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Currently, with the gradual development of anticorrosive coatings, the pursuit of simple preparation methods and the improvement of anticorrosive coatings' properties have become the major research trends. This study successfully prepared a hydrophilic super anticorrosive coating through a simple mixing method. The coating has a contact Angle of 67.8° and a rolling Angle greater than 20°. This coating can withstand 180 days of salt spray test with no bubble or rust formation when placed on a Q 235 substrate in a 3.5 wt % NaCl solution, demonstrating the excellent corrosion resistance of the AO0.4AN0.6EP coating. Furthermore, after being immersed in a 3.5 wt % NaCl solution for 3 days, the AO0.4AN0.6EP coating exhibited the largest impedance diameter (2.07×108 Ω⋅cm2), almost three times larger than other coatings, and possessed the highest Bode modulus value, one order of magnitude higher than other coatings. After immersion in a 3.5 wt % NaCl solution for 7 days, the AO0.4AN0.6EP coating had the largest Ecorr and the smallest icorr, indicating its superior corrosion resistance. In addition to corrosion resistance, the AO0.4AN0.6EP coating showed no signs of cracking, discoloration, or decomposition after being exposed to ultraviolet aging lights for 30 days, demonstrating its excellent UV resistance. Moreover, neither dry soil particles nor muddy water could adhere to the coating surface, proving its good self‐cleaning ability. Therefore, this coating holds promising applications in the field of super corrosion‐resistant coatings. [ABSTRACT FROM AUTHOR]

In recent years, there has been growing interest in using polymer nanocomposite membranes as a more advanced method for removing pollutants from water and treating wastewater for various purposes. In this study, thin‐film nanocomposite (TFN) membranes of polycarbonate/polyvinyl alcohol–titanium dioxide thin‐film (PC/PVA–TiO2) were fabricated by dip‐coating a PC substrate in a PVA/TiO2 solution. Various methods, including attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, field emission scanning electron microscopy (FE‐SEM), atomic force microscopy (AFM), and water contact angle were utilized to assess the structural characteristics of the produced membranes. The PC/PVA thin‐film composite (TFC) and PC/PVA–TiO2 TFN membranes were then examined in a submerged membrane system to evaluate their effectiveness in filtering humic acid (HA) under various vacuum transmembrane pressure (0.3 and 0.6 bar) condition. The FTIR‐ATR results confirmed the formation of the active layer of PVA/TiO2 nanoparticles (NPs). It was observed that adding 1 wt.% of TiO2 NPs to the active layer of PVA/TiO2 significantly enhanced the water contact angle from 77.5° for PC support to 55.3° for PC/PVA–TiO2 (0.1) TFN membranes. Furthermore, the FE‐SEM results confirmed the formation of an active layer of PVA/TiO2 with a thickness of 237.87 nm. The pure water flux increased from 101.64 L/m2h for the PC/PVA TFC membrane to 144.02 L/m2h and 199.09 L/m2h for the PC/PVA–TiO2 (0.05) and PC/PVA–TiO2 (0.1) TFN membranes, respectively. Also, the results revealed that at lower transmembrane pressure, all membranes showed higher value in HA removal as compared to when higher transmembrane pressure was used. [ABSTRACT FROM AUTHOR]

The effect of biphilic surfaces on subcooled flow boiling in a horizontal rectangular duct was investigated. Biphilic surfaces were created on an aluminum alloy substrate in the form of juxtaposed Hydrophobic (HPo) and Hydrophilic (HPi) transverse strips. In this regard, two different testing samples with strip widths of 10 and 18 mm were prepared, named pattern I and pattern II, respectively. Using Deionized Water (DIW), the experiments were performed with the two mentioned biphilic patterns and a plain surface. Finally, different cases were compared, and the results were interpreted. The results showed that the biphilic surfaces improve the Heat Transfer Coefficient (HTC) and cause boiling to be initiated at a lower wall temperature. In this regard, pattern I and pattern II represent 22 and 40% improvement in HTC, and boiling initiates 31 and 33.5 °C sooner compared to the plain surface, respectively. In addition, the experiments were also conducted with an Ethylene Glycol/Water mixture (EG/W) in the same manner. The results revealed that EG/W represents smaller HTC values for all cases and shifts the boiling points to higher wall temperatures compared to DIW. It is worth mentioning that the major amount of this HTC reduction is occurred in the single-phase area, in lower wall temperatures. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is an inert polymer that is very difficult to dye and finish. In the current work, PP fabrics were activated by an oxygen plasma beam, followed by treatment with a renewable natural biopolymer, namely keratin, in the presence of glutardialdehyde as a crosslinker using the pad-dry-cure method. The treated PP fabric exhibited adequate hydrophilic characteristics which make it dyeable with cationic dyestuffs with excellent fastness properties. The effects of curing time and temperature on the fibers' weight, strength, elongation, wettability, and yellowness were monitored. Fourier transform infrared (FTIR) and nuclear magnetic resonance (1H NMR) spectroscopy were used to verify the formation of polar functional groups within the chemical structure of the treated PP fabrics. The proposed method has a positive effect on some of the comfort attributes of the treated PP fabrics, such as the enhanced resistance to ultraviolet rays as well as the accumulation of electrostatic charge without deterioration in the fabrics' inherent properties. The microscopic investigation using scanning electron microscopy demonstrated a coating of PP fabric with a layer of keratin. The induced effect was durable in terms of their wettability and dyeability, against washing for up to 20 washing cycles, indicating the formation of a fortified bond between the O2-plasma-irradiated PP fabric and keratin. [ABSTRACT FROM AUTHOR]

Rubber particles have good energy absorption and deformation ability. The incorporation of rubber particles into cement base can effectively improve the toughness of the material, and enhance the freezing resistance, cracking resistance, impact resistance and other properties of cement base. However, because rubber particles are a kind of hydrophobic substance, the interface bonding force between rubber and cement slurry is weak, and the strength of cement-based materials is decreased. Therefore, chemical and physical modification of rubber cement-based materials is studied. The results show that the modified rubber can enhance the properties of cement-based materials in two ways. First, the modifier can improve the hydrophilic of rubber by dissolving the impurities on the surface of rubber particles and forming a film on the surface. Second, the modifier reacts with the hydration product to form an effective chemical cross-link, so that the rubber particles form a close connection with the cement slurry. At the same time, it is found that rubber particles and fiber polymers have synergistic effect on the strengthening and toughening of cement-based materials. [ABSTRACT FROM AUTHOR]

