Pressure Plasma Surface Treatment Research Articles

Improvement of aerospace thermoplastic composite adhesion to coating with dielectric barrier discharge atmospheric pressure plasma surface treatment

AbstractAtmospheric pressure plasma with dielectric barrier discharge is used to improve the adhesion of novel composite carbon fiber reinforced low melting poly (aryl ether ketone) (CF/LMPAEK) to aerospace coatings under ambient and gas flow (Ar‐O2). The surface activation is evaluated by contact angle measurement and X‐ray photoelectron spectroscopy (XPS). Different atmospheres are used to prevent aging of the treated surface. The water contact angle is considerably reduced after plasma treatment, and the formation of oxygen and nitrogen polar groups is confirmed by XPS analysis. Plasma treatment improves the adhesion of CF/LMPAEK to the topcoat on the primer coating system to the traditional abrasion treatment level. This effect even is intensified with Ar‐O2 plasma. The topcoat alone presents a higher adherence, which provides a reduced coating usage option.

Resin Cement-Zirconia Bond Strengthening by Exposure to Low-Temperature Atmospheric Pressure Multi-Gas Plasma.

The purpose of this study was to investigate the effect of gas species used for low-temperature atmospheric pressure plasma surface treatment, using various gas species and different treatment times, on zirconia surface state and the bond strength between zirconia and dental resin cement. Three groups of zirconia specimens with different surface treatments were prepared as follows: untreated group, alumina sandblasting treatment group, and plasma treatment group. Nitrogen (N2), carbon dioxide (CO2), oxygen (O2), argon (Ar), and air were employed for plasma irradiation. The bond strength between each zirconia specimen and resin cement was compared using a tension test. The effect of the gas species for plasma irradiation on the zirconia surface was investigated using a contact angle meter, an optical interferometer, an X-ray diffractometer, and X-ray photoelectric spectroscopy. Plasma irradiation increased the wettability and decreased the carbon contamination on the zirconia surface, whereas it did not affect the surface topography and crystalline phase. The bond strength varied depending on the gas species and irradiation time. Plasma treatment with N2 gas significantly increased bond strength compared to the untreated group and showed a high bond strength equivalent to that of the sandblasting treatment group. The removal of carbon contamination from the zirconia surface and an increase in the percentage of Zr-O2 on the zirconia surface by plasma irradiation might increase bond strength.

Atmospheric Pressure Plasma Surface Treatment of Polymers and Influence on Cell Cultivation.

Atmospheric plasma treatment is an effective and economical surface treatment technique. The main advantage of this technique is that the bulk properties of the material remain unchanged while the surface properties and biocompatibility are enhanced. Polymers are used in many biomedical applications; such as implants, because of their variable bulk properties. On the other hand, their surface properties are inadequate which demands certain surface treatments including atmospheric pressure plasma treatment. In biomedical applications, surface treatment is important to promote good cell adhesion, proliferation, and growth. This article aim is to give an overview of different atmospheric pressure plasma treatments of polymer surface, and their influence on cell-material interaction with different cell lines.

Enhanced Wetting and Adhesive Properties by Atmospheric Pressure Plasma Surface Treatment Methods and Investigation Processes on the Influencing Parameters on HIPS Polymer

The development of bonding technology and coating technologies require the use of modern materials and topologies for the demanding effect and modification of their wetting properties. For the industry, a process modification process that can be integrated into a process is the atmospheric pressure of air operation plasma surface treatment. This can be classified and evaluated based on the wettability, which has a significant impact on the adhesive force. The aim is to improve the wetting properties and to find the relationship between plasma treatment parameters, wetting, and adhesion. High Impact PolyStyrene (HIPS) was used as an experimental material, and then the plasma treatment can be treated with various adjustable parameters. The effect of plasma parameters on surface roughness, wetting contact angle, and using Fowkes theory of the surface energy have been investigated. Seven different plasma jet treatment distances were tested, combined with 5 scan speeds. Samples with the best plasma parameters were prepared from 25 mm × 25 mm overlapping adhesive joints using acrylic/cyanoacrylate. The possibility of creating a completely hydrophilic surface was achieved, where the untreated wetting edge angle decreased from 88.2° to 0° for distilled water and from 62.7° to 0° in the case of ethylene glycol. The bonding strength of High Impact PolyStyrene was increased by plasma treatment by 297%.

