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Jelly glue made of gelatin is frequently used in the packaging industry. The purpose of this study is to determine whether starch and polyvinyl alcohol (PVA), which were introduced at a 1.0% concentration, could be used to develop with improvement in the performance properties of jelly adhesives that are being prepared. By examining viscosities at different temperatures, pH, water contact angles, differential scanning calorimetry (DSC), tensile strength on wood and setting speed observation on coated paper, and performing pencil hardness tests on films, the effect of adding starch and PVA as a binder on physical, thermal, and mechanical properties were studied. When starch and PVA were added to the jelly glue, DSC data showed a substantial rise in the glass transition temperature, which were further confirmed by film hardness testing. The addition of starch increased the adhesive's viscosities at different temperatures. When compared to an original sample, the tensile strength with starch increased by ~ 74% after 24 h of bonding in a dry environment. The jelly adhesive with starch showed increased in water resistance which was also validated from contact angle test. Unlike PVA-based jelly glue, the hydrogen bonding in starch and gelatin showed superior mechanical properties. This research discusses starch as a potential substitute for the development of jelly adhesive. The technique developed offers an easy and useful path to adhesives with increased water resistance and bonding strength by using starch as a binder. Ecologically sound, sustainable, and economically acceptable were the methods used to increase jelly adhesive's resistance to moisture. The study's overall finding highlights the superior and sustainable adhesive performance of jelly glue based on starch as a packaging adhesive. [ABSTRACT FROM AUTHOR]

UV debonding acrylate pressure-sensitive adhesives (UPSAs) are necessarily applied in the semiconductor industry. To establish a comprehensively understood method is important to detect their bonding and debonding behaviors. In this paper, rheological methods, including Three Interval Thixotropy tests (3ITT) and Tack test modes were used for characterizing series of UPSAs. Vinyl groups were successfully grafted onto the acrylate copolymer chains through isocyanate condensation reactions, which were characterized by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy and gel permeation chromatography. From the maximum normal force in the Tack test modes, UPSAs after UV irradiation showed obvious debonding behaviors in short-time stress analysis. The recovery percentage of the storage modulus in 3ITT tests indicated that 0.6 wt% isocyanate curing agent made the UPSAs good resistance to deformation. Under the limit of 30 wt% pentaerythritol diacrylate (PETA), the rheological adhesion performance of UPSAs increases accordingly with the PETA content, which was also confirmed by 180° peel strength tests. From the microscope images of the wafer surfaces after peeling off the UPSA tapes, rheological characterization methods can help designing UPSAs with clean debonding properties. [ABSTRACT FROM AUTHOR]

Damage and fracture of archaeological potteries not only jeopardize the long-term preservation but also hinder their exhibition. To repair these pottery sherds effectively, this study introduces a novel inorganic phosphate-based adhesive and evaluates its effectiveness through a series of experiments. To determine the optimal base adhesive, the paper investigates the influence of varying weight ratios of the H2O–H3PO4 system and the Al(OH)3–H3PO4 system on properties including tensile lap-shear strength, microstructure, high-temperature resistance and phase composition. However, the original black color of the traditional CuO–phosphate adhesive limits its application. The innovation of this study lies in the addition of nano-TiO2 to the adhesive, which not only improves the bonding strength but also adjusts the color of the adhesive. This study has defined the optimal formulation (i.e., base adhesive = m[Al(OH)3]:m[H3PO4] = 7:100, filler = 10wt% nano-TiO2), and the final product shows no residual acid in adhesives. Additionally, the fracture surfaces are successfully bonded with a high strength of 3.56 MPa. Various ageing tests including dry-thermal ageing, hygrothermal ageing and UV irradiation ageing are conducted to assess the ageing resistance of the inorganic phosphate-based adhesive. The results indicate strong tolerance of adhesive to high temperature and high humidity environment. Preliminary applications in archaeological pottery restoration suggest that the inorganic phosphate-based adhesive offers considerable promise for repairing shattered pottery. [ABSTRACT FROM AUTHOR]

Fiber agglomeration and poor interfacial combination with the matrix restrict the performance of composites. Herein, soybean meal-based adhesives were fabricated via the addition of dialdehyde cellulose (DAC) obtained from waste paper dissolved in an alkali–urea system and oxidized with sodium periodate. Due to the dissolution by the alkali–urea system, DAC dispersed well in the solution and did not aggregate in the adhesive matrix. Because of the oxidation treatment, DAC was crosslinked with the adhesive matrix via a Schiff base reaction. Meanwhile, hydrogen bonds were formed at the interface between the DAC and the adhesive matrix. Plywood with the SM/DAC/PTGE adhesive reached its highest wet bonding strength of 1.27 MPa (4 wt% DAC addition), a 95% increase compared to that with the unmodified SM/PTGE adhesive. Fine DAC-to-SM interfacial bonding and a dense crosslinking network were constructed in the SM/DAC/PTGE adhesive systems. The cycle of reuse for the alkali–urea system in the experiments demonstrated that the preparation method of the cellulose solution was scalable and sustainable. [ABSTRACT FROM AUTHOR]

The research reported here focuses on developing wood adhesive by mixing liquid glucose (LG) and polyvinyl alcohol (PVA) in water. Here, boric acid is used as a crosslinking agent to improve the LG–PVA blend's thermomechanical characteristics. The impact of crosslinking was measured using a variety of analytical techniques, including viscosity testing, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and water contact angle testing. By pouring LG–PVA blends onto Teflon sheets, a film was made. On performance parameters like tensile strength, pencil hardness, and thermal properties like glass transition temperature, the impacts of several variables, such as increasing the amount of LG and boric acid, were examined. In the water contact angle test, the crosslinked blend films showed decreased hydrophilic behavior and increased pencil hardness. The films glass transition temperature (Tg) was positively impacted by the higher BA concentration. For the crosslinking reaction with boric acid, the free hydroxyl groups present in LG and PVA serve as an active sites. Crosslinks between the hydroxyl groups of LG and PVA are expected to take place as a trivalent boron attracts these nucleus-loving groups. FTIR spectrum measurements confirmed the interaction of boric acid with the LG–PVA mixture. The reaction was accelerated by the acidic pH, and its effects were shown in the rise in thermomechanical properties. By lowering the free volumes between the chains, the crosslinking improved cohesion, and as a result, an increase in strength on glued wood specimens was observed. [ABSTRACT FROM AUTHOR]

Water-soluble pressure-sensitive adhesives (PSA) based on acrylic acid and carboxymethyl starch (CMS) have been prepared. The tack and peel adhesion to various paper types (newsprint, hygienic, packing, fax and art paper) as well as dynamic shear adhesion at higher temperatures (70-240 °C) have been tested with the aim of applying such PSA in a form of double-sided splicing tapes for paper industry. For all paper types tested tack and peel adhesion values increased with CMS content (0.1-10 wt% in PSA). The highest tack and peel adhesion values (for the system containing 10 wt% CMS) were noted for fax paper ca. 19.5 N/2.5 cm and 18.3 N/2.5 cm, respectively and the lowest ones for art paper: 14.7 N/2.5 cm and 13.5 N/2.5 cm, respectively. Obtained PSA were completely soluble in water, and the time of water-solubility depended on CMS content, as well as pH value, however it did not exceed 5 min. [ABSTRACT FROM AUTHOR]

