Organic Adhesives Research Articles

Evaluation of long-term symptoms and recurrence of bowel nodules after resection of deep bowel endometriosis: A retrospective cohort study

Background — Bowel endometriosis nodules (BEN) result from an abnormal growth of endometrial fragments located on intestine causing visceral pain, scars, and organ adhesions. Deep endometriosis operation (DEO) is performed in case of deep infiltrating endometriosis (DIE) as a routine procedure for BEN excision. In this retrospective cohort study, the authors aimed to investigate the long-term symptoms and the recurrence rate of BEN in DIE women. Methods — The cases were pooled into two groups based on presence of surgery of bowel endometriosis (SBE, n=32) and absence of surgery of bowel endometriosis (no-SBE, n=44). Using inclusion and exclusion criteria, we selected 76 DIE women from Arash Women’s Hospital (Tehran, Iran). General patient information and surgery-related data were extracted from medical histories of DIE patients (2018-2021). Two years of postoperative follow-up were part of our study, and endometriosis symptoms, pelvic pain, and BEN recurrence rate were assessed. Data were analyzed using SPSS (v.19), and statistical significance was assumed at p<0.05. Results — No statistically significant (p=0.54) differences were detected between two groups (SBE and no-SBE) regarding pain recurrence. In SBE group, 28.1% of DIE women exhibited BEN recurrence, while this proportion was 9.4% in no-SBE women that had larger size of BEN. Changes in BEN sizes were not significant (p=0.6) as compared with pelvic pain. Conclusion — No significant differences were found between long-term symptoms and recurrence of BEN in women with DIE after SBE and without SBE. Excision of BEN during surgical procedures is not recommended clinically.

Not Another Dual Attention UNet Transformer (NNDA-UNETR): a plug-and-play parallel dual attention block in U-Net with enhanced residual blocks for medical image segmentation.

Medical image segmentation is crucial for clinical diagnostics and treatment planning. Recently, hybrid models often neglect the local modeling capabilities of Transformers for medical image segmentation, despite the complementary nature of local information from both convolutional neural networks (CNNs) and transformers. This limitation is particularly problematic in multi-organ segmentation, where organs are closely adhered, and accurate delineation is essential. This study aims to develop a novel method that leverages the strengths of both CNNs and transformers to address the challenges of segmenting multiple closely adhered organs, improving accuracy and robustness in multi-organ segmentation. In this study, we present the Not Another Dual Attention block (NNDA-block), a versatile, plug-and-play module that seamlessly integrates channel and spatial attention mechanisms. This block can be incorporated at any stage within the Not Another Dual Attention UNet Transformer (NNDA-UNETR) framework. Our novel approach to spatial attention uniquely combines local modeling, significantly reducing detail and texture loss during the up- and down-sampling processes typical in U-shaped architectures. Evaluations on the Beyond the Cranial Vault (BTCV) and Automatic Cardiac Diagnosis Challenge benchmark datasets demonstrate our method's effectiveness in balancing model complexity with accuracy. On the BTCV dataset, our model sets new state-of-the-art benchmarks, achieving a Dice similarity coefficient of 84.13%, normalized surface dice of 86.96%, mean average surface distance of 3.46 mm, and an Hausdorff distance at 95% of 17.76 mm. Moreover, it reduces the parameter count by 34.2% compared to leading contemporary methods, all while maintaining low computational costs [measured in floating point operations per second (FLOPs)]. NNDA-UNETR offers a robust solution for accurate segmentation in multi-organ tasks, particularly where organ adhesion poses challenges. Its lightweight design also makes it well-suited for deployment in real-world medical environments with limited computational resources.

