Improvement Of Wettability Research Articles

Irradiation influence on Mylar and Makrofol induced by argon ions in a plasma immersion ion implantation system

Mylar and Makrofol polycarbonate polymers were irradiated by Ar ions in a plasma immersion ion implantation (PIII) system. The surface wettability of both polymers was investigated by employing the contact angle method. The measured contact angles were found to depend on the surface layer properties. Good wetting surfaces were found to depend not only on surface roughness but also on its chemistry that analyzed by Fourier transform infrared (FTIR) spectroscopy. Surfaces topography and roughness was investigated and correlated to their surface energy which studied with the aid of acid-base model for evaluating the improvement of surface wettability after irradiation. PIII improves polymers surface properties efficiently in a controllable way.

Saccharose as a New Space Holder Material for Porous Titanium Implant Formation

This paper investigates the properties of Ti scaffolds with a porosity of 73%. In the processing route, a new space holder material was applied - saccharose, commonly known as table sugar. Porous Ti was made by the dissolution of sugar crystals from the Ti-sugar green compact and final sintering of the remaining Ti scaffold. The sintered scaffolds showed uniform pore distribution. The pores had polyhedral shape and their dimensions reached 1 mm. The scaffolds were made and investigated with respect to possible medical applications. After all processing stages, the surface was oxidized and showed average wettability with the lowest wetting angle of 81.5o, which was strongly correlated with the condition of the surface. The chemical etching in an HF solution resulted in a strong wettability improvement. Due to very high porosity, the compression strength (1.48 MPa) and Young’s modulus (33.7 MPa) of the scaffolds were relatively low.

Wettability of transparent YAG (Y3Al5O12) by molten Ag–Cu–Ti alloys

The wetting of transparent YAG (Y3Al5O12) by alloys of the AgCuTi system has been studied for the first time. The role of the activity of Ti in determining the interactions between the brazing alloys and the YAG substrate has been analyzed by CALPHAD method. The low contact angle values ensure very good (at 950°C) and fair (at 850°C and 820°C) wettability conditions. A significant reactivity occurred at the solid–liquid interfaces, with the formation of new phases. TiY2O5 was found at Ag–Ti/YAG interfaces, while a second layer, identified as “M4X”, associated to the significant wettability improvement, was specifically found only in the AgCuTi/YAG samples tested at 950°C. All these phases were identified by the newly calculated Ag–Cu–Ti phase diagram and were confirmed by SEM and EDS analyses. The obtained good wettability and the maintained transparency of the YAG are promising for the production of brazed optical windows to be used under extreme conditions.

Effects of fullerenes reinforcement on the performance of 96.5Sn–3Ag–0.5Cu lead-free solder

In this study, fullerenes (FNSs) nanoparticles with different weight fractions (0.05, 0.1 and 0.2wt%) were successfully integrated into SAC305 lead-free solder utilizing a powder metallurgy route. The composite solders were then studied extensively concerning their microstructures, wettability, thermal and mechanical properties. Refined microstructures were observed in the matrices of the composite solders after the addition of FNSs nanoparticles to the solder alloy. With an increase in the amount of FNSs nanoparticles added, the composite solders exhibited a homologous improvement in wettability. Furthermore, the electrical resistance and melting point of the solder changed only marginally after the addition of the FNSs nanoparticles. According to the mechanical results, the 0.2wt% FNSs addition would give rise to a 12.1% and 19.9% improvement in shear strength and microhardness respectively in comparison to the unreinforced solders. These progressions can be attributed to the refined microstructures and the presence of uniformly dispersed FNSs nanoparticles, which acted as reinforcements. Finally, the existence of added FNSs nanoparticles in the solder matrix was further confirmed by energy-dispersive X-ray spectroscopy, scanning electron microscopy, and Raman spectroscopy.

Carbonate and sandstone reservoirs wettability improvement without using surfactants for Chemical Enhanced Oil Recovery (C-EOR)

In this paper, we have been proposed the preparation of Silica–MWCNT nanohybrid that can increase the water wettability of carbonate and sandstone reservoirs. Chemical agents such as surfactants have been used as wettability modifiers to increase oil recovery from oil-wet carbonate and sandstone reservoirs. Addition of chemical compounds such as polymers, ionic materials and nanoparticles can improve the effectiveness of the mentioned chemical agents.The effectiveness of nanohybrids without using surfactants has not been reported yet and it is still in its infancy. In this work, the effect of MWCNT–SiO2 nanohybrid-based nanofluids on the wettability alteration of a carbonate and a sandstone reservoir rocks was experimentally studied. Therefore, MWCNT–Silica nanohybrid has been prepared by adding the suitable amount of MWCNT in situ of silica nanostructure preparation. In this research, MWCNT–Silica nanohybrid was prepared with ultrasound assisted sol–gel method and characterized with X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM) and Transmission Electron Microscopy (TEM). The effect of the related nanofluid on the wettability of carbonate and sandstone rocks was investigated by measuring contact angle and interfacial tension. Results show that the nanofluid could significantly change the water wettability of the mentioned rocks from oil-wet to water-wet condition without using surfactant.