The combined approach of classical fingerprinting and DNA profiling is a powerful tool in forensic investigations of latent "touch" traces. However, little attention has been paid to the organic solvents frequently used in dactyloscopic laboratories to facilitate the separation of adhesive evidence prior to fingerprint development and downstream effects on subsequent DNA profiling. In the present study, we tested a selection of adhesive removers (n = 9) and assessed their potential impact on DNA recovery and amplification by PCR. Thereby, we identified and characterized novel PCR inhibitors. All investigated chemicals contain volatile organic compounds that evaporate under normal indoor atmospheric conditions. Exposure to certain solvents resulted in increased DNA degradation, but only if evaporation was prevented. A series of adhesive-removal experiments were conducted with prepared mock evidence (self-adhesive postage stamps affixed to paper envelope) to investigate the impact of treatment time and the location of applied traces on DNA recovery and dactyloscopy, respectively. Due to the early onset of print decomposition, we found that only a short treatment time was compatible with the development of fingerprints on the adhesive side of a stamp. Solvents also removed DNA from the adhesive surface, thus resulting in a marked shift in the substrate distribution of recovered DNA from the stamp to the envelope, but not in the reverse direction. Furthermore, we observed that treatment with conventional fingerprint reagents lead to a significant reduction in the amounts of DNA recovered from stamps, while the additional use of adhesive removers did not significantly enhance this effect. [ABSTRACT FROM AUTHOR]

Background: The use of hemostatic agents by general surgeons during abdominal operations is commonplace as an adjunctive measure to minimize risks of postoperative bleeding and its downstream complications. Proper selection of products can be hampered by marginal understanding of their pharmacokinetics and pharmacodynamics. While a variety of hemostatic agents are currently available on the market, the choice of those products is often confusing for surgeons. This paper aims to summarize and compare the available hemostatic products for each clinical indication and to ultimately better guide surgeons in the selection and proper use of hemostatic agents in daily clinical practice. Methods: We utilized PubMed electronic database and published product information from the respective pharmaceutical companies to collect information on the characteristics of the hemostatic products. Results: All commercially available hemostatic agents in the US are described with a description of their mechanism of action, indications, contraindications, circumstances in which they are best utilized, and expected results. Conclusion: Hemostatic products come with many different types and specifications. They are valuable tools to serve as an adjunct to surgical hemostasis. Proper education and knowledge of their characteristics are important for the selection of the right agent and optimal utilization. [ABSTRACT FROM AUTHOR]

The static friction behavior of an elastic–plastic spherical adhesive microcontact between a rigid flat and a deformable sphere under combined normal and tangential loading is studied by the finite element method (FEM). The contact between the sphere and the rigid flat is assumed to be full-stick, and the sliding inception is related to a loss of tangential stiffness. The intermolecular force between the rigid flat and the sphere is assessed by the Lennard–Jones (LJ) potential, which is applied to the sphere and the rigid flat by a user subroutine. The evolution of the adhesive force with tangential displacement in the full-stick condition is revealed. The results indicate that the increasing effect of adhesive energy on the static friction coefficient gradually diminishes with an increase in the adhesive energy and the external normal load. Finally, based on an extensive parametric study, an empirical dimensionless expression is obtained to predict the static friction coefficient of the spherical adhesive microcontact considering the intermolecular force. [ABSTRACT FROM AUTHOR]

To quantify the influence of absorbed water in PA6 on the pre-treatment and bonding process, an unfilled and unreinforced PA6 material is investigated in a dried and saturated state. The material is pre-treated by atmospheric pressure plasma jet (APPJ) with varying jet distances. The surfaces are investigated by contact angle measurements, DSC and FTIR to detect molecular and morphological changes in the surface. To evaluate the bonding strength, samples are bonded with a two-component polyurethane adhesive and a two-component acrylate adhesive and tested in a lap shear and a tensile configuration. The results show that water content has a significant influence on the effectivity of the pre-treatment process and the resulting bonding strength and failure mechanism. The adhesion is majorly affected, however these effects do not influence the macroscopic wetting behavior and cannot be measured in contact angles. FTIR spectra and DSC scans do not show significant changes in molecular groups or crystallinity that would explain the observed adhesion improvement in dried samples. High bonding strength is only achieved with adherents at low water content. [ABSTRACT FROM AUTHOR]

Drosophila glue, a bioadhesive produced by fly larvae to attach themselves to a substrate for several days, has recently gained attention for its peculiar adhesive and mechanical properties. Although Drosophila glue production was described more than 50 years ago, a general survey of the adhesive and mechanical properties of this proteinaceous gel across Drosophila species is lacking. To measure adhesion, we present here a protocol that is robust to variations in protocol parameters, pupal age and calculation methods. We find that the glue, which covers the entire pupal surface, increases the animal rigidity and plasticity when bound to a glass slide. Our survey of pupal adhesion in 25 Drosophilidae species reveals a wide range of phenotypes, from species that produce no or little glue and adhere little, to species that produce high amounts of glue and adhere strongly. One species, D. hydei, stands out from the rest and emerges as a promising model for the development of future bioadhesives, as it has the highest detachment force per glue area and produces relatively large amounts of glue relative to its size. We also observe that species that invest more in glue tend to live in more windy and less rainy climates, suggesting that differences in pupal adhesion properties across species are shaped by ecological factors. Our present survey provides a basis for future biomimetic studies based on Drosophila glue. [ABSTRACT FROM AUTHOR]

The contact of an elastic quarter- or eighth-space is studied under the condition that the movement of the side surface of the quarter-space is constrained: It can slide freely along the plane of the side surface but its normal movement is blocked (for example, by a rigid wall). The solution of this contact problem can be easily achieved by additionally applying a mirrored load to an elastic half-space. Non-adhesive contact and the Johnson-Kendall-Roberts (JKR)-type adhesive contact between a rigid sphere and an elastic quarter-space under such a boundary condition is numerically simulated using the fast Fourier transform (FFT)-assisted boundary element method (BEM). Contacts of an elastic eighth-space are investigated using the same idea. Depending on the position of the sphere relative to the side edge, different contact behavior is observed. In the case of adhesive contact, the force of adhesion first increases with increasing the distance from the edge of the quarter-space, achieves a maximum, and decreases further to the JKR-value in large distance from the edge. The enhancement of the force of adhesion compared to the half-space-contact is associated with the pinning of the contact area at the edge. We provide the maps of the force of adhesion and their analytical approximations, as well as pressure distributions in the contact plane and inside the quarter-/eighth-space. [ABSTRACT FROM AUTHOR]

Experimental results are presented for the contact acoustic nonlinearity of interfaces between two solid surfaces in dry contact which experience a moderate level of plastic deformation. The current research aims at investigating the effects of the elastoplastic hysteresis, surface roughness, and possible adhesive force on the acoustic nonlinearity. The ultrasonic results are compared with results from the elastoplastic contact model of Kim and Lee (2007) and the clapping model of Blanloeuil et al. (2020), which reveals that the nonlinearities are dominated by clapping of lightly contacting cracks at the interface at low pressures and by the elastoplastic nonlinear spring at high pressures. On top of this major trends, there are consistent minor trends which are attributed to the effects of adhesive force. There is a critical pressure level at which the adhesive clapping of cracks starts being more pronounced. As predicted by the model, the nonlinearity increases with the surface roughness and thus is always lower during unloading in the high pressure regime. The effects of the adhesion are investigated by measuring the nonlinearity at two different relative humidity levels. Some systematic, physically reasonable trends in the experimental results illustrates possible effects of the adhesive force on the acoustic nonlinearity. [ABSTRACT FROM AUTHOR]