Bio-hydrogel from RGD peptide/chitosan/β-glycerophosphate prevents postoperative wound adhesion

Wound adhesion after any abdominal and gastrointestinal surgery is as high as 90 %, and if the adhesion is severe, it will be fatal. During the operation, various methods are used to avoid the adhesion of organs, such as reducing surgical wound area and using hydrogel products with short gelation time. However, these gels might cause allergy, and the gels are unsuitable for long-lasting recovery processes because the body absorbs them too quickly to avoid sticking. Hence, we developed a long-lasting, temperature-sensitive hydrogel using arginyl-glycyl-aspartic acid to help heal postoperative wounds. The hydrogel formed at 37 °C, degraded in 7 days up to 50 % and provided a practicable anti-adhesion function. As the cell and animal tests indicated, the hydrogel exhibited preferable biocompatibility and was proven to effectively avoid adhesion behavior after abdominal surgery while boosting tissue proliferation; animal experiments have confirmed that hydrogel can effectively avoid adhesion after abdominal surgery and help tissue proliferation. This hydrogel inhibits SMAD, P38, and PI3K pathways by blocking fibrosis cytokines and TGF-β downstream signaling. This TGF-β inhibition promotes histoarchitecture remodeling and reduces cecum tissue fibrosis. Our hydrogel provides a new option for anti-sticking products and can be applied to versatile medical uses in the future.

Evaluation of wood coating performance and volatile organic compounds

The aim of this study was to evaluate the environment-performance relationship of surface coating applications on data obtained by measuring the emission rates of volatile organic compounds in polyurethane and water-based varnishes. For this purpose, polyurethane and water-based varnishes from five different companies were applied to the test samples of Entandrophragma cylindricum (sapele) and Piptadeniastrum africanum (dabema), both widely used in the production of urban furniture. Volatile organic compound, hardness and adhesion strength were measured during application. When evaluated in terms of performance, polyurethane varnishes showed superior hardness, while water-based varnishes demonstrated better adhesion after the UV test. The hardness values of polyurethane varnishes before and after the UV aging test were 15,9 s and 79,403 s, respectively, while forwater-based varnishes were , the values were 114,92 s and 75,406 s. The adhesion values of water-based varnishes were 2,885 MPa and 1,18 MPa before and after the UV aging test, and for polyurethane varnishes 3,13 MPa and 1,05 MPa for. When the environment-oriented results were evaluated, the ; emission values of volatile organic compounds in polyurethane varnish applications were found to be significantly higher than those in in water-based varnishes applications. While the total emission rate of volatile organic compounds detected in polyurethane varnishes was 53,63 mg/Nm3, while only one brand of water-based varnishes showed a measurable emission value, recorded at 0,0057 mg/Nm3. The volatile organic compounds emission values of other water-based varnishes were below the device detection limit (<0,0035 mg/Nm3), and therefore could not be measured.

Nanoscale Structures of Tough Microparticle-Based Films Investigated by Synchrotron X-Ray Scattering and All-Atom Molecular-Dynamics Simulation.

In this study, the nanoscale structures of microparticle-based films are revealed by synchrotron small-angle X-ray scattering (SAXS) and all-atom molecular-dynamics (AA-MD) simulations. The microparticle-based films consisting of the simplest acrylate polymer microparticles are applied as a model because the films are formed without additives and organic solvents and exhibit high toughness properties. The characteristic interfacial thickness (tinter) obtained from the SAXS analysis reflects the mixing degree of polymer chains on the microparticle surface in the film. The cross-linking density of inner microparticles is found to be strongly correlated to not only several properties of individual microparticles, such as swelling ratio and radius of gyration, but also the tinter and toughness of the corresponding films. Therefore, the tinter and toughness values follow a linear relationship because the cross-linking restricts the mixing of polymer chains between their surfaces in the film, which is a unique feature of microparticle-based films. This characteristic also affects their deformation behavior observed by in situ SAXS during tensile testing and their density profiles calculated by AA-MD simulations. This work provides a general strategy for material design to control the physical properties and structures of their films for advanced applications, including volatile organic compound-free sustainable coatings and adhesives.

