Effect Of Plasma Surface Treatment Research Articles

Exploring effects of plasma surface engineering on cellulose nanofilms via broadband THz spectroscopy

For the extended ultra-wideband THz band up to 10 THz and beyond, materials with different functional properties are required. In addition, the THz shielding devices require the desired thickness for different shielding effects, which can be tailored by the surface functionalities. Here, a plasma-assisted soft chemistry approach was used to tailor the cellulose nanofibrils (CNFs), and the effects of plasma surface treatment were investigated using non-destructive terahertz time-domain spectroscopy (THz-TDS). CNFs with three different thicknesses were investigated as a function of mild and strong plasma treatment. The ultra-broadband THz-TDS evaluation of CNF films overcomes the challenge by surpassing the conventional low-frequency THz-TDS measurements and reveals many characteristic THz features of CNF at 2.1, 3.1, 5.1, 7.0, 10.3 and 10.9 THz. THz-TDS analysis indicates thinning of CNF after plasma treatment due to the plasma etching effect. At the same time, the microcrystalline properties of the CNF samples remain intact even after significant surface modification under plasma carbonisation conditions. Apart from this, the studies proposed the required minimum thickness for THz shielding applications based on the optical parameters and THz properties derived from the plasma-treated CNF structures, which could be used to define the thickness of sustainable shielding materials for THz devices.

Effects of plasma surface treatment on the bond strength of zirconia with an adhesive resin luting agent.

The purpose of this study was to evaluate the effect of the atmospheric pressure plasma treatment as a surface treatment method on the contact angle and shear bond strength (SBS) of zirconia ceramics and the failure mode between the self-adhesive resin luting agent and zirconia. The zirconia specimens were divided into eight groups based on the surface treatment method: alumina blasting, air plasma, argon plasma (AP), Katana cleaner, ozonated water, ozonated water+AP, Katana cleaner+AP, and tap water+AP. The contact angles, SBS, and fracture modes were tested. AP treatment significantly reduced the contact angle (p<0.0001). The combination of AP and other cleaning methods showed a higher bond strength and more mixed fractures. Our findings indicate that using atmospheric pressure plasma with argon gas, combined with other cleaning methods, results in a stronger bond than when using alumina blasting alone.

Bone-to-Implant Contact in Implants with Plasma-Treated Nanostructured Calcium-Incorporated Surface (XPEEDActive) Compared to Non-Plasma-Treated Implants (XPEED): A Human Histologic Study at 4 Weeks

Titanium implants undergo an aging process through surface hydrocarbon deposition, resulting in decreased wettability and bioactivity. Plasma treatment was shown to significantly reduce surface hydrocarbons, thus improving implant hydrophilicity and enhancing the osseointegration process. This study investigates the effect of plasma surface treatment on bone-to-implant contact (BIC) of implants presenting a nanostructured calcium-incorporated surface (XPEED®). Following a Randomized Controlled Trial (RCT) design, patients undergoing implant surgery in the posterior maxilla received additional plasma-treated (n = 7) or -untreated (n = 5) 3.5 × 8 mm implants that were retrieved after a 4-week healing period for histological examination. Histomorphometric analysis showed that plasma-treated implants exhibited a 38.7% BIC rate compared to 22.4% of untreated implants (p = 0.002), indicating enhanced osseointegration potential. Histological images also revealed increased bone formation and active osteoblastic activity around plasma-treated implants when compared to untreated specimens. The findings suggest that plasma treatment improves surface hydrophilicity and biological response, facilitating early bone formation around titanium implants. This study underscores the importance of surface modifications in optimizing implant integration and supports the use of plasma treatment to enhance osseointegration, thereby improving clinical outcomes in implant dentistry and offering benefits for immediate and early loading protocols, particularly in soft bone conditions.

