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Mask stereolithography 3D printing for zirconia ceramics has attracted increasing attention in the industrial manufacturing due to their advantages of complex shapes, precisely controlled internal structures and fine surface effects. However, high refractive index and expensive equipment cost have always affected its development. Herein, we combine liquid crystal display (LCD) light curing 3D printing with zirconia molding, which is free from environmental and price limitations. In the conventional method of operation, the cured layer is bonded to the bottom and cannot be manufactured. We put forward a strategy for optimizing separation process and investigate the mechanism of the separation process in depth for high-quality zirconia ceramics LCD 3D printing. The results show that the controlled adjustment of the surface free energy can achieve a great reduction in the separation force, which enabled the successful printing of zirconia ceramics based on LCD. The effect of physical properties of the separation membrane on the separation process was studied and the solid content and 3D printing parameters of ceramic paste were optimized. When the solid content is 72.5 wt%, high quality zirconia ceramic parts with flexural strength of 255 MPa and relative density of 98.1 % can be obtained. This work provides new ideas for the convenient customization of zirconia ceramics in many fields. [ABSTRACT FROM AUTHOR]

Moisture damage (MD) in bituminous mixtures occurs due to the loss of cohesion in the bitumen or adhesion between the binder and aggregates. The existence of moisture may influence the bonding between aggregates and bitumen, which may affect the moisture susceptibility of the bituminous mix. Therefore, there is a need to understand the bonding-debonding properties and the moisture susceptibility of binders and mixes, at the material selection stage. Surface free energy (SFE) method is one of the proven techniques to quantify the moisture susceptibility of bituminous mixtures, by using contact angle (CA) determination of the component materials of the mix. This study aimed to evaluate the effect of hydrated lime (HL) on the moisture susceptibility of bituminous mixtures, with control (VG30) bitumen and pyro-oil modified bitumen (POMB) having different percentages of pyro oil, using the SFE approach. Also, the study compared the SFE characteristics of VG30 and POMB with and without the optimum content of HL. POMB binders were prepared by the addition of high-density polyethylene (HDPE) pyro oil in percentages of 1, 3, and 5% in a control bitumen. HL was added as 20%, 25%, and 30% by weight of bitumen in VG30 and POMB bitumen. The aggregates used in the study were limestone, basalt, gravel, and their SFE components were directly considered from the literature. The sessile drop method was used to measure the CA of bitumen and, in turn, determine the various SFE parameters using Van Oss–Chaudhury–Good theory. The moisture susceptibility of mixtures with and without HL was evaluated and compared. From the results, the MD resistance of the bituminous mixtures with modified and unmodified bitumen was found to be increased after the optimum of HL, depending upon the type of aggregates used. Basalt has a 27.41%, 23.38%, and 10.48% greater energy ratio (ER) with POMB1/25, POMB3/25, and POMB5/30, respectively, than VG30/30, the highest ER in modified base bitumen. This indicates that HDPE pyro-oil treatment improves MD resistance for basalt. Whereas for limestone and gravel, VG30/30 gives a maximum value of ER as compared to any other combination of HL modified POMB. The ER values would assist highway agencies in selecting the most compatible binder–aggregate combinations. [ABSTRACT FROM AUTHOR]

Surface reconstruction has always been a pain point in the study of short-chain perfluoroalkyl acrylate polymers, and how to maintain the balance between environmental protection and good performance is the key issue. We exploited the high efficiency and selectivity of the reaction between the isophorone di-isocyanate group and the hydroxyl group, and the rigid cyclohexane structure contained in their molecule to efficiently prepare a series of novel fluoro acrylate monomers (IFAM) containing rigid cyclohexane as mesogenic core and their homopolymers (PIFAM) with different lengths of short-chain perfluoroalkyl side chains. Their structures, liquid crystal behavior, thermal properties, surface chemical compositions, surface morphologies, and hydrophobicity were characterized and comparatively studied by FTIR, NMR, XRD, POM, DSC, TGA, XPS, AFM, and static/dynamic contact angle tester and dodecafluoroheptyl methacrylate (DFMA) and its homopolymer as a contrast. The results demonstrated that both the synthesized monomers and homopolymers possessed the expected chemical structures with thermotropic liquid crystalline behavior. Furthermore, the thermal stability and hydrophobicity of the polymers increased with the extension of the fluorocarbon chain length. The incorporation of the mesocrystalline motif and appropriate length of fluoroalkyl tails in the PIFAM polymers would enhance hydrophobic stability, as it promoted the crystallinity of the side chains and limited the structural rearrangement of the fluorocarbon chains. This study offers a straightforward method for synthesizing fluoro acrylate polymers with stable surface properties, highlighting their potential application in hydrophobic coatings. [ABSTRACT FROM AUTHOR]

Titanium and titanium alloys are the prevailing dental implant materials owing to their favorable mechanical properties and biocompatibility, but how roughness dictates the biological response is still a matter of debate. In this study, laser texturing was used to generate eight paradigmatic roughened surfaces, with the aim of studying the early biological response elicited on MC3T3-E1 pre-osteoblasts. Prior to cell tests, the samples underwent SEM analysis, optical profilometry, protein adsorption assay, and optical contact angle measurement with water and diiodomethane to determine surface free energy. While all the specimens proved to be biocompatible, supporting similar cell viability at 1, 2, and 3 days, surface roughness could impact significantly on cell adhesion. Factorial analysis and linear regression showed, in a robust and unprecedented way, that an isotropic distribution of deep and closely spaced valleys provides the best condition for cell adhesion, to which both protein adsorption and surface free energy were highly correlated. Overall, here the authors provide, for the first time, a thorough investigation of the relationship between roughness parameters and osteoblast adhesion that may be applied to design and produce new tailored interfaces for implant materials. [ABSTRACT FROM AUTHOR]

Lignin, one of Earth's most abundant biopolymers, is rich in phenolic and aliphatic functional groups, offering significant potential for chemical modification. Technical lignin, a byproduct of the kraft process, is produced in large quantities annually and can be used to enhance the properties of polymer matrices such as polypropylene (PP). PP, a widely used nonpolar polymer, suffers from low surface free energy, leading to poor adhesion properties. Combining PP with polar, renewable-source polymers like lignin can improve these properties. This study investigates the direct acetylation of kraft lignin (KL) to improve its dispersion in the PP matrix and enhance wettability and adhesion. The acetylation of KL was confirmed through FTIR and DSC analyses. PP and acetylated KL (AKL) were combined and processed via continuous extrusion. The blends' thermal and mechanical properties, lignin dispersion, and wettability were evaluated. Additionally, PP and PP–lignin films were bonded to aluminized biaxially oriented polypropylene (BOPP) for peel tests. Results showed increased surface free energy and improved adhesion, particularly in samples with AKL due to better dispersion. This direct acetylation route significantly enhances PP's surface free energy and adhesion, presenting a sustainable alternative to fossil-based materials and promoting the use of lignin, a renewable and low-cost polymer. [ABSTRACT FROM AUTHOR]

