Gel Materials Research Articles

A wearable flexible battery using human body temperature differences

Ionic battery materials are widely used in wearable devices, especially ionic gel materials. In the face of a variety of ionic thermoelectric materials, it is a key issue to select the appropriate thermoelectric ones for different artificial heart power supply needs. In this study, it is aimed to establish a database of ionic thermoelectric materials for existing wearable devices, compare the battery performance under different boundary conditions and different materials based on the physical model of the battery, and select the optimal battery material suitable for an artificial heart. 72 kinds of ionic thermoelectric materials were identified through a literature review. The properties of ionic thermoelectric materials were comprehensively considered from the aspects of the Seebeck coefficient, electric conductivity, and power factor. The materials were determined by a thermoelectric figure of merit (ZT). The physical model of the battery was established by Solidworks. The three-dimensional physical field of thermoelectric materials was analyzed by COMSOL, so as to clarify the temperature and potential change characteristics of thermoelectric materials under different boundary conditions and different material types. Finally, the thermoelectric material with the largest electric potential energy was selected. Under a constant temperature boundary condition of 33 ℃ and 5 ℃, the maximum potential produced was 23.21 mV. By changing the materials and keeping other conditions unchanged, it was found that the potential generated by the six ion gel materials is mostly mV.

State of the Art on Waste Glass Powder as Supplementary Cementitious Material

As a new type of high-performance concrete material, glass powder (GP) concrete is beneficial to the environment and concrete performance. However, the specific application method still needs to be studied. This paper introduces the structure theory of glass and the mechanism by which glass powder affects concrete. Through experiments, the effects of glass powder particle size, content, alkali content, and other factors on alkali-silica reaction (ASR) expansion, mechanical properties, and durability of concrete are compared. It is proven that glass powder can be used as a gel material in concrete. The existing problems in the research are summarized, and the latest research perspectives and methods are suggested.

AIE-active dipyridinyltriphenylamine for dual-model visualization of latent fingerprints

The development of highly efficient latent fingerprints technology (LFPs) on different background remains extremely vital for forensic and criminal investigations. In this work, a pure organic molecular sensor (DPTPA1) was designed to image LFP with strong signal-to-noise ratio by optimizing the imaging technology. DPTPA1 exhibits aggregation-induced emission (AIE) properties in both aqueous solution and solid state. Two pyridine moieties and one aldehyde moiety were introduced as the end-capped units. DPTPA1 exhibits the typical solvatochromic effect whose maximum emission wavelengths red-shift from 410 nm to 540 nm with the increasing polarity of solvents. The obvious emission of DPTPA1 in the aqueous solution is observed around 500 nm (φ = 9.6%). Both cyanoacrylate glue fuming (CGF) and powder dusting (PD) methods were used to obtain the fluorescent images of LFP on glass, tinfoil, steel and plastic substrates. Among them, the CGF method can image the clear second level details of LFP on the glass and tinfoil. The PD method using DPTPA1-loaded silica gel material can obtain the high quality LFP images on the curved surface of all four substrates. This work provides a strategy for lowing the cost in the broad fields of LFPs imaging.

Design of a gravity spin-driven adsorption-based desalination device

Based on the adsorption property of porous materials and the gravitational spin principle, an innovative design of an adsorption desalination device based on gravitational spin-driven phase change materials for heat storage and exotherm was developed. The power required for the conversion of the device compartment is provided by the gravity difference, and the position fixation of the heat insulation baffle is controlled by the magnetic clasp. The source of thermal energy required by the device follows the green and low-carbon principle, relying on sunlight to irradiate the selective coating and convert it into thermal energy, and then transfer the absorbed thermal energy to the phase change material for storage, which increases the solar energy utilization rate by about 80%. The use of phase change materials can maintain the temperature inside the hot chamber at about 70 °C, allowing water molecules to desorb from the silica gel material and water vapor to rise to the top conical roof to condense into fresh water and collect to the mezzanine water storage chamber. The cylindrical chamber is divided into two chambers, hot and cold, and the adsorption and desorption work is carried out simultaneously, with heat loss within 3%. The initial position where the heat insulation baffle is located is equipped with a magnetic buckle, which can precisely control the angle of baffle rotation. The daily water production of a single device is 8.02 kg, and the carbon emission saving is 0.1518 kg. This work is of great significance to the field of energy saving and emission reduction, and the whole can realize self-operation without an electric power drive, which is a novel way of desalination, considering the concept of energy saving and emission reduction and the full utilization of renewable energy.