Investigating the thermal effects of plasma surface treatment on crystallinity and mechanical behavior of PEEK

This study investigates the influence of plasma surface treatment on the local crystallinity and its impact on the local and global mechanical properties of PEEK samples. Local degree of crystallinity is assessed using Raman spectroscopy, while nanoindentation measurements are employed to examine the nanoscale mechanical properties for commercial, raw injected, annealed, and plasma-treated PEEK samples. The results reveal a significant correlation between the local degree of crystallinity and the nanoscale mechanical properties within the PEEK cross-section. Scanning Electron Microscopy (SEM) observations further support these findings by illustrating the density and evolution of spherulitic structures within the PEEK cross-section. Tensile mechanical tests are conducted to evaluate the influence of crystallinity variation on overall behavior. The results demonstrate that even localized variations in crystallinity can affect the overall mechanical response of PEEK samples. These findings enhance our understanding of the relationship between crystallinity, mechanical properties, and surface treatment on PEEK, providing valuable insights for optimizing its performance in various applications.

Effect of plasma surface treatment of three different CAD/CAM materials on the micro shear bond strength with resin cement (A comparative in vitro study)

ObjectivesThis study aimed to evaluate and compare the effect of plasma treatment versus conventional treatment on the micro shear bond strength (μSBS), surface roughness, and wettability of three different CAD/CAM materials. Materials and methodsSixty cylindrical specimens (5 mm diameter × 3 mm height) were prepared from three different CAD/CAM materials: Group A: Zirconia, Group B: Lithium disilicate, and Group C: Resin nano-ceramic. Each group was subdivided into two subgroups according to surface treatment used: Subgroup I: Conventional treatment, zirconia was sandblasted with Al2O3, while lithium disilicate and resin nano-ceramic were etched with hydrofluoric acid. Subgroup II: Plasma treatment, the surface of each material was treated with a plasma device (PiezoBrush® PZ3 Handheld Device, Relyon Plasma, Regensburg, Germany). G-Multi PRIMER was applied, then self-adhesive cement (G-CEM ONE) was applied using a split mold (1 mm diameter × 3 mm height), and μSBS was tested in a universal testing machine. The surface roughness was measured using a profilometer. Nine additional specimens of each material for wettability test using an optical tensiometer. Statistical analysisThe data were analyzed using ANOVA and Bonferroni test at a level of significance of 0.05. ResultsThe highest mean of μSBS was recorded by AII (27.3 MPa), while the lowest was recorded by AI (17.9 MPa). One-way ANOVA test revealed a significant difference among groups. Bonferroni test showed each two subgroups significant difference except subgroups AI, CI and BII, CII, where there was a non-significant difference. For all CAD/CAM materials, conventional treatment increased the surface roughness compared to plasma treatment, while the contact angle decreased after plasma treatment. ConclusionPlasma treatment increased the μSBS of resin cement to zirconia significantly while not significantly affecting the μSBS of resin nano-ceramic. Conventional treatment of lithium disilicate provided significantly higher μSBS than plasma treatment.

In vitro study of the antibacterial effect of plasma surface treatment using Argon gas on orthodontic stainless steel brackets against Streptococcus mutans and Lactobacillus acidophilus

Orthodontic treatment improves dental aesthetics. However, the prolonged duration of treatment and patient's oral hygiene results in more significant biofilm buildup and boosting concentrations of acidogenic bacteria, resulting in enamel demineralization. Plasma treatment technology has developed an interest in enhancing appliances' surface properties. The present study aimed to investigate cytotoxicity and antibacterial activity represented by anti-adhesion and anti-biofilm formation of Argon plasma treatment on orthodontic brackets against Streptococcus mutans and Lactobacillus acidophilus and evaluation the effect of change in plasma exposure duration on these properties in vitro. The study included three groups, group 1: untreated stainless steel brackets, group 2: brackets treated for 15 min, and group 3: brackets treated for 30 min. S.mutans and L.acidophilus were isolated from patients undergoing fixed orthodontic treatment. Microbiological tests included adhesion assay using plate counting method and biofilm formation assay using ELISA plate reader. S. mutans&amp; L. acidophilus were cultivated in three groups, and their adherence and biofilm formation were measured and compared. The biocompatibility of treated stainless steel brackets was evaluated by MTT assay. Results showed that groups 2 &amp; 3 had better anti-adhesion and anti-biofilm activity when compared with group 1, with a significant difference between group 1 &amp;group 3, in which group 3 recorded the lowest biofilm formation and the highest anti- anti-A adhesion activity. MTT showed that groups 2 and 3 exhibited more than 80% cell viability after 24, 48, and 72 hours. Plasma surface treatment of metal brackets possesses antibacterial activity against S.mutans and L.acidophilus; alteration exposure time impacts the development of these properties. Keywords. Plasma treatment, Argon gas, orthodontic brackets, biofilm, antimicrobial.