The Arkansas Department of Transportation (ARDOT) Maintenance Division is concerned about the use of certain aggregates in asphalt mixture because of their durability and performance issues. Good performance of the pavements can be ensured by selecting good-quality aggregates along with asphalt binders that can produce compatible aggregate–binder systems. The primary goal of this research was to determine proper asphalt binders and aggregates for the construction of highways in Arkansas. Three performance grade (PG) asphalt binders, namely PG 64-22, PG 70-22, and PG 76-22, prepared from two different crude sources, were investigated. This study also included four types of ARDOT-commissioned aggregates, namely gravel, sandstone, limestone, and dolomite, from four quarries throughout Arkansas. Selected properties of asphalt binders and aggregates (e.g., physical, mechanical, and chemical) were evaluated by performing a series of routine laboratory tests. To evaluate the performance of the asphalt mixtures, work of cohesion, work of adhesion, and boiling resistance tests were conducted. These aggregates, binders, and aggregate–binder systems were ranked based on the properties obtained from laboratory tests. In general, any combination of dolomite or limestone with a stiffer binder such as PG 76-22 or PG 70-22 is expected to be superior to an asphalt mixture with either sandstone or gravel. The outcomes of this research will help highway agencies and pavement professionals in selecting suitable asphalt binders and aggregates for long-lasting pavement construction. [ABSTRACT FROM AUTHOR]

Lignin, one of Earth’s most abundant biopolymers, is rich in phenolic and aliphatic functional groups, offering significant potential for chemical modification. Technical lignin, a byproduct of the kraft process, is produced in large quantities annually and can be used to enhance the properties of polymer matrices such as polypropylene (PP). PP, a widely used nonpolar polymer, suffers from low surface free energy, leading to poor adhesion properties. Combining PP with polar, renewable-source polymers like lignin can improve these properties. This study investigates the direct acetylation of kraft lignin (KL) to improve its dispersion in the PP matrix and enhance wettability and adhesion. The acetylation of KL was confirmed through FTIR and DSC analyses. PP and acetylated KL (AKL) were combined and processed via continuous extrusion. The blends’ thermal and mechanical properties, lignin dispersion, and wettability were evaluated. Additionally, PP and PP–lignin films were bonded to aluminized biaxially oriented polypropylene (BOPP) for peel tests. Results showed increased surface free energy and improved adhesion, particularly in samples with AKL due to better dispersion. This direct acetylation route significantly enhances PP’s surface free energy and adhesion, presenting a sustainable alternative to fossil-based materials and promoting the use of lignin, a renewable and low-cost polymer.

The plasma electrolytic polishing (PEP) process on Q235 low-carbon steel anode in (NH4)2SO4 electrolyte was investigated, and its surface properties under different PEP conditions were evaluated. The surface roughness of PEP samples under different electrolyte concentrations, initial roughness, voltages and treating times were measured. The surface morphologies and compositions of typical PEP samples were analyzed, and their wettability and surface free energy under different polishing times were evaluated. It was found that the near-surface temperature of the steel sample raised quickly with increasing the voltage, and then remained at about 100°C after 200V, which is beneficial to keep the microstructure and mechanical properties of Q235 low-carbon steel. Under the parameters of 3.0wt.% (NH4)2SO4 aqueous solution and applied voltage of 200V, the 8min PEP treatment could reduce the surface roughness of Q235 low-carbon steel from 2.100μm to 0.437μm. In addition, the polishing efficiency was the highest in the initial PEP stage, meanwhile, it also increased with the increase of initial roughness of the sample. After the PEP treatment, the contact angle of water on low-carbon steel decreased, and its surface free energy was slightly reduced. Moreover, the thickness of natural oxide film on Q235 low-carbon steel was reduced by about 30% after 8 min polishing treatment. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of airborne particle abrasion with different particles on the surface free energy, roughness, and biaxial flexural strength of a feldspathic ceramic by comparing it with hydrofluoric acid etching, the standard surface treatment, and polishing. Square-shaped feldspathic ceramic specimens (12 mm × 12 mm × 1.2 mm) were divided into subgroups as airborne particles abraded with alumina (AO3a, AO3b, AO25, AO50a, AO50b, AO90, AO110a, AO110b, AO120a, and AO120b), silica (SO50a, SO50b, SO100, and SO100/200), or nutshell granule (NS100/200), hydrofluoric acid etched, and polished (n = 12). Surface free energy (n = 5), roughness (n = 5), biaxial flexural strength (n = 12), and Weibull moduli (n = 12) were investigated. Data were evaluated with 1-way ANOVA and Tukey HSD tests, and possible correlations were investigated with Pearson's correlation (α = 0.05). SO100/200 mostly had lower surface free energy (p ≤ 0.011), and polishing and etching led to higher surface free energy than AO3a, AO3b, and AO120a (p ≤ 0.031). Polished, SO100, and SO50b specimens mostly had lower roughness and AO125 had the highest roughness (p ≤ 0.029). SO100/200 mostly had lower biaxial flexural strength (p ≤ 0.041), and etched specimens had higher biaxial flexural strength than AO120a, AO120b, and SO50b (p ≤ 0.043). AO3b had the highest (33.56) and AO120b had the lowest (11.8) Weibull modulus. There was a weak positive correlation between the surface free energy and the biaxial flexural strength (r = 0.267, p = 0.011). A larger particle size mostly resulted in higher roughness, which was also affected by the particle shape. Most of the test groups had similar biaxial flexural strength to that of the hydrofluoric acid-etched group. Therefore, for tested feldspathic ceramic, airborne particle abrasion with tested parameters may be a suitable alternative without causing any further damage. [ABSTRACT FROM AUTHOR]

The primary focus of this study is to assess the stripping resistance of bitumen when partially replaced with rice-straw biomass-based lignin from bio-ethanol industry residue. Moreover, the study examines the relationship between the chemical and physicochemical (surface free energy or SFE) properties of lignin-substituted bitumen blends and their stripping potential. Two distinct lignin materials were examined: fermentation residue (FRL), a by-product directly obtained from the bio-ethanol industry, and Isolated Lignin (IL), which was extracted from FRL through an alkali-acid precipitation process. These materials were partially substituted at dosages of 5%, 10%, and 15% by weight of bitumen. Test results indicated that the addition of lignin to bitumen led to a change in SFE, with an increase in the polar component and a reduction in the dispersive component. The rolling bottle test revealed that bitumen blends containing IL and FRL displayed superior stripping resistance compared to the base bitumen, retaining more coating after testing. This enhancement in performance was attributed to the increased heteroatom content [sum of nitrogen (N), oxygen (O), and sulfur (S)] and higher IS═O and IC═O indices upon adding the lignin materials. While the energy ratio obtained from the SFE alone did not entirely explain the stripping resistance of lignin-substituted bitumen, the presence of heteroatoms like N, O, and S, and the presence of silicon (Si) and associated functional groups played a substantial role in the chemical adhesion of these bitumen blends to aggregates. In conclusion, the incorporation of IL and FRL lignin materials holds promise for enhancing the stripping resistance of base bitumen. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the adhesion of municipal solid waste incinerator bottom ash (MSWIBA) and limestone to asphalt using the principles of surface energy theory. MSWIBA asphalt mixes are known for their satisfactory water stability, with adhesion being a crucial factor, as demonstrated in previous freeze-thaw splitting tests. Contact angles of ground MSWIBA and limestone were measured using a capillary rise test, eliminating the influence of material surface structure. Subsequently, adhesion work and spalling work were calculated to correlate with water-induced damage. The results showed that the sequence of adhesion work was fine MSWIBA > limestone > coarse MSWIBA, while the sequence of spalling work was coarse MSWIBA > limestone > fine MSWIBA. The adhesion of MSWIBA asphalt mixes was evaluated using the water boiling test image method to validate the findings of surface energy theory. In both asphalt tests, the spalling rate followed this sequence: coarse MSWIBA > limestone > fine MSWIBA. The Adhesion index ER ranked as follows: ER Fine MSWIBA > ER limestone > ER coarse MSWIBA. These results suggest that the water stability of MSWIBA asphalt mixes is influenced by the surface energy of the components. Consequently, indices derived from surface energy theory can be applied in formulating and predicting the properties of MSWIBA asphalt mixes. [ABSTRACT FROM AUTHOR]

