Comparison of three dielectric barrier discharges regarding their physical characteristics and influence on the adhesion properties on maple, high density fiberboards and wood plastic composite

Abstract

In this study, three different dielectric barrier discharges, based on the same setup and run with the same power supply, are characterized by emission spectroscopy with regards to the reduced electrical field strength, and the rotational, vibrational and electron temperature. To compare discharges common for the treatment on wood, a coplanar surface barrier discharge, a direct dielectric barrier discharge and a jet system/remote plasma are chosen. To minimize influences due to the setups or power, the discharges are realized with the same electrodes and power supply and normalized to the same power. To evaluate the efficiency of the different discharges and the influence on treated materials, the surface free energy is determined on a maple wood, high density fiberboard and wood plastic composite. The influence is measured depending on the treatment time, with the highest impact in the time of 5 s.

Investigation of biomass surface modification using non-thermal plasma treatment

“…These reactive species increases the surface reactivity, and by reaction with the chemical scavenger the ΔDPPH uptake increases. Similar results have been reported by Peters et al [21], where the surface free energy increased after plasma treatments of 30-90 s, at electron energies of 9.8-12.6 eV (electron temperatures of 76-106.7×10 3 K). In this study, the electron energy is much lower at 6.6 eV (50.6×10 3 K), however the treatment time is significantly longer at 0.5 and 1 h (the procedures for determining the electron energy and temperature are reported elsewhere [22]).…”

“…The syringyl concentrations in the lignin of EFBs have been reported to be higher compared to the other components, such as guaiacyl [1,19] and p-hydroxyphenyl [18]. At a power discharge of 27 W and a power density of 0.95 W cm −2 , the NTP treatment in this study is lower in intensity compared to that of Peters et al [21] (with power densities of 1.6-3.1 W cm −2 ), but as the treatment duration increases from 0 to 1 h, the exposure of the EFB to NTP treatment increases. Therefore, the combination of high syringyl concentration and increase in NTP treatment time resulted in a faster decomposition of syringyl, decreasing the absorbance for the C-H bond for aromatics in syringyl and guaiacyl at 1109 cm −1 (ref.…”

Decrease of the surface pH of maple and the production of nitrate by three pulsed dielectric barrier discharges

“…A physical characterization of the three filamentary dielectric barrier discharges at atmospheric pressure is shown in Peters et al (2017); a summary of the relevant data is in Table 1.…”

“…Plasma treatment of wood is known to lower the water contact angle and increase the wettability, surface free energy and the adhesion strength (Podgorski et al 2000;Aydin and Demirkir 2010;Busnel et al 2010;Acda et al 2012;Viöl et al 2013;Wascher et al 2014a, b;Prégent et al 2015a, b;Altgen et al 2016;Hünnekens et al 2016;Peters et al 2017). During plasma treatment, radical species are placed on the surfaces (Hardy et al 2015) and can replace or increase the effect of sanding (Evans et al 2007;Wolkenhauer et al 2009;Prégent et al 2015b).…”

“…Wood Science and Technology (2018) 52:1495-1510 dielectric barrier discharges are mainly used in the setups as direct volume barrier discharge (Topala and Dumitrascu 2007;Acda et al 2012;Altgen et al 2016;Avramidis et al 2016;Hünnekens et al 2016;Peters et al 2017), coplanar surface barrier discharge (Odrášková et al 2008;Černák et al 2009) and remote plasma (Busnel et al 2010;Riedl et al 2014;Hardy et al 2015;Prégent et al 2015a).…”