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Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present study involves the preparation of continuous carbon fiber samples treated with epoxy-based sizing agent (EP) and vinyl ester resinbased sizing agent (VE), alongside untreated fibers, aiming to explore the influence pattern of interfacial differences caused by these sizing agents on the compressive properties of carbon fiber composites. Surface analysis, including Scanning Electron Microscope (SEM), Atomic Force Microscope (AFM), and X-ray Photoelectron Spectroscopy (XPS), followed by testing the mechanical properties of carbon fibers and the composite materials. Results indicate that, compared to unsized carbon fibers, EP and VE increase the O atom content on the carbon fiber surface by 13.0% and 18.1%, respectively, and enhance the proportion of active C atoms by 11.3% and 20.3%, respectively. The interlaminar shear strength (GB/T) of carbon fibers is improved by 9.3% and 20.0%, respectively. Given the compatibility between the sizing agent and the matrix resin, VE improves the open-hole compressive strength of composites by 6.7% compared to EP. This improvement in interface bonding performance positively impacts the open-hole compressive properties of the composites, though it has limited effect on the 0° compressive and postimpact compressive strengths. Following EP and VE sizing, the 0° compressive strength increases by 11.8% and 13.6%, respectively, with VE only resulting in a marginal 1.6% improvement over EP. The enhancements in both interlaminar shear strength and open-hole compressive strength are attributed to the increased number of active functional groups at the fiber-resin interface, facilitated by sizing agents, which promote stronger chemical bonding and thus improved load transfer between the fibers and the matrix. VE demonstrates superior performance over EP in regulating the interface state of carbon fibers.The presence or absence of a sizing agent has a more significant impact on the compressive properties of carbon fiber composites than the type of sizing agent used. These findings provide valuable insights for optimizing the preparation and enhancing the compressive performance of carbon fiber composite materials. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The long-term periodicity and uncontrollable interface properties during the preparation process for silicon carbide fiber reinforced silicon carbide-based composites (SiCf/SiC CMC) make it difficult to thoroughly investigate their mechanical damage behavior under complex loading conditions. To delve deeper into the influence of the interface strength and toughness on the mechanical response of microscopic representative volume element (RVE) models under complex loading conditions, in this work, based on numerical simulation methods, a microscale representative volume element (RVE) with periodic symmetric boundary conditions for the material is constructed. The phase-field fracture theory and cohesive zone model are coupled to capture the brittle cracking of the matrix and the debonding behavior at the fiber/matrix interface. Simulation analysis is conducted for tensile, compressive, and shear loading as well as combined loading, and the validity of the model is verified based on the Chamis theory. Further investigation is conducted into the mechanical response behavior of the microscale RVE model under complex loading conditions in relation to the interface strength and interface toughness. The results indicate that under uniaxial loading, increasing the interface strength leads to a tighter bond between the fiber and matrix, suppressing crack initiation and propagation, and significantly increasing the material's fracture strength. However, compared to the transverse compressive strength, increasing the interface strength does not continuously enhance the strength under other loading conditions. Meanwhile, under the condition of strong interface strength of 400 MPa, an increase in the interface toughness significantly increases the transverse compressive strength of the material. When it increases from 2 J/m2 to 20 J/m2, the transverse compressive strength increases by 28.49%. Under biaxial combined loading, increasing the interface strength significantly widens the failure envelope space under σ2-τ23 combined loading; with the transition from transverse compressive stress to tensile stress, the transverse shear strength shows a trend of first increasing and then decreasing, and when the ratio of transverse shear displacement to transverse tensile/compressive displacement is −1, it reaches the maximum. This study provides strong numerical support for the investigation of the interface properties and mechanical behavior of SiCf/SiC composites under complex loading conditions, offering important references for engineering design and material performance optimization. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bridges' expansion joints are prone to damage during operation, and repairing them often requires interruption of traffic, the impact of which can be minimized by using fast-hardening and early-strength expansion joint materials. In this study, a fast-hardening polymer cement composite (PCC) was developed using sulfate aluminate cement and ordinary silicate cement as binding agents and polymer powder as admixture. To improve the crack resistance of the material, several types of fibers were added and the effects of different fiber types and admixtures on the crack resistance of the material were compared using SCB tests. The results showed that the best effect of improving the crack resistance of concrete was achieved with a volume fraction of 0.5% of basalt fibers. Then, a test method for the interfacial shear properties of PCC materials and ordinary concrete was established, and the cohesive force model was selected as the interface simulation parameter for finite element analysis and compared with experimental data to verify its feasibility. Finally, based on the previously obtained PCC material parameters, a solid model of the expansion joint anchorage zone was established to study the mechanical properties of the expansion joint anchorage zone with the application of fast-hardening PCC material. This research provides a new way to develop fast-hardening and early-strength expansion joint materials with high crack resistance. [ABSTRACT FROM AUTHOR]