PVA fiber/cement-based interface in silane coupler KH560 reinforced high performance concrete – Experimental and molecular dynamics study

PVA fiber reinforced cementitious composites are becoming more and more popular. Due to the difference in physical and chemical properties of the materials, there is a problem of weak interfacial properties between PVA and cement.In order to solve this problem, this study adopts the means of pretreatment of PVA fibers with silane coupler KH560 (KH560), and the strengthening mechanism of KH560 is systematically investigated by means of multi-scale analysis. From the macroscopic test data, it was found that the flexural strength of PVA fiber concrete at 28 days was enhanced by 16% maximally when the PVA fiber content was 0.9%. A series of microscopic tests (Scanning Electron Microscope-SEM, X-ray Diffraction- XRD, Fourier Transform Infrared Spectrometer-FTIR) characterizing the interfacial properties of the KH560-modified material revealed the reason why the pretreated PVA could be better embedded in the cementitious base. Because the addition of KH560 not only generates more gel material and increases the tightness of the interfacial structure between the fiber and the cementitious base, but also reacts with the cement to produce Si-O-Si chemical bonds.A molecular model of PVA and a gel model of calcium silicate hydrate (C-S-H), the main product of cement, were constructed using the method of molecular dynamics (MD) simulation technique. The interaction between fibers and C-S-H was found to be not only mechanical occlusion, but also unstable hydrogen and ionic bonds between PVA molecules and C-S-H. The Si-O-Si bond is very important. In summary, the strengthening mechanism of KH560 and PVA synergistically on concrete is summarized by the analysis of different scales. It also provides theoretical and experimental support for the application of KH560 and PVA fibers in composite materials.

Inhomogeneous large deformation of magneto-thermal sensitive hydrogel-based composite structures

Magneto-thermal sensitive hydrogels, created by adding magnetic nanoparticles to thermo-sensitive gel matrices, have gained attention due to their remote controlled actuation. In this study, the inhomogeneous large deformation of magneto-thermal sensitive hydrogels-based composite structures under external stimuli has been investigated. First, based on previous theoretical frameworks, we develop a new finite element approach to simulate the swelling process of magneto-thermal sensitive hydrogel by using UMAT subroutine in the commercial finite element software ABAQUS. Our approach provides more versatility in the imposition of initial conditions compared to existing models that use the UHYPER subroutine. Furthermore, the numerical case is presented to verify the model with a qualitative comparison with experiments, demonstrating its capabilities in explaining complex physical phenomena. Our results can provide a deeper insight into the mechanical mechanism of magneto-thermal sensitive hydrogels and have important implications for their potential applications in tissue engineering and other fields.

Development of an Adhesive Gel System for Changing the Structure and Properties of Its Adhesive Joint via Reactions with Amine Molecules after Adhesion.

Adhesive gel systems are attracting increasing interest from researchers to use gel materials for artificial biomaterials and engineering materials. Humans, among other living beings, eat foods, get nutrients from them, and use these nutrients to grow up day by day. The shapes and characteristics of their bodies change depending on the nutrients they get. This research develops an adhesive gel system that the chemical structure of the adhesive joint and their properties can be changed and regulated after adhesion, like the growth of living beings. The adhesive joint, which is constructed using a linear polymer comprising a cyclic trithiocarbonate monomer and acrylamide, developed in this research reacts with amines and forms chemical structures depending on amines. The differences in chemical structures endow the adhesive joint with the characteristics and properties that depend on the reaction of amines with the adhesive joint.

