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Stickiness is a phenomenon observed widely in sludge drying practices, which negatively impacts the sludge drying efficiency. This paper was aimed at evaluating the stickiness characteristics of sludge when the sand content of sludge increases during the rainy season, and carrying out stickiness modification experiments on high sand content sludge. The results indicated that the sand content was significantly positively correlated with the stickiness of sludge. During drying process, the adhesion force and cohesion force of sludge decreased with the increase of drying temperature, and the adhesion force was consistently greater than the cohesion force in every group. The sludge stickiness was reduced after ultrasonic treatment and calcium oxide modification, but the reduction effect of sodium dodecyl sulfate on sludge stickiness was not good. This study confirmed the effect of sand content on sludge stickiness, and the stickiness of sludge with high sand content can be reduced by modifier. These findings contribute to our understanding of the stickiness of sludge with high sand content in the rainy season and provide valuable insights for the optimization of sludge drying process. [ABSTRACT FROM AUTHOR]

Developing functional adhesives combining strong adhesion, good recyclability and diverse harsh‐condition adaptability is a grand challenge. Here, we introduce a general dendritic molecule doping strategy to activate commercial polymers into a new family of supramolecular adhesives integrating high adhesion strength, ultralow temperature, water resistant and multi‐reusable properties. Our method involves rational design of a new rigid‐flexible coupled dendritic molecule—M4C8OH as a versatile dopant, while simple M4C8OH doping into commercial polymers can modulate internal and external non‐covalent interaction to enable H‐bonding enhanced interchain cross‐linking for tough cohesion along with enhanced interphase interaction. This endows 20 wt % M4C8OH‐doped polycaprolactone (PCL) adhesives (PCL‐M4C8OH) with improved adhesion strength on various substrates with the maximum increase up to 2.87 times that of PCL. In particular, the adhesion strengths of PCL‐M4C8OH on polymethyl methacrylate at 25 °C and −196 °C reach 4.67 and 3.58 MPa—1.9 and 2.3 times those of PCL and superior to diverse commercial adhesives and most reported adhesives. PCL‐M4C8OH also displays markedly‐improved multi‐usability and tolerance against ultralow temperature and diverse wet environments. Mechanism studies reveal the crucial role of M4C8OH molecular structures toward superior adhesion. Our method can be expanded to other polymer matrices, yielding diverse new supramolecular adhesives. [ABSTRACT FROM AUTHOR]

To explore the effect of acid rain corrosion on the cohesion performance of asphalt and its mechanism, graphene oxide (GO) was used to modify epoxy asphalt and 70# base asphalt, TAFPACK Super (TPS) high viscosity asphalt and epoxy asphalt were used as the control group, the periodic dry–wet cycle immersion test was used to simulate the acid rain environment to study the effect of acid rain on the physical properties, composition, cohesion and adhesion between different asphalt binders and aggregates. Furthermore, combined with aging test, the aging resistance of each asphalt after acid corrosion was investigated. The results show that acid rain corrosion can significantly decrease the adhesion between asphalt and aggregates and the cohesion of asphalt itself, resulting in serious moisture damage of asphalt. GO modified epoxy asphalt has better acid rain corrosion resistance than other asphalt. GO improves the cross-linking density between asphalt molecules. The polar groups and low shrinkage thermosetting resin of GO modified epoxy asphalt make it has excellent adhesion and high cohesion, which can effectively resist moisture erosion, peeling and temperature stress cracking, thus effectively resist the corrosion of acid rain. Aging deteriorates the performance of asphalt binder and decreases its acid corrosion resistance. GO modified epoxy asphalt can effectively inhibit the aging of asphalt binder, thus resisting the deterioration caused by aging. [ABSTRACT FROM AUTHOR]

Zeolite foamed asphalt - warm mix mixture (ZFA-WMM) has been applied in large quantities in asphalt pavement, however, a lower construction temperature, residual zeolite water and zeolite minerals have different effects on the cohesion and adhesion properties of zeolite foamed asphalt (ZFA), which indirectly affects the water stability of its mixture. This study analyzed the interface behavior in ZFA-WMM using molecular dynamics simulation. First, the molecular model of ZFA was constructed, and its thermodynamic properties were calculated and compared with experimental values and related simulated values to validated the reasonable of model. Then, the interface models of ZFA-aggregate (quartz and calcite) and ZFA-ZFA were established, simulating the effects of the zeolite mineral dosage, temperature, and interface moisture (residual zeolite water) content on the cohesion and adhesion of ZFA. Furthermore, the occurrence mode of cohesion or adhesion failures in ZFA-WMM were predicted by comparing the ZFA-aggregate adhesion work with ZFA cohesion work. The simulation results indicated that as the zeolite mineral dosage increased, the ZFA cohesion and ZFA-calcite adhesion increased, while ZFA-quartz adhesion first grew and then dropped, reaching its maximum at 9.4 % zeolite mineral dosage. Under the pavement operating temperature range (-15°C∼65°C), higher pavement temperatures are beneficial to ZFA-aggregate adhesion; the cohesion of ZFA first increases and then decrease as temperature rises, reaching its maximum at 25℃. The larger the interface moisture content, the higher the possibility of water separating ZFA from the aggregate surface and the water sensitivity of ZFA-WMM. The ZFA-WMM is prone to adhesion failure, especially at higher zeolite dosages.