Development of Starch Nanoparticles as a Green Consolidant for Paper-based Objects: Synthesis and Design

ABSTRACT Starch is one of the oldest adhesives, and has been utilised for a variety of applications, including as a consolidant for artworks and archives, after cooking. Although widely available, cost-effective, and versatile it has limitations such as large particle size, which makes it challenging for the adhesive to penetrate deeply into objects. Attempts to increase the concentration of starch adhesives for enhanced strength often lead to increased viscosity, hindering penetration and causing an undesirable film on the surface. Achieving a workable consistency often leads to reduced adhesive power. An approach to using nanosized starch as a binder for paper and cellulose-based objects is presented. Starch nanoparticles (SNPs) from wheat, rice, maize and waxy maize were successfully synthesised using a ‘top-down’ approach that is facile as well as energy efficient. Size distribution measurements indicate most particles to be less than 50 nm, smaller than the pore size of most historic papers. SNPs could make a better sizing adhesive than traditionally-made starch paste, and they are also a green alternative to a variety of chemically formulated, organic solvent-based adhesives. The compatibility, non-toxicity, and biodegradability of starch remained uncompromised during the modification.

Biocompatible Tough Ionogels with Reversible Supramolecular Adhesion.

Cohesive and interfacial adhesion energies are difficult to balance to obtain reversible adhesives with both high mechanical strength and high adhesion strength, although various methods have been extensively investigated. Here, a biocompatible citric acid/L-(-)-carnitine (CAC)-based ionic liquid was developed as a solvent to prepare tough and high adhesion strength ionogels for reversible engineered and biological adhesives. The prepared ionogels exhibited good mechanical properties, including tensile strength (14.4 MPa), Young's modulus (48.1 MPa), toughness (115.2 MJ m-3), and high adhesion strength on the glass substrate (24.4 MPa). Furthermore, the ionogels can form mechanically matched tough adhesion at the interface of wet biological tissues (interfacial toughness about 191 J m-2) and can be detached by saline solution on demand, thus extending potential applications in various clinical scenarios such as wound adhesion and nondestructive transfer of organs.

Experimental investigation on the post-fire mechanical properties and charring rate of inorganic-bonded bamboo composite exposed to fire

The fire resistance remains a challenging topic for engineered wood and bamboo structures due to the combustibility of wood and bamboo and the usage of organic adhesives, which are temperature-sensitive substance in fire. As an alternative solution, this paper investigated a novel bamboo-based composite prepared with magnesium oxysulfide inorganic adhesive (inorganic-bonded bamboo composite, InorgBam), and the fire tests were carried out to investigate the post-fire mechanical properties and charring behavior of InorgBam. The reduction effect of fire exposure on compressive or tensile strength parallel-to-grain was experimentally studied. The effects of fire exposure surface numbers, grain direction, geometric dimension and exposure time on charring rate were discussed. Results showed that the InorgBam can be maintained the post-fire strength under compressive or tensile loads parallel to grain without significant degradation when the exposure temperature below 250 °C. The temperature of the char front was determined to be approximate 350°C by using an interpolation method. The charring rate was mainly dominated by the exposure time and decreases nonlinearly with the increase of exposure time, and the charring rate with multi-sided fire exposure was approximately 1.1 times of that exposed to one-sided fire. Finally, a nonlinear model was proposed to predict the charring rate of InorgBam material, which provides a basic reference for understanding the fire resistance of InorgBam material exposed to fire.

High temperature-resistance modification of the magnesium phosphate inorganic adhesive and its bond properties between CFRP sheets and concrete

The carbon fibre reinforced polymer (CFRP)-strengthened concrete structures are faced with the great threat of fire due to the vulnerability of the epoxy organic adhesive to high temperature. The traditional epoxy organic adhesives are thus urgently needed to be replaced by the alternatives with high-temperature resistance. This paper explored the feasibility of using magnesium phosphate inorganic adhesive (MPIA) to serve as the bonding material for the CFRP-strengthened concrete structures. To this end, the high-temperature resistance modification of MPIA was conducted through the addition of glass powder (GP) in this study. The effects of the GP content ranging from 0% to 15% on the temperature development, mechanical property degradation, phase evolution and microstructural characteristics of the MPIA after exposure to different temperatures were investigated. The results showed that the glass powder could effectively fill the pores caused by the decomposition of the hydration products and the cracks caused by the shrinkage of MPIA matrix at elevated temperatures, which improved the microstructure of MPIA significantly and thus alleviated its strength degradation under high temperature. In terms of the mechanical properties, the MPIA with 10% GP (hereinafter referred to as TRMPIA) yielded the best high-temperature resistance. In addition, the interfacial bond property test after high temperature was also conducted on the concrete members strengthened with the CFRP sheets pasted by TRMPIA, and the test results were also compared with the specimens with epoxy served as the bonding material. The results showed that even after exposure to 600°C, the in-plane shear strength of TRMPIA still remained 14.0% of that at room temperature, while the bond strength of epoxy had been completely lost, which highlighted the advantage of high-temperature resistance of the modified MPIA served as the bonding material of CFRP-strengthened concrete structures.