Purpose: The surface characteristics of thermally and chemically modified wood, such as surface roughness, surface free energy (SFE) and wettability, are important properties that influence further manufacturing processes such as gluing and coating. The aim of this paper was to determine the influence of the surface roughness of thermally and chemically modified teak wood on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated to give a valuable information for their further application. Design/methodology/approach: The woods tested in this study were fast-growing teak woods that were prepared in untreated and treated with furfuryl alcohol (FA), glycerol maleic anhydride (GMA) and thermal. SFE values were calculated using the Rabel method. The wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the Shi and Gardner model model was used to evaluate the wettability of the varnishes on the wood surface. The bonding quality of the varnishes was measured using a cross-cut test based on ASTM 3359-17 standard. In addition, durability against subterranean termites in the field of these modified teak woods was also investigated according to ASTM D 1758-06. Findings: The results showed that furfurylated and GMA-thermal 220°C improved the durability of teak wood against termites. The furfurylated teak wood had the roughest surface with an arithmetic average roughness (Ra) value of 15.65 µm before aging and 27.11 µm after aging. The GMA-thermal 220°C treated teak wood was the smoothest surface with Ra value of 6.44 µm before aging and 13.75 µm after aging. Untreated teak wood had the highest SFE value of 46.90 and 57.37 mJ/m2 before and after aging, respectively. The K values of untreated and treated teak wood increased owing to the aging treatment. The K values for the water-based acrylic varnish were lower than that of the solvent-based alkyd varnish. The untreated teak wood with the highest SFE produced the highest bonding quality (grades 4–5) for both acrylic and alkyd varnishes. The solvent-based alkyd varnish was more wettable and generated better bonding quality than the water-based acrylic varnish. Originality/value: The originality of this research work is that it provides evaluation values of the durability and SFE. The SFE value can be used to quantitatively determine the wettability of paint liquids on the surface of wood and its varnish bonding quality. [ABSTRACT FROM AUTHOR]

The aim of this research is to reduce the number of defects caused by the hydrophobicity of silica aerogel (SA) in the interfacial transition zone formed by this solid aggregate and a liquid binder in an alternative construction composite (paste). A new technique for controlling compatibility issues has been developed by modifying the chemicals and physical properties involved, evaluating two surfactants that function as elements that increase adhesion strength. The characteristics of wettability and free surface energy are beneficial for macroscopic morphology, microscopic structure, porosity, pore size, and physisorption, and they influence the mechanical and thermal properties of the composites. The contact angle shows that the composites obtained with the smallest SA particle size modify the wettability of the composite, increasing the contact angle to 136°, thus approaching the limit of superhydrophobic surfaces. Conversely, the composites with the large SA particles sizes decrease the angle to 94°, approaching the hydrophilic limit. The copolymer (COP) is the most efficient surfactant, achieving high surface energies, sometimes doubling those of composites integrated with only SA. Microscopy images show the presence of additional compact and homogeneous composites, with few separations and cracks. Additionally, the porosity increases to a total pore volume of 0.3376 cm3/g, and the specimen has an average pore size of 26.576 nm and a surface area of 50.811 m2/g. The compounds modified with the copolymer A3100COP and A3110COP and those modified with A3100S and silane (S) achieve great efficiency, with a mechanical strength of 5.19 MPa and a thermal conductivity of 0.141 W/(m·K) after 28 days. [ABSTRACT FROM AUTHOR]

In current research, Makrofol HS polymeric films have been utilized to evaluate the alterations in the surface properties under an atmospheric-pressure dielectric barrier discharge (DBD) plasma source. Upon DBD plasma exposure with various exposure durations ranging from 10 min to 120 min, the structural, surface wettability, surface free energy, surface roughness, and hardness features of Makrofol HS films have been studied and analyzed using different techniques. The FTIR spectra demonstrated that small changes in the band intensities correspond to the C-O-C as well as C=O bonds. Further, the changes in the absorption bands are correlated to the treatment time, leading to two critical processes, degradation, and crosslinking. The results of surface wettability displayed that the liquids' contact angle decreased from 84 ± 3o, 77 ± 3o and 62 ± 2o for water, glycerol, and dimethyl to 45 ± 1o, 42 ± 1o, and 36 ± 1o for untreated and treated samples at the highest treatment time, respectively. Also, the surface free energy significantly amended with increasing plasma exposure time. This modification in the treated surface indicates the increase in the polar groups on the treated surfaces, which then become hydrophilic surfaces. The samples' surface roughness parameters Ra, Rq, and Rz increased from 0.057 ± 0.003, 0.084 ± 0.004 and 0.366 ± 0.02 mm for untreated samples to 1.463 ± 0.073, 1.707 ± 0.085, and 6.839 ± 0.34 mm for treated samples at the highest treatment time, respectively. The Vickers hardness measurements showed an increase in the Vickers hardness from 12.31 ± 0.61 kgf/mm2 for the untreated sample to 44.89 ± 2.24 kgf/mm2 for the treated sample at the highest duration. [ABSTRACT FROM AUTHOR]

In order to ensure accurate spraying of pesticides and reduce the loss of pesticides in fruit trees, a calculation model of precise pesticide spraying quantity in orchards was established. The model included the canopy parameters, interface properties of the fruit tree, and the pesticide destination in the orchard, which could be used to guide the modes of spraying for different plant protection machinery under different planting patterns in the orchard. By selecting 'Fushi' apple leaves of different phenological periods as research objects, the leaf surface free energy and canopy parameters were tested. The relationship between liquid surface tension and maximum liquid holdup was established for apple leaves. The maximum pesticide loading of the whole tree was calculated based on maximum liquid holdup and canopy parameters. The calculation model of precise pesticide spraying quantity was established, combined with the pesticide destination in the orchard. The application of two kinds of spraying machines, stretcher plunger pump sprayer in the low-density planting orchard and selfpropelled axial flow sprayer in the close planting orchard, were taken as examples, and the practicability of the model was verified. The results showed that the use of a stretcher plunger pump sprayer in the early stage in the low-density planting orchard could save 37.40% of liquid compared with the original, and 18.75% of liquid could be saved in the later stage. The use of a self-propelled axial flow sprayer in the late stage of the close planting orchard can save 28% of the liquid. There was no significant difference between the control efficacy and the dosage of conventional liquid medicine. This model combined the interface properties of apple leaves with the application equipment could not only calculate accurately the spraying amount of pesticide according to the actual situation of the orchard， but also evaluate the applicability of pesticide liquid at a certain period. The mode could adjust the parameters of the pesticide liquid and spray machine according to the actual situation, so as to achieve the purpose of precise pesticide application. [ABSTRACT FROM AUTHOR]

Components of surface free energy (SFE) are critical to reveal the interactions between liquids and solids, and many interface phenomena can be interpreted by using these components. However, calculation of SFE components precisely with semiempirical approximations requires special expertise in surface science field. In this study, various machine learning algorithms (SVM, GPR) were utilized to construct models for the prediction of SFE from published data sets including contact angle values of water, formamide and diiodomethane. While creating the model data set, care was taken to choose different solid surface types. To objectively assess the validity of the constructed models, the tenfold cross-validation method was used for Case 1 and Case 2, respectively. For performance evaluations, R2, adjusted R2, RMSE and N-RMSE values of each model were calculated. The SVM and GPR models performed extremely well in the calculation of SFE components based on acid–base approach with regression coefficient values of about 0.99. In addition, estimation of the SFE components from experimental data that were not used in model training was made with the created MATLAB GUI interface. The γ S LW and γ S Tot parameters were predicted more accurately than the γ S + , γ S - and γ S AB components. The Case 1 model was more successful, especially in surface energy calculations of polymer-based surfaces. Finally, the proposed approach was evaluated by considering its advantages and disadvantages. [ABSTRACT FROM AUTHOR]