Efficiency enhancement of low-cost metal free dye sensitized solar cells via non-thermal atmospheric pressure plasma surface treatment

Dye sensitized solar cells (DSSC) are an attractive third-generation photovoltaic technology particularly promising for operation under diffuse and lower light conditions. However, high costs of the precious metals used for sensitizing dyes and low charge generation capability parameters limit the utility of DSSCs in comparison to conventional silicon solar cells. In this study, tin oxide (SnO2) photoelectrodes are treated with non-thermal atmospheric pressure plasmas to enhance photovoltaic performance. The effects of nitrogen and argon plasma surface treatment of photoanodes on the efficiency enhancement of DSSCs are systematically investigated by fabricating solar cells using pristine SnO2 and plasma-treated photoanodes. Solar cells made with Eosin Y sensitized pristine SnO2 photoanode exhibited a short circuit current density (JSC) of 1.03 mA cm−2 and an overall power conversion efficiency (PCE) of 0.30% whereas solar cells made with nitrogen plasma treated photoanode exhibited a JSC of 6.20 mA cm−2 and an overall PCE of 1.53% (4 times enhancement) under the same illumination of 100 mW cm−2 (AM 1.5). The efficiency of the solar cells fabricated with Ar plasma treated SnO2 photoanodes also showed an enhanced power conversion efficiency. Further characterizations revealed that the surface plasma treatments increased the surface roughness of the photoanodes. Plasma treatment led to the incorporation of nitrogen species and removal of surface impurities resulting in an increase in dye adsorption in the photoanode and hence the enhancement in the efficiency of the DSSC. This study demonstrated a one-pot treatment method for efficiency enhancement which could be used in various applications such as photovoltaic, catalytic and energy generation applications including DSSCs, thin-film solar cells, perovskite solar cells, gas sensing, bio-sensing, supercapacitors, Li-ion batteries and others.

Increasing the effectivity of the antimicrobial surface of carbon quantum dots-based nanocomposite by atmospheric pressure plasma

Preventing nosocomial infections is one of the most significant challenges in modern medicine. The disinfection of medical facilities and medical devices is crucial in order to prevent the uncontrolled spread of bacteria and viruses. Cost-effective, eco-friendly and fast-acting antibacterial coatings are being developed as the prevention of bacteria and viruses' multiplication on various surfaces. One of the possibilities to create such antimicrobial coatings can rely on a photoactive material, that produces singlet oxygen. However, a remote production of the singlet oxygen and disinfection of the desired surface is a time-consuming process. Hence, a coating material that would autonomously produce singlet oxygen employing ambient light will have a significant impact on the shortening of the disinfection time; leading into an increased number of patients that can be cured in one facility. In this work, an ultra-fast and eco-friendly method for decreasing the disinfection time of the photoactive surface is presented. The atmospheric pressure plasma surface treatment on the hydrophobic carbon quantum dots-polydimethylsiloxane nanocomposite is employed. The plasma-treated samples exhibited improved antibacterial properties compared to non-plasma treated samples, with the best results obtained after only 30 seconds of plasma treatment. The short duration and the scalability potential of the here described method open new possibilities of how to improve the already existing antibacterial coatings.

Antibacterial property of F doped DLC film with plasma treatment

Diamond-like carbon (DLC) has excellent biocompatibility and is attracting attention as a means of surface modification to improve the antibacterial properties of biomaterials used in medical devices. In this study, we examined the correlation between the physical and antibacterial properties of a fluorine-containing DLC (F-DLC) that received an atmospheric pressure plasma surface treatment using oxygen gas (O-F-DLC). The antibacterial effect of O-F-DLC was investigated with the ISO 22196 film adhesion method. As a result, we achieved an antibacterial effect approximately 100 times that of the control sample. These results suggest that O-F-DLC is effective as a surface treatment technology that can provide antibacterial properties.