Enhancement of Adhesive Bonding Properties of Polyetheretherketone-based Materials using Plasma Surface Modifications.

To investigate the effects of plasma surface treatments and methyl methacrylate-based adhesives on polyetheretherketone. One hundred ten polyetheretherketone specimens were fabricated and divided into five pretreatment groups: group ArP, 100% argon plasma; group ArOP, 50% argon + 50% oxygen plasma; group ArNP, 50% argon + 50% nitrogen plasma; group ArONP, 75% argon + 12.5% oxygen + 12.5% nitrogen plasma; group C, control. Atomic force microscopy and scanning electron microscopy were performed after surface treatments. After topographical surface examinations, Visio.link primer (Bredent) (n = 10) was applied to the surface of half of the samples in each group (n = 20) and the veneering resin was polymerized onto the polyetheretherketone. The shear bond strengths were measured using a universal test machine. The mean bond strengths of the Visio.link primer applied to group ArP and group ArONP (13.9 and 13.6 MPa, respectively) were statistically significantly higher than that of group C (9.0 MPa). The average shear bond strength of the Visio.link subgroups was higher than that of the Visio.link subgroups (p > 0.05). The use of a methyl methacrylate-based adhesive (Visiolink) provides bonding between polyetheretherketone-veneering composites. Different plasma treatments without primer application had no significant effect on bonding.

A Study of the Effects of Plasma Surface Treatment on Lipid Bilayers Self-Spreading on a Polydimethylsiloxane Substrate under Different Treatment Times.

Plasma-treated poly(dimethylsiloxane) (PDMS)-supported lipid bilayers are used as functional tools for studying cell membrane properties and as platforms for biotechnology applications. Self-spreading is a versatile method for forming lipid bilayers. However, few studies have focused on the effect of plasma treatment on self-spreading lipid bilayer formation. In this paper, we performed lipid bilayer self-spreading on a PDMS surface with different treatment times. Surface characterization of PDMS treated with different treatment times is evaluated by AFM and SEM, and the effects of plasma treatment of the PDMS surface on lipid bilayer self-spreading behavior is investigated by confocal microscopy. The front-edge velocity of lipid bilayers increases with the plasma treatment time. By theoretical analyses with the extended-DLVO modeling, we find that the most likely cause of the velocity change is the hydration repulsion energy between the PDMS surface and lipid bilayers. Moreover, the growth behavior of membrane lobes on the underlying self-spreading lipid bilayer was affected by topography changes in the PDMS surface resulting from plasma treatment. Our findings suggest that the growth of self-spreading lipid bilayers can be controlled by changing the plasma treatment time.

Effect of Plasma Surface Treatment on Shear Bond Strength with Denture Base Resin in Co-Cr Alloy, Ti-6Al-4V Alloy, and CP-Ti Alloy.