In this study, the heat transfer performance of a two-phase closed thermosyphon with super-hydrophobic (SH-phobic) condenser and super-hydrophilic (SH-philic) evaporator is investigated, and the results are compared with those of a bare condenser. At 100–200 W, the total thermal resistance on the SH-phobic surface decreases by up to 10.40 %, 0.41 % and 27.44 % compared with the bare condenser surface at filling ratios of 0.25, 0.5, and 0.75, respectively. However, the total thermal resistance increases by 55.06 %, 411.35 % and 128.33 % from 300 to 400 W, respectively. The critical heat flux for the SH-phobic surface is lower than for the bare surface. The SH-phobic surface performs better than bare surface in the low-power region (100–200 W), but not in the high-power region above 300 W. Therefore, the input power should be considered when applying the SH-phobic surface to the condensing section. [ABSTRACT FROM AUTHOR]

Although multifunctional textiles are the need of the hour, achieving this multifunctionality by using renewable, sustainable resources while keeping production costs at the lowest is vital for the survival of mankind. This study reports a sustainable, superhydrophilic, antioxidant, antibacterial textile fabric which was achieved by using silk sericin as a finish and polylactic acid, a biobased fiber, as a substrate. Initially, silk sericin was treated with 2,3-epoxypropyltrimethylammonium chloride to enhance its antibacterial activity. The fabric surface was treated with alkali to impart reactivity and make finishing durable. FTIR, XPS, and Raman spectroscopy of sericin after modification revealed that sericin has covalently bonded to 2,3-epoxypropyltrimethylammonium chloride and conductive titration revealed that the degree of substitution is 0.09 per bulk sericin unit. The polylactic acid fabric after treatment with modified sericin exhibited 100% antibacterial activity and 0° water contact angle, while the fabric's mechanical strength loss was acceptable (< 10%). The treated fabric sustained its superhydrophilicity and 100% antibacterial activity even after five accelerated Launder–Ometer washing cycles. Hence, the reported strategy provides a sustainable, durable, economical, and scalable way to achieve superhydrophilic, antioxidant, and antibacterial textile fabric. [ABSTRACT FROM AUTHOR]

Carbon fiber (CF)‐reinforced epoxy resin (EP) composites are lightweight materials with excellent comprehensive performance. However, the flammability of EP and the poor interfacial bonding between CF and EP are two key disadvantages that limit their further applications. Here, a kind of water‐soluble lignin‐based CF sizing agent (ELBEDK) is prepared through hydrophilic modification of enzymatic lignin, which can significantly enhance the interfacial interaction between CF and EP. Additionally, a highly efficient intumescent flame retardant (LMA) is prepared. The EP, enzymatic lignin, LMA and CF sized ELBEDK are compounded to obtain the fire‐safety CF reinforced composites (SCF/FEP/L). The flame retardancy of SCF/FEP/L with 7% LMA (SCF/FEP7) reached V‐0 rating. Moreover, SCF/FEP/L with 7% LMA and 15% lignin (SCF/FEP7/L15) present an limiting oxygen index (LOI)of 30.2% and V‐0 of UL‐94. Specifically, the total smoke production and the heat release rate are 47.8% and 46.81% lower than that of SCF/EP, respectively, indicating the improved smoke suppression and flame retardancy. The IFSS and flexural strength of SCF/FEP7/L15 are improved to be 59.4 MPa and 511.1 MPa, respectively. This study presents a simple approach to fabricate low‐cost high performance lignin‐based flame retardant CF/EP biocomposites with wide application potential. [ABSTRACT FROM AUTHOR]

Polyamide-6 (PA) is a popular textile polymer having desirable mechanical and thermal properties, chemical stability, and biocompatibility. However, PA nanofibers are prone to bacterial growth and user discomfort. ε-Poly-L-lysine (PL) is non-toxic, antimicrobial, and hydrophilic but lacks spinnability due to its low molecular weight. Given its similar backbone structure to PA, with an additional amino side chain, PL was integrated with PA to develop multifunctional nanofibers. This study explores a simple, scalable method by which to obtain PL nanofibers by utilizing the structurally similar PA as the base. The goal was to enhance the functionality of PA by addressing its drawbacks. The study demonstrates spinnability of varying concentrations of PL with base PA while exploring compositions with higher PL concentrations than previously reported. Electrospinning parameters were studied to optimize the nanofiber properties. The effects of PL addition on morphology, hydrophilicity, thermal stability, mechanical performance, and long-term antimicrobial activity of nanofibers were evaluated. The maximum spinnable concentration of PL in PA-based nanofibers resulted in super hydrophilicity (0° static water contact angle within 10 s), increased tensile strength (1.02 MPa from 0.36 MPa of control), and efficient antimicrobial properties with long-term stability. These enhanced characteristics hold promise for the composite nanofiber's application in medical and protective textiles. [ABSTRACT FROM AUTHOR]

Soft tissue adhesion and sealing around dental and maxillofacial implants, related prosthetic components, and crowns are a clinical imperative to prevent adverse outcomes of periodontitis and periimplantitis. Zirconia is often used to fabricate implant components and crowns. Here, we hypothesized that UV treatment of zirconia would induce unique behaviors in fibroblasts that favor the establishment of a soft tissue seal. Human oral fibroblasts were cultured on zirconia specimens to confluency before placing a second zirconia specimen (either untreated or treated with one minute of 172 nm vacuum UV (VUV) light) next to the first specimen separated by a gap of 150 µm. After seven days of culture, fibroblasts only transmigrated onto VUV-treated zirconia, forming a 2.36 mm volume zone and 5.30 mm leading edge. Cells migrating on VUV-treated zirconia were enlarged, with robust formation of multidirectional cytoplastic projections, even on day seven. Fibroblasts were also cultured on horizontally placed and 45° and 60° tilted zirconia specimens, with the latter configurations compromising initial attachment and proliferation. However, VUV treatment of zirconia mitigated the negative impact of tilting, with higher tilt angles increasing the difference in cellular behavior between control and VUV-treated specimens. Fibroblast size, perimeter, and diameter on day seven were greater than on day one exclusively on VUV-treated zirconia. VUV treatment reduced surface elemental carbon and induced superhydrophilicity, confirming the removal of the hydrocarbon pellicle. Similar effects of VUV treatment were observed on glazed zirconia specimens with silica surfaces. One-minute VUV photofunctionalization of zirconia and silica therefore promotes human oral fibroblast attachment and proliferation, especially under challenging culture conditions, and induces specimen-to-specimen transmigration and sustainable photofunctionalization for at least seven days.