Effect of surface modification on starch biopolymer wettability

The main goal of this paper was to determine wettability properties of native starch and starch modified by antibacterial solution of chitosan or lysozyme as a function of temperature and/or after plasma treatment. Contact angles for polar water (and formamide) and nonpolar diiodomethane on glass plates covered with starch film before and after gelatinization (25 °C, 37 °C and 60 °C) were measured. The surface free energy of solid (gel) was determined from the advancing and receding contact angles of these probe liquids, using the contact angle hysteresis model (CAH). The plasma treatment was immediately followed by a sharp decrease of contact angle. In the course of ageing the contact angle also decreased due to the reorientation of polar groups into the surface layer of polymer. Also a sharp decrease in negative values of WS takes place which indicates more hydrophilic character of starch after plasma treatment. The same was after lysozyme modification but to a smaller extent. The opposite trend of changes was visible after chitosan solution treatment. The surface characterization was observed by FTIR measurements and surface topography from the profilometer images and such measurements well support the contact angle results. The arrangement of temperature, plasma treatment or biological modification can lead to improvement of starch surface wettability and stability. The obtained results open up possibilities of starch application in food, paper and packaging industries as well as in pharmacy.

Effect of surface modification on starch/phospholipid wettability

Abstract The objective of this work was to determine surface properties of biopolymer film as a function of temperature and/or after plasma treatment with the aim of further wettability tests and biocompatibility. The examined biopolymers were native starch and starch modified by solution of PC (phosphatidylcholine). Contact angles for polar water (and formamide) and nonpolar diiodomethane on the glass plates covered with starch film before and after gelatinization (25 °C, 37 °C and 60 °C) were measured for the base and plasma modified film. The surface free energy of solid (gel) was determined from the advancing and receding contact angles of these probe liquids, using the contact angle hysteresis model (CAH). The plasma treatment was immediately followed by a sharp decrease of contact angle and in the course of ageing the contact angle also decreased due to the reorientation of polar groups into the polymer surface layer. To depict better changes in hydrophilic/hydrophobic character of the starch surface before and after modification the work of water spreading, W S was calculated. A sharp decrease in negative values of W S takes place which indicates more hydrophilic character of starch surface after modification. Surface morphology and roughness were studied by optical profilometer and FTIR measurements which confirm the contact angle results. It was also proved that a combination of input treatment parameters led to improvement of biopolymer wettability and provided possibilities of starch application where uniform thin films are required.

Physicochemical Characterization and In-Vitro Dissolution Enhancement of Bicalutamide-Hp-Β-Cd Complex

Abstract: Inclusion complex has been used as effective metllhod to improve the dissolution properties and bioavailability of poorly water soluble drugs. The aim of present study was to improve the dissolution rate of poorly soluble drug, bicalutamide (BIC), by cyclodextrin inclusion complexation. The phase solubility profile of bicalutamide with hydroxypropyl-β-Cyclodextrin (HP- β-CD) was classified as An-type. Stability constant with 1:2 molar ratio was calculated from the phase solubility diagram. Gibbs free energy (ΔGtr) values were negative, indicating the spontaneous nature of BIC solubilization. Solid inclusion complexes were prepared at 1:1.5, 1:2 drug/carrier ratio by physical mixing, kneading method and solvent evaporation techniques. Optimized complex was characterized by using FTIR and differential scanning calorimetry. It could conclude that stability of BIC and the absence of well define drugpolymer interaction. Inclusion complex prepared by kneading method showed the most improvement in wettability and dissolution rate as compare with pure BIC and physical mixture. Tablets prepared using optimized ratio with HP-β-CD showed significant improvement in the release profile of BIC as compared with marketed tablets (CALUT).

