Correlation of surface hydrophilicity and surface static properties in epoxy/glass fibre after plasma treatment

Abstract

In this study, which was performed to identify a degradation mechanism in macromolecular insulating material, the contact angle, surface potential decay, surface resistance rate and XPS analysis were compared after exposure of fibre-glass-reinforced polymer (FRP) laminate to plasma discharge.In the case of the contact angle, the surface of the untreated specimen showed weak hydrophobicity at 73• . However, the contact angle was decreased to 20• in the plasma-treated specimen. In the case of chemical changes arising from plasma treatment, carboxyl radicals were generated mainly in the plasmatreated surface, which was rapidly changed to a hydrophilic surface. In the corona potential decay study to determine the electrical changes of the surface, positive charges were decreased rapidly when compared with negative charges, leading to a negative surface for the untreated specimen. However, in the case of the hydrophilic surface, a lot of carboxyl radicals (-COO) acting as positive polarity were generated, resulting in a positive surface. Owing to such a positive surface, the charges of applied negative polarity were decreased rapidly.

Balancing charge dissipation and generation: mechanisms and strategies for achieving steady-state charge of contact electrification at interfaces of matter

“…These reactions cause the formation of hydrophilic functional groups on the surface for increasing conductivity. [185][186][187] Because of the complexity of the surface, it has been challenging to model the rate of charge dissipation by surface conduction. A very simple model is based on the same principles used for deriving the expression for the rate of charge dissipation by bulk conduction, except that the ground is provided at the lateral edge of the surface.…”

Effect of chemical corrosion on charge transport behaviour in epoxy/Al 2 O 3 nanocomposite irradiated by gamma ray

“…To study further the effect of corrosion, a high-resolution analysis of the C1s and the O1s has been carried out. Figure 1a shows the C1s characteristic spectrum of the uncorroded ER sample, which is mainly composed of five main components, that is, C-C and C-H bonds at a binding energy of 284.49 eV [23], C-N bond at 285.6 eV [23], C-O bond (C-OH, C-O-C) at 286.3 eV [23,24], C=O bond (NH-C=O) at 287.7 eV [21] and HO-C=O bond at 288.7 eV [24]. Figure 1b shows the O1s characteristic spectrum, which is mainly composed of two peaks, that is, O=C bond (NH-C=O and OH-C=O) at 531.5 eV [24]and O-C bond (C-OH and C-O-C) at 532.6 eV [21].…”

Investigation of the postcure reaction and surface energy of epoxy resins using time‐of‐flight secondary ion mass spectrometry and contact‐angle measurements

“…The second approach is an equation‐of‐state formula and is reported so that the surface energy can be calculated with only one contact‐angle measurement 9–12. There has been previous research on the correlation between the surface properties and molecular characteristics of epoxy and phenolic resins 6, 13–16. The surface polarity as a result of the presence of different functional groups is related to the overall surface energy 13.…”

“…There has been previous research on the correlation between the surface properties and molecular characteristics of epoxy and phenolic resins 6, 13–16. The surface polarity as a result of the presence of different functional groups is related to the overall surface energy 13. Lim et al13 reported that an increase in surface hydrophilic properties after the plasma treatment of a glass‐fiber epoxy resin composite resulted from changes in the surface composition and specifically from a decrease in the relative concentration of carbon and an increase in the relative concentration of oxygen on the surface as measured by X‐ray photoelectron spectroscopy.…”

“…The surface polarity as a result of the presence of different functional groups is related to the overall surface energy 13. Lim et al13 reported that an increase in surface hydrophilic properties after the plasma treatment of a glass‐fiber epoxy resin composite resulted from changes in the surface composition and specifically from a decrease in the relative concentration of carbon and an increase in the relative concentration of oxygen on the surface as measured by X‐ray photoelectron spectroscopy. They explained that the high oxygen content on the surface was a result of the increased presence of carbonyl groups originating from reactions at the treated surface with oxygen and oxygen‐containing molecules from the surrounding air.…”