Textile composites have been widely used in various fields because of their excellent mechanical properties. Textile composites have viscoelastic properties, which mainly include matrix and reinforcement materials. The viscoelastic properties of textile composites containing polymers can be measured and evaluated by measuring and analyzing viscoelastic behaviors such as creep and stress relaxation. However, creep is a typical viscoelastic phenomenon, which means that the material will deform after long-term use. Composite materials with poor creep resistance can easily lead to functional failure, which may lead to some catastrophic events. Therefore, studying the creep properties of industrial textile composites is imperative. This paper reviews the creep-fatigue resistance of textile and textile composites under specific stresses. The creep behaviors of textile composites and the mechanism of creep damage are summarized. The current test and analysis methods for measuring the creep properties of composite materials are outlined. Several factors influence creep behaviors during use, including the type of fibre, the type of polymer matrix, the fabric's structure, interfacial bonding between fibers and polymer matrixes, and external factors like load level and environment. Finally, the current problems and application scenarios of textile composites with creep resistance are presented to provide a basis for the development of creep-resistant textile composites with superior performance. [ABSTRACT FROM AUTHOR]

The long-term periodicity and uncontrollable interface properties during the preparation process for silicon carbide fiber reinforced silicon carbide-based composites (SiCf/SiC CMC) make it difficult to thoroughly investigate their mechanical damage behavior under complex loading conditions. To delve deeper into the influence of the interface strength and toughness on the mechanical response of microscopic representative volume element (RVE) models under complex loading conditions, in this work, based on numerical simulation methods, a microscale representative volume element (RVE) with periodic symmetric boundary conditions for the material is constructed. The phase-field fracture theory and cohesive zone model are coupled to capture the brittle cracking of the matrix and the debonding behavior at the fiber/matrix interface. Simulation analysis is conducted for tensile, compressive, and shear loading as well as combined loading, and the validity of the model is verified based on the Chamis theory. Further investigation is conducted into the mechanical response behavior of the microscale RVE model under complex loading conditions in relation to the interface strength and interface toughness. The results indicate that under uniaxial loading, increasing the interface strength leads to a tighter bond between the fiber and matrix, suppressing crack initiation and propagation, and significantly increasing the material’s fracture strength. However, compared to the transverse compressive strength, increasing the interface strength does not continuously enhance the strength under other loading conditions. Meanwhile, under the condition of strong interface strength of 400 MPa, an increase in the interface toughness significantly increases the transverse compressive strength of the material. When it increases from 2 J/m2 to 20 J/m2, the transverse compressive strength increases by 28.49%. Under biaxial combined loading, increasing the interface strength significantly widens the failure envelope space under σ2-τ23 combined loading; with the transition from transverse compressive stress to tensile stress, the transverse shear strength shows a trend of first increasing and then decreasing, and when the ratio of transverse shear displacement to transverse tensile/compressive displacement is −1, it reaches the maximum. This study provides strong numerical support for the investigation of the interface properties and mechanical behavior of SiCf/SiC composites under complex loading conditions, offering important references for engineering design and material performance optimization.

Highlights Carbon nanotubes can be used to enhance interlaminar mechanical performance of polymer composites due to its physicochemical properties. In this article, a novel method for preparing multi‐walled carbon nanotubes/polyether ether ketone (MWCNT/PEEK) thermoplastic composite film is proposed. The microstructure and interfacial bonding performance of chemically modified and unmodified composites films are analyzed by molecular dynamics simulation and experiment. The composite films are used in CF/PEEK laminates. The results show that MWCNT significantly improve the crystallinity of PEEK resin. Compared with the MWCNT/PEEK composites without chemical modification, the MWCNT‐COOH/PEEK‐OH composite film has a denser structure, and the tensile strength and elastic modulus are increased by 94.5% and 15%, respectively. Furthermore, the interlaminar shear strength of the CF/PEEK laminates doped with MWCNT/PEEK and MWCNT‐COOH/PEEK‐OH composite films increased by 8.3% and 12.7%, respectively. The interfacial bonding performance between MWCNT and PEEK is obtained by molecular dynamics simulation. A novel method for preparing BP/PEEK composite film is proposed. MWCNT/PEEK composite films can effectively enhance the interlaminar performance of CF/PEEK high performance thermoplastic composites. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the self-developed steel fiber position device that can accurately control the spatial position of steel fiber, the effects of steel fiber embedded depth, diameter and embedded angle on the pull-out behavior of steel fiber in ultra-high performance fiber reinforced concrete (UHPFRC) were studied. The results indicate that the maximum pull-out force, pull-out work, maximum pull-out stress and strength utilization rate of steel fiber increase with the increase of steel fiber embedded depth. However, the maximum average bond strength decreases with the increase of steel fiber embedded depth. With the increase of steel fiber diameter, the maximum pull-out force, pull-out work and maximum average bond strength of steel fiber increase correspondingly, while the strength utilization rate and maximum pull-out stress of steel fiber decrease. With the increase of steel fiber embedded angle, the maximum pull-out force and pull-out work of steel fiber increase first and then decrease. The maximum pull-out force and pull-out work reach the maximum value at 45° and 30° of embedded angle, respectively. When the embedded angle is 75°, the failure mode of specimen is that the steel fiber is broken. [ABSTRACT FROM AUTHOR]