Gels in Microscale Electrophoresis.

Gel matrices are fundamental to electrophoresis analyses of biopolymers in microscale channels. Both capillary gel and microchannel gel electrophoresis systems have produced fundamental advances in the scientific community. These analytical techniques remain as foundational tools in bioanalytical chemistry and are indispensable in the field of biotherapeutics. This review summarizes the current state of gels in microscale channels and provides a brief description of electrophoretic transport in gels. In addition to the discussion of traditional polymers, several nontraditional gels are introduced. Advances in gel matrices highlighted include selective polymers modified to contain added functionality as well as thermally responsive gels formed through self-assembly. This review discusses cutting-edge applications to challenging areas of discovery in DNA, RNA, protein, and glycan analyses. Finally, emerging techniques that result in multifunctional assays for real-time biochemical processing in capillary and three-dimensional channels are identified.

Evaluation of 3D-printed bolus for radiotherapy using megavoltage X-ray beams

A radiotherapy bolus is a tissue-equivalent material placed on the skin to adjust the surface dose of megavoltage X-ray beams used for treatment. In this study, the dosimetric properties of two 3D-printed filament materials, polylactic acid (PLA) and thermoplastic polyether urethane (TPU), used as radiotherapy boluses, were investigated. The dosimetric properties of PLA and TPU were compared with those of several conventional bolus materials and RMI457 Solid Water. Percentage depth-dose (PDD) measurements in the build-up region were performed for all materials using 6 and 10 MV photon treatment beams on Varian linear accelerators. The results showed that the differences in the PDDs of the 3D-printed materials from the RMI457 Solid Water were within 3%, whereas those of the dental wax and SuperFlab gel materials were within 5%. This indicates that PLA and TPU 3D-printed materials are suitable radiotherapy bolus materials.

PH Modulated Formation of Complexes with Various Stoichiometry between Polymer Network and Fe(III) in Thermosensitive Gels Modified with Gallic Acid.

Thermoresponsive gels based on N-isopropylacrylamide functionalized with amino groups were modified with gallic acid, with gallate (3,4,5-trihydroxybenzoic) groups being introduced into the polymer network. We investigated how the properties of these gels were affected at varying pH, by the formation of complexes between the polymer network of the gels and Fe3+ ions (which form stable complexes with gallic acid, exhibiting 1:1, 1:2, or 1:3 stoichiometry, depending on pH). The formation of complexes with varying stoichiometry within the gel was confirmed using UV-Vis spectroscopy, and the influence of such complexes on swelling behavior and volume phase transition temperature were investigated. In the appropriate temperature range, complex stoichiometry was found to strongly affect the swelling state. Changes in the pore structure and mechanical properties of the gel caused by the formation of complexes with varying stoichiometry were investigated using scanning electron microscopy and rheological measurements, respectively. The volume changes exhibited by p(NIPA-5%APMA)-Gal-Fe gel were found to be greatest at close to human body temperature (~38 °C). Modification of thermoresponsive pNIPA gel with gallic acid opens new opportunities for the development of pH- and thermosensitive gel materials.

Characteristics of persulfate gel materials in groundwater remediation: Column and tank experiments investigations