High heat generation is the main problem that sophisticated electronic devices can suffer. The pool boiling process can offer an excellent heat dispassion at constant temperatures. Therefore, it is one of the most powerful cooling processes used in nuclear power plants, data centers, air conditioning, etc. Because of that, enhancing pool boiling has become a goal of many recent investigations. The current paper presents an experimental study to evaluate the effect of nano and nanocomposite coating on the performance of pool boiling of deionized water under atmospheric pressure. Four surfaces made of copper were used in this study: smooth, CNT (1 g), GNPs (1 g), and (CNT-GNPs (1:1) g) surfaces. A four-step electro-deposition method was used to fabricate a nickel coating using the abovementioned materials. The variation in coating materials offers different surface wettability and roughness to the fabricated surfaces. The experiment's outcome revealed that the hydrophilic material can enhance the critical heat flux (CHF). The mixed wettability obtained by the nanocomposite coating can improve the heat transfer coefficient (HTC). Maximum enhancement in the CHF is obtained by GNPs (1 g) surface with 102%, while the maximum HTC is obtained by (CNT-GNPs (1:1) g) surface with 154% when it is compared with the plain surface.

In this work, a simple and one-step process was demonstrated to develop hydrophobic polymer surfaces. Commercially available polycarbonate (PC) was treated to turn the front surface hydrophobic with an average wetting contact angle (WCA) as high as 110.5°. The formation of micro-flowers with a coverage density of 9.29 × 106/cm2 on the top of fine base nanostructures was confirmed by a high-resolution field emission scanning electron microscope (FESEM). Impact of typical metal and metal oxide such as silver (Ag) and tungsten oxide (WO3) deposited on such hydrophobic surfaces was demonstrated. Petals of micro-flowers and fine base nanostructures were well decorated with functional metals such as Ag and thus the front surface remained hydrophobic with an average WCA as high as 106.6°. Abundant sharp spikes on the top of narrow hills and dips as revealed in the high-resolution FESEM investigation, were speculated to be the reason behind this hydrophobic characteristic. On the other hand, the hydrophobic surface (WCA of ∼ 110.5°) turned hydrophilic (WCA of ∼11.7°) when the surface was decorated with functional metal oxides, such as WO3. Sessile drop tests were carried out to record average WCA and to understand the wetting characteristics of the specimens. A plausible mechanism for such hydrophobic characteristics as well as the transition from a hydrophobic state to a hydrophilic state has been elucidated.

[Display omitted] Water splitting is a promising technique for clean hydrogen production. To improve the sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), the development of efficient bifunctional electrocatalysts for both HER and OER is urgent to approach the scale-up applications of water splitting. Nowadays transition metal oxides (TMOs) are considered as the promising electrocatalysts due to their low cost, structural flexibility and stability, however, their electrocatalytic activities are eager to be improved. Here, we synthesized waxberry-like hydrophilic Co-doped ZnFe 2 O 4 electrocatalysts as bifunctional electrocatalysts for water splitting. Due to the enhanced active sites by electronic structure tuning and modified super-hydrophilic characteristics, the spinel ZFO-Co 0.5 electrocatalyst exhibits excellent catalytic activities for both OER and HER. It exhibits a remarkable low OER overpotential of 220 mV at a current density of 10 mA cm−2 and a Tafel slope of 28.2 mV dec-1. Meanwhile, it achieves a low overpotential of 73 mV at a current density of 10 mA cm−2 with the Tafel slope of 87 mV dec-1 for HER. In addition, for water electrolysis device, the electrocatalytic performance of ZFO-Co 0.5 ||ZFO-Co 0.5 surpasses that of commercial IrO 2 ||Pt/C. Our work reveals that the hydrophilic morphology regulation combined with metallic doping strategy is a facile and effective approach to synthesize spinel TMOs as excellent bifunctional electrocatalyst for water splitting. [ABSTRACT FROM AUTHOR]

The main target of this research is to allow solar PV to contribute economically to an on-grid energy-efficient building where the dust accumulation is a significant factor. Self-cleaning coatings such as hydrophobic or hydrophilic materials have recently been introduced to reduce dust deposition on building-integrated PV (BIPV) panels. The hydrophilic Nano-coated material is examined as a solution to decrease the impact of the dust on the BIPV panels and harvest more solar energy. An impartial comparison of the BIPV panels performance under natural dust conditions, manual cleaning, and hydrophilic nanomaterial coating is performed. Through an exhaustive and qualitative experimental analysis, the anti-reflection and anti-static properties of the utilized Nano-coated material are examined. The experimental results show that the hydrophilic Nano-coated material significantly improves the gathered maximum output power by 18% compared to the manually wiped panel. The calculated efficiencies of the Nano-coated, manual cleaning, and dusty panels are 11%, 9%, and 6%, respectively, which highlights the futureproofing of the Nano-coated solar panel. Compared to the dusty panels, the ecological and economical results show that the BIPV carbon emissions are desirably dropped by 11% while using Nano-coated PV panels and the payback period is reduced to 3.9 years, which is approximately 12.8% faster.

Abstract The stability of soil organic matter (SOM) that governs soil organic carbon (SOC) storage depends on its characteristics and components, but little is known about how tree species in forest ecosystems affect SOM components and characteristics. In this study, we used FTIR spectroscopy to investigate plantations of two ecologically and economically significant tree species—namely, spruce (Picea spp.) and sycamore (Acer pseudoplatanus)—in order to determine how the different litter inputs and root-microbe interactions of these two plantations affect the functional groups, components, and characteristics of their SOM. Soil samples were taken from the topsoil (0–10 cm) and subsoil (10–20 cm). In the 0–10 cm soil depth, the SOM's hydrophilic, hydrophobic, and aromatic components differ between the spruce and sycamore plantations. The hydrophobic components constitute the primary constituents of the SOM of the two forest plantations, in contrast to the expected predominance of the hydrophilic component of the SOM. Also, the high hydrophobicity (hydrophilic/hydrophobic) in the subsoil of the spruce plantations was attributed to a decrease in hydrophilic components and a subsequent increase in hydrophobic components of the SOM. The sycamore plantations exhibited a higher SOM aromaticity and a greater degree of decomposition than the spruce plantations. The aforementioned distinctions emphasise the contrasting mechanisms involved in transforming and turnover of the two-tree species' soil organic matter (SOM).

