Surface modification of polycarbonate in homogeneous atmospheric pressure discharge

Abstract

A homogeneous atmospheric pressure dielectric barrier discharge was used for the surface modification of polycarbonate (PC). The discharge was generated between two planar metal electrodes, the top electrode was covered by glass and the bottom electrode was covered by a polymer sample. The discharge burned in pure nitrogen or in a mixture of nitrogen and hydrogen. The surface properties of both treated and untreated polymers were characterized by atomic force microscopy, surface free energy (SFE) measurements and x-ray photoelectron spectroscopy. The influence of the treatment time and power input to the discharge on the surface properties of polymers was studied. The ageing of treated samples was also investigated. The treatment of polymers in the homogeneous atmospheric pressure discharge was homogeneous and the polymer surfaces showed a smaller degree of roughness in comparison with the polymer surfaces treated in a filamentary discharge. The SFE of the treated PC obtained at optimum conditions was 53 mJ m−2 and the corresponding contact angle of water was 38°. The maximum decrease in the SFE during ageing was about 13%. The analysis of the chemical composition showed an increase in the nitrogen concentration in the surface layer, but almost a zero increase in the oxygen concentration. This result was discussed concerning the measured values of the SFE measurement.

Surface modification of the laser sintering standard powder polyamide 12 by plasma treatments

“…As can be clearly seen in Figure a, a dramatic change in the color of the PA12 powder was observed as the pristine PA12 powder is white and becomes light brown after a 1 h exposure, and a darker brown after 2 h. The treated and nontreated powders were also pressed into solid discs with the disc surface displaying a uniform color which reveals that only fewer powder particles were not well‐exposed (see Figure b). Activated atoms and molecules in the electric field during plasma exposure react with the modified surface, creating new oxygenated groups and new chemical functionalities …”

“…Plasma‐ a reactive medium containing free electrons, excited and ionized atoms and molecules, radicals, and metastables and VIS‐UV radiation is widely applied also for chemically modification of polymer surfaces, e.g., ultrafine cleaning, functionalization, etching, or thin film deposition . Atmospheric pressure plasma jets are used to improve the wettability and adhesion, as is low pressure plasma .…”

Investigation of Surface Free Energy for PTFE Polymer by Bipolar Argon Plasma Treatment

“…A good understanding of the surface properties of a solid may be obtained relatively inexpensively from the measurement of the surface free energy. Therefore, the contact angle measurement has been used in the study of surface free energy, wettability and adhesion of low surface energy materials [11,12]. The surface free energy of a solid is an important parameter, playing a vital role in the phenomena that occur at solid-liquid and solid-gas interfaces.…”

Ion energy and angular distributions onto polymer surfaces delivered by dielectric barrier discharge filaments in air: I. Flat surfaces

“…groups on the surface and to some degree due to the etching of the surface. While there have been extensive studies on radicals and UV radiation from atmospheric pressure plasmas (APPs) impinging on polymer surfaces [4][5][6][7], little is known on the range of ion energies incident onto these surfaces that can be produced by APPs.…”