Cubic Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (c -LLZTO) electrolyte is one of the most promising solid electrolytes. However, it is rather difficult to promote its electrical performance while reducing process parameters. Therefore, Li 4 GeO 4 is applied as the additive in liquid sintering of LLZTO ceramics in this study. The LLZTO@Li 4 GeO 4 /Li 2 O composite electrolyte sintered at 1180 °C for 3 h performs a significantly promoted microstructure and electrical performance, the ionic conductivity of which reaches 5.77 × 10−4 S cm−1 at 25 °C. The Li 4 GeO 4 /Li 2 O eutectic phase contributed prominently, in which the high concentration of Li+ seaming the LLZTO grains tightly. Meanwhile, Li+ conduction in the consecutive conductive pathways constructed by [GeO 4 ] groups among the grains was greatly stimulated. With the modification of the grain boundary, an improved garnet electrolytes/Li anode interface performance is produced. The Li/Au|LLZTO@Li 4 GeO 4 /Li 2 O|Au/Li symmetrical cell is able to cycle stably for more than 500 h at the current density of 0.1 mA cm−2 at room temperature. [ABSTRACT FROM AUTHOR]

The authors summarize several common methods of carbon fiber surface treatment, analyze the sig- nificance and effect of carbon fiber surface sizing, summarize the types of water-based sizing agents for carbon fi- ber sizing, and predict the development direction of carbon fiber surface sizing. It is found that the systematic study of water-based sizing agents for specific resin varieties, as well as the preparation of new water-based sizing a- gents to improve the weavability of carbon fiber bundles or yarns and their sizing properties will be important re- search directions in the future. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although there are lots of researches about the application of FRP composites on the external bonding and reinforcement of timber structures, they are mostly aimed at Carbon FRP, which has a large difference in mechanical properties and inconsistent deformation with timber. Meanwhile, research about the interface between timber and Flax Fiber Reinforced Polymer (FFRP) with similar properties with timber is limited; hence, relevant models have not been established yet. Similar to linear elastic FRP confined timber structure, the failure of FFRP-timber structure interface is a process in which the interfacial stress is gradually transferred from the loaded end to the free end, and the interfacial stress transfer area, that is an effective bond length of the FFRP-timber interface. In order to study the interfacial stress transfer characteristics between FFRP and timber structure, based on the existing CFRP-timber structure interface bonding theory and mechanism, a single lap shear test is used to conduct a systematic study on bonding length and width are studied to optimized the application of FFRP. The bond-slip behavior is studied and fitted to provide theory support for the application of FFRP in the restoration of ancient timber structures.

The shape memory alloy reinforced composites have promising application potential for aerospace, automotive and biomedical engineering, while the interfacial bonding performance between shape memory alloy and polymer matrix is crucial to the improvement on the mechanical properties. The interfacial bonding mechanical properties are not uniform on the interface between shape memory alloy and the polymer matrix due to the existence of internal defects. Based on the cohesive zone model, an innovative finite element model is proposed to simulate the progressive damage behavior of the interfacial debonding between shape memory alloy and polymer matrix. The good agreement between the numerical results and the available experimental results indicates the validation of the proposed model. The progressive damage and connection of different positions of the interface between shape memory alloy and polymer matrix result in the final interfacial debonding behavior. Further, the effects of the shape memory alloy length-diameter ratio and embedded depth on the interface performance between shape memory alloy and polymer matrix are investigated. [ABSTRACT FROM AUTHOR]

Recycling of reclaimed asphalt pavement (RAP) faces significant challenges due to interfacial interaction problems within reclaimed asphalt mixtures (RAM). This review focuses on two critical interfaces within RAM: the interface between fresh and aged asphalt, and the interface between aged asphalt and aggregate. These interfaces exert a profound influence on the performance of RAM, impacting key pavement attributes such as rutting resistance, fatigue life, and moisture damage resistance. Consequently, a comprehensive understanding and enhancement of these interfacial interactions are essential for optimizing RAP utilization and elevating the overall performance of RAM. The review commences with systematic analysis of two pivotal interface properties within RAM. It delves into the definition of these interfaces, elucidates the factors influencing their performance, and meticulously examines the methodologies employed to evaluate their characteristics. Subsequently, the review investigates the impact of rejuvenating agents, including petroleum-based oils, bio-based oils, and chemical modifiers, on enhancing interfacial properties. Additionally, the role of surface treatment techniques, such as chemical treatments and mechanical grinding, in augmenting interfacial adhesion between asphalt and aggregates is discussed. While progress has been made in interfacial study, several challenges persist. Consequently, the review concludes by providing some recommendations for future research endeavors. These recommendations aim to overcome the existing challenges and advance the field of RAM interfacial property enhancement. [ABSTRACT FROM AUTHOR]