Researchers of the Nekrasov Iron & Steel Institute, National Academy of Sciences of Ukraine, conduct studies aimed at developing analytical methods for predicting the strength characteristics of pellets. These studies use analyses of phase interaction mechanisms within free-flowing media to develop theoretical ideas on the formation of strong bonds in the pellets through adhesion. This led to the establishment of local models of adhesion processes for two basic particle interaction schemes: 'particle + particle' and 'particle + liquid phase + particle'. Experimental studies undertaken in laboratory premises of the Nekrasov Iron & Steel Institute for the 'particle + particle' interaction scheme provided the foundation for a method to determine the strength characteristics of pellets made from fine-grained materials with zero moisture at compaction pressures ranging from 50 to 220 MPa. The first part of the paper justified methodological prerequisites for experiments to study strong bonds within the compacts for the 'particle + liquid phase + particle' interaction scheme. The methodological prerequisites accounted for the mechanical, physical, and physicochemical interactions, both between individual particles of the pelletized material and between the charge components (liquid phase). A generalized analysis of the experimental findings allowed evaluating a range of potential adhesion processes for the 'particle + liquid phase + particle' interaction scheme, pinpointing their manifestation, examining their nature, and assessing the effect of a liquid phase introduced into the pelletized charge, considering the compaction pressures applied. This paper focuses on experimental findings for the 'particle + liquid phase + particle' interaction scheme, establishing analytical relationships between the strength characteristics of pellets and integral indicators of the adhesive bond mechanism in this interaction scheme (in particular, relationship between the bulk density (ρ0) and moisture content (Wm) for materials in the first group of systematization). Additionally, an analytical relationship between the compaction factor for compacts produced at a pressure (P) of 220 MPa (Kcomp220), considering their loosening, and the bulk density of materials (ρ0) in the first group of systematization was established for the first time. Analysis of the findings led to a hypothesis suggesting that the amount of the liquid phase (in particular, water) introduced into the material should be balanced by its potential displacement during compaction to achieve maximum compact strength. Based on the hypothesis, a novel equation was derived to calculate the amount of liquid binder (water) to promote the most favorable conditions for the adhesion processes, thereby imparting the maximum strength to compacts from materials in the first group of systematization. A comparative analysis between the experimental findings and calculations confirmed that the equation was accurate. Consequently, an analytical method was proposed to determine the moisture content needed in the charge to produce compacts with maximum strength from materials in the first group of systematization (ρpycn ≥ 4.64 × × 10–3). [ABSTRACT FROM AUTHOR]

The problem of clamping complex or low-stiffness parts in technically and economically advantageous conditions is of interest for many manufacturing companies. An emerging method for this type of parts is fixing with adhesive. This paper proposes a new adhesive fixing method for low-rigidity parts, using adhesive tape. The use of adhesive tape minimizes the vibrations induced by the tool in the workpiece and minimizes chatter. This method, although simple and cheap, has not been considered before. The validation of this fixing method was done after a series of tests to determine the holding capacity and stability of the fixed part during the machining process. Therefore, a fixture was designed and manufactured to determine the tensile and shear load capacity of adhesive tapes. Two types of parts from different materials and shapes were machined to determine the stability of the fixed part during machining. After determining the dimensional, shape, and positional accuracy, the method was found to be valid. The method has a high potential for clamping parts with low rigidity for machining. [ABSTRACT FROM AUTHOR]

The paper addresses the mathematical justification of a model describing steady vibrations for a planar thermoelastic body with an incorporated thin inclusion. The body is composed of three parts: two adherents and an adhesive layer between them, and we begin with a general mathematical formulation of a problem. By means of the modern methods of asymptotic analysis, we rigorously investigate the behavior of solutions as the thickness of the adhesive tends to zero. As a result, we construct the model that corresponds to the limit case. It turned out that the adhesive is reduced to the inclusion, which is thin (of zero thickness) and relatively hard (compared to the rigidity of the surrounding body). Furthermore, we supplement the obtained results with numerical experiments demonstrating the consistency of the theoretical conclusions. [ABSTRACT FROM AUTHOR]

Nowadays, with the increasing demands for quality and precision in microelectronic packaging, the study and prediction of droplet parameters before packaging have become increasingly important. This paper aims to derive a predictive formula for droplet volume dispensing to improve packaging quality, optimize process parameters, reduce resource waste, enhance process control, and enhance product quality and reliability. Based on the needle transfer method for ultra-microdroplet dispensing, a droplet dispensing device that meets packaging requirements is established, and precise control of droplet volume is achieved by changing the factors that affect droplet formation. The droplets obtained from experiments are analyzed using pixel extraction, and a numerical fitting method is employed to establish a droplet volume model. It is found that the pixel method is a practical approach for determining droplet volume, with an average deviation of approximately 1.85%. By conducting droplet dispensing experiments with varying initial distances, the smallest droplet volume achieved is 24.33 pL, and it is concluded that larger initial distances result in smaller droplet volumes and reduced droplet contact area. Based on the droplet dispensing experimental data obtained by varying the initial distance, mathematical predictive models for droplet volume and droplet contact area are derived. The results show that the average difference rate between predicted and actual volumes is 0.51%, and the average difference rate between predicted and actual contact areas is 0.56%. [ABSTRACT FROM AUTHOR]

In this paper, results are reported from a series of laboratory tests conducted on a swelling soil treated with different jute fibers with a twofold objective of reducing their swell characteristics and enhancing their geomechanical properties. The efficacy of passive inclusion of three different jute fibers (i.e., natural, woven, and bitumen coated) in controlling both swell potential and pressure, and improving undrained shear strength and consolidation behavior has been examined. It is observed that the inclusion of jute fibers in the swelling soil expectedly improves both undrained shear strength and CBR value of the treated soil. For instance, the original undrained shear strength improves from 200 kPa to as high as 675 kPa and the original CBR value increases from 3% to a maximum of 7.1%. Similarly, both swell potential and pressure of the treated soil reduced significantly from 4.1% to as low as 1.2% and from 90 kPa to a minimum of 40 kPa, respectively. The improvements in soil properties could be attributed to the reinforcing ability of fibers, which possess a relatively higher tensile strength, in corroboration with the adhesive bond between fibers and soil particles at the micro level. While the former plays an active role in avoiding progression of shear failure, the latter would passively resist the initiation of slip at the soil-fiber interface. Notably, while shear strength of soil generally improves upon addition of jute fibers, inclusion of the bitumen coated fibers has been observed to be more effective than rest. [ABSTRACT FROM AUTHOR]

The stress-strain state that occurs in multilayered structures (for example, beams) significantly depends on the nature of the interaction of their layers. In practice, when calculating such structural elements, an ideal contact of the layers is most often considered, this implies the continuity of displacement vectors and stresses at the contact boundary. Strict elasticity theory solutions in this case inevitably lead to the appearance of infinite tangential stresses on the free surfaces at the angular points of structures at the layer interfaces. In this paper, the problem of the stress-strain state of a multilayered beam is considered in which the interaction of layers is assumed nonideal. For this aim, a layer interaction model with a thin contact layer between the adhesive and adherends is chosen. The equations obtained on the basis of this model allowed us to find non-singular solutions that describe the essentially inhomogeneous stress-strain state in each layer of the beam and at their interfaces. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of the effect of vacuum ion–plasma treatment on the strength of the adhesive joint of the samples of fiberglass VPS-48/7781-14 grade. The results of the study of the contact angle of wetting the surface of fiberglass, the microstructure of the surface and the shear strength of the adhesive joint after ion–plasma treatment in various modes are presented. [ABSTRACT FROM AUTHOR]