Experimental investigation on duration of load effect of novel inorganic-bonded bamboo composite under flexural load

Conventional engineered wood and bamboo materials commonly require organic adhesives for adequate bonding. As an alternative solution in bio-based composites, a novel bamboo-based composite prepared with a magnesium-based inorganic adhesive was proposed herein, which is named as “inorganic-bonded bamboo composite” and abbreviated as InorgBam. This study investigates the duration of load (DOL) effect on InorgBam beams under long-term flexural load. The percentile matching method was used to obtain the short-term strengths matched to the long-term specimens, and the strength reduction of the long-term specimens was obtained. The DOL result were calibrated using the DOL empirical formulas and DOL damage models, including Gerhards, Foschi and Yao, and Nielsen models. The impact of the selected cumulative probability functions of short-term strength on the DOL analysis has also been discussed. Results illustrated that the strength reduction in the InorgBam was less than the prediction of Madison curve. The value of DOL coefficient determined with Foschi and Yao model was closest to that derived from the empirical fitted formula. The DOL effect of the InorgBam beams was significantly smaller than that of conventional engineered wood beams, which is beneficial for determining the design strength value of InorgBam material.

Nanoscale profiling of the relationship between in-situ organic matter roughness, adhesion, and wettability under ScCO2 based on contact mechanics

Understanding the interface and wetting phenomenon between CO2 and shale in the reservoir environment plays a key role in realizing efficient shale gas development and long-term stable carbon sequestration in the formation. However, previous studies on the interaction between CO2 and reservoir rocks focused on macro-scale and batch experiments of inorganic minerals, and the mechanism at the nanoscale, especially the micro-wetting behavior of the organic interface, remains unclear and needs to be investigated urgently. In this paper, based on the atomic force microscopy (AFM) tapping mode and the AM-FM viscoelastic mapping mode, the in-situ organic matter (OM) morphology and the change of the relationship between the adhesion force and the interfacial wettability under carbon dioxide immersion are investigated, respectively, and the carbon dioxide wettability behavior at the organic interfaces is deeply revealed in the nanoscale. Among them, the contact angle is obtained by the adhesion work combined with the Johnson-Kendall-Roberts (JKR) adhesive contact theory. The results show that the surface roughness of the OM keeps increasing with the ScCO2 immersion time, while the surface adhesion keeps decreasing at the same time. Although the contact angle decreases continuously with immersion time, the OM is always hydrophobic, i.e., CO2 wetting. It can be seen that the surface roughness has a negative correlation with the contact angle, which keeps decreasing with decreasing adhesion. This indicates that ScCO2 immersion expands the gas adsorption sites and at the same time reduces the interfacial energy of the OM slightly, which is extremely beneficial for CO2 to enhance shale gas recovery and to implement long-term stable carbon geologic sequestration. Therefore, this study reveals the mechanism of the carbon sequestration process at the organic interface in depth within the nanoscale for the first time, which provides a new perspective to deeply understand the long-term adsorption and capture variation process of OM in deep reservoirs.