Carbon-based MAPbI 3 perovskite solar cells (C-PSCs) have attracted significant attention due to their low cost and stable performance. However, due to inherent structural defects and an energy level mismatch between the perovskite layer and the carbon electrode, C-PSCs still show a poorer power conversion efficiency (PCE) than traditional perovskite solar cells (PSCs). In this study, LaFeO 3 @C nanocomposite particles were successfully synthesized via pyrolysis of La-containing MIL-100(Fe) MOF gel. By introducing these pre-synthesized LaFeO 3 @C bimetallic composite oxide nanoparticles into the carbon electrode, the device featuring a FTO/SnO 2 /CH 3 NH 3 PbI 3 /LaFeO 3 @C/C architecture achieved an impressive maximum PCE of 16.35%, surpassing that of the pristine device by 9.36%. The enhanced optoelectronic performance can be primarily attributed to enhanced interfacial contacts, superior interfacial charge extraction ability, and better electrical conductivity. The LaFeO 3 @C-based device maintained more than 90% of the initial PCE after being stored for 31 days at room temperature and ambient humidity. This study provides a novel strategy for the preparation of efficient and stable C-PSCs from the perspective of spatial structure regulation of bimetallic MOF-based composites. [ABSTRACT FROM AUTHOR]

Bridges’ expansion joints are prone to damage during operation, and repairing them often requires interruption of traffic, the impact of which can be minimized by using fast-hardening and early-strength expansion joint materials. In this study, a fast-hardening polymer cement composite (PCC) was developed using sulfate aluminate cement and ordinary silicate cement as binding agents and polymer powder as admixture. To improve the crack resistance of the material, several types of fibers were added and the effects of different fiber types and admixtures on the crack resistance of the material were compared using SCB tests. The results showed that the best effect of improving the crack resistance of concrete was achieved with a volume fraction of 0.5% of basalt fibers. Then, a test method for the interfacial shear properties of PCC materials and ordinary concrete was established, and the cohesive force model was selected as the interface simulation parameter for finite element analysis and compared with experimental data to verify its feasibility. Finally, based on the previously obtained PCC material parameters, a solid model of the expansion joint anchorage zone was established to study the mechanical properties of the expansion joint anchorage zone with the application of fast-hardening PCC material. This research provides a new way to develop fast-hardening and early-strength expansion joint materials with high crack resistance.

Natural fibers and their composites have attracted much attention due to the growing energy crisis and environmental awareness. In this work, a natural lignocellulosic fiber was extracted from cow dung waste and its potential use as reinforcing material in resin-based polymer composites was evaluated. For this purpose, cow dung fiber-reinforced composites (CDFC) were fabricated, and their mechanical and morphological properties were systematically investigated and compared with corn stalk fiber composites (CSFC) and sisal fiber composites (SFC). The results showed that the addition of cow dung fibers reduced the density of the polymer composites, increased the water absorption, and enhanced the impact strength and shear strength. The highest impact and shear strengths were obtained at 6 wt.% and 9 wt.% of fiber loading, respectively, which increased by 23.8% and 34.6% compared to the composite without the fibers. Further comparisons revealed that at the same fiber addition level, the CDFC exhibited better mechanical properties than the CSFC; notably, the CDFC-3 (adding 3 wt.% of fiber loading) had an impact strength closer to the SFC-3. Furthermore, an SEM analysis suggested that the cow dung fibers exhibited a rough and crinkly surface with more node structures, and presented good interfacial bonding with the composite matrix. This work revealed that cow dung fibers are a promising candidate as reinforcement for resin-based polymer composites, which promotes an alternative application for cow dung waste resources in the automotive components field. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under the combined action of temperature and creep of CFRP (Carbon Fiber Reinforced Polymer) sheet, the interface between CFRP sheet and steel beams which are strengthened with CFRP sheet will produce relative slip. This slip will affect the interface interaction, reduce the bearing capacity and stiffness of members as well as increase the deformation. In this paper, the elastic method is used to introduce the creep effect of CFRP sheet and the temperature effect of steel beam. The calculation formulas of interface slip between CFRP sheet and steel beam, CFRP sheet tension and steel beam deformation under the combined action of temperature and CFRP creep are established. The accuracy of the analytical formula is verified by finite element analysis using the software ABAQUS. The results show that the CFRP sheet tension is smallest at the beam end while largest at the middle of the span. When the stiffness reaches about 3 ka, CFRP sheet tension basically does not change. When the temperature increases by 5 °C, the tensile force of CFRP sheet increases by about 3.7 kN, 1.8 kN and 2.3 kN, respectively. The increase of stiffness under creep has little effect on the change of CFRP sheet tension. The deformation is largest in the middle of the span while smallest at the beam end. Stiffness, temperature (5–25 °C), CFRP thickness and stiffness under creep have little effect on deformation. When the load increases by 5 kN under creep, the deformation increases by about 2.2 × 10−7 mm, 1.8 × 10−6 mm and 9.4 × 10−7 mm, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Tiangong University is the property of Journal of Tianjin Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The primary mode of failure at the interface between brittle engineering materials and fiber-reinforced polymers (FRP) is interface failure, making it essential to analyze the interface performance to ensure effective collaboration between these materials. Traditional experimental-based methods for interface fracture analysis are time-consuming and costly. This study introduces a deep learning model, "StrainNet," which generates strain distribution and bond-slip curves by learning the temporal variation of strain. These curves are used to evaluate the fracture performance of the interface between brittle engineering materials and FRP. To verify its accuracy, prediction models based on LSTM, GRU, and Basic GAN were established, and StrainNet demonstrated favorable performance compared to these models. StrainNet was applied to experimental test cases and FEM cases, producing strain distribution and bond-slip curves with low RMSE and MAPE values, indicating the model's robustness and generalization ability. Consequently, the developed model provides engineers and researchers with a quicker and more convenient method to obtain strain fields and interfacial constitutive laws, thus improving the design of FRP-reinforced structures. [ABSTRACT FROM AUTHOR]