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There is limited information on the characteristics and performance of paving mixtures made with 100% bio-binders. Moisture damage resistance of this type of mixture is a concern since the components of the bio-binder may have a higher affinity with water than asphalt binders. In this context, this paper presents a moisture damage susceptibility evaluation of wood-based bio-binder-aggregate interfaces in terms of energy parameters calculated from surface free energy components. The bio-binder was used as a total replacement for asphalt binders, and the responses were compared to a neat- and a highly modified-asphalt binder, considering different aggregate sources. Results suggest the bio-binder has similar moisture damage resistance to the neat asphalt binder and higher resistance than the highly modified asphalt binder, providing a first indication for the potential use of this bio-binder as 100% asphalt binder replacement. However, additional research is still required to validate these findings at the mixture level. [ABSTRACT FROM AUTHOR]

Radiofrequency (RF) low-pressure plasma has been applied to improve natural leather's wettability and water absorption. The plasma was generated using RF discharge of the Ar-He gas mixture at 60 and 120 W power using different treatment times (30, 60, 120, 180, and 300s). Before and after treatment, the contact angle, surface free energy, and water absorption ratio were measured. It was observed that a 300s plasma treatment time and plasma power 60 and 120 W is enough to decrease the water contact angle from 83.56 for an untreated sample to 0°. The surface-free energy and the water absorption ratio increase with an increase in the treatment time and plasma power. The findings demonstrate that plasma treatment increases the wettability of the surface of leather samples. In addition, the change in leather properties was analyzed by scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry, Fourier transform infrared spectroscopy.

The interfacial bonding capacity between cement emulsified asphalt composite binder (CEACB) and reclaimed asphalt pavement (RAP) plays a critical role in improving the pavement performance of cold recycled asphalt emulsion mixtures (CRAEMs). This study aims to investigate the formation and development of the interfacial bonding capacity between CEACB and RAP. First, the dynamic wettability and the spreading behaviors of CEACB on RAP surfaces were explored according to the surface free energy theory. Second, digital image processing (DIP) technology was employed to recognize interfacial failure patterns. Lastly, the influence of internal and external factors on the interfacial bonding capacity between CEACB and RAP during the curing process was analyzed via grey relational analysis (GRA). The results indicate that a moderate cement content with a mass ratio of asphalt to cement equivalent to 1.0 can significantly enhance the wettability of CEACB on RAP surfaces. By appropriately prolonging the curing time and controlling the curing temperature, it is possible to increase the bonding strength between CEACB and RAP. Additionally, a strong correlation exists between initial wettability and ultimate bonding capacity during the bonding strength curing process. The good wettability that developed in the initial stage of interfacial strength formation relates to the decreased spalling rate of CEACB on the RAP surface. This study is not only devoted to understanding the mechanisms that can enhance CRAEM performance but also provides important guidance for practical engineering applications of cold recycled asphalt pavements. [ABSTRACT FROM AUTHOR]

This study investigated the efficacy of three spray adjuvants (Coerce, Wetcit, and Silwet408) in enhancing dinotefuran permeation in rice leaves. Different concentrations of these adjuvants were tested using an external standard method. The rice leaf surface was analyzed by using the van Oss–Chaudhury–Good method to establish a link between surface free energy (SFE) and dinotefuran permeation. All of the adjuvants effectively increased dinotefuran permeation in rice leaves, with the highest permeation of 8.496 mg/kg achieved using Wetcit at 1000 mg/L. The SFE of the rice leaf surface was determined to be 29.28 mJ/m2. A notable correlation was observed between the energy difference (the SFE of the pesticide liquid versus the SFE of the rice leaf surface) and permeation. Various fitting methods, including linear, exponential, logarithmic, polynomial, and power methods, were applied. Polynomial fitting demonstrated the highest coefficient of determination (R2 > 0.9000). The relationship between the permeation (y) and energy difference (Δγ) conformed to the polynomial equation y = aΔγ2 + bΔγ + c, where a, b, and c are constants. This model provides a predictive tool for the optimal dosage of spray adjuvants according to target plant characteristics, enhancing the understanding of the interaction between pests and pesticides. [ABSTRACT FROM AUTHOR]

The continuous growth of industrial solid waste production has generated many environmental problems. We evaluated the potential of industrial solid waste as a substitute filler in asphalt mastic, with the aim of increasing the use of sustainable road construction materials. In this study, X-ray fluorescence spectroscopy (XRF) and scanning electron microscopy (SEM) were used to characterize the oxide composition and micromorphology of limestone (LS), red mud (RM), steel slag (SS), and ground granulated blast-furnace slag (GGBFS). Four asphalt mastics containing LS, RM, SS, and GGBFS with a filler-to-binder weight ratio of one were prepared. An evaluation of the rheology and wetting of the solid-waste-filler asphalt mastic was conducted using a frequency sweep, temperature sweep, linear amplitude sweep (LAS), multiple stress creep and recovery (MSCR), and surface free energy (SFE) methods. The results showed that SS increased the complex modulus, elastic component of the asphalt mastic and decreased the nonrecoverable creep compliance at stress levels of 0.1 and 3.2 kPa, which improved the rutting resistance of the asphalt mastic and reduced deformation under high-temperature conditions. The RM and GGBFS increased the fatigue performance of the asphalt mastic under strain loading, enhanced its fatigue life, and maintained good performance under long-term loading. The dispersive component of the SFE parameter of the solid-waste-filler asphalt mastic was larger than the polar component for the largest share of the surface energy composition. The SFE of the asphalt mastic prepared from the industrial solid-waste filler was reduced; however, the difference was insignificant compared to the limestone asphalt mastic. Solid-waste-filler asphalt mastic has performance characteristics, and its actual application can be based on different performance characteristics to select an appropriate solid-waste filler. The results of this study provide new technological solutions for solving the utilization rate of solid waste materials and sustainable road construction in the future. [ABSTRACT FROM AUTHOR]

The article presents the exploration of flax and hemp fibers' surface free energy depending on the chemical composition of the fiber, which is closely related to the plant variety and the method of extracting the fiber. For this purpose, tests of the surface free energy (SFE), evaluation of the percentage content of individual fiber components and FTIR analyses were conducted. The research was carried out with the use of fibrous materials prepared in three different ways: 1. To analyze the effect of subsequent stages of flax fibers refining process on chemical composition and SFE, 2. to explore the dependence of fiber SFE on hemp variety, the water-retting hemp fibers were used, 3. To evaluate the influence of the retting method of hemp fibers BIAŁOBRZESKIE variety on SFE, the fibers extracted with the use of dew and water retting were used as the research material. The study confirmed that the content of individual components in the fiber influenced its sorption capacity and therefore determined its hydrophilic properties. The values of Pearson's linear correlation coefficients determined in the statistical analysis proved that the surface free energy was strongly correlated with the content of individual components in the fibers. Understanding the wettability characteristics of bast fibers will allow modeling the properties of products made of these fibers and designing surface modification processes in order to obtain specific functionality of textile products, depending on their intended utilization. [ABSTRACT FROM AUTHOR]