Incorporation of polymerizable surfactants in hydroxyethyl methacrylate lenses for improving wettability and lubricity

Dryness and discomfort are the main reasons for dropouts in contact lens wearers. Incorporating surfactants in lens formulations could improve wettability and lubricity, which can improve comfort. We have focused on incorporating polymerizable surfactants in hydroxyethyl methacrylate lenses to improve comfort, while minimizing the potential for surfactant release into the tears. The surfactants were added to the polymerization mixture, followed by UV curing and extraction of leachables in hot water. Wettability and lubricity were characterized by measuring the contact angle and coefficient of friction. Lenses were also characterized by measuring transmittance, loss and storage moduli and ion permeability. Incorporation of surfactants significantly reduced contact angle from 90° for p-HEMA gels to about 10° for 2.43% (w/w) surfactant loading in hydrated gel. The coefficient of friction also decreased from about 0.16 for HEMA gels to 0.05 for the gels with 2.43% surfactant loading. There was a good correlation between the contact angle and coefficient of friction suggesting that both effects can be related to the stretching of the surfactant tails near the surface into the aqueous phase. The water content was also correlated with the surfactant loading but the contact angle was more sensitive suggesting that the observed improvements in wettability and lubricity arise from the protrusion of the surfactant tails in into the liquid, and not purely from the increase in the water content. The gels were clear and certain compositions also have the capability to block UVC and UVB radiation. The results suggest that incorporation of polymerizable surfactants could be useful in improving surface properties without significantly impacting any bulk property.

Effect of nano-Fe2O3 additions on wettability and interfacial intermetallic growth of low-Ag content Sn–Ag–Cu solders on Cu substrates

In the present study, Fe2O3 nanoparticles were synthesized and smelted with pure Sn, Ag, and Cu to prepare Sn–1.0Ag–0.7Cu–xFe2O3 nano-composite solders. The content of Fe2O3 nanoparticles ranged from 0 to 1wt.% in the solders. The influences of Fe2O3 nanoparticles on the wettability and the morphology of interfacial intermetallics compounds (IMCs) of low-Ag Sn–Ag–Cu solders on Cu substrate were investigated. Results show that added Fe2O3 nanoparticles can remarkably improve the wettability of Sn–1.0Ag–0.7Cu solder alloys and inhibit the formation and the growth of the interfacial IMCs between the nano-composite solders and Cu substrate. Meanwhile, not only the wettability of the nano-composite solders but also the formation and the growth of the interfacial IMCs, during reflow and aging, are identically relied on Fe2O3 weight percent in nano-composite solders. The enhancement of wettability improvement and interfacial IMC inhibition caused by nano-Fe2O3 addition increased with the addition amount under small concentration. However, excessive addition of Fe2O3 nanoparticles in the Sn–1.0Ag–0.7Cu solder alloys will degrade the wettability and the inhibition effect on the interfacial IMCs. There is an optimum amount of Fe2O3 nanoparticles in Sn–1.0Ag–0.7Cu solder alloys, which is 0.4wt.%, and Sn–1.0Ag–0.7Cu–0.4Fe2O3 solders possess the best wettability and the inhibition effect on the interfacial IMCs formation and growth. The reason for improving wettability and simultaneously inhibiting IMCs formation and growth due to Fe2O3 nanoparticles addition is explained.

Modification of properties of yttria stabilized zirconia epitaxial thin films by excimer laser annealing.

This study focuses on the ultrafast improvement of surface wettability, electrical, and room temperature magnetic characteristics of cubic zirconia single crystalline thin films after laser annealing. The point defects generated by the laser treatment are envisaged to play a critical role in altering the above properties. Yttria stabilized zirconia (YSZ) thin films were epitaxially grown on Si(100) substrates by pulsed laser deposition technique and subsequently annealed by a KrF excimer laser beam (τ = 25 ns) using low-energy laser pulses. An atomically sharp interface, parallel to the film free surface, between laser annealed layer and the pristine region was observed. The single crystalline nature of thin films was preserved following the laser treatment. The laser-solid interaction with YSZ led to the introduction of point defects, i.e., oxygen vacancies, resulting in a strained structure which, in turn, resulted in the formation of a tetragonal-like zirconia. With the increase of number of laser pulses the laser treated films got highly disordered due to the high concentration of the point defects, while maintaining their crystalline nature. Although the surface of the pristine sample showed weak hydrophilic characteristics (contact angle ∼ 73°), the laser annealed samples exhibited significantly improved hydrophilic characteristics. It was found that there is an optimum number of laser pulses where the maximum hydrophilicity (contact angle ∼ 22°) is obtained. The carrier concentration in the sample with the highest hydrophilicity was determined to be higher by about 5 orders of magnitude compared to the pristine sample. This sample possessed the lowest electrical resistivity. The laser annealed YSZ epilayers showed a superior room-temperature ferromagnetic behavior, compared to the pristine samples. A 2-fold enhancement in the magnetization of the samples was observed following the laser treatment which is a clear demonstration of the key role of defects and their transient distribution throughout the lattice. All these observations were correlated with the formation of point defects due to the photon interaction with YSZ and absorption of energy of the KrF laser photons to produce defects.