Pectin, a kind of natural polysaccharide, shows the attractive potential as a natural stabilizer for protein emulsion. The aim of this study is to investigate the effect of pectin on the physical stability, rheology, interface, and interaction properties of the fish gelatin (FG) emulsion, as pectin was utilized to improve the stability of FG, fish oil emulsion. During the study, when pH < 6, the FG-pectin emulsion displayed better storage stability and salinity tolerance. Analyzing the result, pectin could avoid phase separation at the freeze-thaw process and prevent the liquid-gel transition of FG emulsions during storage. On the other hand, when pH ≥ 6, the emulsion displayed high viscosity due to the complex flocculation and stratified during long-term storage. Electrostatic interactions, hydrophobic interactions, and hydrogen bonding of the FG-pectin complexes in the emulsion were all reduced. Overall, pectin improved the stability of FG emulsions through electrostatic repulsion, hydrophobic interactions, and steric hindrance.

A class of N-P-Si-containing synergistic flame retardant T-K, the phosphoric triamide (TEDAP, T) modified with epoxy silane coupling agent KH560 (K) on molecular polarity and structure, was successfully synthesized and utilized as sizing agent of carbon fiber (CF) for surface treatment in carbon fiber reinforced epoxy (CF/EP) composites. Time of flight mass spectrometer (TOF-MS) and Fourier transform infrared spectroscopy (FT-IR) results showed the successful synthesis of T-K and different degrees of oligomerization of T. Scanning electron microscope (SEM) and interlaminar shear strength (ILSS) characterized the surface and interface morphology of CF and relevant composites, indicating that the interface performance was preserved under selected T-K structure. Thermogravimetric (TG) and limiting oxygen index (LOI) testing results reflected the delayed decomposition of CF on T−5% from 450 °C to 700 °C, and increased LOI values of composites from 34% to 44%, illustrating the significant enhancement on flame retardancy in composites by the application of T-K. [ABSTRACT FROM AUTHOR]

The original concrete subjected to environmental attack will change the properties of recycled aggregates, thereupon affecting the performance of recycled concrete. However, there is a lack of research that considers such impact. This study aims at providing knowledge on the performance of concrete containing sulfate-eroded recycled aggregates considering the effect of erosion age on workability, water absorption, mechanical, microstructure and interface characteristics. Results show that the incorporation of sulfate-eroded recycled aggregates increases the slump by up to 21.7%, and decreases the water absorption by approximately 9.9% given an erosion age of 126 days. With recycled aggregates under a long-term sulfate attack, the slump decreases and water absorption increases, which is due to the increased porosity of the attached old mortar on the recycled aggregate. Similarly, adding sulfate-eroded recycled aggregates leads to significant changes in compressive, split-tensile and flexural strength of concrete as well, with a sudden change occurring at an erosion age of 126 days. In addition, a large amount of erosion products, i.e., ettringite, remain in the residual mortar of the long-term eroded recycled aggregate, which results in excessive pore filling and causes more defects. Furthermore, it has a negative impact on the interface bond between recycled aggregates and the new mortar by reducing the proportion of C-S-H in the interface hydrates. • Concrete containing sulfate-eroded recycled aggregates is designed. • The effect of aggregate erosion age on concrete performance is evaluated. • Sulfate-eroded recycled aggregate negatively affects hydrates composition at the interface. [ABSTRACT FROM AUTHOR]

When a reservoir is subjected to long-term water and polymer flooding, the formed preferential flow paths are widely distributed in the formation, and the displacing fluid effect is reduced, thus leaving a large amount of remaining oil unexploited. To enhance the oil recovery efficiency after polymer flooding, it is important to provide effective methods to block the preferential flow paths. The statistical data analysis results of 20 wells after polymer flooding in the Daqing oilfield show that the remaining oil and the preferential flow paths are mainly distributed vertically in the sedimentation units named PI2 and PI3, and the physical plugging and traditional adjusting techniques are not effective. Considering the above, an adaptive compound flooding method is put forward, which is based on the idea of "plugging, adjusting, and flooding. Laboratory experiment results show that the enhanced oil recovery (EOR) of the new polymer flooding method is 13.6%, which is 4.9% higher than that of alkaline/surfactant/polymer (ASP) flooding. The polymer consumption of the new method is more than 10% lower than that of conventional polymer flooding. [ABSTRACT FROM AUTHOR]