Aging due to environmental conditions significantly affects the occurrence of fatigue cracking in hot-mix asphalt (HMA). Previous analyses showed that aging reduces mastic resistance and bitumen-aggregate adhesion, but these experiments were usually performed on HMA samples, and failure mechanisms were not reflected in the results. Accordingly, via the surface free energy (SFE) theory, this study examined the impact of aging on the fatigue cracking mechanism of HMA. Dynamic methods, including indirect tensile fatigue test (ITFT) and Pull-Off tensile strength (POTS), were applied to HMA samples at 5 and 20 ˚C to study the association between the results of SFE tests. Two performance-graded bitumens (PG 58–22 and PG 64–16), two aggregates with different mineralogical properties (limestone and siliceous), and a polymeric additive (ultra-high-molecular-weight polyethylene-UHMWPE) as a bitumen modifier were also used. Based on the results, aging decreased and increased the polar (28.6%) and non-polar (15.14%) properties of bitumens, respectively. A decline in polar properties lowered the bitumen-aggregate adhesion (8.11%), which was generally because of polar bonds. The rise in cohesion free energy (CFE) by up to 9.5% and non-polar properties due to aging decreased the failure probability in the bitumen film of the aged specimens. UHMWPE improved the non-polar properties of the asphalt (by up to 15.09%), providing greater resistance against aging and reduced adhesion with mineral aggregates. According to the POTS test results at the state of cohesive failure, aging enhanced the POTS of cohesion, especially in UHMWPE-modified bitumen-aggregate by up to 12.12%. POTS in the state of cohesive failure was independent of adhesion free energy (AFE), yet CFE influenced POTS at the state of adhesive failure. Based on the fatigue life of HMA, even though aging increased the CFE and stiffness of HMA, the decline in the AFE parameters and flexibility reduced the fatigue life of the aged HMA in comparison to similar non-aged specimens (by up to 5.17%). The polymer additive significantly improved the resistance of asphalt mixtures to cohesion (by up to 23.16%), adhesion (by up to 16.78%), and fatigue life (by up to 12.8%). Additionally, in aged samples, there was a noticeable reduction in the parameters of cohesion, adhesion, and fatigue life in the modified samples compared to the base samples.

False heartwood is a common defect in beech wood. If the false heartwood is healthy and without microbial attacks, it is possible to utilize such material. Application of adhesives and coatings is an important part of the wood furniture industry. Studying wood surface properties provides answers to problems in application of glues, coating materials, and similar. Comparing wettability and surface free energy of false heartwood, ripe wood, and sapwood zones of beech was the focus of this paper. Two-way ANOVA with Duncan post-hoc test of multiple comparison was used for testing of the hypotheses and statistical evaluation of the results. The zones were also examined with light microscopy. Two testing liquids were used in wettability experiment – redistilled water and diiodomethane. Ripe wood showed the best wettability for both testing liquids among the wood zones. Significant differences in contact angles at the beginning of the wetting process, equilibrium contact angles, and surface free energies were found in almost all pairwise comparisons of the wood zone and testing liquid factors. The pairs where significant difference was not found were as follows: false heartwood and ripe wood in testing with redistilled water, and ripe wood and sapwood in testing with diiodomethane. Equilibrium times in all wood zones for both testing liquids were also statistically evaluated. Significant differences were found in all wood zones in testing with redistilled water. In testing with diiodomethane, equilibrium time for false heartwood was significantly different from ripe and sapwood zone equilibrium times.

The subject of the research presented in this paper was the evaluation of the technology of surface preparation of steel samples in terms of anti-adhesion and mechanical properties through the use of PFA coatings. Such coatings are used in many industries, e.g. in the manufacture and operation of metal moulds used, for example, in the production of resinous components. The specimens used in the study, which represented the surface of the moulds, were made from DC01 sheet. Six variants of release coating technology were used, differing in the number of technological operations and parameters. In the final stage, appropriate test methods were used to assess the energy properties of the coatings produced, the mechanical properties in terms of deformation of the supporting structure and the mechanical properties in terms of the effects on the coating itself. The scope of the research made it possible to determine the main properties that the manufactured coatings have in terms of their future practical applications. The results obtained for the surface free energy determined from the measurement of the surface wetting angle, the mechanical properties obtained from the three-point bending test and the evaluation of the surface quality of the coatings subjected to compressive and tensile deformations in the bending test, as well as the functional properties of the coatings in terms of their durability and adhesion determined in scratch tests, showed that the best characteristics were obtained for variant 6. This variant consisted of sequentially, after the initial stage, applying a primer layer and drying it for 15 minutes at 250°C, applying a PFA layer to the component at 150°C and then drying it for 15 minutes at 200°C and curing it for 20 minutes at 380°C. An additional layer of PFA was then applied and dried for 15 minutes at 200°C and cured for 20 minutes at 340°C. In addition, a long annealing for 3 hours at 340°C was applied in a given variant.

Titanium and titanium alloys are the prevailing dental implant materials owing to their favorable mechanical properties and biocompatibility, but how roughness dictates the biological response is still a matter of debate. In this study, laser texturing was used to generate eight paradigmatic roughened surfaces, with the aim of studying the early biological response elicited on MC3T3-E1 pre-osteoblasts. Prior to cell tests, the samples underwent SEM analysis, optical profilometry, protein adsorption assay, and optical contact angle measurement with water and diiodomethane to determine surface free energy. While all the specimens proved to be biocompatible, supporting similar cell viability at 1, 2, and 3 days, surface roughness could impact significantly on cell adhesion. Factorial analysis and linear regression showed, in a robust and unprecedented way, that an isotropic distribution of deep and closely spaced valleys provides the best condition for cell adhesion, to which both protein adsorption and surface free energy were highly correlated. Overall, here the authors provide, for the first time, a thorough investigation of the relationship between roughness parameters and osteoblast adhesion that may be applied to design and produce new tailored interfaces for implant materials.

The aim of this work was to examine the influence of polycaprolactone (PCL) as a soft segment (SS) on the surface properties of polyurethane networks (PUNs). Five PUNs with different SS content (from 10 to 50 wt%) were prepared using Boltorn® aliphatic hyperbranched polyester of the second pseudo generation and isophorone diisocyanate as components of hard segments. The structure, hydrophobicity, wettability, and swelling behavior of these PUNs were investigated. Primarily, the obtained results showed that properties of prepared PUNs strongly depend on the content of SS that is, PCL. It has been established that the increase of SS content reduced the degree of hydrogen bonding in PUNs. Also, the increase of the SS content in PUNs induced appearance of more pronounced microphase separated morphology, better hydrophobicity and non‐wetting with diiodomethane. Simultaneously, the increase of the SS content led to the decrease of contact angles with formamide, and surface free energy of the prepared PUNs. These PUNs show good surface properties that are required for their potential application such as coatings. [ABSTRACT FROM AUTHOR]