Tantalum is widely used in capacitor field in modern times. The tantalum shell of capacitor is usually obtained by deep drawing process, and adhesive wear of the shell is the main hidden danger during its deep drawing process. In this paper, ultrasonic vibration–assisted deep drawing technology is proposed to manufacture tantalum capacitor shell, in order to effectively control the adhesive wear of tantalum capacitor with the assistance of ultrasonic vibration energy. Influence of ultrasonic vibration on deep drawing force and surface forming accuracy of tantalum cup deep drawing is discussed by applying different amplitudes of ultrasonic vibration signals at different time periods. The results reveal that in the amplitude range of 3–7 μm, the amplitude of 5 μm has the best inhibition effect on adhesive wear during the deep drawing of tantalum cup, and the effect is especially obvious in the initial stage of the deep drawing process; the reduction of wearing can reach more than 22% comparing with the results without ultrasonic amplitude. [ABSTRACT FROM AUTHOR]

Two types of Japanese papers containing 100 % (JP1) and 50 % (JP2) kozo fibers were treated with different adhesives: methyl-cellulose, rice starch, hydroxypropyl-cellulose and acrylic copolymer. The Fourier transform infrared spectroscopic (FTIR) analysis confirmed the formation of adhesive layer on the surface of papers. The influence of accelerated ageing procedures of moist heat ageing and UV radiation on sample surfaces was established using FTIR and contact angle measurements. The degradation level of papers was studied measuring the intrinsic viscosity and determining the degree of polymerization. Mechanical properties were determined by tensile tests. The results showed that the polar and dispersive components of the surface energy depend strongly on the surface treatments as well as on conditions of ageing. Analysis of degree of polymerization and tensile strength revealed that treatment with methyl-cellulose, rice starch and hydroxypropyl-cellulose reduced degradation of Japanese papers. [ABSTRACT FROM AUTHOR]

Tribological properties are the significant factors to evaluate the application of polycrystalline cubic boron nitride(PcBN) with hard materials in vacuum conditions. In the current paper, the tribological properties of PcBN and WC-Co cemented carbide (YG8) during the sliding process are carried out under different loads in vacuum by ball-disk friction and wear experiments. The wear tracks of PcBN and wear scars of YG8 were characterized. The results show that the wear mechanisms of PcBN in vacuum are mainly abrasive wear and adhesive wear. Furthermore, furrows are also detected on the surface of YG8 balls due to the plowing of exfoliated cubic boron nitride. As a result, abrasive wear is the failure form of YG8 ball. The average CoF is negatively correlated with the loads. Moreover, the relationship between friction and wear is discussed deeply. The wear rate of YG8 ball is positively correlated with the load. Additionally, the wear rate ratio of PcBN and YG8 indicates that higher loads can promote the wear rate of YG8, but it also leads to the rapid wear of PcBN. The results could provide significant instructions for the regulation and control of the tribological properties of PcBN in the coming outer space exploration activities. [ABSTRACT FROM AUTHOR]

The adoption of lightweight materials in engineering applications has become more popular over recent years, with adhesives replacing traditional joining methods such as bolts and rivets. Adhesion science and related technologies are arising as cleaner options for sustainable production in modern industry, with adhesive-bonded joints increasingly being used as design solutions in complex products and assemblies. However, the use of structural adhesives has several significant drawbacks, most of which are related to environmental impact, linked to the nature of the adhesive substance, as well as product disassembly/disposal deriving from the fact that adhesive joints are usually irreversible. Within this context, the goal of this paper is to study adhesive joints in mechanical assemblies from a life cycle perspective, offering more comprehensive analysis tools and assembly solutions suitable for industries such as automotive, aerospace, and assembly/packaging machinery. A methodological framework for the comprehensive characterization of bonded joints using effective surface activation techniques has been created and tested. The first phase encompasses the production of samples for mechanical testing under static and fatigue loading conditions. The second includes the characterization of inputs/outputs (life cycle inventory—LCI) for life cycle assessment (LCA) of mechanical assemblies employing adhesive joints and innovative surface activation techniques. The final phase provides a set of eco-design actions based on a critical analysis of the obtained results. The outcomes demonstrate how it is possible to achieve optimal adhesive-bonded joint properties under specific working conditions (e.g., static or fatigue loading) while maintaining a low environmental load using novel surface pre-treatments such as laser and plasma technologies. These outcomes are supported by a case-study in which adhesive joints are applied to the mechanical assembly of a bottle gripper for a food packaging machine. The adoption of eco-design rules in adhesive joint applications will help designers in the development of suitable solutions for lightweight applications from a complete life cycle perspective. [ABSTRACT FROM AUTHOR]

The objective was to determine the postoperative hypersensitivity of two-step Total-etch as compared to one-step Universal adhesives followed by composite restorations on 100 patients by applying Total-etch on one tooth and Universal adhesive on another tooth. The bonds and teeth were randomly selected. Postoperative hypersensitivity was recorded by visual analog scale before, immediately after, and 24 h after the restoration using cold stimulus. The Mann–Whitney test was applied for statistical comparison of postoperative hypersensitivity between the two bonds as well as for any significant difference in genders with each bond. No significant difference was found between postoperative hypersensitivity of the two adhesives before (p-value = 0.57), immediately after (p-value = 0.604), and 24 h after (p-value = 0.728) the restoration. Males showed more hypersensitivity with Total-etch as compared to females before (p-value = 0.037), immediately after (p-value = 0.047), and 24 h after the restoration (p-value = 0.022). No significant difference was found between gender and Universal adhesive at all three stages (p-value > 0.05). The results suggest no significant difference in postoperative hypersensitivity between the two materials when good sample size and proper technique were observed along with the removal of bias like different patients having different pain perceptions and multiple operators having different operating skills. Males showed more hypersensitivity to Total-etch. Trial registration number: Australian New Zealand Clinical Trials. Registry number: ACTRN12622001213730. (Retrospectively registered: 09/09/2022). [ABSTRACT FROM AUTHOR]

This paper describes a study of deformation of an ideal elastoplastic adhesive layer of a sample in the form of an elastic double-cantilever beam. The integral values are determined for a number of adhesives with account for all diagonal stress tensor components in the layer. It is shown that the integral value is significantly affected by the plane problem type in the case where an elastic-plastic model of layer deformation is applied. As demonstrated in the study, compressive stresses may be present during normal fracture in the irreversible deformation region of the adhesive in a plane stressed state. [ABSTRACT FROM AUTHOR]