Antibacterial materials with high hydrophobicity have drawbacks such as protein adsorption, bacterial contamination, and biofilm formation, which are responsible for some serious adverse health events. Therefore, antibacterial materials with high hydrophilicity are highly desired. In this paper, UV‐curable antibacterial materials are prepared from silicone−containing Choline chloride (ChCl) functionalized hyperbranched quaternary ammonium salts (QAS) and tri−hydroxylethyl acrylate phosphate (TAEP). The materials show high hydrophilic performance because their water contact angle is as low as 19.3°. The materials also exhibit quite high antibacterial efficiency against S. aureus over 95.6%, fairly high transmittance over 90%, and good mechanical performance with tensile strength as high as 6.5 MPa. It reveals that it is a feasible strategy to develop antibacterial materials with low hydrophobicity from silicone‐modified ChCl‐functionalized hyperbranched QAS. [ABSTRACT FROM AUTHOR]

Aluminum alloy 2024 is the most widely used metal alloy in aircraft due to its superior characteristics. Although the effects of surface chemistry and topography on the wettability transition have been investigated in the literature, it has not yet been clarified which mechanism is more dominant. In this study, the super-hydrophobic Al2024 sample surfaces were obtained over time in a single step using a nanosecond pulsed fiber laser. Different micro- and nano-structures were produced by changing the laser output power and scanning speed. The effects of laser parameters on the wettability of the Al2024 samples were examined. As with the untreated sample, all fresh laser-treated samples have a hydrophilic or super-hydrophilic surface property. It was found that the fresh laser-treated aluminum alloy surfaces were super-hydrophilic. Then, the Al2024 samples were exposed to ambient air for a certain period. It was found that the contact angles (CAs) of all laser-treated Al2024 samples increased over time. Also, the water drop moved away from the surface of some super-hydrophobic samples at angles of less than 10°. With more than 150° water contact angle and less than 10° sliding angle, it was proved that the lotus effect was obtained at various time scales. The icing properties of the lotus sample were investigated. The surface icing characteristics of the lotus sample have been improved. The XPS high resolution analyses show that the Al-C bond could be responsible for the wettability transition of the laser-ablated samples from hydrophilic to super-hydrophobicity (lotus). [ABSTRACT FROM AUTHOR]

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The main target of this research is to allow solar PV to contribute economically to an on-grid energy-efficient building where the dust accumulation is a significant factor. Self-cleaning coatings such as hydrophobic or hydrophilic materials have recently been introduced to reduce dust deposition on building-integrated PV (BIPV) panels. The hydrophilic Nano-coated material is examined as a solution to decrease the impact of the dust on the BIPV panels and harvest more solar energy. An impartial comparison of the BIPV panels performance under natural dust conditions, manual cleaning, and hydrophilic nanomaterial coating is performed. Through an exhaustive and qualitative experimental analysis, the anti-reflection and anti-static properties of the utilized Nano-coated material are examined. The experimental results show that the hydrophilic Nano-coated material significantly improves the gathered maximum output power by 18% compared to the manually wiped panel. The calculated efficiencies of the Nano-coated, manual cleaning, and dusty panels are 11%, 9%, and 6%, respectively, which highlights the futureproofing of the Nano-coated solar panel. Compared to the dusty panels, the ecological and economical results show that the BIPV carbon emissions are desirably dropped by 11% while using Nano-coated PV panels and the payback period is reduced to 3.9 years, which is approximately 12.8% faster. [ABSTRACT FROM AUTHOR]

Microneedles are extensively used in the field of drug deliveries and disease treatment. Cellulose porous microneedles were fabricated using the cellulose acetate phase separation method followed by a deacetylation process. The developed cellulose microneedles were tested for porosity, mechanical strength, penetration, and surface hydrophobicity. The porosity of cellulose microneedles increased by approximately 15%, while the Young's modulus, indicative of mechanical strength, increased by approximately 30% compared with cellulose acetate microneedles before the deacetylation process. The cellulose microneedles easily penetrated the sample skin, making it a potential tool for transdermal drug delivery. The developed cellulose microneedles exhibited enhanced hydrophilicity in comparison to cellulose acetate microneedles. The increased hydrophilicity of the developed microneedles positions them as promising tools for efficient interstitial fluid extraction. These characteristics not only make them suitable for drug delivery but also highlights their potential as biosensors. [ABSTRACT FROM AUTHOR]

In this study, lead(II) sulphide (PbS) nanoparticles of varying particle sizes were synthesized using the hot injection method, employing 1-octadecene (ODE) as a coordinating ligand in conjunction with oleylamine (OAm). This synthesis approach was compared with the preparation of hexagonal-shaped nanoparticles through the ligand of 1-Dodecanethiol (DT), resulting in DT-capped PbS nanoparticles. The prepared nanoparticles were characterized using multiple techniques including photoluminescence (PL), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). The condensation reaction of DT ligands led to various nanoparticles within the range of 34.87 nm to 35.87 nm across different synthesis temperatures (120 °C, 150 °C, 180 °C, 210 °C, and 240 °C). The PbS with DT ligands exhibited a highly crystalline and superhydrophilic structure. Interestingly, near-infrared (NIR)-PL analysis revealed peaks at 1100 nm, representing the lowest-energy excitonic absorption peak of PbS nanoparticles for both ligands. This suggests their potential utility in various applications, including IR photoreactors, as well as in the development of non-toxic nanoparticles for potential applications in in vivo bioimaging. [ABSTRACT FROM AUTHOR]

We have investigated a simple two-step method for the hydrophilic modification of polycarbonate using polyethyleneimine (PEI) and poly(acrylic acid-co-maleic acid) (PAcM). While PEI or PAcM can improve the hydrophilicity, much better hydrophilicity is obtained by treating polycarbonate with PEI and then PAcM. While a higher treating temperature generally leads to a lower contact angle, the reaction time does not play an important role (e.g., between 15 and 90 min). Meanwhile, increasing the concentration of PEI or PAcM can generate better hydrophilicity. Superhydrophilicity is obtained with a contact angle of 3° while maintaining the transparency of polycarbonate. [ABSTRACT FROM AUTHOR]

This study employs potassium ferrate (K2FeO4) for the oxidation treatment of multi‐walled carbon nanotubes (MWNTs) under neutral and acidic conditions. A wet flash evaporation process is utilized to prepare natural rubber/MWNTs/carbon black composites, enhancing the performance of rubber composites. The increased oxidation level of MWNTs enhances their hydrophilicity, increases the quantity of oxygen‐containing hydroxyl groups on the surface, promotes dispersion within the natural rubber matrix, and ultimately improves the performance of the rubber products. The effective dispersion of MWNTs reduces electron transport resistance, forming a favorable electron transport channel in natural rubber. Experimental results indicate that K2FeO4 achieves the highest oxidation degree and optimal performance in an acidic environment. Compared to untreated MWNTs rubber composites, the oxidized MWNTs rubber composites exhibit a 34.9% reduction in the Payne effect, a 15.7% decrease in wear, a 12.7% reduction in rolling resistance, and a two‐order‐of‐magnitude increase in conductivity. This study provides a novel approach for preparing water‐dispersible MWNTs and high‐performance rubber composites, holding potential applications in premium rubber products and conductive rubber fields. Highlights: The wet flash refining process improved the dispersion of MWNTs.K2FeO4 oxidation of MWNTs was enhanced under acidic conditions.Oxidized MWNTs combined with CB to form a CB‐MWNTs‐CB filler network.Oxidized MWNTs and CB increased the "ball‐chain" arrangement in NR. [ABSTRACT FROM AUTHOR]