Surface modification of polypropylene separators in lithium-ion batteries using inductively coupled plasma treatment.

We describe herein an improvement in the surface wettability of plasma-treated separators for use in lithium-ion batteries. We treated the separators with an O2/Ar inductively coupled plasma to increase their surface energy. The plasma treatment on the separator and plasma diagnostic experiments were performed in an inductively coupled plasma (ICP) reactor. The fraction of Ar in the O2/Ar plasma was changed from 0% to 100%. The plasma diagnostics were performed using optical emission spectroscopy and a double Langmuir probe. To confirm the morphological change of the separator membrane by the plasma treatment, we used the scanning electron microscopy. The surface energy measurements were performed using the drop method. We found that the plasma treatment transformed the separator from a hydrophobic membrane to a hydrophilic one, thereby achieving high separator wettability. After the treatment of the separators with O2/Ar plasma, the batteries exhibited better cycle performance and rate capacity than those employing the untreated ones.

Structure Property Correlation of Al Based MMC Reinforced with Cu Coated Rice Husk Ash SiO2 Particles

Metal coated reinforcements in metal matrix composites are advancing in the field of engineering to produce high quality composites by liquid metallurgy route due to improvement of wettability between reinforcement and matrix. In the present study, a comparative analysis of mechanical properties was carried out on Al based composite (with varying wt% of Mg) reinforced with uncoated and Cu coated RHA (rice husk ash) SiO2 particles. Tensile testing results of the composites indicate that UTS and YS of the composites reinforced with Cu coated SiO2 particles was significantly higher than uncoated particles. The Cu coated SiO2 particles act as a protrusion over the matrix carrying the major portion of the applied tensile load and thus composites are protected from failure. When Mg reaches 1.5 wt%, wettability of matrix with reinforcement is maximum, leading to the formation of hard compounds such as CuO, CuAlO2 and Al2CuMg at interface. This enhances interfacial bonding strength as well as load transfer from matrix to reinforcement, which leads to higher tensile strength along with ductility.

Wettability Improvement of Poly (Butylene Terephthalate) Nanofibrous Mats Prepared via Electrospinning by Blending With Regenerated Silk Fibroin

Poly (butylene terephthalate) (PBT)/regenerated silk fibroin (RSF) blend electrospun nanofibrous mats were manufactured to combine the excellent mechanical behavior of PBT with the extraordinary hydrophilic property of RSF. A 1:1 mixture of trifluoroacetic acid (TFA) and dichloromethane (DCM) was adopted as the solvents for PBT and RSF with 20% (w/v) PBT and 16 wt% RSF solutions being mixed in various proportions for electrospinning. The morphology, crystallization, Fourier transform infrared (FTIR) spectra, surface roughness, contact angle, and wetting time of the electrospun blended materials were studied. When the weight ratio of RSF was larger than 50%, a water drop on the surface of the electrospun mat was completely permeated within 300 s or less. Besides the chemical influence of the amino and carboxy groups in RSF, the physical characteristics of the RSF in the blend electrospun mats, such as random coil structure, lower crystallinity, rougher surface than PBT, etc., were a partial reason for the improvement of wettability. The blend nanofibrous mats may be especially applicable in biomedical fields.

Effect of Wood Surface Modification by Atmospheric-Pressure Plasma on Waterborne Coating Adhesion

In this study, the effect of an atmospheric-pressure plasma treatment on the surface properties of sugar maple (Acer saccharum March.) and black spruce (Picea mariana (Mill.) was analyzed by contact angle measurement and a water-based coating pull-off testing. The plasma gases used were Ar, N2, CO2, and air. It was found that the wettability with water and the coating adhesion of maple and spruce can be highly influenced by the nature of the plasma gas used and the plasma treatment time. For example, in the case of sugar maple, coating adhesion increased by 66% after 1.5 s of exposure to argon plasma. Repetition of the contact angle measurement one and two weeks after the initial plasma treatment showed that the plasma-induced modification is not permanent. Improvements in wettability and adhesion were also obtained with simpler, cheaper air plasmas, a result promising for the development of advanced plasma reactors operating at atmospheric pressure, specially designed for the wood industry.