Water-based acrylic pressure-sensitive adhesives (PSA) are a common component of disposable products such as tapes, labels, and packaging. Such adhesives are generated from fossil-derived monomers and additives and persist in the environment due to their low biodegradability. Furthermore, they can interfere with the recycling and remediation of products they interact with, such as plastic and paper products. Although touted as a promising remedy to these issues, adhesive polymers generated using renewable and degradable monomers tend to fall short regarding performance and cost. This study reports on the fungal degradation behaviors of hybrid PSAs copolymerized mainly from traditional acrylics and lactide-based macromonomers. These structures provide high performance at a reasonable cost and represent an alternative approach to addressing environmental concerns. Evaluating the biodegradability of these hybrid PSAs involved solid and liquid cultures using 53 unique fungal species. Nearly 50% (n = 23) of the screened species showed PSA-degrading capacities of varying degrees, including Trametes versicolor and Pestalotiopsis microspora, providing roughly complete (> 96%) polymer removal in liquid cultures. Fungal degradation of cast adhesive films was monitored using evolved CO2 and mass loss and confirmed through scanning electron microscopy and spectral analysis (FTIR). Enzyme assays, namely laccases, lipases, and proteases, showed a high correlation with the observed biodegradation rates, suggesting that hydrolytic and oxidative enzymes were likely factors driving latex degradation. These results demonstrate that the high-performing hybrid formulation is degradable by fungi. While a portion of the studied adhesive was synthesized using petroleum-derived monomers, this could serve as a bridge technology, helping to usher in more sustainable disposable consumer products until a time comes when all components are renewably sourced. [ABSTRACT FROM AUTHOR]

Reducing the amount of industrial crop waste and converting it into high value-added products in a sustainable manner will not only promote the use of biological resources but will also help in reducing the environmental impact. Bast fibers of Kozo (Broussonetia kazinoki) are a raw material of traditional Japanese paper, known as "Washi." However, the wood part of this plant is not used for Washi and is discarded. The aim of this study was to find a new future use for the wood parts of the plant. The first step was to confirm whether the wooden part of Kozo could be converted into cellulose nanofibers (CNFs). CNFs made from bast fiber alone and from bast fiber that included the outer bark were prepared as samples for comparison. Subsequently, the morphological and chemical structures of the raw materials, wood powder, pulp, and CNFs from each sample were analyzed. Consequently, we found that CNFs made from wooden parts have a chemical structure similar to that of the bast fiber, which is the raw material of Washi; however, it is the thinnest CNF of all those investigated. In addition, the CNF solution prepared from wooden parts adjusted to a 0.5-wt% concentration showed the highest viscosity characteristics and also the highest adhesive strength when applied to Japanese paper. These results indicate that waste wood parts have potential applications as chemical-free thickeners, adhesives, and restorative materials. [ABSTRACT FROM AUTHOR]

Adhesive Capsulitis of the shoulder is a painful pathology limiting shoulder movements, commonly known as "Frozen Shoulder". Since this pathology limits movement, it is important to make an early diagnosis. Diagnosing capsulitis relies on clinical assessment, although diagnostic imaging, such as Magnetic Resonance Imaging, can provide predictive or supportive information for specific characteristic signs. However, its diagnosis is not so simple nor so immediate, indeed it remains a difficult topic for many general radiologists and expert musculoskeletal radiologists. This study aims to investigate whether it is possible to use disease signs within a medical image to automatically diagnose Adhesive Capsulitis. To this purpose, we propose an automatic Model Checking-based approach to quickly diagnose the Adhesive Capsulitis taking as input the radiomic feature values from the medical images. Furthermore, we compare the performance achieved by our method with diagnostic results obtained by professional radiologists with different levels of experience. To the best of our knowledge, this is the first method for the automatic diagnosis of Adhesive Capsulitis of the Shoulder. [ABSTRACT FROM AUTHOR]

Stretchable electronic circuits can seamlessly conform to irregular and dynamic surfaces with high integration. However, current stretchable configurations typically have limited stretchability due to the lack of robust connections between soft interconnects and rigid electronics. Here, we printed highly stretchable metal–polymer conductors on thermoplastic elastomers as interconnects. We developed electronic vests with porous surfaces for rigid electronics and introduced polyester hot-melt adhesives to strengthen connections between soft interconnects and rigid electronics. After thermal bonding, the adhesive penetrates the porous surface of electronic vests, creating a mechanical interlock and providing an adhesion force of 8.34 N/cm for the connection (3× higher than conductive adhesives). Thus, rigid electronics of different sizes and different pin counts can form strong connections to soft interconnects, achieving a maximum strain tolerance of ~700% (10× higher than conductive adhesives). We achieved highly integrated ultra-stretchable displays that can withstand stretching up to 220% without dead pixels. [ABSTRACT FROM AUTHOR]

Polystyrene waste was converted into an ecofriendly adhesive using a toluene–acetone solvent system and compared to that of toluene solvent. The bond strengths of the adhesives were determined. The adhesive with the maximum bond strength was tested for pH, water content, flow behavior, the effect of temperature on viscosity, thermogravimetric analysis, and differential scanning calorimetry. The influence of viscosity on the adhesive bond strength was checked. Fourier transform infrared spectroscopy was used to identify the functional groups in the adhesive, and the effect of toluene and acetone solvent mixing on the bond strength of the polystyrene waste adhesive (PSWA) was determined. An increase in polystyrene concentration increased the adhesive viscosity. Temperature changes did not influence the adhesive's pseudo-plasticity but influenced its viscosity, as temperature rise resulted in a viscosity decrease. The toluene–acetone PSWA sample with a viscosity of 615.01 cP provided the best bond strength and a further decrease or increase in viscosity reduced the bond strength. The bond strength of the toluene–acetone adhesive system was significantly lower than that of the toluene system. The toluene–acetone system, on the other hand, is more environmentally friendly than that of toluene, and its maximum bond strength value of 0.637 N/mm2 is within the range of bond strength values for particleboard production. The eco-friendlier adhesive has a pH of 5.76 and a water content of 5.82% which are also within the range for particleboard adhesives. The eco-friendlier PSWA is more thermally stable with a slower thermal decomposition rate than that of the toluene (control) sample. Its pseudoplastic flow behavior is advantageous for adhesive applications. [ABSTRACT FROM AUTHOR]

Ensuring stable integration of diverse soft electronic components for reliable operation under dynamic conditions is crucial. However, integrating soft electronics, comprising various materials like polymers, metals, and hydrogels, poses challenges due to their different mechanical and chemical properties. This study introduces a dried-hydrogel adhesive made of poly(vinyl alcohol) and tannic acid multilayers (d-HAPT), which integrates soft electronic materials through moisture-derived chain entanglement. d-HAPT is a thin (~1 µm) and highly transparent (over 85% transmittance in the visible light region) adhesive, showing robust bonding (up to 3.6 MPa) within a short time (<1 min). d-HAPT demonstrates practical application in wearable devices, including a hydrogel touch panel and strain sensors. Additionally, the potential of d-HAPT for use in implantable electronics is demonstrated through in vivo neuromodulation and electrocardiographic recording experiments while confirming its biocompatibility both in vitro and in vivo. It is expected that d-HAPT will provide a reliable platform for integrating soft electronic applications. [ABSTRACT FROM AUTHOR]