The stability of soil organic matter (SOM) that governs soil organic carbon (SOC) storage depends on its characteristics and components, but little is known about how tree species in forest ecosystems affect SOM components and characteristics. In this study, we used FTIR spectroscopy to investigate plantations of two ecologically and economically significant tree species—namely, spruce (Picea spp.) and sycamore (Acer pseudoplatanus)—in order to determine how the different litter inputs and root-microbe interactions of these two plantations affect the functional groups, components, and characteristics of their SOM. Soil samples were taken from the topsoil (0–10 cm) and subsoil (10–20 cm). In the 0–10 cm soil depth, the SOM's hydrophilic, hydrophobic, and aromatic components differ between the spruce and sycamore plantations. The hydrophobic components constitute the primary constituents of the SOM of the two forest plantations, in contrast to the expected predominance of the hydrophilic component of the SOM. Also, the high hydrophobicity (hydrophilic/hydrophobic) in the subsoil of the spruce plantations was attributed to a decrease in hydrophilic components and a subsequent increase in hydrophobic components of the SOM. The sycamore plantations exhibited a higher SOM aromaticity and a greater degree of decomposition than the spruce plantations. The aforementioned distinctions emphasise the contrasting mechanisms involved in transforming and turnover of the two-tree species' soil organic matter (SOM). [ABSTRACT FROM AUTHOR]

This study explores the ion transport properties of self‐microporous polymers by introducing a novel combination of carboxylated PIM‐1 with sulfonated graphene oxide (SGO) to fabricate membranes. The resulting membranes exhibit enhanced structural stability, hydrophilicity, and ion exchange capacity (IEC) compared with the original carboxylated PIM‐1 (CPIM‐1), while preserving the subnanoporous structure. However, it was observed that excessive SGO loading leads to a detrimental "blocking effect" that compromises various membrane properties. Through electrically driven ion transport tests in a 0.01 M NaCl solution, it is demonstrated that a moderate amount of SGO effectively enhances membrane conductivity from 46.96 μS m−1 (for carboxylated PIM‐1 membranes without SGO) to 56.55 μS m−1. Additionally, the membranes exhibit selective sieving of cations and anions. The presence of small‐sized ion channels and the electrostatic repulsion generated by the abundant carboxyl and sulfonic acid groups significantly hinder Cl− transport. Consequently, the Na+/Cl− migration ratio (t+/t−) reaches 98 at a concentration ratio of 10:1 on both sides of the membrane, surpassing the value of 3.74 observed for the pure CPIM‐1 membrane. This investigation provides valuable insights for the practical application of easily prepared, processable, and cost‐effective hydrophilic self‐contained microporous polymer membranes in ion transport applications. [ABSTRACT FROM AUTHOR]

Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. Thrombosis is fundamentally initiated by the nonspecific adsorption of proteins to the material surface, which is strongly governed by thermodynamic factors established by the nature of the interaction between the material surface, surrounding water molecules, and the protein itself. Along these lines, different surface materials (such as polymeric, metallic, ceramic, or composite) induce different entropic and enthalpic changes at the surface–protein interface, with material wettability significantly impacting this behavior. Consequently, protein adsorption on medical devices can be modulated by altering their wettability and surface energy. A plethora of polymeric coating modifications have been utilized for this purpose; hydrophobic modifications may promote or inhibit protein adsorption determined by van der Waals forces, while hydrophilic materials achieve this by mainly relying on hydrogen bonding, or unbalanced/balanced electrostatic interactions. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications. Blood-contacting medical devices often succumb to thrombosis, limiting their durability and safety in clinical applications. A plethora of polymeric coating modifications have been utilized for addressing this issue. This review offers a cohesive understanding of the thermodynamics governing these phenomena, to specifically aid in the design and selection of hemocompatible polymeric coatings for biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The anti-corrosion performance and biocompatibility of developed bioactive polypyrrole (PPy)-coated titanium (Ti) have been studied in the present work. Coating of PPy on Ti was performed by the electropolymerization technique using various concentrations of pyrrole in an aqueous solution. 13C solid NMR, ATR-FTIR and Raman spectroscopy analysis confirmed the presence of PPy over Ti metal. The morphology of PPy-coated substrates revealed a cauliflower-like structure with a high roughness value. Wettability studies showed the hydrophilic property of the PPy-coated Ti metal compared to uncoated Ti. The increased polarization resistance (Rp) and reduced corrosion current density (icorr) results exhibit improved protection ability for the PPy-coated Ti. Bode impedance and phase angle values were high for the PPy-coated substrate compared to uncoated Ti. Apatite formation on the coated substrate was higher after 7 days of immersion in simulated body fluid (SBF) solution. Cell culture studies result revealed that PPy-coated surface enhances the adhesion of MG-63 cells on titanium surface and also improve the bone-forming ability. [ABSTRACT FROM AUTHOR]

Aims: Desvenlafaxine (DES) in conventional dosage forms shows initial burst release after oral administration, leading to exaggeration of its side effects. These side effects can be overcome by a sustained-release dosage form using the chemically inert, low-melting-point lipid Compritol® 888 ATO, as it reduces initial burst release. Materials & methods: The potential of DES-loaded solid lipid nanoparticles (DES-SLNs) synthesized by ultrasonication-assisted hot-melt encapsulation to modify the release of DES was investigated. Results: The entrapment efficiency of DES-SLNs was 65.90% with the in vitro release profile showing a sustained-release behavior achieving 81% cumulative release within 16 h without initial burst release. Conclusion: DES-SLNs are a potential carrier for sustained release of water-soluble antidepressant drugs such as DES. Summary points Desvenlafaxine (DES) is a hydrophilic drug showing initial burst release from conventional dosage forms. It is rapidly absorbed after its oral administration, which intensifies its side effects. Its burst release was overcome by incorporating it into Compritol-based solid lipid nanoparticles (SLNs). DES-SLNs prepared by the hot-melt encapsulation technique had a particle size of 156 nm with an encapsulation efficiency of 69.50% and appeared spherical with a smooth surface when observed under a scanning electron microscope. The DES-SLNs had a polydispersity index value of 0.139, indicative of homogenous dispersion. x-ray diffraction analysis revealed the conversion of DES from crystalline form to amorphous form, exhibiting molecular dispersion of the DES in the Compritol matrix. An in vitro release study of DES presented a sustained release of drug from lipid matrix with no initial burst release that is observed in commercially available tablets of DES. [ABSTRACT FROM AUTHOR]