Hydrogel adhesives exhibit great potential in various biomedical fields such as tissue sealing and soft robotics. However, the high‐water content and defective network structures of these hydrogel adhesives result in low intrinsic mechanical strength, severely impeding their application. In this study, it is reported that the strong hydrogel adhesive strength can be achieved when a balance is established between adhesive forces and cohesive forces. Based on this principle, a new double network (DN) design is created to combine an adhesive polyvinyl alcohol (PVA) as the first network with a flexible sodium alginate (SA) as the second network. A delicate balance is achieved between cohesion and adhesion by adjusting the ratio between the first rigid adhesive network and the second flexible network. As a result, this balanced DN hydrogel adhesive exhibits a strong tissue adhesion strength, approximately three times higher than that in the non‐balance situation. [ABSTRACT FROM AUTHOR]

The effect of coating a flat blade surface with titanium nitride nano coatings (TiN), nano tantalum carbide (TaC), Fiberglass (Glass Fiber-Reinforced Polymer) (GFRP), Galvanized Steel (GAS), and St37 (SST37) was investigated in order to decrease the adhesion of soil on tilling tools, external friction and, ultimately, the draft force. The soil tank, which was filled with soil of the desired conditions, was pulled on the bearing on the rail. A S-shaped load cell was used to measure the draft force. Tests were conducted at a distance of 2 m and speeds of 0.1, 0.2, and 0.3 m·s−1 at a depth of 10 cm. A model based on input factors, including blade travel speed, rake angle, and cohesion and adhesion of soil–blade, was developed in an adaptive neuro-fuzzy inference system (ANFIS), and draft force was the output parameter. To verify the performance of the developed model using ANFIS, a relative error(ε) of 6.1% and coefficient of determination (R2) of 0.956 were computed. It was found that blades coated with Nano (TiN-TaC), due to its hydrophobic surface, flatness, and self-cleaning properties, have considerable ability to decrease adhesion in wet soils and showed a linear relationship with draft force reduction. [ABSTRACT FROM AUTHOR]

The comprehensive approach using both pull-off tensile and scratch tests provided a detailed understanding of the adhesion and cohesion properties of the 3D-porous calcium phosphate (CaP) coatings deposited on a Ti substrate by the ultrasound-assisted micro-arc oxidation (UMAO) method. Using the pull-off tensile test which takes into account tensile stresses directed normally to the coating surface, it was found that the ultrasound (US) employing during the the micro-arc oxidation (MAO) process led to a slight decrease in the adhesion of the coating to the substrate from 23.4 to 19.3 MPa as well as to a change in the failure mechanism from the cohesive type characteristic for the control MAO coatings to the adhesive-cohesive type for the UMAO coatings. On the contrary, the results of the scratch test, which takes into account compressive stresses directed normally and tangentially to the coating surface, showed that the US employed during the MAO process led to an increase in the critical loads LC2 and LC3 to 6.7 and 30.6 N, respectively, promoting the adhesive-cohesive and adhesive failures of the coatings. Thus, the US employed during the MAO process led to an increase in the critical shear stresses of the UMAO coatings, thereby increasing their abrasion resistance. [ABSTRACT FROM AUTHOR]

Transdermal drug delivery offers a promising alternative for administering medications like ibuprofen, known for its analgesic and anti-inflammatory properties, with reduced gastrointestinal side effects compared to oral administration. This study explored the potential synergistic effects of combining ibuprofen with lavender essential oil (LEO) in transdermal patches. The composition of LEO was analyzed, revealing predominant compounds such as linalyl acetate and linalool, which are known for their analgesic and anti-inflammatory properties. The physicochemical properties of the patches were investigated, indicating improved cohesion with the addition of LEO. Additionally, thermal stability assessments demonstrated enhanced stability with LEO incorporation with an increase in onset decomposition temperature from 49.0 to 67.9 °C. The antioxidant activity of patches containing LEO was significantly higher with a free radical scavenging ability of 79.13% RSA compared to 60% RSA in patches without LEO. Release and permeation studies showed that patches with LEO exhibited an increased permeation of ibuprofen through the skin with 74.40% of the drug released from LEO-containing patches compared to 36.29% from patches without LEO after 24 h. Moreover, the permeation rate was notably faster with LEO, indicating quicker therapeutic effects. The inclusion of LEO in transdermal patches containing ibuprofen holds promise for enhancing drug delivery efficiency and therapeutic effectiveness, offering a potential strategy for improved pain management with reduced side effects. [ABSTRACT FROM AUTHOR]

We know that use, of Concrete is at construction industry is one of important part and comes at first number due to its compressive test, strength and durability. It has capacity to act as a binding material and high capacity to take strength and some other properties. There are many research were going on respective bond of concrete, fatigue, and creep on active level. Another part is as the times goes the strength of concrete will be reduced and may leads to damage and deteriorate it is one of the drawback of the concrete after we should have the need to repair the concrete to increase a structural strength and make a stiffness property improved which leads to safe structure. Our day by day infrastructure has been developed and have facing some problem for bonding between old to new structure and with composite structure are main issue so we need to repair that and make a proper strength to the corresponding structure. A bond which is good helps the engineer to consider monolithic behavior and it also helps in preventing de-icing salts and water to transmit along the interface. The strength and efficiency of a structure Increases with monolithic behavior of the structure. Main concept is the repair is to be done in such a way that bond will acts a it is originally designed. Making bond strength capable to transfer load and forces such as compression, tension, shear will be properly and safely. In concrete patch repairs application we have seen that the repair material plays a vital importance for concrete on Good Adhesion. For determining the bond strength between material and substrate there are several test. Bond strength under combines shear and compressive stresses, bond strength under shear stresses, under tension stresses respectively are the tests. Combine state of stress that combines compression and shear fall under slant shear tests. . In slant shear test we use a cylindrical or a square prism sample made of two identical parts which are bond at an angle of 30° and under axial compression they are tested. Some experimental work is done in this thesis using concrete steel composite material using epoxy based bonding agent and performing slant shear test and finding out bonding strength and durability of the bond. [ABSTRACT FROM AUTHOR]

During the Fukushima Daiichi Nuclear Power Plant (1F) accident, volatile radioactive fission products (FPs) such as Cs-137 were released, which significantly influenced mid- to long-term decommissioning strategies. A substantial amount of the remaining cesium in the pressure vessel may have deposited onto the 304 stainless steel (SS304) steam separators and dryers. This deposited cesium presents a safety hazard during 1F's decommissioning, as it can generate radioactive dust and complicate waste storage. However, the cohesive and adhesive strengths of CsOH-chemisorbed oxide scales, crucial for understanding the release of cesium-bearing particles from SS304 surfaces, remain undefined. In this study, we explore how CsOH chemisorption affects the cohesive and adhesive strengths between oxide scales and SS304 substrates using a scratch tester. Our tests revealed that cracks formed at approximately the same load, but the overall cohesive strength of the oxide scales decreased following CsOH chemisorption. Furthermore, the transition from cracks to bulk separation occurred more rapidly in CsOH-chemisorbed SS304 substrates, especially those with lower silicon content. Finally, we found that adhesive failure could not be achieved even at 70 N, suggesting that the deposited cesium cannot be completely removed from SS304 during the decommissioning of 1F. [ABSTRACT FROM AUTHOR]