The purpose of this study was to examine the effect of plasma treatment by treating the surface of Co-Cr alloy, Ti-6Al-4V alloy, and CP-Ti alloy as a material for denture metal frameworks with non-thermal atmospheric pressure plasma (NTAPP) and measuring their shear bond strength (SBS) with a heat-cured resin. 20 specimens were prepared for each of Co-Cr, Ti-6Al-4V, and CP-Ti alloys. Each metal alloy group was divided into the following subgroups depending on NTAPP treatment: C (Co-Cr alloy without plasma), T (CP-Ti without plasma), A (Ti-6Al-4V alloy without plasma), CP (Co-Cr alloy with plasma), TP (CP-Ti with plasma) and AP (Ti-6Al-4V alloy with plasma). Specimens were treated with a metal conditioner and bonded to a denture base resin. SBS was measured using a universal testing machine. All data obtained were statistically analyzed using two-way analysis of variance (ANOVA), Tukey's honestly significant difference (HSD) test, and independent t-test. The mean values (SD) of SBS (MPa) were: 10.31 (1.19) for C group; 12.43 (0.98) for T group; 13.75 (2.02) for A group; 13.53 (1.61) for CP group; 16.87 (1.55) for TP group; 17.46 (1.65) for AP group. The SBS of the AP group was the highest while that of the C group was the lowest. SBS of specimen treated with NTAPP was significantly increased regardless of metal alloy types (p < 0.001). Within the limitations of this study, NTAPP can increases the SBS of Co-Cr alloy, CP-Ti alloy, and Ti-6Al-4V alloy with a denture base resin.

Effect of plasma surface treatment of aluminum alloy sheet on the properties of Al/Gf/PP laminates

This work deals with the plasma surface modification of aluminum alloy AA6061-T6 by changing two key parameters of processing time and working gas to enhance the interfacial adhesion between glass fiber reinforced polypropylene layer and the aluminum alloy sheet. The surface composition and morphology of aluminum alloy sheet were characterized respectively by means of XPS and SEM with EDS, while the roughness and wettability of the surface were measured by using a surftest and a contact-angle goniometry. Moreover, the interlaminar properties and static performance of Al/Gf/PP laminates were evaluated individually. The results indicated that the laminates presented higher mechanical properties, in which the aluminum alloy sheet was modified by nitrogen plasma treatment for 10 min. This is due to the synergistic mechanism of the mechanical bonding by a rough surface and the chemical bonding by functional group (CN and CN) between the aluminum alloy sheet and glass fiber reinforced polypropylene layer. In addition, compared with the phosphoric anodic oxidation, the nitrogen plasma treatment of the aluminum alloy sheet could make the interlaminar shear properties and static performance of Al/Gf/PP laminates better.

Effect of Plasma Surface Treatment on the Impact Behavior of Basalt/Epoxy Composites

In this study, the effects of surface treatment of a low-temperature atmospheric oxygen plasma on basalt/epoxy composites were investigated to improve the hydrophobility of the composite surface. After the plasma treatment, the unmodified and surface treated composite laminates have been experimentally characterized by performing contact angle measurements, low-velocity impact tests and indentation depth on the impacted laminates. Results have showed a dependence of such composite properties on the plasma coating deposition and on the treatment parameters outlining the need to optimize both the plasma power and exposition time to plasma in order to assess the efficiency of the plasma treatment and establish the optimal processing conditions.

Surface activation of High Impact Polystyrene substrate using dynamic atmospheric pressure plasma

Over the last decade, the number of researches has increased in the field of bonding technologies. Researchers attempt to improve surface adhesion properties by surface treatments. Adhesive bonding is one of these bonding techniques, where it is important to see what surfaces will be bonded. One such surface property is wetting, which can be improved by several types of surface treatment. In recent years, atmospheric pressure plasmas have appeared, with which research is ongoing on surface treatments. In our research, we will deal with the effects of plasma surface treatment at atmospheric pressure and its measurement. In addition, we summarize the theoretical background of adhesion, surface tension and surface treatment with atmospheric pressure plasma. Our goal is to improve adhesion properties and thus the adhesion quality.