Macroencapsulation of sodium chloride by a double layer strategy for high temperature phase change thermal storage over 800 °C

To solve the key problems of high corrosiveness, easy leakage and low thermal conductivity of sodium chloride as phase change material (PCM) for high-temperature heat storage, this study reports a double-shell coating method to prepare centimeter-sized macrocapsules. The capsules are made of powder raw materials with the help of organic adhesives such as polyvinyl pyrrolidone and carboxymethyl cellulose for shape formation, in which the inner expanded graphite (EG) layer and the outer Al2O3 layer are coated on the salt core spheres and finally are sintered formed at high temperatures. The double-shell capsules can prevent salt from leakage because the inner EG layer is repellent to liquid salt, in contrast, the single Al2O3 shell is penetrated by liquid salt due to their wettability. After 100 cyclic tests, the double-shell capsules have good stability and high durability for long-term use. In order to improve the heat storage density of the capsules, the method of isostatically pressing the cores to increase the compactness is studied. At 200 MPa, the capsules in size of 20@2@2 show a high heat storage capacity of 1024.54 J/cm3 and 551.56 J/g from 600 to 900 °C. The double-shell encapsulated salt PCM can be widely used in high-temperature heat storage over 800 °C in solar thermal power plants and industrial waste heat recovery.

Improvement of Warm-Mix Asphalt Concrete Performance with Lignin Obtained from Bioethanol Production from Forest Biomass Waste

This study aims to assess the effect of adding lignin waste, a by-product of bioethanol production from forest biomass, to asphalt concrete to improve its performance. After adjusting the lignin content based on preliminary Marshall tests, 20% of this by-product by mass of bitumen was added to the asphalt concrete blends via the dry method. This lignin content was suitable to the temperature was decreased 40 °C compared to the usual mixing temperature, thus allowing the production of warm-mix asphalt concrete (WMA) without any other additive. Tests on a gyratory compactor assessed the workability of the studied asphalt concrete, allowing us to obtain these findings. Moreover, lignin improved moisture damage and adhesion resistance between the binder film and the aggregate particles’ surface. The behaviour at high temperatures was also enhanced, resulting in better resistance to permanent deformation. These promising laboratory results show us an opportunity to create value for this type of by-product in substituting commercial additives for asphalt concrete, such as organic wax or adhesion promoters, to allow the production of warm-mix asphalt concrete with improved properties.

Reduced TiO2 nanotube arrays as environmental catalysts that enable advanced oxidation processes: A mini review

Advanced oxidation processes (AOPs) that utilize heterogeneous catalysts are an engaging and compelling technology for treating emerging contaminants in water and wastewater. Substantial efforts have been devoted to developing cost-effective and environmentally benign materials for application in AOPs. Reduced TiO2 nanotube arrays (r-TNAs) have recently emerged as promising environmental materials for efficiently mitigating persistent organic pollutants (POPs) resistant to conventional biological treatment. r-TNAs possess distinct electrical, optical, and catalytic features, including superior conductivity and solar light absorption due to structural defects involving oxygen vacancies and Ti3+ states. Moreover, their well-organized open channel structures provide a substantial surface area, facilitating the efficient mass transfer of reactants and products. Notably, r-TNAs can be grown directly on the substrate without using organic adhesives or binders, which improves their mechanical and chemical durability and facilitates their repeated use. This article represents the pioneering comprehensive review of r-TNAs in AOP applications. We introduce an electrochemical anodization technique to fabricate TNAs and summarizes the reduction methods employed in r-TNA synthesis. We also elucidate the appealing attributes of r-TNAs and explore their applications in emerging AOPs, including persulfate activation, electrocatalysis, and photo(electro)catalysis. Finally, we outline critical challenges and provide insights into future prospects for the development of AOP systems based on r-TNAs.

Experimental investigation into mechanical performance of novel inorganic-bonded bamboo composite columns under axial compression