This paper investigated the upcycling process of thermoplastic waste polystyrene (WPS) into thermosetting particleboard adhesive using two cross-linkers, namely methylene diphenyl diisocyanate (MDI) and maleic anhydride (MA). The WPS was dissolved in an organic co-solvent. The weight ratio of WPS/co-solvent was 1:9, and 10% of cross-linkers based on the WPS solids content were added subsequently at 60 °C under continuous stirring for 30 min. The adhesive properties, cohesion strength, and thermo-mechanical properties of WPS-based adhesives were examined to investigate the change of thermoplastic WPS to thermosetting adhesives. The bonding strength of WPS-based adhesives was evaluated in particleboard made of sengon (Falcataria moluccana (Miq.) Barneby & J.W. Grimes) wood and rice straw particles at different weight ratios according to the Japanese Industrial Standard (JIS) A 5908:2003. Rheology and Dynamic Mechanical Analysis revealed that modification with MDI and MA resulted in thermosetting properties in WPS-based adhesives by increasing the viscosity at a temperature above 72.7 °C and reaching the maximum storage modulus above 90.8 °C. WPS modified with MDI had a lower activation energy (Ea) value (83.4 kJ/mole) compared to the WPS modified with MA (150.8 kJ/mole), indicating the cross-linking with MDI was much faster compared with MA. Particleboard fabricated from 100% sengon wood particles bonded with WPS modified with MDI fulfilled the minimum requirement of JIS A 5908:2003 for interior applications. [ABSTRACT FROM AUTHOR]

The article describes new silicone self-adhesive adhesives modified with the addition of talc. The obtained self-adhesive materials were characterized to determine their adhesive properties (adhesion, cohesion, and adhesion) and functional properties (pot life of the composition, shrinkage, and thermal properties of adhesives). Novel materials exhibited high thermal resistance above 225 °C while maintaining or slightly reducing other values (adhesion, cohesion, shrinkage, and tack). Selected composition: T 0.1 was used to prepare self-adhesives in industrial-scale production. Moreover, conducted test results revealed that the addition of talc delayed the thermal decomposition of the adhesive and provided reduced intensity of smoke emissions during combustion as well as the flammability of the adhesive layer. [ABSTRACT FROM AUTHOR]

The numerical simulation of surface tension is an active area of research in many different fields of application and has been attempted using a wide range of methods. Our contribution is the derivation and implementation of an implicit cohesion force based approach for the simulation of surface tension effects using the Smoothed Particle Hydrodynamics (SPH) method. We define a continuous formulation inspired by the properties of surface tension at the molecular scale which is spatially discretized using SPH. An adapted variant of the linearized backward Euler method is used for time discretization, which we also strongly couple with an implicit viscosity model. Finally, we extend our formulation with adhesion forces for interfaces with rigid objects. Existing SPH approaches for surface tension in computer graphics are mostly based on explicit time integration, thereby lacking in stability for challenging settings. We compare our implicit surface tension method to these approaches and further evaluate our model on a wider variety of complex scenarios, showcasing its efficacy and versatility. Among others, these include but are not limited to simulations of a water crown, a dripping faucet, and a droplet toy. [ABSTRACT FROM AUTHOR]

In solving the problem of energy and resource conservation in transport, polymer composites are of paramount importance. Polymer composite using makes it possible to significantly improve the mechanical properties of the materials and simultaneously to increase the durability of the parts of transport machines. The authors of this article focus on the substantiation of introducing the modifier 4.4'-methylenebis(2-methoxyaniline) with low concentrations into the epoxy resin. Such materials are characterized by increased mechanical strength and the ability to withstand static, dynamic stresses, as well as impact loads, since the values of the properties are: bending stresses at bending - σ = 51.2 to 54.4 MPa, modulus of elasticity at bending - E = 3.0 to 3.2 GPa, impact toughness is W = 8.8 to 9.0 kJ/m2. The obtained results of experimental studies of the composite materials properties are in good agreement with the results of testing samples by optical microscopy, which indicates their reliability. [ABSTRACT FROM AUTHOR]

In this study, the direct shear test and model pullout test results are presented to assess the impact of soil fines content and shear resistance characteristics of the pile–soil interface on the pullout resistance of drilled shafts. The direct shear test on the soil–pile interface was conducted based on the pile surface simulated using sandpaper with three roughness types (#24, #40, and #400) and varying fines content. The direct shear test results of soil showed that the internal friction angle decreased by about 29% and the cohesion increased by about 110% when the fine powder content increased from 5% to 30%. Specifically, in the case of soil–sandpaper (#24), the interface friction angle decreased by about 31%, and the adhesion increased by about 16%. The sandpaper with a roughness of #40 and #400 also showed a similar trend. Normalizing the shear strength parameters from the direct shear test demonstrated an intersection between the normalized curves of the friction angle and cohesion (or adhesion) within a specific fines content range. This suggests that shear strength parameters play a significant role based on fines content. Analyzing the normalized index using model pullout test results indicated the necessity to evaluate the contribution of friction angle and cohesion (or adhesion) of the shear surface, taking into account the fines content of the soil for predicting pile pullout resistance. [ABSTRACT FROM AUTHOR]

A digital model is proposed to describe the matrix–fiber interaction in a polymer composite, taking account of adhesion and cohesion. Specifics of adhesive–cohesive interactions are described. [ABSTRACT FROM AUTHOR]