The effects of plasma surface treatment on the mechanical properties of polycarbonate/carbon nanotube/carbon fiber composites

The effects of plasma surface treatment on the mechanical properties of multiscale hybrid composites consisting of polycarbonate (PC), carbon nanotube (CNT) and carbon fiber (CF) were investigated. Dynamic mechanical properties and impact energy absorption of multiscale hybrid composites fabricated under various processing conditions were measured and correlated with surface roughness and surface functionality. The highest room-temperature storage modulus (E’) of 39 GPa and absorbed impact energy of 5.3 J were obtained from the plasma-treated PC/CNT/CF composite, which are increases by 387% and 194%, respectively, as compared to the neat PC/CF composite. Although the plasma treatment was more efficient for the PC/CF composites rather than the PC/CNT/CF composites, hybridization of CNT showed synergistic effects on the enhancement of mechanical properties due to the combination of increased surface roughness and functionality as well as the bridged modulus gap between PC and CF.

Effect of plasma surface treatment of poly(dimethylsiloxane) on the permeation of pharmaceutical compounds

This paper addresses the modification of poly(dimethylsiloxane), i.e. PDMS, using plasma surface treatment and a novel application of the membrane created. A set of model compounds were analysed to determine their permeation through PDMS, both with and without plasma treatment. It was found that plasma treatment reduced permeation for the majority of compounds but had little effect on some compounds, such as caffeine, with results indicating that polarity plays an important role in permeation, as is seen in human skin. Most importantly, a direct correlation was observed between plasma-modified permeation data and literature data through calculation of membrane permeability (Kp) values suggesting plasma-modified silicone membrane (PMSM) could be considered as a suitable in vivo replacement to predict clinical skin permeation.

EFFECT OF PLASMA SURFACE TREATMENT OF POLYMERIC SUBSTRATES ON THE ADHESION OF JET-PRINTED SILVER NANOPARTICLE LAYERS

The effect of plasma surface treatment of polymer films on adhesion of jet printed silver nanoparticles layers was studied. The measurements were carried out by using of tensile testing machine. After plasma treatment an increase by 75% in adhesion was measured on the polyethylene terephthalate substrate, while the values on polyimide remain at the same level.Ref. 23, fig. 7.

Effects of plasma surface treatment on bending strength and modulus of elasticity of beech and poplar plywood

This is a study on the effect of plasma treatment with different gases and plasma intensity on the bending strength and modulus of elasticity of plywood manufactured from beech and poplar. Oxygen (O2) and ammonia (NH3) plasma were applied on the veneer sheets; two plasma intensities were applied on the veneers with 150 and 300 W in the plasma chamber during one minute. Phenol formaldehyde resin was applied on one surfaces of each veneer with approx. 160 g/m2. Bending strength and modulus of elasticity were determined according to EN 310.The effects of plasma surface treatment on chemical structure of the panels were determined with FTIR-ATR analysis. Bending strength of all tested panels slightly and partly increased without statistical significance when applying oxygen plasma. The effect of ammonia plasma treatment on bending strength and was determined by the wood species and the plasma intensity, and it was not uniform. Modulus of elasticity of the panels with oxygen plasma treatment showed in most cases improvement, whereas ammonia plasma pretreated veneers caused lower values compared to the control panels.

Effect of plasma surface treatment on embedded n-contact for GaN-based blue light-emitting diodes grown on Si substrate