Engineering wood and bamboo composites bonded by organic adhesives have gradually become an important component in studies of green and sustainable development in the field of civil engineering. As an alternative solution, studies on inorganic adhesives in bio-based composites have sparked widespread research interest. Herein, a novel bamboo-based composite prepared with an inorganic adhesive was proposed, which is named “inorganic-bonded bamboo composite” and abbreviated as InorgBam. The compressive mechanical property is experimentally investigated. Fifteen groups of columns with various slenderness ratios are tested to evaluate the load–bearing capacity and buckling behavior under axial compressive load. The load–lateral deflection curves and stress–strain curves of the InorgBam columns correlated to the slenderness ratios were obtained. Results show that the strength failure with crushing at the end and buckling failure are the two typical failure modes of the InorgBam column under axial compression. The Euler formula and Newlin–Gahagan approach are adopted for calculating the ultimate stress in cases involving strength failure and buckling failure, and the stability coefficient of the InorgBam columns is analyzed using the prediction methods in the existing codes for the design of timber structures. The stability coefficient calculated by using formulas in the current codes for timber structures is feasible for InorgBam columns, and a proposed formula for the stability coefficient in the present study can be finely applied to the design of InorgBam columns. This study has valuable reference in promoting the structural application of this bamboo-based biomaterials.

SUBTYPES OF DEEP ENDOMETRIOSIS ACCORDING TO LAPAROSCOPIC REVISION

A detalied description of the various manifestation of deep endometriosis should be reflected in classification #Enzian, which requires clinicians to understand the anatomical polymorphism of the disease. The purpose of the work is to explore the types of anatomical polymorphism of deep endometriosis, frequency and options for their combination to determine the main and rare subtypes of the disease. Materials and research methods. Deep endometriosis in 98% of cases is a polymorphic disease with a combination of peritoneal and ovarian endometriosis, and in 91.3% of women it is accompanied by adhesions of the pelvic organs of varying severity; in 2% of patients, deep endometriosis is an isolated form with severe damage to hollow organs; this requires proper preparation for surgical intervention in such patients with the involvement of a multidisciplinary team. Research results. Conclusions. Analysis of the identified subtypes in the future will form the basis for the development of an algorithm for standardized surgical intervention to improve the results of surgical treatment of deep endometriosis.

A new insight into the design of robust superhydrophobic and fire retardant wood: Breaking the conflicting requirement on adhesives

As a new star of low carbon footprint material, wood with both superhydrophobic robustness and flame retardancy highly boosts its applications in various fields. However, these individual functionalities have conflicting requirements on the interfacial or bulky properties of its surface coating, especially in flammable organic adhesives (such as epoxy resin (EP) and polydimethylsiloxane (PDMS)) and nanoparticle systems. Therefore, breaking the conflicting requirement on adhesives is a crucial and challenging issue for achieving superhydrophobic robustness without impairing flame retardancy. In this work, a structure of three-dimensional (3D) flower-like hydrotalcite (HT) clusters isolated by hierarchical pores was proposed to resolve the conflicting demand. Such kind of structure was fabricated through a one-step thermally-driven method using HT, EP and perfluorooctyl triethoxysilane (PFOES). Benefitting from the release of gaseous ethanol from the inside of wood and its circulation flow among EP and HT during thermally driven process, the HT particles were bonded with small amount of EP and assembled as robust 3D flower-like HT clusters isolated by micro/nano sized pores, rather than embedded in a thick EP coating. This structure significantly reduced the use of flammable EP and increased the loading of flame retardant HT. Therefore, wood with boosting flame retardancy without compromising its own superhydrophobic robustness was achieved (herein named as HT/EP/PFOES wood). Cone calorimetry test showed that the HT/EP/PFOES wood had a 49.33% reduction in the peak of heat release rate (HRR) and a 34.51% reduction of total heat release (THR), which outperformed most of the existing flame retardants and superhydrophobic lignin-cellulosic materials. Meanwhile, its superhydrophobic robustness was not impaired. Together with a facile one-step thermally driven fabrication process, this structure of 3D flower-like HT clusters provided a new insight into fire retardant and robust superhydrophobic wood.

Performance Study of Diamond Powder-Filled Sodium Silicate-Based Thermal Conductive Adhesives.