The new developed technique, CO 2 -alkaline-water two-phase displacing gas and wetting coal (CADW), can obviously improve coal seam water injection effects. In this work, the microscopic seepage mechanism of CO 2 -alkaline-water in coalbed and its influence on coal wettability were investigated in detail. The results indicated that, the CADW measure could clearly increase coal wettability. After the CADW, the specific surface area of LS and ZX coals increased by 33.44%, 14.61% and the total pore volume increased by 121.60%, 19.48% respectively. Besides, the contact angle of two coals decreased by 25.30% and 6.62% severally. Further investigation showed that, the polar force increased evidently after using the CADW. As a result, the surface free energy of LS and ZX coals calculated by the Owens-Wendt method increased by 13.82% and 6.03%, that acquired by the Van Oss model increased by 10.26% and 6.32%, respectively. In addition, the CADW could obviously increase contents of hydrophilic groups in coal. The content of -OH in two coals increased by 20.09% and 32.10%, the C O density increased by 27.27% and 70.77% respectively. The results can provide valuable reference for preventing gas outburst risk and reducing mine dust concentration. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into the enhanced performance of photoelectrochemical (PEC) cells through the decoration of CdSe and Al-doped CdSe nanoparticles on ZnO rods. The capacitance-voltage study reveals that Al doping increases the donor concentration and improves minority carrier diffusion time while reducing dispersion at grain boundaries. Spectral response analysis demonstrates that CdSe/ZnO/FTO and Al: CdSe/ZnO/FTO photoanodes exhibit maximum short-circuit currents at a wavelength of 675 nm, corresponding to a bandgap of 1.84 eV. Al doping shifts the spectral response to longer wavelengths, indicating an estimated bandgap of 1.72 eV. Furthermore, the effect of surface free energy and polarity on the developed photoanode materials is investigated. CdSe and Al-doped CdSe nano particles on ZnO/FTO surfaces exhibit reduced water contact angles, indicating improved wettability. The surface free energy decreases with Al doping, potentially influencing electrolyte absorption and the interaction between photoanodes and electrolytes. The presence of polar hydroxyl (-OH) groups and Al+++ ions on the Al: CdSe nano particles contributes to their impact on surface free energy. These findings provide valuable insights for optimizing PEC cell performance by manipulating doping concentrations and surface characteristics. [Display omitted] • Aluminum doping enhances CdSe/ZnO/FTO photoanode performance. • Sensitization broadens absorption range and improves solar radiation capture. • Investigating surface free energy's impact on PEC performance. • Exploring the connection between surface properties and PEC efficiency. • Advancing solar energy conversion through surface engineering. [ABSTRACT FROM AUTHOR]

Moisture damage is a prevalent failure in asphalt pavements, which is directly linked to stripping and bitumen-aggregate adhesion. Also, it can lead to other main damages. This research aims to evaluate the adhesion and moisture susceptibility of asphalt mixes containing a new polymer additive namely ultra-high-molecular-weight polyethylene (UHMWPE) with 2 and 4% bituminous weight was performed. Moreover, the tensile strength ratio (TSR), boiling water test by the image processing of coating ratio ((CR) index), and surface free energy (SFE) were conducted and compared. The results indicated that adding 4% UHMWPE to the base bitumen (B-B) increased the 27% TSR index and 31% CR index compared to the base mixtures (without additive). The best performance in the mixture of limestone (LS) and bitumen was associated with 4% UHMWPE (LS-B-UHMWPE4), in which both TSR and CR indices had the highest values. The results of SFE components indicated that the free cohesion energy in modified bitumens has increased substantially by 65% compared to B-B. Additionally, the free adhesion energy in modified bitumens with limestone and granite has demonstrated higher values. The highest increase in TSR, CR, and SFE indices was observed in the modified mixture with LS-B-UHMWPE 4. [ABSTRACT FROM AUTHOR]

Radiofrequency (RF) low-pressure plasma has been applied to improve natural leather’s wettability and water absorption. The plasma was generated using RF discharge of the Ar-He gas mixture at 60 and 120 W power using different treatment times (30, 60, 120, 180, and 300s). Before and after treatment, the contact angle, surface free energy, and water absorption ratio were measured. It was observed that a 300s plasma treatment time and plasma power 60 and 120 W is enough to decrease the water contact angle from 83.56 for an untreated sample to 0°. The surface-free energy and the water absorption ratio increase with an increase in the treatment time and plasma power. The findings demonstrate that plasma treatment increases the wettability of the surface of leather samples. In addition, the change in leather properties was analyzed by scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry, Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of surface pretreatment on the shear bond strength of resin luting cement to saliva-contaminated resin core foundation. The surface free energy (γS) of the adherent surfaces was examined. The two-way analysis of variance revealed that the surface pretreatment and storage conditions had a significant effect on the strength of the bond to resin core foundation. The γS values of the saliva-contaminated group were significantly lower than those of the other groups, and they tended to improve after surface pretreatment. The tendency of improvement in γS values differed depending on the type of pretreatment agents. Surface treatment with solutions containing functional monomers is effective in removing saliva contaminants from the resin core foundation surfaces and in creating an effective bonding surface for the resin luting cement [ABSTRACT FROM AUTHOR]

In order to study the adhesion properties of fast-melting SBS-modified asphalt (SBS-T) at the interface with aggregates, the contact angles of three dosages of SBS-T asphalt with three liquids (distilled water, glycerol, and formamide) were determined by the sessile drop method based on surface free energy theory. The evaluation indexes such as cohesion, asphalt–aggregate adhesion, stripping work and energy ratio of the asphalt were analyzed and the adhesion properties of the asphalt–aggregate system were investigated with the help of micromechanical methods. The results indicate that SBS-T can improve the adhesion properties of the asphalt. Furthermore, as the dosage of the modifier increases, the cohesion work, adhesion work, and energy ratio of the SBS-T asphalt exhibit a similar rise. As the spalling work reduces and the adhesion between asphalt and aggregate improves, it is noteworthy that the SBS-T asphalt–aggregate system exhibits superior adhesion performance compared to the SBS-modified asphalt–aggregate system, despite the same dosage. [ABSTRACT FROM AUTHOR]

This paper investigates if the polar groups induced by a plasma treatment can increase the lap shear strength of laser-joined metal and plastic hybrids. Optimal laser joining parameters for cold-rolled AISI304–polyamide 6.6 and sandblasted AISI304–polypropylene hybrids were developed at 2.85 MPa and 4.22 MPa, respectively. The surface free energy was doubled for all used plasma gases to a value of ca. 80 mN m−1 at 180 s. The plasma-treated samples were joined and tested. The arithmetic means of the plasma-treated hybrids' lap shear strength with polyamide 6.6 varied slightly, but all measured values were within the range of the untreated samples. Residue on the sheared metal samples indicated covalent bonds between AISI304 and polyamide 6.6. The lap shear strengths of the plasma-treated polypropylene hybrids were significantly reduced between −30.8% and −53.3%, depending on the used plasma gas. This was attributed to the over-aging and development of low-molecular-weight oxidized materials, which led to a weak boundary layer. No residue of polypropylene was found on treated or untreated lap shear samples. No correlation between the surface free energy and lap shear strength could be found. [ABSTRACT FROM AUTHOR]

AbstractThe wettability of chemical pesticides on the surfaces of crop leaves is crucial for enhancing the efficiency of chemical solutions. This work examined the wetting behavior of 28-Epimotabrassinolide (28-HB) combined with various surfactants on the adaxial and abaxial leaves at the jointing and boot stages of wheat. The microstructure of the leaf surface was characterized by ultra-depth microscopy, and the surface free energy (SFE) of the leaf was calculated by the Owens–Wendt–Rabel–Kaelble (OWRK) method. The surface tension of the 28-HB solution with different surfactants added and the contact angle on the leaf surface at the jointing and boot stages were measured. Compared with the boot stage, the wettability of the adaxial and abaxial wheat leaves was superior to that of the jointing stage. The addition of surfactants to the 28-HB improved the spreading behavior of droplets on the surface of leaves. Specifically, when fatty lcohol polyoxyethylene ether (AEO9) was added to 28-HB, the wettability of the droplets on the jointing wheat leaf surface was greatly enhanced. Additionally, cetyltrimethylammonium bromide (CTAB) and sodium lauryl sulfate (SDS) improve the wettability of 28-HB on wheat leaves at the boot stage. When the surface tension of the solution is lower than the free energy of the solid surface, the dispersion component in the free energy of the leaf surface aligns with the dispersion component in the surface tension of the solution, facilitating maximum wettability of the solution on the leaf surface. This work offers a fresh perspective on enhancing the efficiency of surfactants in achieving superhydrophobic leaf wetting. [ABSTRACT FROM AUTHOR]