The accumulation of microorganisms, algae, mussels, and barnacles on the hull of sea vessels leads to biofouling, surface corrosion, and increased drag as the vessel moves through water costing the marine industry around $15 billion/year. Current commercial traditional antifouling coatings suffer from reduced energy efficiency and short lifespan and contain heavy metals that are toxic to marine organisms and humans. The banning of these coatings is due to environmental concerns, and nonbiocidal alternatives such as polymer-based coatings are being sought after. This review demonstrates emerging promises of hydrogel fouling-release coatings (FRCs) in the marine environment that may be effective against a prevalent amount of biofouling agents. The review also highlights the importance of polymer backbone materials with surface wettability characteristics possessing hydrophobic, hydrophilic, and zwitterionic properties and further discusses emerging antifouling techniques, synthesis of hydrogel, swelling behavior of hydrogel, laboratory assays of hydrogel coating, marine field test, and outlook of hydrogel fouling-release (FRCs) coatings. [ABSTRACT FROM AUTHOR]

The present studies shed light on the continuum breakdown of water confined in nanotubes of different materials and diameters. The structure and hydrodynamics of water confined in nanotubes of carbon (CNT), boron nitride (BNNT), silicon carbide (SiC), and silicon nitride (SiNT) of different chirality indices were analyzed to examine the potential nanomembrane material for water purification. According to our findings of the contact angle with water, BNNTs are more hydrophobic than CNTs, and silica nanotubes are hydrophilic. The higher permeability of water was observed through CNTs and BNNTs in comparison to silica nanotubes. Nearly flat velocity profiles indicated continuum breakdown at the nanoscale. Also, the trend for viscosity and diffusion coefficient did not follow the Stokes–Einstein relation, indicating continuum breakdown. The results demonstrated the connectivity of microscopic diffusion with the macroscopic permeation flux, which might be important information for the theoretical investigation of the suitable operational regime in reverse osmosis. Essentially, the continuum breakdown due to freezing of water was seen to be diminished with an increase in temperature. The results showed characteristic changes in the density profile, diffusion coefficient, velocity autocorrelation functions, density of state functions, and thermodynamic entropic components (evaluated using the two-phase thermodynamic method) of permeating water molecules. Importantly, our results reflect that the continuum breakdown observed for water confined in smaller nanotubes is true only at temperatures below 400 K due to the ice-like dense structure of water molecules. Once the entering water molecules can gain energy to compensate for the loss of H bonds, the conventional fluid dynamics relations can be well applied to estimate the hydrodynamics of confined water. [ABSTRACT FROM AUTHOR]

Surface functional groups (SFGs) play a key role in adsorption of any target molecule and CO2 is no exception. In fact, due to its quadrupole nature, different SFGs may attract either the oxygen or the carbon atoms to facilitate improved sorption characteristics in porous materials, hence the proliferation of this approach in the context of carbon capture via solid adsorbents. However, actual processes involve CO2 capture/removal from a mixed gas stream that may have a non-negligible water content. The presence of humidity significantly hampers the sorption properties of classical physisorbents. To overcome this, the surface of the adsorbent can be modified to include hydrophobic/hydrophilic SFGs making the materials more resilient to moisture. However, the mechanisms behind H2O-tolerance depend greatly on the characteristics of SFGs themselves. Herein, a multitude of hydrophobic and hydrophilic SFGs (e.g. carbonyls, halogens, hydroxyls, nitro groups, phenyls, various alkyl chains and etc.) for physical CO2 adsorption are reviewed within the context of their separation performance in a humid environment, highlighting their merits and limitations as well as their impact on cooperative or competitive H2O – CO2 adsorption.

Wetting functionalities of rough surfaces are largely determined by the Laplace pressure generated across liquid–gas interfaces formed within surface structures. Typically, rough wetting surfaces create negative Laplace pressures, enabling capillary wicking, while rough non-wetting surfaces create positive Laplace pressures, exhibiting fluid repellency. Here, with microfabricated reentrant structures, it is shown that the same surface can exhibit either a negative or positive Laplace pressure, regardless of its intrinsic wettability. This material-independent Laplace pressure duality enables or enhances a range of wetting functionalities including wicking, switchability, and selectivity. On the same surface, capillary rise, capillary dip, and the combination of the two which leads to further enhancement of the total sustainable capillary height and Laplace pressure, the driving force for wicking is demonstrated. Further, active switching of wetting states between the hemiwicking and the repellent Cassie state on reentrant structures is shown. Moreover, with a water-hexane mixture system, selective wetting of reentrant structures are demonstrated, that is, water can be selectively wicked or repelled in the presence of hexane, and vice versa. These functionalities are achieved, which would typically require complex chemical coatings, solely using surface structures, thus largely expanding the design space for a wide range of thermofluidic applications.

A 54-year-old man with noncontributory medical history presented to an ophthalmologist in January 2022 after 10 days of irritation in his right eye. The patient recounts having felt something get into his eye and under his contact lens (CL) while he was climbing into his car, but he was unsure what the foreign body may have been. Initial examination by the clinician found uncorrected distance visual acuity of 20/100-2 with a corneal abrasion, 4+ corneal edema, and 3+ conjunctival injection, for which he was placed on topical antibiotics (ocuflox and tobradex) with a bandage CL. 1 week later, visual acuity was 20/80, corneal edema had improved, and he was noted to have corneal scarring and an epithelial defect. Tobradex was continued while prednisolone drops and preservative-free artificial tears were started. 1 week later, the patient had worsening visual acuity to 20/250 and was referred to our tertiary center. On initial consultation, the patient had an uncorrected distance visual acuity of 20/500 and an uncorrected near visual acuity of >J10 in the right eye. Slitlamp examination of the right eye was significant for vortex keratopathy and mild corneal pannus with 360-degree subtle conjunctivalization of the limbus ( Figure 1JOURNAL/jcrs/04.03/02158034-202210000-00022/figure1/v/2022-10-03T121249Z/r/image-tiff ). The corneal topograph was obtained showing significant surface irregularity on the Placido image ( Figure 2JOURNAL/jcrs/04.03/02158034-202210000-00022/figure2/v/2022-10-03T121249Z/r/image-tiff ). Examination of the left eye was unremarkable. The ocular history is significant for myopia of -4.0 diopters and CL use for 20 years. The patient admits to regularly wearing soft CLs for several days straight and only removing them for a few hours. Antibiotics were discontinued, corticosteroid drops were reduced in frequency, and the patient was continued on preservative-free artificial tears. What imaging might you consider? What is your differential diagnosis at this point? What would be the most appropriate surgical and/or medical interventions? What would you counsel in prognosis for this patient?