The epoxy resin was modified by hyperbranched structure of hydroxyl terminated to obtain waterborne epoxy resin for using as the carbon fiber (CF) sizing agent. By mixing method of waterborne epoxy resin and water, the waterborne epoxy sizing agent can be fabricated directly. In the sizing process, free of volatile organic solvents ensure the safety of operators and environment. Moreover, the introduction of tertiary amine group in hyperbranched structure will promote the reaction between epoxy and hydroxyl groups, and thus enhance the bonding strength between CF and epoxy resin. Results showed that the introduction of sizing agent does not sacrifice the CF single fiber tensile strength. The structure of epoxy resin retained in sizing agent is beneficial to the good wettability between CF and epoxy resin according to surface energy results. Interfacial shear strength value increases from 51.75 to 72.34 MPa, and interlaminar shear strength value increases from 80.32 to 90.34 MPa. These mechanical properties show that hyperbranched epoxy resin sizing agent with a large amount of hydroxyl groups can effectively improving the interface adhesion between CF and epoxy resin, showing a broad application prospect in composite materials field. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sterling seal is a commonly used reciprocating seal, in which the PTFE ring of the seal and the surface material of the piston rod play an important role in the reciprocating sealing process. In this paper, a reciprocating sealing test bench was built, four sets of carbon fiber PTFE sealing rings were used to perform reciprocating sealing bench experiments with Cr-coated piston rods and DLC-coated piston rods. After the experiment, the used four sets of seals were taken as experimental samples, and a new, unused carbon fiber PTFE seal was taken as a reference sample. The surface topography, surface wear, and wear surface elements of the test specimens were measured by three-dimensional white light interference surface topography instrument, field emission environment scanning electron microscope, and field emission scanning electron microscope. Through experimental determination, it is found that the coating material is detached to form abrasive grains, which causes the surface of the sealing ring to wear. This paper also proposes optimization suggestions for the processing method of the sealing ring and the selection of the material of the piston rod coating. [ABSTRACT FROM AUTHOR]

Due to the limitation of surface inertness and wettability of carbon fibers (CF), the adhesion between Poly(ether-ether-ketone) (PEEK) resin matrix and CF is poor, which reduces the mechanical properties of CF/PEEK composites. In order to improve the interfacial performance between PEEK matrix and carbon fiber fabric, sulfonated-polyether-sulfone (s-PSF) was coated as a sizing agent on the surface of the carbon fiber to construct CF/PEEK composite interface. On one hand, the formation of hydrogen bonds between s-PSF and activated CF increases the adhesion between s-PSF and fibers. On the other hand, Good compatibility between S-PSF and PEEK, which improves the interface performance between PEEK and CF. The results showed that the mechanical properties and interface properties of CF/PEEK composite prepared by modified CF were improved to some extent. The flexural strength, flexural modulus, impact strength and interlaminar shear strength of the materials were increased by 57.5 %, 16.7 %, 44.2 % and 39.7 %, respectively. By introducing s-PSF as sizing agent into CF/PEEK composite interface, the comprehensive properties of the material were effectively improved. [ABSTRACT FROM AUTHOR]

Hydrogel is a very promising dressing for hemostasis and wound healing due to its good adhesion and long-term moist environment. However, secondary injury caused by tissue adhesion due to homogeneous hydrogel cannot be ignored. The obvious interface existing in Janus hydrogel will weaken its asymmetric function. Here, a hierarchical adhesive polyacrylic acid-polyurushiol water-oil Janus hydrogel (JPs@PAA-PU) without adhesive layer is fabricated by one-pot method in the stabilization of polystyrene@silica-siliver Janus particles (JPs). The morphological structure, mechanical properties, anisotropic chemical composition, and adhesion performance, in vivo, and in vitro hemostatic properties of Janus hydrogel are investigated. Result shows that the obtained Janus hydrogel possesses obvious compartmentalization in microstructure, functional groups, and chemical elements. Janus hydrogel is provided with asymmetric interfacial toughness with top 52.45 ± 2.29 Kpa and bottom 7.04 ± 0.88 Kpa on porcine liver. The adhesion properties of PAA side to tissue, red blood cells and platelets, promoting effect of PU side on coagulation cascade reaction and its physical battier endow Janus hydrogel with shorter hemostatic time and less blood loss than control group. It also exhibits excellent antibacterial effects against Escherichia coli and Staphylococcus aureus (>90%). Janus hydrogel possesses biosafety, providing safety guarantee for clinical applications in the future., (© 2024 Wiley‐VCH GmbH.)