A fast-melting styrene-butadiene-styrene-based modifier (SBS-T) was applied for rapid modification for asphalt mixtures. No relevant studies are available to support the effect of this new fast-melting modifier on asphalt-aggregate adhesion properties, and this paper is to remedy the assessment of the adhesive properties of the modified SBS modifier in asphalt mixtures. At the micro-scale, the sessile drop method is utilized to measure the contact angle of bitumen and aggregate and to compute thermodynamic parameters based on surface energy theory. Meanwhile, the effects of short-term and ultraviolet (UV) aging on the thermodynamic parameters of SBS-T modified asphalt (SBS-T-MA) were investigated. The asphalt-aggregate adhesion properties were further verified on a macro-scale scale by pull-off tests. The outcomes suggested that the higher the dosage of SBS-T modifier, the better the thermomechanical characteristics of the bitumen binder. The adhesive properties of SBS-T-MA and aggregates were promoted in short-term aging and decreased in UV aging. Statistical analysis of the pull-off test indicated a significant correlation between pull-off strength and energy ratio. It was demonstrated that adhesion damage occurred between asphalt and aggregate in the pull-off test and that the greater the energy ratio between asphalt and aggregate, the greater the asphalt-aggregate pull-off strength. [ABSTRACT FROM AUTHOR]

Coal reservoirs have a complex pore structure, which is accompanied by energy changes during the adsorption of methane gas. To study the heterogeneity of energy changes during the pore and methane adsorption processes in coal reservoirs, fractal dimension analysis was employed to analyze the heterogeneity of coal pores. The heterogeneity of energy changes during the isothermal adsorption process was analyzed using adsorption potential and surface free energy theory. The results show that sample PY-1, PB-1, and PB-2 mainly develop micropores, while sample PY-2 mainly develops macropores, and the pore distribution of different samples is significantly different. Micropores are the main sites for methane adsorption, but not the determining factor affecting methane adsorption. Coal􀆳s pore structure and inherent properties exert a significant influence on the heterogeneity of methane adsorption. As the vitrinite content increases, the complexity of pore structure and the fractal dimension of pores also increase, leading to enhanced heterogeneity. Consequently, methane adsorption exhibits higher uptake, accompanied by more pronounced variations in adsorption potential and surface free energy. [ABSTRACT FROM AUTHOR]

Fluorine-containing liquid crystal polymers have excellent hydrophobic stability, making them attractive for use in the field of stable hydrophobic coatings. To improve the hydrophobic stability of fluoropolymers, a novel fluoro acrylate monomer (FAM) containing a rigid cyclohexane structure was simply synthesized using isophorone diisocyanate (IPDI), hydroxyethyl methacrylate (HEMA), and perfluorohexylethanol (S104) as raw materials and its homopolymer (PFAM) was prepared by radical solution polymerization. The structure, liquid crystal behavior, thermal properties, hydrophobic properties, and surface properties of FAM or PFAM and a reference substance, dodecafluoroheptyl methacrylate (DFMA) and its homopolymer (PDFMA), were studied using various techniques including FT-IR, NMR, GPC, XRD, POM, DSC, TGA, XPS, AFM, and static/dynamic contact angle measurements. The results indicate that FAM and PFAM are thermally liquid crystalline. PFAM's thermal stability is higher than that of PDFMA. The presence of a rigid cyclohexane structure facilitates the dense distribution of fluorocarbon chain tails of the homopolymer and also prevents surface reconstruction when the homopolymer comes into contact with polar liquids, resulting in improved hydrophobicity and hydrophobic stability. Thus, this study provides a straightforward method for the synthesis of fluoro acrylates with surface stability, highlighting their potential application in hydrophobic coatings. [ABSTRACT FROM AUTHOR]

Fluorine-containing liquid crystal polymers have excellent hydrophobic stability, so they have attracted much attention in the field of stable hydrophobic coatings. Thus, a novel fluoroacrylate (FAM) containing rigid cyclohexane structure was simply synthesized to improve the hydrophobic stability of fluoropolymers using isophorone diisocyanate (IPDI), hydroxyethyl methacrylate (HEMA) and perfluorohexylethanol (S104) as raw materials. The structure, liquid crystal behavior, thermal properties, and hydrophobic properties of monomers and homopolymers were studied by Fourier transform infrared spectrometer, nuclear magnetic resonance spectrometer, X-ray diffractometer, polarizing microscope, differential scanning calorimeter, thermogravimetric analyzer, and static/dynamic water contact angle measuring instrument and dodecafluoroheptyl methacrylate (DFMA) used as a reference substance. The results showed that the synthesized product was a fluoroacrylate containing a rigid cyclohexane structure. The monomer and homopolymer are thermotropic liquid crystals, which facilitate the dense distribution of fluorocarbon chains at the end of the homopolymer side groups and prevent surface group reconfiguration when the homopolymer comes into contact with polar liquids, resulting in better thermal stability, hydrophobicity and hydrophobic stability. [ABSTRACT FROM AUTHOR]

The effects of short-term aging (STA) and long-term aging (LTA) on moisture damage mechanisms were investigated using mechanical and thermodynamic methods. PG58-22 and PG64-16 asphalt binders modified with Dodecylamine (DA) and Wetfix (WT) additives and limestone and granite aggregates were used. The moisture sensitivity was assessed using the indirect tensile strength (ITS) test via the modified Lottman test and the surface free energy (SFE) method. As asphalt binder becomes harder due to aging, ITS values increase in dry conditions. However, ITS values decrease due to the texture and mineralogical properties of aggregates, the reduction of mastic cohesion and asphalt binder-aggregate adhesion because of water infiltration and weakening of the mixture in wet conditions. The tensile strength ratio (TSR) test revealed that TSR values decrease due to aging. The cohesion free energy of the PG64-16 asphalt binder increased by 8.9% in the STA state and by 29.8% in the LTA state compared to the unaged state. This rise in PG58-22 was about the same as that in PG64-16. Asphalt binder aging in all the samples reduced the adhesion energy. These variations indicated that aging reduces the probability of cohesion failure and increases the probability of adhesion failure. [ABSTRACT FROM AUTHOR]

With the purpose of further reducing surface free energy to achieve better anti-bacterial adhesion effect of fluorinated dimethacrylate (FDMA)/tricyclo (5.2.1.0) decanedimethanol diacrylate (SR833s) based dental resin composites (DS), 1H,1H-heptafluorobutyl methacrylate (FBMA) was used to partially replace SR933s as reactive diluent. According to the degree of substitution, the obtained resin composites were marked as DSF-1 (20 wt.% of SR833s was replaced by FBMA), DSF-2 (40 wt.% of SR833s was replaced by FBMA), and DSF-3 (60 wt.% of SR833s was replaced by FBMA). Bisphenol A glycidyl dimethacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) based resin composite (BT) was used as control. The influence of FBMA concentration on double bond conversion (DC), contact angle, surface free energy, anti-bacterial adhesion effect against Streptococcus mutans (S. mutans), volumetric shrinkage (VS) and shrinkage stress (SS), flexural strength (FS) and modulus (FM), water sorption (WS) and solubility (SL) were investigated. The results showed that FBMA addition could reduce surface free energy from 44.6 mN/m for DS to 32.9 mN/m for DSF-3, and lead to better anti-bacterial adhesion effect (the amounts of adherent bacteria decreased from 2.03 × 105 CFU/mm2 for DS to 6.44 × 104 CFU/mm2 for DSF-3). The FBMA had no negative effects on DC, VS, SS, WS, and SL. Too high a concentration of FBMA reduced FS and FM before water immersion, but the values were still higher than those of BT. [ABSTRACT FROM AUTHOR]