Unlike the finger-like n-contact that is prepared after the wafer bonding and the N-polar GaN surface roughening for GaN-based vertical structure light-emitting diodes (LEDs) grown on Si substrates, the embedded via-like n-contact is formed prior to the wafer bonding. The high temperature process of the wafer bonding often causes the electrical characteristics of the via-like embedded n-contact to degrade. In this paper, we study in detail the effect of plasma treatment of the n-GaN surface on the forward voltage of GaN-based LED grown on Si substrate. It is shown that with no plasma treatment on the n-GaN surface, the forward voltage (at 350 mA) of the 1.1 mm1.1 mm chip with a highly reflective electrode of Cr (1.1 nm)/Al is 3.43 V, which is 0.28 V higher than that of the chip with a pure Cr-based electrode. The LED forward voltages for both kinds of n-contacts can be reduced by an O2 plasma treatment on the n-GaN surface. But the LED forward voltage with a Cr/Al-based electrode is still 0.14 V higher than that of the chips with a pure Cr-based electrode. However, after an Ar plasma treatment on the n-GaN surface, the LED forward voltage with a Cr/Al-based electrode is reduced to 2.92 V, which is equal to that of the chip with a pure Cr-based electrode. The process window of the n-GaN surface after the Ar plasma treatment is broader. X-ray photoelectron spectroscopy is used to help elucidate the mechanism. It is found that Ar plasma treatment can increase the concentration of N-vacancies (VN) at the n-GaN surface. VN acts as donors, and higher VN helps improve the thermal stability of n-contact because it alleviates the degradation of the n-contact characteristics caused by the high temperature wafer bonding process. It is also found that the O content increases slightly after the Ar plasma treatment and HCl cleaning. The O atoms are mainly present in the dielectric GaOx film before the Ar plasma treatment and the HCl cleaning, and they exist almost equivalently in the conductive GaOxN1-x film and the dielectric GaOx film after Ar treatment and HCl cleaning. The conductive GaOxN1-x film and the VN donors formed during the plasma treatment can reduce the contact resistance and the LED forward voltage.

The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro).

Background:The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues.Objective:This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti–6Al–4V).Materials and Methods:Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR).Results:Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material.Conclusions:Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface.

The effect of plasma surface treatment on push-out bond strength of fiber-reinforced posts to root canal dentin

Objectives : This study evaluated the effect of surface treatment with plasma or sandblasting on push-out bond strength of fiber post bonded to root canal dentin. Methods : Crowns of 50 teeth were sectioned and their root canals were instrumented, obturated and received post-space preparations. The roots were equally divided into five groups according to post surface treatment. Posts were surface treated with oxygen plasma in Group 1 and argon plasma in Group 2. Post surfaces were treated with sandblasting in Group 3 and silanized after sandblasting in Group 4. In control group (Group 5), posts were cemented to the canal wall without surface treatment. After post cementation, push-out test was used to evaluate the bond strength of fiber post bonded to root canal dentin. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney tests (α = 0.05). Results : Oxygen plasma revealed the significantly highest push-out bond strength of all groups ( P Conclusions : Oxygen plasma treatment of fiber post recorded the highest bond strength to root canal dentin followed by sandblasting. Silanization and Argon plasma did not play a significant role in enhancing bond strength of fiber posts to canal dentin. Clinical significance: Oxygen plasma surface treatment offered the highest resistance to displacement of fiber posts. Clinical trials involving plasma technique are indicated.

Influence of Plasma Treatment on the Surface Properties and Strength of Bonded Joints at Selected Polyolefins

Bonding has experienced an enormous expansion in the various applications during the last few years in the field of material joining, due to which it is classified as a new joining technology, although it is, in fact, very old. Compared with the conventional joining methods (riveting, screwing and welding), bonding provides a new material combination possibilities and it allows us to obtain special shapes and properties, which can not be formed by conventional methods. To create a high-quality bonded joint, it is important to wet the bonded surface very well wetted by a wetting liquid. The wettability of the material is characterized by a contact angle of wetting, by which the surface energy is subsequently determined. For a high quality of the joint, the bonded material must have higher surface energy than the witting liquid (adhesive) [1-3]. This paper describes the effect of plasma surface treatment on the surface properties (surface energy, microhardness) of low-density polyethylene (LDPE) and high-density polyethylene (HDPE), and also on the final strength of bonded joints. The measured results indicate, that plasma surface treatment is very effective tool for improvement of surface properties and strength of bonded joints of HDPE and LDPE. The strength of bonded joints after plasma surface treatment was increased up to 350 % compared to untreated material. A similar trend was observed even for surface energy and microhardness of materials.