저온 상압 플라즈마 표면처리 시 power 변화에 따른 RGP렌즈 표면성질 연구

저온 상압 플라즈마 표면처리 시 power 변화에 따른 RGP렌즈 표면성질 연구

Development of Antibacterial Composite Electrospun Chitosan-Coated Polypropylene Materials.

In this study, a natural antibacterial substance chitosan was coated with/without potassium sorbate (KS) (0.8% (w/w) of KS, 8% (w/v) chitosan) onto the polypropylene (PP) film by using electrospinning technique to obtain novel antibacterial composite materials for various applications such as wound dressing, tissue engineering, drug delivery and food packaging. Atmospheric pressure plasma surface treatment was applied onto polypropylene films in order to increase its wettability thus enhancing the adhesion capacity of the films and the optimum CA value was determined as 42.75 ± 0.80°. Scanning Electron Microscope (SEM) and X-ray Photoelectron Spectroscopy (XPS) analyses were realized to observe the morphological changes and chemical properties of the samples, respectively. Contact angle measurements, tensile testing, oxygen and water vapor transmission rate analyses were performed to obtain wettability values, mechanical properties and WVTRs, respectively. The WVTR was increased by plasma treatment and addition of KS (from 14.264 ± 0.214% to 21.020 ± 0.659%). The desired antibacterial performance of the samples was assessed with Staphylococcus aureus and Escherichia coli by inhibition ratio calculation and disc diffusion assay. The highest inhibition ratios were found as 64% for S. aureus and 92% for E. coli for plasma-treated CS-KS-PP films.

Atmospheric Pressure Plasma Surface Treatment of Rayon Flock Synthetic Leather with Tetramethylsilane

This paper investigates the use of atmospheric pressure plasma (APP) treatment for improving the surface hydrophobicity of rayon flock synthetic leather with organosilane precursor (tetramethylsilane (TMS)). Plasma deposition of TMS is regarded as an effective, simple, and low-pollution process. The results show that a highly hydrophobic surface is formulated on the rayon flock synthetic leather. Under a particular combination of treatment parameters, a hydrophobic surface was achieved on the APP-treated sample with a contact angle of 135° while the untreated sample had a contact angle of 0° (i.e., the fabric surface was completely drenched immediately). Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS) confirmed the deposition of organosilane.

An overall assessment of a new adhesive bonding process for composite materials, with regard to quality and cost

An assessment of innovative adhesive bonding process has been performed with regard to quality and cost. In this frame, the effect of two different atmospheric pressure plasma surface treatment conditions on the fracture toughness behaviour of adhesively bonded joints was experimentally investigated. Furthermore, the mechanical performance of a newly developed aerospace structural adhesive has been characterised experimentally in order to assess the quality of the bonded elements. To assess the feasibility of the new process, a complete cost-estimation analysis of the process has been carried out based on the activity-based costing modelling approach, thus serving to the estimation of the total cost/duration of the process. To this end, the newly developed process is assessed with regard to quality and cost. It could be shown that the new process offers tempting alternatives to the existing adhesive bonding and joining processes used in the aeronautic industry.

Effect of adhesive characteristics on static strength of adhesive-bonded aluminum alloys

The use of adhesive is posed to increase dramatically for application to the next generation of vehicle structures as is the use of aluminum. In this study, the effect of adhesive characteristics on the strength of adhesive-bonded lap shear aluminum was investigated. It was found that the joint strength depended on not only the adhesive properties but the bond adhesion between the adhesive and adherend. For the given selected aluminum substrates, to ensure the cohesive failure mode and consistent joint strength it is necessary to select an adhesive which had a weaker than or comparable strength to the bond adhesion. To improve the failure mode from adhesive to cohesive, atmospheric pressure plasma surface treatment of X610-T4PD and X626-T4P aluminum was performed and results showed that it improved not only the joint strength but degree of cohesive failure mode.