The improvement of wettability, biotribological behavior and corrosion resistance of titanium alloy pretreated by thermal oxidation

The thermal oxidation process was performed on biomedical titanium alloys to improve surface properties for the application in artificial cervical disc. The pretreated Ti6Al4V was characterized with XPS, XRD and SEM. The wettability, biotribological behavior and corrosion resistance were evaluated under distilled water and 25wt% bovine serum lubricant. Rutile TiO2 as the main compound was formed with the increase in hardness. The wettability was improved significantly after oxidation. Compared with the untreated, the friction coefficients and wear volumes of treated samples all decreased with about 50% reduction in both dry sliding and lubrication conditions. Corrosion resistance for oxidized samples was also enhanced with a big reduction of corrosion current density and a shift in corrosion potential towards the positive direction.

Effects of Co-spray Drying of Surfactants with High Solids Milk on Milk Powder Wettability

Dairy industries often spray lecithin, a food-grade surfactant, to spray-dried whole milk powders while fluidisation to produce instant powders. Though adding surfactant to milk feed was often reported to improve the wettability of dried powders, this approach was not favourably used. The present study investigated the effects of surfactant addition into high solids milk feed before drying on the wettability of whole milk particles. Adding either 0.1 wt.% Tween 80 or 0.1 wt.% lecithin to un-concentrated whole milk led to a significant wettability improvement of spray-dried powders. At higher feed solids levels of 23 and 33 wt.%, the wetting process of pure milk powders was comparatively rapid, but the surfactant-added powders showed similar wettability to the pure milk powders. The development of powder wettability as drying progressed was investigated using single droplet-drying technique for 32 and 43 wt.% whole milk in the presence and absence with surfactants. The technique captured an advanced shell formation during drying of higher solids milk. The wettability of surface shells formed by surfactant-added milk was similar to those formed by pure milk throughout drying, from initial shell formation to final drying stage. By contrast, coating surfactants on the outer layer of particles being dried could substantially improve wettability. The rapid shell formation and the slow material diffusion owing to the high medium viscosity were considered the main factors limiting the migration of surfactant molecules towards droplet surface during drying.

Enhancing Ni anode performance via Gd2O3 addition in molten carbonate-type direct carbon fuel cell

Recently, there is a consensus that a limited performance in direct carbon fuel cell (DCFC) using molten carbonate electrolyte is caused by the limited triple phase boundaries (TPB) formation. In order to solve this problem, we added Gd2O3, a well-known lanthanide oxide material for the improvement of wettability in the Ni anode. As a result, it was clearly shown that the voltage drop level and charge transfer resistance was decreased, and therefore the peak power density was increased by almost two times that of solely Ni anode to reach up to 106.7 mW/cm2 with carbon black and 114.1 mW/cm2 with actual coal fuel. The increased wettability led to the improvement of triple phase boundary (TPB) formation and consequently the enhancement of DCFC performance. While the wettability was increased with oxide content in Ni anode, the proportion of Ni at the surface of anode and the electronic conductivity was gradually decreased. With this reason, the peak power density showed the volcano type change with the amount of Gd2O3 addition. Finally, it was revealed that the optimum composition for the anode was Ni:Gd2O3 = 1:5 in weight ratio.

Electron beam induced surface modifications of PET film

The semi-crystalline poly (ethylene terephthalate) PET film was treated by low energy electrons with different fluences and the surface wettability modification is investigated. Contact angle technique is employed to prove PET surface wettability enhancement. The contact angle decreases due to alteration of surface chemistry, morphology and free energy after electrons irradiation. Fourier transform infrared spectroscopy (FT-IR) shows the creation of polar groups on the surface which are responsible for surface wettability improvement. Atomic force microscope (AFM) observations reveal that the surface roughness changes after electrons–PET interactions. Surface free energy analysis has been observed as well. Low energy electrons irradiation of PET film improves and controls its wettability, adhesion and then biocompatibility.

Cu filling of 10 nm trenches by high-magnetic-field magnetron sputtering

Ru and Cu sputterings were performed with two different high-vacuum sputtering systems. The Ru sputtering was performed by high-vacuum sputtering. On the other hand, the Cu sputtering was performed by high-magnetic-field sputtering. High-magnetic-field sputtering, which entails a Cu deposition rate of 80 nm/min (target–substrate distance: 200 mm) at a sputtering pressure of 7 × 10−2 Pa, is used for the Cu filling of 10-nm-wide Ru-lined trenches with an aspect ratio of 6.5. The complete Cu filling of trenches is accomplished within 1 min of sputtering time using a 1 at. % N2–Ar sputtering gas. The reason for the complete Cu filling is considered in terms of the capillary theory, focusing on the wettability of Cu on Ru. The improvement in Cu wettability with the use of a N2 additive is also evaluated in terms of the contact angle for Cu on Ru and surface shape.