Natural selection can drive organisms to strikingly similar adaptive solutions, but the underlying molecular mechanisms often remain unknown. Several amphibians have independently evolved highly adhesive skin secretions (glues) that support a highly effective antipredator defence mechanism. Here we demonstrate that the glue of the Madagascan tomato frog, Dyscophus guineti, relies on two interacting proteins: a highly derived member of a widespread glycoprotein family and a galectin. Identification of homologous proteins in other amphibians reveals that these proteins attained a function in skin long before glues evolved. Yet, major elevations in their expression, besides structural changes in the glycoprotein (increasing its structural disorder and glycosylation), caused the independent rise of glues in at least two frog lineages. Besides providing a model for the chemical functioning of animal adhesive secretions, our findings highlight how recruiting ancient molecular templates may facilitate the recurrent evolution of functional innovations. Some amphibians defend themselves against predators by producing a highly adhesive skin secretion, effectively preventing their ingestion. This study shows how changes in the structure and expression of two proteins underlay the parallel evolution of these defence glues in different frog lineages. [ABSTRACT FROM AUTHOR]

Rubber–metal parts inside the car require rubber compounds capable of ensuring optimal function and maximum service life without interface delamination. From this perspective, the strength of the bond which is created by the chemical interaction of rubber and metal by an adhesive is decisive for ensuring the functionality of the entire compound. It is dependent not only on the choice of the right adhesive but also on the rubber compound ingredients and their amount. Here, the influence of different types of carbon blacks as well as different curing systems in combination with a commonly used adhesive is described. The durability of the metal–adhesive–rubber bond is characterized by a specially designed shear strength analysis under quasi-static loading, whereas a significant influence of the structure of the carbon black has shown. It has also been observed that the presence of monosulphidic bonds has a positive effect on the shear strength. [ABSTRACT FROM AUTHOR]

Significant progress has been made in wet adhesives for low salinity water, but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions, resulting in adhesion failure. Thus, the design of adhesives for natural seawater represents challenges less resolved. Herein, a cationic polyelectrolyte (PECHIA) containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural seawater. By combining the ion shielding effect with the "cation-dipole" interactions between PECHIA chains, aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater, allowing for underwater adhesion to various substrates in seawater. The instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa, respectively, while the cured adhesive shows ∼739 kPa tensile adhesion in natural seawater. The design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater. [ABSTRACT FROM AUTHOR]

Amongst the major types of archaeal filaments, several have been shown to closely resemble bacterial homologues of the Type IV pili (T4P). Within Sulfolobales, member species encode for three types of T4P, namely the archaellum, the UV-inducible pilus system (Ups) and the archaeal adhesive pilus (Aap). Whereas the archaellum functions primarily in swimming motility, and the Ups in UV-induced cell aggregation and DNA-exchange, the Aap plays an important role in adhesion and twitching motility. Here, we present a cryoEM structure of the Aap of the archaeal model organism Sulfolobus acidocaldarius. We identify the component subunit as AapB and find that while its structure follows the canonical T4P blueprint, it adopts three distinct conformations within the pilus. The tri-conformer Aap structure that we describe challenges our current understanding of pilus structure and sheds new light on the principles of twitching motility. The cells of many archaeal species display surface appendages that closely resemble bacterial Type IV pili (T4P). Here, Gaines et al. present a cryoEM structure of the archaeal adhesive pilus from Sulfolobus acidocaldarius, showing that the structure of the component subunit follows the canonical T4P blueprint but adopts three distinct conformations within the pilus. [ABSTRACT FROM AUTHOR]

Ultra-low temperature resistant adhesive is highly desired yet scarce for material adhesion for the potential usage in Arctic/Antarctic or outer space exploration. Here we develop a solvent-free processed low-temperature tolerant adhesive with excellent adhesion strength and organic solvent stability, wide tolerable temperature range (i.e. −196 to 55 °C), long-lasting adhesion effect (> 60 days, −196 °C) that exceeds the classic commercial hot melt adhesives. Furthermore, combine experimental results with theoretical calculations, the strong interaction energy between polyoxometalate and polymer is the main factor for the low-temperature tolerant adhesive, possessing enhanced cohesion strength, suppressed polymer crystallization and volumetric contraction. Notably, manufacturing at scale can be easily achieved by the facile scale-up solvent-free processing, showing much potential towards practical application in Arctic/Antarctic or planetary exploration. Ultra-low temperature resistant adhesives are desirable for their potential use in polar areas or space exploration. Here, the authors develop a low-temperature tolerant adhesive with high adhesion strength in a wide tolerable temperature range and long-lasting adhesion effect that exceeds the classic commercial hot melt adhesives. [ABSTRACT FROM AUTHOR]

The challenge of 3D-printed polymer coating performance on metallic substrates is using a proper adhesive layer. Thus, the effect of various adhesive layers on the electrochemical properties of polylactic acid (PLA) as bio-coatings was performed in this study. These coatings were fabricated through a fused deposition modeling 3D printer on AM60 magnesium alloys. Electrochemical properties were examined through electrochemical impedance spectroscopy (EIS) and Tafel polarization tests in a simulated body fluid solution during various exposure times. EIS measurements showed an increase in the impedance of all coatings by about 86–98% compared to the magnesium alloy. However, Tafel polarization indicated a reduction of 64–98% in the corrosion rate of PLA coatings. The obtained results showed that the highest impedance was related to a coating that was printed on a cyanoacrylate adhesive layer, and the surface of magnesium was etched in an acidic solution. The lowest impedance at low exposure time was also attributed to the PLA coating when the surface of substrates was polished. This was based on the adsorption of a high amount of water due to the Fourier-transform infrared spectra results. The applied anodizing pre-treatment was not an effective factor for the high exposure time based on the results of degradation in-vitro measurements. [ABSTRACT FROM AUTHOR]

This paper investigated the effect of cavity cleaning methods on the bond strength of adhesive systems to dentin after removing zinc-oxide eugenol (ZOE) temporary material. Coronal parts of 96 extracted third molar teeth were removed, and occlusal access cavities were prepared. After root canal treatment, cavities were filled with ZOE and stored in distilled water for seven days at 37°C. After ZOE was removed, teeth were randomly divided into three groups according to cavity cleaning methods (control, 2% chlorhexidine, and ethanol), and five subgroups (3-step total-etch, 2-step self-etch, 1-step self-etch, universal adhesive, and chlorhexidine containing universal adhesive). After restoration with composite resin, the specimens were sectioned into 1 mm2 surface area beams. A microtensile bond strength (μTBS) test was performed. Failure modes were determined under a stereomicroscope and analyzed with a scanning electron microscope. The highest μTBS was observed in chlorhexidine-containing universal adhesive after applying ethanol for 30 s. Ethanol application for 30 s created cleaner dentin surfaces and could increase the adhesive penetration by removing the ZOE residues better than the control and 2% chlorhexidine application for 30 s. [ABSTRACT FROM AUTHOR]

Melanin-like nanomaterials have emerged in surface biofunctionalization in a material-independent manner due to their versatile adhesion arising from their catechol-rich structures. However, the unique adhesive properties of these materials ironically raise difficulties in their site-specific fabrication. Here, we report a method for site-specific fabrication and patterning of melanin-like pigments, using progressive assembly on an initiator-loaded template (PAINT), different from conventional lithographical methods. In this method, the local progressive assembly could be naturally induced on the given surface pretreated with initiators mediating oxidation of the catecholic precursor, as the intermediates generated from the precursors during the progressive assembly possess sufficient intrinsic underwater adhesion for localization without diffusion into solution. The pigment fabricated by PAINT showed efficient NIR-to-heat conversion properties, which can be useful in biomedical applications such as the disinfection of medical devices and cancer therapies. Melanin-like materials are becoming important for surface biofunctionalization due to versatile adhesion, but are challenging to prepare in a site-specific manner. Here, the authors report a method using progressive assembly on a catalytic template, for site-specific fabrication and patterning of melanin-like pigments. [ABSTRACT FROM AUTHOR]