The application of pressure-sensitive adhesives (PSAs) in transdermal drug delivery systems (TDDSs) is limited. Insufficient cohesion in TDDS can lead to cold flow, patch displacement, dose inaccuracies, and the ‘dark ring’ phenomenon. To address these issues, we developed a semi-interpenetrating network (semi-IPN) PSA using a 2-hydroxyethylacrylate-modified acrylic copolymer as the linear polymer and poly[tri(propylene glycol) diacrylate] as the cross-linked network. Semi-IPN PSAs have better mechanical properties compared to traditional PSAs. The cohesion of the semi-IPN PSA was 31 times and 1.6 times that of commercially available DURO-TAK®87-2287 and DURO-TAK® 87–4098, respectively, and the cold flow of the semi-IPN PSA was significantly reduced. Furthermore, the semi-IPN PSA adhered to the human forearm for longer time and did not exhibit the ‘dark ring’ phenomenon after removal. When loaded with flurbiprofen, the semi-IPN PSA was found to maintain high levels of drug release and skin permeation amount, and flurbiprofen loading did not affect its superior cohesive performance. In conclusion, the innovative application of the semi-IPN PSA for TDDS showed excellent mechanical properties, effective adhesion to the skin without irritation, and highly effective drug release. These findings indicate that the use of the semi-IPN is both simple and highly effective for TDDS.

In solving the problem of energy and resource conservation in transport, polymer composites are of paramount importance. Polymer composite using makes it possible to significantly improve the mechanical properties of the materials and simultaneously to increase the durability of the parts of transport machines. The authors of this article focus on the substantiation of introducing the modifier 4.4'-methylenebis(2-methoxyaniline) with low concentrations into the epoxy resin. Such materials are characterized by increased mechanical strength and the ability to withstand static, dynamic stresses, as well as impact loads, since the values of the properties are: bending stresses at bending - σ = 51.2 to 54.4 MPa, modulus of elasticity at bending - E = 3.0 to 3.2 GPa, impact toughness is W = 8.8 to 9.0 kJ/m2. The obtained results of experimental studies of the composite materials properties are in good agreement with the results of testing samples by optical microscopy, which indicates their reliability.

The electrosteric interaction energy for a charged hydrogel and hard plane, and between two charged hydrogels is derived in the Debye-Hückel approximation. This is combined with a van der Waals potential that explicitly addresses the Hamaker constant for the solvent-mediated hydrogel interactions. Then, in the Derjaguin approximation, DLVO-type interaction potentials are provided for hydrogel and hard/rigid spheres, accounting for elastic deformation that accompanies adhesion. As examples, this furnishes the energy for cohesion of soft polyelectrolyte microspheres, and provides a quantitative interpretation for the adhesion of rigid latex spheres to a soft deformable hydrogel, as reported by Sato et al. (Sato et al. 2017 Sci. Rep. 7, 1-10 (doi:10.1038/s41598-017-06257-1)). The theory demonstrates that weak van der Waals attraction of hydrogels is readily balanced by electrosteric interactions, e.g. making colloidal hydrogel dispersions less stable than their rigid-particulate counterparts. [ABSTRACT FROM AUTHOR]

The bonding property plays a crucial role in the durability of the asphalt mixture. Warm-mix asphalt (WMA) commonly is used for energy-efficient pavements. The addition of warm-mix additives makes the behavior of the bonding property more complex, especially its atomic-level mechanism. To better clarify the multiscale behavior of WMA bonding property, three typical WMA binders, namely Sasobit-modified asphalt binder, Evotherm-modified asphalt binder, and waste cooking oil (WCO)-modified asphalt binder were selected. The binder bond strength (BBS) test was carried out to evaluate the bonding fracture type and bonding strength. Based on molecular dynamics (MD) simulation, cohesion and adhesion work, radial distribution function (RDF), mean square displacement (MSD), and molecule polarity were calculated to reveal the mechanism. The tensile strength ratio (TSR) of corresponding mixtures was calculated to perform mixture-level characterization. Strong correlations (R -squared >0.9) were found between BBS testing results and interaction work derived from the MD simulation (for both cohesion and adhesion behavior). In addition, the fracture type in the BBS testing can be predicted accurately by the MD simulation. BBS tests found higher cohesion strength and lower adhesion strength with the addition of Sasobit, whereas adding Evotherm and WCO resulted in lower cohesion strength and higher adhesion. The change in cohesion is explained by RDF calculations. Sasobit wax encourages the stacking of asphaltene molecules, whereas Evotherm and WCO aid in its dispersion. MD simulation also confirmed that molecule polarity plays an important role in the adhesion work (R -squared >0.9). Polar functional groups in Evotherm and WCO facilitate better asphalt–mineral adhesion. Nonpolar Sasobit weakens asphalt–mineral adhesion. MSD calculation indicated that diffusion behavior is governed by the combination of molecular mass and adhesion behavior. Molecules with larger molecular mass and stronger adhesion exhibit slower diffusion. Mixture-level evaluation (tensile strength ratio) correlated well with adhesion work (R -squared = 0.822) but poorly with cohesion work (R -squared = 0.667), indicating that adhesion is more important than cohesion in water-damage resistance. [ABSTRACT FROM AUTHOR]

Concrete and reinforced concrete building structures (for example, such as tunnels) lose carrying ability in case of high‐temperature fire action. The aim of the research is to study the prevention of reinforced concrete structures (for example, such as tunnels) under fire action in case of using the proposed coating based on the alkaline aluminosilicate binder, which would not consist of organic components dangerous to health. The ratios between constituent oxides in the binder which ensure the ability to bloat the coating under fire action were determined. The performance properties of developed fire protective coating were defined after artificial aging (cycles of alternate drying and cooling) and fire action: bloating factor ‐ 2.0...5.1, adhesion strength ‐ 6.6...8.0 MPa, compressive strength ‐ 2.3...4.5 MPa, cohesive strength of 1.2...1.5 MPa, thermal conductivity coefficient ‐ 0.042...0.066 W/m‐°C, total porosity ‐ 92...97 %. The temperature at which the coating starts to bloat = 200...250 °C has been developed. The results of the test held in the open air suggested drawing a conclusion that with a coating thickness of 6 mm protection of the reinforced concrete from fragile fracture and from plastic deformations in the metal of the reinforcement they provided under fire exposure for a period of 3 hours. [ABSTRACT FROM AUTHOR]