With the development of miniaturized, highly integrated, and multifunctional electronic devices, the heat flow per unit area has increased dramatically, making heat dissipation a bottleneck in the development of the electronics industry. The purpose of this study is to develop a new inorganic thermal conductive adhesive to overcome the contradiction between the thermal conductivity and mechanical properties of organic thermal conductive adhesives. In this study, an inorganic matrix material, sodium silicate, was used, and diamond powder was modified to become a thermal conductive filler. The influence of the content of diamond powder on the thermal conductive adhesive properties was studied through systematic characterization and testing. In the experiment, diamond powder modified by 3-aminopropyltriethoxysilane coupling agent was selected as the thermal conductive filler and filled into a sodium silicate matrix with a mass fraction of 34% to prepare a series of inorganic thermal conductive adhesives. The thermal conductivity of the diamond powder and its content on the thermal conductivity of the adhesive were studied by testing the thermal conductivity and taking SEM photos. In addition, X-ray diffraction, infrared spectroscopy, and EDS testing were used to analyze the composition of the modified diamond powder surface. Through the study of diamond content, it was found that as the diamond content gradually increases, the adhesive performance of the thermal conductive adhesive first increases and then decreases. The best adhesive performance was achieved when the diamond mass fraction was 60%, with a tensile shear strength of 1.83 MPa. As the diamond content increased, the thermal conductivity of the thermal conductive adhesive first increased and then decreased. The best thermal conductivity was achieved when the diamond mass fraction was 50%, with a thermal conductivity coefficient of 10.32 W/(m·K). The best adhesive performance and thermal conductivity were achieved when the diamond mass fraction was between 50% and 60%. The inorganic thermal conductive adhesive system based on sodium silicate and diamond proposed in this study has outstanding comprehensive performance and is a promising new thermal conductive material that can replace organic thermal conductive adhesives. The results of this study provide new ideas and methods for the development of inorganic thermal conductive adhesives and are expected to promote the application and development of inorganic thermal conductive materials.

Tough Structural Adhesives with Ultra-Resistance to Both High and Cryogenic Temperature.

Structural adhesion at high temperature has been a challenge for organic adhesives, and the commercially available adhesives that can work at a temperature above 150 °C is rather limited. Herein, two novel polymers were designed and synthesized via facile strategy, which involves polymerization between melamine (M) and M-Xylylenediamine (X), as well as copolymerization of MX and urea (U). With well-balanced rigid-flexible structures, the obtained MX and MXU resins were proved to be outstanding structural adhesives at a wide range temperature of -196~200 °C. They provided room-temperature bonding strength of 13~27 MPa for various substrates, steel bonding strength of 17~18 MPa at cryogenic temperature (-196 °C), and 15~17 MPa at 150 °C. Remarkably, high bonding strength of 10~11 MPa was retained even at 200 °C. Such superior performances were attributed to a high content of aromatic units, which leads to high glass transition temperature (Tg) up to ~179 °C, as well as the structural flexibility endowed by the dispersed rotatable methylene linkages.

Development and performance of particleboard from various types of organic waste and adhesives: A review

Environmentally friendly or green building materials are more commonly used in the construction industry and furniture making industry. The knowledge of the environmental risks including the depletion of natural resources, the impact of pesticides, as well as the amplifier and enforcement criteria of good practice have led to an increase in the practice of recycling waste materials, and in particular, the recycling of abandoned trees in particleboard production. From the adhesive aspect, in view of future constraints of formaldehyde use, suitable alternatives to formaldehyde-based adhesive systems would have to be developed and implemented in the wood processing industry. The present review represents a critical appraisal of various organic wastes and adhesives used as raw materials in particleboard development. The core of this review is an assessment of physical and mechanical properties of particleboards based on various types of organic waste and adhesive. Based on these data, we evaluated their potential to identify suitable alternative raw materials having a certain probability to meet the requirements of a large-scale industry sector. Characteristics such as density, thickness swelling, modulus of rupture (MOR) and modulus of elasticity (MOE) are significant in the studies carried out by researchers worldwide. However, they also depend on the types of raw materials, adhesives, parameters and indicators used throughout particleboard production. As an overall conclusion, some organic wastes have the potential to replace wood fibers as raw materials in particleboard production with similar performances. Natural-based adhesives have also shown the potential to substitute formaldehyde-based adhesives in terms of performance. However, toxicological investigations should be performed before a decision can been made to ensure they are safe and add value as replacements for formaldehyde-based adhesives.