The rise in oil spill incidents has led to a surge in environmental and ecological issues, making it crucial to create efficient oil-cleaning materials. Green approaches to address various aquatic pollution nowadays is the most important subject of environmental remediation. Among the available options, aerogel material stands out due to its low density, high porosity, and exceptional surface area, making it a remarkable choice for oil–water separation. Nonetheless, the usage of aerogels is limited by their low strength and flexibility, which hinder their application. In this study, strong alginate aerogel fibers reinforced with cotton have been synthesized with 88% porosity, 123 nm average pore size, and 0.24 g cm−3 density using a wet spinning technique followed by freeze-drying for the separation of oil/water mixtures. The morphology, chemical, and microstructural characterization of the prepared alginate aerogel fibers were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. These characterization results demonstrated the three-dimensional porous, rough structure of aerogel fibers and cotton fibers are successfully incorporated into the aerogel fiber structure. Single fiber strength tester indicated that the addition of cotton increased the strength from 2 to 16 cN of aerogel fibers but decreased the elongation. The prepared alginate aerogel fibers showed good oleophobicity underwater and excellent oil/water separation efficiency (up to 99.4%). Therefore, synthesized aerogel fiber with ease of fabrication and excellent separation of oil/water mixture is a promising candidate for commercial applications in water filtration. [ABSTRACT FROM AUTHOR]

This research aims to prepare liquid fertilizer beads formed with sodium alginate (SA) (SAB) that were coated with interpenetrating polymer network (IPN) hydrogels based on pre-vulcanized natural rubber latex (NR) and cassava starch (St) (IPN NR/St) for controlling the release of the urea solutions. The preparation of SAB at various concentrations of SA and calcium chloride (CaCl2) solutions was investigated. Optimal concentrations were determined to be 1.5% and 5.0 wt% for SA and CaCl2, respectively. Subsequently, the obtained SAB underwent coating with IPN NR/St, utilizing a ratio of 1.0/1.0 between SAB and IPN NR/St, with two layers of coating. The resulting coated alginate beads (CSAB) exhibited the ability to slow down the release of urea solution, contributing to enhanced growth in Thai eggplants. Beyond efficient urea release control, CSAB presents advantages in mitigating environmental issues associated with traditional fertilizers. The study proposes CSAB as an innovative technique for the coating and controlled liquid release of organic or biofertilizers. The potential benefits extend to promoting sustainable agriculture practices while addressing environmental concerns, marking CSAB as a promising solution for organic and biofertilizer applications. [ABSTRACT FROM AUTHOR]

In geo-environmental applications, the potential of biochar has been explored as a suitable cover material of landfill and vegetated slopes. The inherent nature of biochar affects the geo-environmental properties of the soil-biochar composite like water retention, compressive strength, infiltration, and soil erosion. Performance of a cover depends on biochar's surface functional groups, which can be either hydrophobic or hydrophilic based on bio-source. The objective of this paper is to investigate the geotechnical properties of biochar-amended soil sourced from two contrasting feedstock, i.e., poultry litter (animal based) and water hyacinth (plant based). The test results show that biochar addition increased the Atterberg limits and reduced the acidity of soil. Biochar addition directly increased the optimum moisture content and decreased the maximum dry density. Both biochar addition decreased the composite compressive strength by 25–50% but increased the ductility of composite. Water hyacinth biochar (WHB) inclusion decreased the erosion rate of soil while it is not the same for poultry litter biochar (PLB). In the case of water retention, only the addition of WHB increases retention and holding capacity of soil. The obtained results have been discussed in context with the conducted microstructural, chemical, and physical tests on both biochar. Through these analyses on biochar of different origin and having contrasting functional groups and intra-pore network, the development of a complex biochar-water network was confirmed. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) has been used in a variety of lubrication products due to its highly tunable surface chemistry. However, the performance of MoS2-derived tribofilms falls short when compared to other commercially available antiwear additives. The primary objective of this study is to improve the tribological performance of MoS2 as an additive for lithium-based greases. This was achieved by functionalizing the particle with hydrophilic molecules, such as urea. Experimental results indicate that the urea-functionalized MoS2 (U-MoS2) leads to a notable decrease in the coefficient of friction of 22% and a substantial reduction in the wear rate of 85% compared to its unmodified state. These results are correlated with the density functional theory (DFT) calculation of U-MoS2 to theorize two mechanisms that explain the improved performance. Urea has the capability to reside both on the surface of MoS2 and within its interlayer spacing. Weakened van der Waals forces due to interlayer expansion and the hydrophilicity of the functionalized U-MoS2 surface are catalysts for both friction reduction and the longevity of tribofilms on hydrophilic steel surfaces. These findings offer valuable insights into the development of a novel class of lubricant additives using functionalized hydrophilic molecules. [ABSTRACT FROM AUTHOR]

Shrink film is a thin sheet of polystyrene plastic that shrinks to 25–40% of its original size when heated. This study investigated the shrinkage factor of the film at different temperatures and baking times to determine the optimal fabrication recipe for shrink film microfluidic device production. Additionally, this study characterized the properties of shrink film, including minimum possible feature size and cross-section geometries, using manual engraving and the CAMEO 4 automated cutting machine. The optimal shrinkage factor ranged from 1.7 to 2.9 at 150 °C and a baking time of 4 min, producing the ideal size for microfluidic device fabrication. The X- and Y-axes shrank ~2.5 times, while Z-axis thickened by a factor of ~5.8 times. This study achieved a minimum feature size of 200 microns, limited by the collapsing of channel sidewalls when shrunk, leading to blockages in the microchannel. These findings demonstrate the feasibility and versatility of using shrink film as a cost-effective and efficient material for the rapid fabrication of microfluidic devices. The potential applications of this material in various fields such as the medical and biomedical industries, bacteria and algae culture and enumeration are noteworthy. [ABSTRACT FROM AUTHOR]

Injuries and damage to the skin can be caused by different reasons throughout human life. The use of sodium alginate in tissue dressing has been highly studied due to its intrinsic properties, including its degradation rate and biocompatibility, and the capacity of supporting tissue proliferation. The aim of this paper is to demonstrate evidences, through a systematic review method, to support the application of sodium alginate as a curative and as a potential accelerator in the healing of skin wounds. Four databases were used to develop this systematic review: Science Direct, PubMed, Scielo and Scopus. The time interval established for the search was from January 2016 to October 2023. After applying the exclusion and inclusion criteria, each selected article was evaluated and it was observed that the improvement of the mechanical properties of sodium alginate when correctly processed and crosslinked were evident. However, the increase of crosslinking affects as the wettability and the swelling of the biomaterials can cause limitations in mechanical properties and hidrophilic behavior. To achieve the ideal dressing, it is necessary to apply the optimal concentration of crosslinking and other substances, which can damage its hidrophilic characteristic. Thus, it was concluded that sodium alginate has every caracteristic desirable to develop an effective and safe dressing. [ABSTRACT FROM AUTHOR]