Phenol-formaldehyde (PF) resin is one of the most well-known adhesives for exterior use. PF adhesive is one of the commercial thermoset polymers that is used extensively due to its many benefits. This study investigated the influence of different types and levels of catalysts, i.e., NaOH and CaCO3 at 1% and 5% based on the solids content of PF resin on the adhesive properties, adhesion, and cohesion strength of PF resin. The results show that the catalyst type significantly influenced the PF adhesive viscosity and pH. Furthermore, the catalyst level significantly affected the PF adhesive's solids content, viscosity, and gelation time. The cohesion strength of PF-CaCO3-1% was more significant than the PF control at 75 °C. According to the DMA analysis, the mixed PF-NaOH-5% provided the highest storage modulus, followed by the PF-CaCO3-1%, with values that were not statistically different from one another. The adhesion strength of PF-CaCO3-1% was the highest, whereas the adhesion strength of the PF control was the lowest, as confirmed by the cohesion strength. According to the findings, adding CaCO3-1% as a catalyst of PF resin would result in better adhesive adhesion and cohesion properties for wood composites in the future. [ABSTRACT FROM AUTHOR]

The effect of the concentration of technical carbon on the peel resistance of nanocomposites based on low-density polyethylene, high-density polyethylene, polypropylene, a compatibilizer, and polyolefins filled with 5.0 wt % aluminum and copper is considered. High density polyethylene modified with maleic anhydride and propylene are used as a compatibilizer. The concentration of technical carbon is varied in the limits of 0–40 wt %. It has been established that polyolefin nanocomposites with 5–15 wt % technical carbon exhibit relatively high peel resistance. The main factors affecting the formation of an adhesion contact have been found. [ABSTRACT FROM AUTHOR]

The complex three-phase composition of lithium-ion battery electrodes, containing an ion-conducting pore phase, a nanoporous electron-conducting carbon binder domain (CBD) phase, and an active material (AM) phase, provides several avenues of mesostructural engineering to enhance battery performance. We demonstrate a promising strategy for engineering electrode mesostructures by controlling the strength of adhesion between the AM and CBD phases. Using high-fidelity, physics-based colloidal and granular dynamics simulations, we predict that this strategy can provide significant control over electrochemical transport-relevant properties such as ionic conductivity, electronic conductivity, and available AM-electrolyte interface area. Importantly, the proposed strategy could be experimentally realized through surface functionalization of the AM and CBD phases and would be compatible with traditional electrode manufacturing methods.

With the recent advancement in emerging biomedical engineering fields, such as tissue engineering, regenerative medicine, and wearable medical devices, there is a growing need to develop adhesives that can function not only as tissue sealants for surgery and wound closure, but also attach various biomaterials and devices. These "bioadhesives" should allow refined control of cohesive and adhesive properties, while significantly improving the biocompatibility and biodegradability. For this reason, bioadhesives are being developed using a wide range of natural biopolymers with proven biocompatibility that can also impart multifunctionality either using their innate properties and/or obtained via various chemical modifications. In this review, state-of-the-art bioadhesives made from multifunctional biopolymers are introduced. Natural biopolymers are increasingly utilized to develop adhesives for biomedical applications, including wound healing and biomedical devices, for their favorable physicomechanical properties as well as their proven biocompatibility. Furthermore, various modification strategies are often employed to impart multifunctionality. In this review, recent development and notable examples of bioadhesives based on multifunctional biopolymers are highlighted. [ABSTRACT FROM AUTHOR]

Assuming a Dugdale cohesive zone, recently a simple Euler beam model has been proposed to understand the transient peeling on an elastic film from a rigid substrate at 90° from the substrate. The model also shows with sufficiently high bending stiffness, a peak force emerges larger than the Rivlin–Kendall steady-state value, scaling with the fourth root of bending stiffness. From the maximum force during peeling, and its steady-state value which is given by the Rivlin–Kendall well-known model, a simultaneous characterisation of the most important cohesive properties (cohesive strength and toughness of the interface) is obtained from a single test. This maximum force eventually saturates at a value which depends on cohesive strength alone. The presence of possibly inevitable initial cracks at the edge of the interface obviously reduces the peak force, and here, we give a simple closed-form approximate solution for this case too. [ABSTRACT FROM AUTHOR]

The plywood industry's sustainability, performance, and production costs depend on wood adhesives and the hot pressing technique. In this investigation, a cold-setting plywood adhesive based on polyvinyl alcohol (P), tannin (T), and hexamine (H) was produced. The physical and mechanical properties of plywood were examined at different formulations such as tannin concentration (10% and 20%), hexamine content (5%, 10%, and 15%), and cold-pressing time (3, 6, 12, and 24 h). This study showed that high tannin and hexamine content also increased the solids content, but decreased the average viscosity of the adhesive. Markedly, the cohesion strength of PTH-based adhesives increased from 5.57 Pa at 1/s to 1411.6 Pa at 400/s shear rate, regardless of the adhesive formulation. The shear modulus subsequently decreased as a function of the shear rate and increased with a higher tannin and hexamine content. This study revealed that the higher tannin and hexamine content and longer cold-pressing times could produce plywood with the tested adhesive that met the Japanese standard strength requirements. A combination of PTH-based adhesive prepared with formula 2 and 24 h cold-pressing resulted in the highest TSS value of 1.42 MPa, MOR values of 88.7 MPa, MOE values of 14,025.6 MPa, and wood failure of 47.2%. This study showed the possibility of fabricating eco-friendly plywood panels bonded with PTH-based adhesive using the cold-pressing process as an alternative to conventional plywood. [ABSTRACT FROM AUTHOR]

