy identifies multiple emission peaks attributed to nitrogen emissions. Notably, plasma treatment substantially reduced the water contact angle and augmented surface energy on polypropylene (PP) and polyethylene terephthalate (PET) films. Surface morphology analysis illustrated an increase in surface roughness following plasma treatment. Intriguingly, the initial rapid alterations in wettability and surface morphology attained equilibrium after approximately 30 s of treatment. This study highlights atmospheric DBD plasma's effectiveness in customizing polymer surfaces, improving wettability and roughness, offering promising applications for enhanced adhesion and wetting

Surface Treatment of Handmade Lokta Paper by Atmospheric Pressure Dielectric Barrier Discharge Using 50 Hz Line Frequency

The discharge was generated between two rectangular parallel-plate copper electrodes using a sinusoidal voltage of 12.8 kV (rms) of frequency 50 Hz and characterized using electrical and optical measurements. The effects of the discharge on the wicking property and weight loss of Lokta paper were studied respectively by the wicking test and gravimetric method. The estimated value of electron density and electron temperature in the discharge were 8.47×108 cm-3 and 1.29 eV. The results showed a significant improvement in water absorption ability and considerable weight loss (%) in Lokta paper after the plasma treatment

Experimental Studies on Physicochemical Parameters of Water Samples before and after Treatment with a Cold Atmospheric Plasma Jet and its Optical Characterization

Cold plasma-liquid interaction becomes a growing interdisciplinary area of research involving plasma physics, fluid science, and chemistry. Plasma-liquid interaction has gained more interest over the last many years due to its potential applications in different fields. Cold atmospheric plasma jet is an emerging technology for surface drinking water treatment to improve quality and surface modification that is chemical-free and eco-friendly. Cold plasma treatment of water samples results in changes in turbidity, pH, and conductivity and in the formation of reactive oxygen and nitrogen species (RONS). As a result, plasma-activated water has a different chemical composition than water and can serve as an alternative technique for microbial disinfection. CAPJ has been generated by a high voltage 5 kV and a high frequency 19.56 kHz power supply. The discharge has been characterized by an optical method. To characterize the cold atmospheric pressure argon plasma jet, discharge plume temperature, and electron rotational and vibrational temperature have been determined. Cold atmospheric argon plasma jet produced at atmospheric condition contains high energetic electrons, ions, UV radiation, reactive oxygen, and nitrogen species named as cold plasma which has a wide range of applications in the biomedical industry, as well as in water treatment. Nowadays, researches have been carried out on ozonation through plasma jet interaction with surface drinking water. In this paper, we compare the change in physical and chemical parameters of surface water used for drinking purposes. The significant change in the physical parameters such as pH, turbidity, and electrical conductivity was studied. In addition, the significant changes in the concentration and absorbance of nitrate, ferrous, and chromium ions with respect to treatment time were studied. Our results showed that plasma jet interaction with surface drinking water samples can be useful for the improvement of water quality and an indicator for which reactive species play an important role in plasma sterilization