BACKGROUND: The effective deposition of pesticide droplets on a target leaf surface is critical for decreasing pesticide application rates. The wettability between the target leaf surface and the pesticide spray liquid should be investigated in depth, with the aim of enhancing the adhesion of pesticide solutions. The wetting and deposition behavior of pesticides on target leaves depends on the properties of the liquid and the physical and chemical properties of the leaves. The physical and chemical properties of leaves vary with growth stage. This study aims to investigate the wetting behavior of banana leaf surfaces at different stages. RESULTS: The microstructures and chemical compositions of banana leaf surfaces at different stages were studied using modern methods. The surface structure of banana leaves exhibited a wide variety of characteristics at different growth stages, and the chemical composition changed marginally. The surface free energy (SFE) and polar and non‐polar components of banana leaves at different growth stages were measured by examining the contact angles (CA) of different test solutions on the surface of banana leaves. Previous research has suggested that changes in the CA and SFE correlate with changes in leaf surface wettability. In general, the new upper leaves of banana trees are composed of polar components and exhibit hydrophobicity. Non‐polar components become dominant as the leaf grows. The back surface of banana leaves was non‐polar at all growth stages, with a trend that was opposite to that of the front surface. The critical surface tension of the banana leaf surface at different growth stages ranged from 7.83 to 24.22 mN m−1, thus falling into the category of a low‐energy surface. CONCLUSION: The surface roughness and chemical characteristics of banana leaves affected the wettability of the leaf surface. Differences in the free energy and the polar and non‐polar components of the leaf surface at were seen at different growth stages. This study provides a favorable reference for the rational control of pesticide spraying parameters and the enhancement of wetting and adhesion of the solution on banana leaf surfaces. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Abstract Asphalt pavement is vulnerable to moisture damage when water infiltrates the asphalt-aggregate interface and weakens their bond. To prevent this problem, researchers have explored the use of additives to increase resistance against moisture damage. The moisture sensitivity of asphalt mixtures can be assessed by measuring their basic properties related to the mechanism of moisture damage. One effective approach to this is using the surface free energy method, which calculates bond energies between different materials’ surfaces and identifies the most appropriate combination of asphalt and aggregate. High cohesion or adhesion bonding is crucial for the proper performance of asphalt mixtures, such as moisture damage resistance. This study aimed to investigate the effect of carbon black additive on moisture damage resistance using surface free energy methods, comparing results with the Tensile Strength Ratio (TSR) test. Modified asphalts containing 4, 8, 12, and 16% carbon black were tested, with natural base asphalt as a control sample. The study used surface free energy theory to determine moisture sensitivity parameters of asphalt mixtures by obtaining surface free energy components of the raw materials and testing the ratio of tensile strength. Results showed that adding 8% carbon black to the asphalt mixture improved moisture sensitivity, and increasing additive content up to 16% reduced it but still provided better results than samples made with pure asphalt. The study concluded that the surface free energy method can determine the suitable combination of asphalt and aggregate materials for resistance against moisture damage.

This study aimed to evaluate the effect of airborne particle abrasion with different particles on the surface free energy, roughness, and biaxial flexural strength of a feldspathic ceramic by comparing it with hydrofluoric acid etching, the standard surface treatment, and polishing. Square-shaped feldspathic ceramic specimens (12 mm × 12 mm × 1.2 mm) were divided into subgroups as airborne particles abraded with alumina (AO3a, AO3b, AO25, AO50a, AO50b, AO90, AO110a, AO110b, AO120a, and AO120b), silica (SO50a, SO50b, SO100, and SO100/200), or nutshell granule (NS100/200), hydrofluoric acid etched, and polished (n = 12). Surface free energy (n = 5), roughness (n = 5), biaxial flexural strength (n = 12), and Weibull moduli (n = 12) were investigated. Data were evaluated with 1-way ANOVA and Tukey HSD tests, and possible correlations were investigated with Pearson’s correlation (α = 0.05). SO100/200 mostly had lower surface free energy (p ≤ 0.011), and polishing and etching led to higher surface free energy than AO3a, AO3b, and AO120a (p ≤ 0.031). Polished, SO100, and SO50b specimens mostly had lower roughness and AO125 had the highest roughness (p ≤ 0.029). SO100/200 mostly had lower biaxial flexural strength (p ≤ 0.041), and etched specimens had higher biaxial flexural strength than AO120a, AO120b, and SO50b (p ≤ 0.043). AO3b had the highest (33.56) and AO120b had the lowest (11.8) Weibull modulus. There was a weak positive correlation between the surface free energy and the biaxial flexural strength (r = 0.267, p = 0.011). A larger particle size mostly resulted in higher roughness, which was also affected by the particle shape. Most of the test groups had similar biaxial flexural strength to that of the hydrofluoric acid-etched group. Therefore, for tested feldspathic ceramic, airborne particle abrasion with tested parameters may be a suitable alternative without causing any further damage.

Interface phenomena that occur at the solid–liquid interface, such as wettability, adsorption, and particle aggregation, depend on the kind and magnitude of the solid surface free energy and electrokinetic properties found in water solutions. These phenomena are crucial for textile dyeing, finishing, and care. They characterize the material surface and change with different material pretreatment and finishing. In this paper, electrokinetic potential, isoelectric point, point of zero charge, a specific amount of surface charge and surface free energy of raw, enzymatically scoured, bleached, and finished cotton fabrics were investigated. Electrokinetic potential was measured by a streaming potential method and a specific quantity of surface charge by the back-titration method. For determination of the solid surface free energy components, the thin-layer wicking and contact-angle methods were used. On the basis of these results, components of solid surface free energy were calculated and discussed.

The modification of asphalt binder with natural rubber latex (NR) significantly improves the rutting and fatigue resistance of asphalt mixtures. However, NR-modified binder is prone to low workability and wettability due to its high viscosity. Therefore, this research focuses on examining the influences of silane and wax-based additives on the wettability of natural rubber-modified binders and the binder-aggregates adhesion performances. In this study, experimental and analytical approaches were used. The contact angles of asphalt binder were measured using a goniometer through the sessile drop method with three solvents: deionised water, formamide, and glycerol. The C++ algorithm was adopted to compute the surface free energy (SFE) elements of the asphalt binder. Analytical methods were employed to analyse the results based on the Young-Dupre equation, followed by linear regression to establish a correlation between the compatibility ratio (CR) and the SFE components. The results inferred that modified asphalt binders with additives possessed improved moisture resistance, wherein dry work adhesion values were less than 210 ​mJ/m2 under granite interfaces, whereas the limestone interface exhibited higher dry adhesion values of 340 ​mJ/m2 and below. Similar performance results were observed under wet adhesion conditions; with granite wet adhesive values observed below 120 ​mJ/m2, while limestone wet adhesion values were ascertained below 180 ​mJ/m2 for all tested samples and conditions. According to the spread–ability coefficient results, the limestone interface has greater spread-ability than granite interfaces. Meanwhile, compatibility ratio values indicated better compatibility of 1.9 or higher for tested samples under granite interfaces, whereas compatibility values of 1.7 and below were observed under limestone interfaces. Among the SFE components studied for correlation with CR, the acidic SFE component demonstrated excellent correlations (with R2 values greater than 0.91) under all ageing conditions. An inclusion of micro-level additive enhanced binder adhesion properties, resulting in a more resilient asphalt pavement.