A fibre laser was used to weld sodium calcium vacuum plate glazes with a PbO-TiO2-SiO2-RxOy filler and the influence of laser power and welding speed on the interface characteristics were studied. The results indicated that the elements at the welded interface and the glaze diffused reciprocally, with a certain thickness and continuous layered wetting layer of interface reaction was formed. X-ray diffraction (XRD) analysis confirmed the existence of microstructural phase of PbTiO3, PbO, SiO2 and AlSiO in the interface reaction wetting layer. Using higher laser power or lower welding speed cannot only be to the benefit of reducing the blowhole defects of the melting layer, but also helps to improve the compactness and flatness of the edge sealing structure. [ABSTRACT FROM AUTHOR]

The performance of hybrid metal composite parts strongly depends on the properties of the mechanical interface between the two components as well as on the deformation behavior. A combination of different joining mechanisms (e.g. adhesive bonding, mechanical form-fit) offers enhanced interface performance. This paper shows a novel interface concept based on form-fit elements induced by forming. Compared to other joining methods, the forming induced interface structure provides improved strength as well as energy absorption. Shear tests show an increase of up to 40% in shear strength and up to 78% in fracture energy compared to non-structured adhesive bondings. [ABSTRACT FROM AUTHOR]

Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) electrolytes have attracted tremendous attentions in recent years. In this work, a novel strategy is proposed to simultaneously address their grain boundary problems and the interface issues with Li anode by introducing GeO 2 additive in sintering of LLZTO ceramics. GeO 2 consumes Li 2 O, forming Li 4 (Ge 5 O 12)/Li 2 O eutectic melt phase in grain boundary regions. Li-Ge-O melt contributes primarily in (i) regulating growth and combination of LLZTO grains, (ii) constructing consecutive Li+ conduction pathways within the electrolytes, (iii) promoting Li wettability on ceramic's surface and (iv) suppressing growth of lithium dendrites. Therefore, the ionic conductivity is increased to 6.23 × 10−4 S·cm−1 and the activation energy is reduced to 0.29 eV. The compact bonding without any modification layer is formed between Li and the electrolyte. The Li|LLZTO@Li 4 (Ge 5 O 12)/Li 2 O|Li symmetrical cell cycles stably for over 400 h at the current density of 0.1 mA·cm−2 and 300 h at the current density of 0.2 mA·cm−2. [Display omitted] • GeO 2 additive is introduced in sintering of LLZTO electrolyte. • Microstructure is optimized by GeO 2 regulation on grain boundary migration. • Consecutive Li+ conduction pathways are constructed by Li-Ge-O phase. • Wettability of Li anode on surface of electrolyte is promoted by Li-Ge-O phase. • Stable cycle of Li/electrolyte bonded interface for more than 400 h is achieved. [ABSTRACT FROM AUTHOR]

Sterling seal is a commonly used reciprocating seal, in which the PTFE ring of the seal and the surface material of the piston rod play an important role in the reciprocating sealing process. In this paper, a reciprocating sealing test bench was built, four sets of carbon fiber PTFE sealing rings were used to perform reciprocating sealing bench experiments with Cr-coated piston rods and DLC-coated piston rods. After the experiment, the used four sets of seals were taken as experimental samples, and a new, unused carbon fiber PTFE seal was taken as a reference sample. The surface topography, surface wear, and wear surface elements of the test specimens were measured by three-dimensional white light interference surface topography instrument, field emission environment scanning electron microscope, and field emission scanning electron microscope. Through experimental determination, it is found that the coating material is detached to form abrasive grains, which causes the surface of the sealing ring to wear. This paper also proposes optimization suggestions for the processing method of the sealing ring and the selection of the material of the piston rod coating.

• B@PT and B@DT composite are prepared. • B@PT and B@DT have better reaction and combustion performance than B. • B@PT has a hydrophobic interface layer with low polarity. • B@PT and B@DTB show higher combustion temperature and reactivity in thermite with n-CuO. Boron powder (B) is considered to be the most ideal fuel for fuel-rich rocket propellants due to its high calorific value. However, substances such as B 2 O 3 and H 3 BO 3 on the surface of B powder not only reduce the combustion efficiency of B, but also seriously deteriorate the preparation process of hydroxyl-terminated polybutadiene (HTPB)-based propellants, making it difficult for B powder to be used in fuel-rich rockets propellant. Herein, two weak polarity molecules, 1 H, 1 H, 2 H, 2 H-perfluorodecyltrichlorosilane (denoted as PT) and decyltrichlorosilane (denoted as DT), are proposed to be directly anchored on the surface of B powder by chemical bonding to change the surface of B powder. The textural and chemical properties of the B powder and the surface-activated B powders, as well their reaction and combustion performance under different conditions, were studied in detail using various experimental methods. The results show that B@PT and B@DT activated by 1 H, 1 H, 2 H, 2 H-perfluorodecyltrichlorosilane and decyltrichlorosilane respectively have better reaction and combustion performance than B powder. The perfluorodecyltrichlorosilane on the surface of B@PT can release radicals such as C n F 2n+2 and C n F 2n with strong oxidizing properties during the thermal decomposition process, which can corrode the oxide layer on the surface of B powder and can significantly improve the combustion performance of B powder. This research is expected to enable the large-scale application of B powder in HTPB-based fuel-rich rocket propellants. [ABSTRACT FROM AUTHOR]