The aim of this study was to clarify the effect of universal adhesive (UA) viscosity on the bond strength of resin composite to dentin prepared with Er:YAG laser. Four experimental UAs (SI-1, SI-2, SI-3, and SI-4) were developed by adding 1, 2, 3, and 4 wt/% nanosilica to BeautyBond Xtreme (Shofu), respectively. BeautyBond Xtreme was used as a control (SI-0). The viscosities of experimental UAs were measured using a B-type viscometer. After bovine mandibular anterior teeth were ground with #600 emery paper to obtain the flattened dentin surfaces, the dentin surfaces were cut thinly by irradiating the Er:YAG laser. Specimens were prepared using the respective UA and flowable resin composite and subjected to the microtensile bond strength (µTBS) test. The data from viscosity measurement and the μTBS test were statistically analyzed using the Kruskal–Wallis test. The mean values of viscosity significantly differed among the all experimental groups (p < 0.01). The μTBS of SI-1 and SI-2 was significantly higher than that of SI-0, SI-3, and SI-4 (p < 0.001). The μTBS of SI-0 was significantly lower than that of SI-4 (p < 0.001). The viscosities of the experimental universal adhesives significantly affected their bond strength to laser-cut dentin. [ABSTRACT FROM AUTHOR]

The development of analytical methods for predicting the strength characteristics of pellets produced by the compaction of fine-grained materials remains a significant and relevant area. To advance this area, the mechanisms of phase interactions in bulk media were analyzed. The analysis was then used to develop local models of adhesion processes for two basic particle interaction schemes: 'particle + particle' and 'particle + liquid phase + particle'. For each local model, the types, nature, and combination of adhesion processes that occurred simultaneously were theoretically established, and the factors and indicators that determined the occurrence and intensity of adhesive bonding were justified. The experimental studies conducted in the laboratory premises of the Nekrasov Iron and Steel Institute of the National Academy of Sciences of Ukraine were analyzed to evaluate the nature and extent of influence exerted by the selected factors, determining the adhesion processes, on changes in the strength characteristics of compacts. Considering the results obtained and the analytical dependences established for the 'particle + particle' interaction scheme, a method for predicting the strength characteristics of pellets produced from fine-grained materials with zero moisture was developed. This paper justifies the methodological conditions for experiments intended to create strong bonds within the compacts under the 'particle + liquid phase + particle' interaction scheme, taking into account the mechanical, physical, and physicochemical interaction processes between individual particles of the pelletized material and between the charge components (liquid phase). A generalized analysis of the experimental findings was carried out to estimate the range of potential adhesion processes inherent in the 'particle + liquid phase + particle' interaction scheme, identify their manifestation, study the nature of their interaction, and evaluate the effect of introducing the liquid phase into the pelletized charge, considering the applied compaction pressures. The collected array of experimental data will enable a detailed cross-correlation analysis to determine the influence of various factors on the adhesion processes and the formation of strong bonds within the compacts. The analysis will also help establish the dependence of strength characteristics of compacts on integral indicators contributing to the formation of adhesive bonds and describe the dependence by analytical methods. The results will be used to develop a method to determine the moisture content in the charge required to produce compacts with maximum strength from materials that belong to the first of the four groups of systematization. The classification of materials into specific groups of systematization is determined by their pycnometric density. [ABSTRACT FROM AUTHOR]

Archaeological textiles are suitable material for radiocarbon dating as they are mainly made of organic matter, such as plant and/or animal fibres. Radiocarbon dating provides objective age estimates of archaeological finds, based on measurements of the carbon-14 isotope present in the organic matter against an internationally used reference standard. However, the quantity and quality of carbon present in the organic matter of archaeological textiles can be affected either by the conditions under which the find was preserved (such as carbonisation, chemical change of organic matter to carbon, and mineralisation, which is the gradual replacement of organic matter by metal degradation products), or by the application of certain interventive methods of conservation (such as, consolidation and the application of organic adhesives that add foreign organic matter/carbon to the textile). Six case studies of archaeological textiles dated using the carbon-14 method are presented here. Two carbonised textile finds, two which were mineralised (one treated with adhesives in the past), and a final two which come from inhumation burials (similar to the textile previously treated with adhesives). This paper includes a discussion and review of the dating method, focusing on sample selection, sample preparation, and by evaluating the efficiency of the technique on textile finds at various states of preservation. This study shows that efficiency of the technique is highly dependable on the amount of carbon present in the finds, which does not seem to be affected by carbonisation, but is greatly affected by mineralisation and the incorporation of foreign organic matter, like synthetic consolidants. [ABSTRACT FROM AUTHOR]

Perovskite solar cells promise to be part of the future portfolio of photovoltaic technologies, but their instability is slow down their commercialization. Major stability assessments have been recently achieved but reliable accelerated ageing tests on beyond small-area cells are still poor. Here, we report an industrial encapsulation process based on the lamination of highly viscoelastic semi-solid/highly viscous liquid adhesive atop the perovskite solar cells and modules. Our encapsulant reduces the thermomechanical stresses at the encapsulant/rear electrode interface. The addition of thermally conductive two-dimensional hexagonal boron nitride into the polymeric matrix improves the barrier and thermal management properties of the encapsulant. Without any edge sealant, encapsulated devices withstood multifaceted accelerated ageing tests, retaining >80% of their initial efficiency. Our encapsulation is applicable to the most established cell configurations (direct/inverted, mesoscopic/planar), even with temperature-sensitive materials, and extended to semi-transparent cells for building-integrated photovoltaics and Internet of Things systems. The instability of perovskite solar cells hinders their commercialization. Here, authors report an industrially compatible strain-free encapsulation process based on lamination of highly viscoelastic semi-solid/highly viscous liquid encapsulant adhesive to reduce thermomechanical interfacial stress. [ABSTRACT FROM AUTHOR]

Accurately placing very small amounts of electrolyte on tiny micro-supercapacitors (MSCs) arrays in close proximity is a major challenge. This difficulty hinders the development of densely-compact monolithically integrated MSCs (MIMSCs). To overcome this grand challenge, we demonstrate a controllable electrolyte directed assembly strategy for precise isolation of densely-packed MSCs at micron scale, achieving scalable production of MIMSCs with ultrahigh areal number density and output voltage. We fabricate a patterned adhesive surface across MIMSCs, that induce electrolyte directed assembly on 10,000 highly adhesive MSC regions, achieving a 100 µm-scale spatial separation between each electrolyte droplet within seconds. The resultant MIMSCs achieve an areal number density of 210 cells cm−2 and a high areal voltage of 555 V cm−2. Further, cycling the MIMSCs at 190 V over 9000 times manifests no performance degradation. A seamlessly integrated system of ultracompact wirelessly-chargeable MIMSCs is also demonstrated to show its practicality and versatile applicability. A challenge for densely packed micro-supercapacitors (MSCs) is accurate electrolyte placement. Here authors report a surface adhesive-directed electrolyte assembly strategy for precise isolation of densely packed MSCs at micron scale. [ABSTRACT FROM AUTHOR]