The influence of the filler concentration and the type of compatibilizer on the peeling resistance of polypropylene-based nanocomposites is considered. The filler was aluminum and copper nanoparticles, the substrate was copper and aluminum foil, and the compatibilizer was a polypropylene graft copolymer with 5.6 wt % of maleic anhydride and a polypropylene graft copolymer with 7.0 wt % of methacrylic acid. The filler concentration was varied within 5–50 wt %. It was found that polypropylene nanocomposites containing 10 wt % of filler have relatively high values of peel resistance. The main factors influencing the mechanism of adhesive contact and the type of adhesive destruction, which result in high values of resistance to peeling of the adhesive from the foil surface, are revealed. [ABSTRACT FROM AUTHOR]

In the presented work, organophilized montmorillonites (OMMT) with selected quaternary ammonium compounds (QAC) with different chemical structure ((trioctylmethylammonium chloride—A336, dimethyloctadecyl[3-trimethoxysilyl)propyl]ammonium chloride—D, cetyltrimethylammonium bromide—CTAB, 2-methacryloxyethyltrimethylammonium chloride—MOA) were obtained and used as fillers for physically modified silicone pressure-sensitive adhesives (Si-PSA). Before OMMT addition into Si-PSA matrix, they were analyzed via TGA and XRD techniques. Type of chemical structure of QAC affected d-spacing of OMMT. New self-adhesive materials were obtained based on prepared Si-PSA compositions by adding the obtained fillers to the polymer matrix. New tapes exhibit a good level of useful properties as adhesion, cohesion, and tack—the values did not change or slightly decreased; in addition, the tapes with addition of OMMT showed high thermal resistance reaching the measuring limit of the test equipment—to 225 °C. [ABSTRACT FROM AUTHOR]

Adhesins (adhesive proteins) help bacteria stick to and colonize diverse surfaces and often contribute to virulence. The genome of the bacterial wilt pathogen Ralstonia solanacearum (Rs) encodes dozens of putative adhesins, some of which are upregulated during plant pathogenesis. Little is known about the role of these proteins in bacterial wilt disease. During tomato colonization, three putative Rs adhesin genes were upregulated in a DphcA quorum-sensing mutant that cannot respond to high cell densities: radA (Ralstonia adhesin A), rcpA (Ralstonia collagen-like protein A), and rcpB. Based on this differential gene expression, we hypothesized that adhesins repressed by PhcA contribute to early disease stages when Rs experiences a low cell density. During root colonization, Rs upregulated rcpA and rcpB, but not radA, relative to bacteria in the stem at mid-disease. Root attachment assays and confocal microscopy with DrcpA/B and DradA revealed that all three adhesins help Rs attach to tomato seedling roots. Biofilm assays on abiotic surfaces found that Rs does not require RadA, RcpA, or RcpB for interbacterial attachment (cohesion), but these proteins are essential for anchoring aggregates to a surface (adhesion). However, Rs did not require the adhesins for later disease stages in planta, including colonization of the root endosphere and stems. Interestingly, all three adhesins were essential for full competitive fitness in planta. Together, these infection stage-specific assays identified three proteins that contribute to adhesion and the critical first host-pathogen interaction in bacterial wilt disease. [ABSTRACT FROM AUTHOR]

Advanced packaging solutions require insulation and passivation materials with exceptional properties which can also fulfill the reliability needs of electronics devices such as MEMS, sensors or power modules. Since bonding (cohesive/adhesive) properties of packaging coatings are very important for reliable functioning of electronics devices, the bonding of aliphatic fluorinate-4 (AF4) parylene coatings was assessed in this work. As there is a lack of data regarding its bonding towards different substrates, pull-off tests of 1.6 and 2.5 μm thick AF4 coatings on silicon (Si) and glass (SiO2) substrates were performed. These showed a clear difference in the pull-off F/s curves between the AF4 coatings on Si and SiO2 substrates. This difference is parameterized by the pull-off energy, which will be presented in this work. To further understand the origin of the distinction in the pull-off energies between the AF4-Si and AF4-SiO2 samples and subsequently the cohesive/adhesive properties, mechanical and structural characterization was conducted on the AF4 coatings, where a clear difference in the E-modulus and crystallinity was observed. The Si and SiO2 wafers were shown to facilitate the CVD growth of the AF4 film distinctively, which likely relates to the divergent thermal properties of the substrates. Understanding of the cohesive/adhesive properties of AF4 coatings on different substrate materials advances the usage of the AF4 in electronics packaging technologies. [ABSTRACT FROM AUTHOR]

The dynamics of cohesive particles and their tendency to adhere to surfaces present significant challenges in various industrial processes. A profound understanding of adhesive and cohesive forces is crucial for the optimized design of continuous manufacturing systems, aiming to effectively mitigate flow-related issues such as blockages, segregation, irregular flow patterns, and flooding. In this study, the adhesive forces of eight excipients using four distinct methodologies were systematically evaluated, i.e., colloidal atomic force microscopy, contact angle measurement, drop tester, and centrifugation for comparative analysis. Qualitative assessments of cohesion, including the angle of repose, rotating drum, Carr index, and Hausner ratio were additionally implemented to corroborate the findings. By evaluating these methodologies in conjunction, the strengths and limitations of each approach can be explored. This comparison paves the way for a more nuanced understanding of particle adhesion dynamics and can aid in selecting the most suitable technique for specific applications. [Display omitted] • Four distinct particle-scale adhesion measurement techniques were quantitatively compared. • Particle-scale adhesion measurement were assessed against bulk scale cohesion characterization of eight excipients. • The strengths and limitations of each technique were evaluated, which aids in process design. • Colloid-AFM offers detailed insights into particle-scale adhesion, cohesion, surface roughness, and mechanical properties. [ABSTRACT FROM AUTHOR]