• Higher temperature leads to lower shear strength, stiffness and higher relative slip of ECO concrete and steel interface. • ECO concrete is less susceptible to changes in temperature. • Stress transfer zone in ECO concrete can be observed when shear failure occurs. • A temperature-dependent bond-slip constitutive model for steel and ECO concrete composites was proposed. In recent years, ecology conservation optimization (ECO) modified polyurethane concrete is becoming popular in steel deck pavement areas. However, it is reported that the interface performance between steel and ECO concrete suffers a significant degradation caused by diurnal and seasonal thermal cycling. In this paper, the interfacial performance of steel and ECO concrete composites at different temperatures was investigated through four groups of oblique tests at the temperature of −10 °C, 15 °C, 40 °C and 60 °C. The digital image correlation (DIC) technique is used to measure the strain distribution. The results show that the interfacial shear strength and stiffness of the specimens decrease with the growth of temperature, while the ultimate relative slip increases. Based on regression analysis, the formulas for calculating the interfacial shear strength, shear stiffness, and ultimate relative slip of steel and ECO concrete composites at different temperatures were established. A temperature dependent bond-slip constitutive model was proposed then by considering the temperature dependency of model parameters, which shows great accuracy in describing the bond-slip behavior between the steel and ECO concrete. Furthermore, a finite element analysis (FEA) model was established based on cohesive behavior, which agrees well with experimental results. Our research results can provide guidance for engineering applications of ECO concrete. [ABSTRACT FROM AUTHOR]

This research was undertaken to investigate the influence of the sizing components, principally coupling agents and film formers, of glass fiber on the interface of reinforced polyurethane composites. The contents of film-forming agents and coupling agents were, respectively, checked by acetone extraction and heat treatment. The categories and chemical structures of the film-forming agents, which mainly exist in the extracting solutions, were investigated by nuclear magnetic resonance spectroscopy. The coupling agents, which mainly existed on the extracted glass fiber surfaces, were analyzed by X-ray photoelectron spectroscopy. Then, the interfacial adhesion properties between glass fibers of untreated, extracted and heat-treated and polyurethane resin were measured with micro-droplet test. The results show that the interfacial shear strength of the glass fiber-reinforced polyurethane composite mainly depends on the coupling agents, in which the N-containing groups play a dominant role. The film formers also take some effects, in which the hydroxyl groups have the greatest contribution. [ABSTRACT FROM AUTHOR]

• A novel mussel shell-recycled aggregate concrete is investigated. • The reduced aggregate-mortar bond affects the mechanical properties of concrete. • Reinforced concrete with mussel shells shows worse resistance to steel corrosion. • The weak bonding performance of mussel shell/mortar leads to increased porosity. The sustainable management of solid wastes and the development of alternative construction materials are essential issues that have plagued urban green development, especially for some resource-constrained island countries or cities. The efficient resource utilization of solid wastes as the alternative of construction materials during the concrete production might provide a potentially promising solution to meet these challenges. In this study, the effects of the combined utilization of mussel shell aggregate (MSA) and recycled concrete aggregate (RCA) on mechanical, durability and microstructural properties of mussel shell-recycled aggregate concrete (MS-RAC) were investigated. The results show that the increased MSA replacement rate exhibited a more negative influence on the compressive strength and splitting tensile strength of MS-RAC than the increased RCA replacement rate. The combined utilization of MSA and RCA resulted in a lower steel corrosion resistance (i.e. more negative open circuit potential, higher corrosion current density, and higher corrosion rate) during the chloride attacks. These could be attributed to the higher debonding rate of MSA-mortar interface and more complicated ITZs due to the incorporation of MSA and RCA. Furthermore, compared with the RCA, the incorporation of MSA resulted in more macropores and an increased porosity in MS-RAC, thereby significantly weakening the mechanical and durability properties of concrete. [ABSTRACT FROM AUTHOR]

The fiber/matrix interface was reinforced by introducing nanostructure on the fiber surface, which enlarged the interphase area for stress transfer across the interface. To study the relationship between the interphase area and the interface performance, a low-temperature method for varying the dimensions of ZnO nanowires grown on the carbon fiber surface was proposed. The surface area with ZnO nanowires introduced was controlled by the conditions for growth: ultrasonic dispersion time, reaction time and Polyethylene glycol concentration. The effects of that varying ZnO the nanowires dimensions on interface performance was evaluated using wettability test and interfacial shear strength (IFSS). ZnO nanowires affect the liquid-motion on the fiber surface, and a shift to hydrophobicity was observed with decreasing the surface coverage of ZnO nanowires. A nonlinear relationship between IFSS and the ratio of the area of the introduced ZnO nanowires suggested unfavorable wettability impeded resin infiltration into ZnO nanowires. [ABSTRACT FROM AUTHOR]