In developing an organic light-emitting diode (OLED) panel for a foldable smartphone (specifically, a color filter on encapsulation) aimed at reducing power consumption, the use of a new optically clear adhesive (OCA) that blocks UV light was crucial. However, the incorporation of a UV-blocking agent within the OCA presented a challenge, as it restricted the traditional UV-curing methods commonly used in the manufacturing process. Although a visible-light curing technique for producing UV-blocking OCA was proposed, its slow curing speed posed a barrier to commercialization. Our study introduces a highly efficient photo-initiating system (PIS) for the rapid production of UV-blocking OCAs utilizing visible light. We have carefully selected the photocatalyst (PC) to minimize electron and energy transfer to UV-blocking agents and have chosen co-initiators that allow for faster electron transfer and more rapid PC regeneration compared to previously established amine-based co-initiators. This advancement enabled a tenfold increase in the production speed of UV-blocking OCAs, while maintaining their essential protective, transparent, and flexible properties. When applied to OLED devices, this OCA demonstrated UV protection, suggesting its potential for broader application in the safeguarding of various smart devices. The slow curing speed of UV-based methods to produce UV-blocking optically clear adhesive (OCA) for display panels poses a barrier to commercialization. Here, authors introduce a visible-light driven photo-initiating system for rapid production of OCAs, demonstrating efficient UV-blocking ability. [ABSTRACT FROM AUTHOR]

The aim was to investigate the influence of endodontic irrigation solutions and protocols on the micro-tensile bond strength (μTBS) to dentin using an etch-and-rinse (ER) or self-etch (SE) adhesive approach. Eighty extracted human molars were ground to dentin. After pretreating for 27 min (21 min–3 min–3 min) with five different endodontic irrigation protocols (Group 1: NaOCl–EDTA–NaOCl; Group 2: NaOCl–NaOCl–EDTA; Group 3: NaOCl–NaCl–NaOCl; Group 4: Dual Rinse–Dual Rinse–Dual Rinse; Group 5: NaCl–NaCl–NaCl), an ER (Optibond FL, Kerr) or a SE (Clearfil SE Bond, Kuraray) adhesive system was applied. After light-curing, composite build-ups were made and cut into dentin-composite sticks. μTBS and failure modes were analyzed. Nonparametric statistical analyses (α = 0.05) were performed for comparison of the five groups within each type of adhesive as well as between the two adhesive systems used. The use of an ER instead of a SE adhesive system resulted in significantly higher μTBS for all irrigation protocols except for group 1 (NaOCl–EDTA–NaOCl) and 2 (NaOCl–NaOCl–EDTA). A statistical difference between the five different endodontic irrigation protocols was only found within the SE adhesive group, where group 1 (NaOCl–EDTA–NaOCl) achieved highest values. The use of an ER adhesive system cancels out the effect of the endodontic irrigation solution. The highest μTBS was achieved when using a NaOCl–EDTA–NaOCl-irrigation protocol in combination with Clearfil SE Bond, which shows that the selection of the endodontic irrigation should match the corresponding SE adhesive system. [ABSTRACT FROM AUTHOR]

Chitosan and bio-based epoxy resins have emerged as promising formaldehyde-free replacements for traditional urea–formaldehyde (UF) adhesives in engineered wood products. This study evaluated five chitosan-to-epoxy weight ratios (3:1, 2:1, 1:1, 1:2, 1:3) as adhesives for hot-pressing medium density fiberboards (MDF) using mixed hardwood fibers. Increasing the epoxy ratio reduced viscosity and gel time, facilitating spraying and fast curing. The density of the formulated MDFs increased with higher epoxy ratios, ranging from 679 kg/m3 for the 3:1 ratio to 701 kg/m3 for the 1:3 formulation, meeting the 500–900 kg/m3 density range specified in EN 323. The 1:3 epoxy-rich formulation enhanced modulus of rupture (MOR) to 31 MPa and modulus of elasticity (MOE) to 2392 MPa, exceeding the minimum requirements of 16 MPa and 1500 MPa set out in EN 310 and EN 316, respectively. Dimensional stability peaked at 5% thickness swelling for the 1:3 formulation after 24 h water soaking, fulfilling the < 25% requirement per EN 316. Internal bond strength reached a maximum of 0.98 MPa for the 3:1 chitosan-rich formulation, satisfying the 0.40 MPa minimum per EN 319. One-way ANOVA tests showed the adhesive ratio had a significant effect on mechanical properties and dimensional stability at 95–99% confidence levels. Duncan's multiple range test revealed the 1:3 ratio boards exhibited statistically significant improvements compared to untreated group. Overall, tailoring the ratios achieved well-balanced properties for MOR, MOE, and dimensional stability, demonstrating potential to replace UF resins. [ABSTRACT FROM AUTHOR]

Grinding tools can be manufactured from metal, vitrified, and resin bond materials. In combination with superabrasives like diamond grains, metal-bonded tools are used in a wide range of applications. The main advantages of metal over vitrified and resin bonds are high grain retention forces and high thermal conductivity. This paper investigates the influence of the atmosphere and manufacturing parameters such as sintering temperature on the properties of titanium-bonded grinding layers. Titanium is an active bond material, which can increase the retention of diamond grains in metal-bonded grinding layers. This can lead to higher bond stress and, consequently, decreased wear of grinding tools in use when compared to other commonly used bond materials like bronze. The reason for this is the adhesive bond between titanium and diamond due to the formation of carbides in the interface, whereas bronze can only form a mechanical cohesion with diamond grains. However, when using oxygen-affine metals such as titanium, oxidizing effects could limit the strength of the bond due to insufficient adhesion between Ti-powder particles and the prevention of carbide formation. The purpose of this paper is to show the influence of the sintering atmosphere and temperature on the properties of titanium-bonded diamond grinding layers using the mechanical and thermal characterization of specimens. A higher vacuum (Δpatm = − 75 mbar) reduces the oxidation of titanium particles during sintering, which leads to higher critical bond stress (+ 38% @ Ts = 900 °C) and higher thermal conductivity (+ 3.4% @Ts = 1000 °C, Ta = 25 °C). X-ray diffraction measurements could show the formation of carbides in the cross-section of specimens, which also has a positive effect on the critical bond stress due to an adhesive bond between titanium and diamond. [ABSTRACT FROM AUTHOR]

Introduction and hypothesis: Articles are getting published on the use of tissue adhesive for vesicovaginal fistula. The objective is to carry out a systematic review on their effectiveness and complications. Methods: A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Two reviewers screened abstracts and full-text and extracted data independently. A narrative synthesis was conducted given the heterogeneity of studies. Results: A total of 1032 studies were identified after searching the database, and 14 articles were included in this systematic review. Of the 84 women included, 12 (14.3%) presented failure or recurrence of their fistula tract. The mean time of follow-up was 11.46 months. The average size of the fistula was 1.05 (range 0.1 to 3.9) cm. Most fistulas (81) included were vesicovaginal fistulas. Nine papers reported the usage of fibrin glue in which only three (6.5%) women reported recurrence of the fistula in a delay of 2 weeks to 26 months. The other studies used cyanoacrylate (14 women) and autologous fibrin injection from the patients' blood (31 women). No significant complications were reported. Complications reported were urinary tract infections in 3 women (3.6%), hematuria in 2 women (2.4%), overactive bladder symptoms in 6 women (7.2%) and septic pelvic thrombosis in one woman (1.2%). Conclusions: Tissue adhesive appears to be a promising alternative for management of urogenital fistulas without reported important complications. [ABSTRACT FROM AUTHOR]