• Cake-to-fabric adhesion and cake cohesion tests were carried out using special test rigs for a tensile testing machine directly subsequent to laboratory filter press tests. • Filtration process parameters (filtration pressure, air blow pressure, and duration of the air blow) can be used to control the properties of the filter cake. • Residual water content and saturation decrease with an increase of the three process parameters, adhesion and cohesion increase. • A simplified mathematical model was developed which describes the desaturation behavior. Copper mining produces immense amounts of tailings due to low ore grades. These residues are increasingly dewatered by filtration in recessed plate filter presses to ensure safer storage and high recovery of water. The process parameters filtration pressure, desaturation time, desaturation pressure and cake thickness have a significant influence on achieving water content as well as bulk material stability specifications and maintaining operation performance, especially with regard to cake detachment. In this study, copper tailings filtration tests in a laboratory filter press and directly connected measurements of cake-to-fabric shear adhesion as well as filter cake shear cohesion were carried out. It is shown that optimization of cake properties with regard to residual water content, suitability for detachment and bulk material stability by specific adjustment of the filtration and post-treatment parameters is possible. Furthermore, implementation of a mathematical model allows water content, cake saturation, cake-to-fabric shear adhesion and cake shear strength prediction dependent on filter cake desaturation time and pressure for tailings filtration applications in recessed plate filter presses. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-growing biomimetic functional hydrogel particles (SG-BFHPs) developed for Conformance Control. • The SG-BFHPs exhibited higher Frr (10.7–11.8) and better scour resistance. • AFM experiments show that SG-BFHPs has stronger adhesion between particles or rock surface. • SG-BFHPs distributed in irregular structure in fractures and adsorbed on the wall, which can adjust fracture channel. Hydraulic fracturing is gradually becoming a common approach for enhancing the oil production from tight reservoirs. Blocking agents such as soft particle systems are necessary as a means of conformance control to mitigate the side effect of reservoir heterogeneity due to hydraulic fracturing. In this work, a novel technique based on the mussel biomimetic concept is proposed to generate self-growing biomimetic functional hydrogel particles (SG-BFHPs). The fracture conformance control capacity of the products is evaluated, and the results show that multi-scale (0.5–3.0 mm) SG-BFHPs can cohere and grow at the reservoir condition, and the median agglomerated particle size can increase by 20–25 times. High flow resistance (Frr = 10.7–11.8), facilitated by the higher adhesion between the biomimetic particles and the pore walls, can be established by SG-BFHPs while maintaining a good injectivity. In the single-fracture model, the increased oil recovery by SG-BFHPs is about 12.2 %, and in the matrix-fracture model can be increased from 9.2 %–13.5 % to 25.8 %–28.8 %. AFM experiments show that SG-BFHPs have stronger adhesion between particles or rock surface than conventional hydrogel particles. After conformance control of SG-BFHPs, the particles are distributed in an irregular structure in the fractures and adsorbed on the fracture wall under the effect of inter-particle cohesion and adhesion, which can realize fracture channel adjustment by the particle self-growing. The SG-BFHPs studied in this paper provide valuable insights for the development of dispersed particle gel, which is of great significance in improving oil recovery in tight reservoirs. [ABSTRACT FROM AUTHOR]

This in vitro study evaluated the surface hydrophobicity of 3D-printed denture base resin exposed to either an extended post-curing light exposure time or a sandblasting procedure. MATERIALS AND METHODS: Disk-shaped samples (diameter × height: 10 mm × 3 mm) were 3D-printed with stereolithography SLA technology using the denture-base resin. Samples were divided into three groups: control, extended UV-post-curing, and sandblasted. The surface roughness parameters for each group were calculated, and the surface hydrophobicity was evaluated by measuring the drop contact angle. Analysis was done using the T-test; significance was when p < 0.05. RESULTS: The comparison of surface roughness parameters showed significant differences between the control group and the sandblasted group (Sa: p = 0.001, Sz: p < 0.001, Str: p < 0.001, Spc: p = 0.044) as well as between the extended-cure group and the sandblasted group (Sa: p = 0.006, Sz: p < 0.001, Str: p < 0.001, Spc: p = 0.036) except for the Sdr measures. The surface hydrophobicity was also statistically lower in the sandblasted group compared to both the control and extended curing groups (p < 0.001). CONCLUSION: The sandblasting procedure created a less hydrophobic surface of the 3D-printed denture base resin, and the altered surface roughness could be a contributor to this observation.

It has been shown that recombinant spidroins rS1/9 and rS2/12 that we previously developed exhibit adhesive properties with respect to both inorganic and organic substrates. It is well known that the adhesive properties of mussel foot proteins are associated with the level of DOPA, which is formed as a result of the post-translational modification of tyrosine residues by the tyrosinase enzyme. Therefore, we used recombinant tyrosinase for in vitro modification of tyrosine residues in the recombinant rS1/9 and rS2/12 spidroins to increase their adhesion capacity. As expected, the conversion of tyrosine residues into DOPA led to an increase in the adhesion properties of these proteins, which was demonstrated in experiments on gluing plates of polyvinyl chloride, aluminum, polylactic acid, and tubular pork bone. The molecules of recombinant spidroins retained their inherent properties to form supramolecular structures, hydrogels (microgels), transparent films, and 3D matrices. Interestingly, tyrosinase-modified proteins exhibited increased cohesion in experiments on bonding different materials in the presence of water. [ABSTRACT FROM AUTHOR]

Ice shedding from the rotating components can cause unacceptable mechanical damage to the engine intake system. Therefore，it is necessary to study the phenomenon of rotating deicing. The ice shedding research can be divided into two parts i. e.，experimental study in the icing wind tunnel and numerical simulation based on the finite element software. The ice shape，mass and density are obtained through experiments under different conditions. The stress distribution of ice on a solid surface is obtained by simulation. The experimental results show that the rime ice formed at a lower temperature is more difficult to lose than the glaze ice formed at a higher temperature. The simulation results show that the cohesion strength of the rime ice is less than its shear adhesion，but the cohesion strength of the glaze ice is greater than its shear adhesion. [ABSTRACT FROM AUTHOR]