Surface wettability plays a significant role in reducing solid-liquid frictional resistance, especially the superhydrophilic/hydrophilic interface because of its excellent thermodynamic stability. In this work, poly(acrylic acid)-poly(acrylamide) (PAA–PAM) hydrogel coatings with different thicknesses were prepared in situ by polydopamine (PDA)-UV assisted surface catalytically initiated radical polymerization. Fluid drag reduction performance of hydrogel surface was measured using a rotational rheometer by the plate-plate mode. The experimental results showed that the average drag reduction of hydrogel surface could reach up to about 56% in Couette flow, which was mainly due to the interfacial polymerization phenomenon that enhanced the ability of hydration layer to delay the momentum dissipation between fluid layers and the diffusion behavior of surface. The proposed drag reduction mechanism of hydrogel surface was expected to shed new light on hydrogel-liquid interface interaction and provide a new way for the development of steady-state drag reduction methods. [ABSTRACT FROM AUTHOR]

Water swellable rubber (WSR) was prepared from epoxidized natural rubber (ENR) and sodium acrylate (NaAA) by in‐situ polymerization using sulfur and dicumyl peroxide (DCP) as a vulcanizing agent and an initiator, respectively. The ENR, NaAA, and other additives were mixed in an internal mixer and a two‐roll mill. The effect of the vulcanization system, epoxide, and DCP, and NaAA content on the vulcanization, physical, and mechanical properties of WSR were investigated in this research. As the results, the scorch and curing time of WSR compounded with ENR 25 and vulcanized with a mixture of sulfur‐peroxided or mixed vulcanization system were less than other systems. Furthermore, the scorch and curing time decreased with the increase in DCP content. The WSR with ENR 50 vulcanized with DCP (1.5 phr) in the mixing system provided the highest tensile strength. However, the volume change of WSR with the mixing system (WSR/M) was lower than the WSR cured with peroxide (WSR/P). For WSR/P, the tensile strength, hardness, and volume change in water increased with increasing DCP, and NaAA content, while the elongation at break decreased. These results suggest that WSR has the potential for diverse applications, including waterproofing and sealing solutions in civil construction projects. Highlights: Water swellable rubber (WSR) was prepared from epoxidized natural rubber (ENR) and sodium acrylate (NaAA) by in‐situ polymerization using sulfur and dicumyl peroxide (DCP) as a vulcanizing agent and an initiator.The scorch and curing time of WSR compounded with ENR 25 and vulcanized with a mixed vulcanization system were less than those of other systems.During the vulcanization process, ENR 50 can be generated by the ring‐opening of the adjacent epoxide groups more than ENR 25, and the self‐crosslink of ENR 50 was higher than ENR 25.Water swelling and volume change of WSR tended to decrease with increasing epoxide, and DCP content, whereas those properties increased with increasing NaAA content.Tensile strength, elongation at break, and hardness of WSR with the mixing system (WSR/M) were higher than those of WSR with the peroxide system (WSR/P).Swelling and volume change of WSR/P were higher than those of WSR/M. [ABSTRACT FROM AUTHOR]

The widespread use of hydrophilic intraocular lenses (IOLs) in eye surgery, fabricated by poly-2-(hydroxyethyl methacrylate) (PHEMA), has highlighted their calcification as a serious problem, implying that their surgical explantation is a rather risky process. The field of biomaterials has been developing rapidly in recent years, with research interest turning to the development of novel materials which involve either copolymers of PHEMA or protective functional coatings. Graphene coatings are particularly attractive because of their respective unique properties. In the present work, we present the results of the investigation of the development of graphene coatings on hydrophilic IOLs and their subsequent performance with respect to calcification opacification. Hydrophilic IOLs with a water content of 18% by weight were coated with graphene oxide (GO) by equilibration with GO suspensions in water. The concentrations of the suspensions ranged from 1 × 10−4 to 20 × 10−4% w/v. The GO suspensions were equilibrated with the IOLs for 5 days at a constant temperature, 37 °C, and rotated in 30 mL tubes end over end. This treatment resulted in the formation of a uniform coating of GO on the IOLs verified by scanning electron microscopy (SEM) and other physicochemical methods. The contact angle of the GO-coated IOLs decreased significantly in comparison with the uncoated IOLs. The GO-coated IOLs exhibited a higher tendency to calcify in supersaturated solutions simulating aqueous humor (SAH). The growth rate of hydroxyapatite (Ca5(PO4)3OH, HAP) on GO-coated IOLs was higher in comparison with the respective untreated IOLs. The conversion of the GO coating via a reduction with phenyl hydrazine resulted in the formation of a reduced-graphene (rGO) surface film, as identified by Raman and XPS spectroscopy. The rGO film was hydrophobic (contact angle 100°) and did not calcify in supersaturated calcium phosphate solutions. [ABSTRACT FROM AUTHOR]

The stability of polymer composite can be enhanced by altering the structure of the functionalised material with surface modifiers, such as silane coupling agents, organic modifiers, surfactants and others. Surfactant has emerged as a potential modifier since it is eco‐friendly and simple. In this study, the surface of functionalised silica (SiO2) was modified using sodium dodecyl sulphate (SDS) in a polyacrylamide (PAM) composite. Characterisation of the drilling fluid was examined through Fourier‐transform infrared spectroscopy, surface tension, contact angle and rheological tests. According to the results, FTIR proved that the modification of PAM was successful. However, all modified PAM showed more hydrophilic properties with low surface tension than bare PAM. The rheological properties of all the modified PAM were varied over all the concentrations of SDS. Meanwhile, the rheological properties of the modified PAM were better than that of bare PAM. Due to the synergistic effect between the surfactant and functionalised material involved, the drilling fluid achieved low plastic viscosity in modified PAM. With a flat gel strength and better rheological properties, 0.2 wt% SDS in modified PAM is a great and promising formula in this study. In the future, further investigation can be conducted on bored pile drilling using this formulation. Highlights: Role of sodium dodecyl sulphate (SDS) in silica (SiO2)/polyacrylamide (PAM) composite.Synthesis of bare PAM and modified PAM doped with various concentrations of SDS.Effect of SDS on the surface properties of SiO2/PAM composite.Effect of SDS on the rheological behaviour of SiO2/PAM composite. [ABSTRACT FROM AUTHOR]