To analyze the impacts of composition-associated factors of high-viscosity asphalt mixtures and thermal aging on the cohesion and adhesion characteristics of high viscosity–modified asphalt (HVMA), neat asphalts (NAs), high-viscosity additives, and aggregates were selected, and several HVMAs were first prepared. Then, the prepared HVMAs were subject to contact angle testing, and their cohesion and adhesion behaviors and influencing factors were explored by multifactor orthogonal testing coupled with the surface free energy (SFE) concept. Further, the variations and influencing factors of cohesion and adhesion properties of relevant HVMAs under aging were analyzed in comparison with styrene-butadiene-styrene (SBS)-modified asphalts (SBSMAs) and NAs. Lastly, under aging, the change behaviors of microscopic phases of HVMAs were contrastively investigated using atomic force microscopy (AFM) testing, and the relationship between the microscopic phases and the cohesion and adhesion properties was illustrated. Results showed that NA type, high-viscosity additive dosage and type, and aggregate type notably influenced the cohesion and adhesion of HVMAs, and the high-viscosity additive dosage influenced their cohesion the most. Aging weakened the cohesion and adhesion of asphalts, and the HVMAs possessed the superior cohesion and adhesion at each aging period. Under aging, the NA type, aggregate type, and aging level remarkably affected the cohesion and adhesion of HVMAs, among which the NA type affected their cohesion most prominently. Besides, the aggregate type was the most influential variable on the adhesion of HVMAs whether the HVMAs were aged or not. AFM testing demonstrated that aging reduced the component of microscopic phase structures of HVMAs and the amount of their bee structures, and diminished the surface roughness Ra of asphalt binders; in contrast, aging did not alter the component of microstructural morphology of SBSMAs and NAs. The cohesion and adhesion indexes of HVMAs under aging obeyed the high Pearson correlation and the moderate linear correlation with the Ra index. [ABSTRACT FROM AUTHOR]

Cleaning operations are performed regularly throughout the food industry. This review focuses on the removal of strongly adherent fouling deposits which compromise the performance and hygienic status of equipment and processes. Identifying and understanding the key mechanisms involved in cleaning food deposits is essential for selecting and optimising cleaning protocols. The complexity of these materials has prompted the use of model soil-surface systems for experimental investigations of cleaning. The factors that need to be considered in selecting model soil systems, the techniques used to measure and characterise cleaning, and the formulations that have been used to model food fouling deposits are discussed. Particular focus is given to deposits formed from liquid foods high in protein, starch, sugar and lipids. Biofilms, fouling layers generated in membrane operations and corrosion fouling are not considered. [ABSTRACT FROM AUTHOR]

Our understanding of the surrounding world, from friction to the origin of life, depends on how we imagine the contact interaction of condensed bodies. What are the forces acting in contact with solids? Do they attract (adhesive) or repel (dehesive)? Theory and research at the atomic-molecular level have shown that the force are adhesive, but everyday experiences cast doubt on this conclusion. This article addresses this issue by considering the mistakes made in experimental and theoretical tribology and surface physics. Taking into account the theories of hybridization and dehybridization of electron orbitals and valence bonds, the views on the structure of the surfaces of condensed bodies and the force arising during contact interaction are revised. The influence of van der Waals, hydrogen, covalent, metallic, and ionic bonds on the properties of lubricants is evaluated. The contours of the dehesive-deformation theory of friction and wear are also outlined. [ABSTRACT FROM AUTHOR]

A large number of domestic and foreign scientists were engaged in the wear of the surfaces of the excavating parts of earthmoving machines during their interaction with the ground, as well as the problem of the adhesion of soils on the surface of the working excavating parts of machines and methods of struggle. It is known that the classical theory of digging is based on empirical dependencies obtained experimentally. They allow, basically, to reveal the essence of the process of dredging, but they differ from each other, both in their description and in the number of results. In this article, the authors propose, on the basis of probability theory, theoretical studies of the process of dredging and the interaction of the excavating part with the soil. The authors of previous studies confirm the obtained results. The developed physical model of the interaction of soil particles with the surface of the excavating part during adhesion allows us to reveal the physical cause of the process of wear of the surface of the excavating parts.

Stickiness is the combination of adhesion and cohesion and key characteristic for binders in foods to combine particulates into a coherent mass. We investigated the influence of mixing ratio of pea protein and apple pectin powders (w/w) at pH 6 on stickiness by assessing textural, rheological, and binding properties of a concentrated suspension (25 wt% powder concentration). The elastic but soft texture of a pea protein suspension alone showed cohesive failure with low stickiness in line with limited viscous properties. A pectin suspension also showed low stickiness, but with an adhesive failure, which was due to the hard and stiff nature of the matrix preventing sufficient adhesive interactions. However, mixtures of pea proteins and apple pectin with multiphase morphologies displayed a balanced combination of viscous and elastic properties, which was beneficial for stickiness. In particular, the mixture with 67% pea proteins and 33% apple pectin showed a distinct frequency dependence in their rheological moduli. Viscous properties dominated at low frequencies improving bond formation (adhesion), while elastic properties became more important at high frequencies opposing stress acting against the bond (cohesion). This study highlights the importance of a characteristic viscoelasticity for stickiness of pressure-sensitive adhesives and how it can be tailored through biopolymer mixing.

Pectin is a plant-derived heteropolysaccharide that has been implicated in drug development, tissue engineering, and visceral organ repair. Pectin demonstrates remarkable biostability in a variety of physiologic environments but is biodegradable in water. To understand the dynamics of pectin biodegradation in basic environments, we developed a microfluidics system that facilitated the quantitative comparison of pectin films exposed to facial erosion. Pectin biodegradation was assessed using fluorescein tracer embedded in pectin, trypan blue quenching of released fluorescence, and highly sensitive microfluorimetry. The microfluidic perfusate, delivered through 6 um-pore synthetic membrane interface, demonstrated nonlinear erosion of the pectin film; 75% of tracer was released in 28 h. The microfluidics system was used to identify potential modifiers of pectin erosion. The polyphenolic compound tannic acid, loaded into citrus pectin films, demonstrated a dose-dependent decrease in pectin erosion. Tannic acid had no detectable impact on the physical properties of citrus pectin including adhesivity and cohesion. In contrast, tannic acid weakened the burst strength and cohesion of pectins derived from soy bean and potato sources. We conclude that facial erosion may explain the biostability of citrus pectin on visceral organ surfaces as well as provide a useful method for identifying modifiers of citrus pectin biodegradation. [ABSTRACT FROM AUTHOR]