Using persulfate and environment–friendly gel solution as raw materials, persulfate gel sustained–release material (PGSR) and persulfate gelatin gel sustained–release material (G–PGSR) were developed. The main purpose of this study was to evaluate the potential of PGSR and G–PGSR in sustained release, migration and removal performance through column and tank experimental investigations. Results showed that the maximum release rates of PGSR and G–PGSR in water columns were 1.34 and 0.58 mg min−1 and the cumulative release amounts achieved 2950 and 2818 mg within 75 h, representing release efficiencies of 98.3 % and 93.9 %, respectively. In three sand columns, the maximum release rate was 0.32, 0.21, and 0.16 mg min−1 and the cumulative release achieved 473, 426, and 359 mg within 90 h with release efficiencies of 94.7 %, 85.3 %, and 71.7 %, respectively. Release time and rate of PGSR and G–PGSR are constrained by the permeability of porous media. G–PGSR in the sand tank exhibited migration and release characteristic with the slow–release diffusion effect. Lateral diffusion produced higher S2O82− concentration far beyond what was allowed in the tank. The saturated hydraulic conductivity decreased from 4.9 × 10−3, 1.1 × 10−3, and 4.9 × 10−4 cm s−1 to 2.4 × 10−3, 7.4 × 10−4, and 2.1 × 10−4 cm s−1 in columns filled with medium, fine, and silt, respectively. G–PGSR injection did not significantly change the order of magnitude of hydraulic conductivity. 2,4–dinitrotoluene removal performance was affected with the inlet flow rates, which decreased from 92 %, 82 %, and 78 % to 42 %, 28 %, and 8 % during 24 PV at the flow rate of 0.5, 1.5, and 4.5 mL min−1, respectively. Moreover, the removal efficiency was enhanced by G–PGSR with activated carbon as an activator. This study expands our understanding and ability of persulfate gel materials for groundwater remediation and provides a certain research basis for practical applications.

Antimicrobial and Mechanical Properties of Ag@Ti3C2Tx-Modified PVA Composite Hydrogels Enhanced with Quaternary Ammonium Chitosan.

Polyvinyl alcohol (PVA) is a polymeric material with good biocompatibility, excellent hydrophilicity, and a large number of hydroxyl groups. However, due to its insufficient mechanical properties and poor inhibition of bacteria, it has a lack of applications in wound dressings, stent materials, and other fields. In this study, a simple method was used to prepare composite gel materials: Ag@MXene-HACC-PVA hydrogels with a double-network structure were prepared using an acetal reaction. Due to the double cross-linked interaction, the hydrogel has good mechanical properties and is resistant to swelling. The adhesion and bacterial inhibition were enhanced due to the addition of HACC. In addition, the strain sensing properties of this conductive hydrogel were stable, and the GF (specification factor) was 1.7617 at 40-90% strain. Therefore, the dual-network hydrogel with excellent sensing properties, adhesion properties, antibacterial properties, and cytocompatibility has potential applications in biomedical materials, especially as a tissue engineering repair material.

Suberic Acid-Based Supramolecular Metallogels of Ni(II), Zn(II), and Cd(II) for Anti-Pathogenic Activity and Semiconducting Diode Fabrication

The importance of three synthesized metallogels of suberic acid distinctly with nickel, zinc, and cadmium acetate salts has been uncovered. For the creation of these soft materials, N,N'-dimethyl formamide was utilized as a source of the trapped solvent. The synthesized metallogels display intriguing viscoelasticity, and the interpretation of experimental parameters obtained from rheological results advocates the gel behavior. Microstructural analysis combined with energy-dispersive X-ray confirms the occurrence of individual gel-developing constituents as observed in different hierarchical microstructural patterns. Significant variations in microstructural arrangements with diverse extent of supramolecular non-covalent patterns inside gel networks were perceived through field emission scanning electron microscopy, atomic force microscopy, and transmission electron microscopy analyses. Fourier transform infrared and electrospray ionization-mass spectral analyses and powder X-ray diffraction analysis of metallogel samples of different gel-establishing ingredients help to investigate the possible supramolecular interactions dictating the metallogel scaffolds. Thermogravimetric analysis of xerogel samples was collected from the synthesized metallogels to understand the thermal stability. These gel materials were characterized by their potential antibacterial efficiency. The potency of metallogels against selective Gram-positive and Gram-negative bacteria was visualized via a spectrophotometer. Human pathogens like Klebsiella pneumoniae (MTCC 109), Salmonella typhi (MTCC 733), Vibrio parahaemolyticus, Bacillus cereus (MTCC 1272), Lactobacillus fermentum (NCDO 955), and Staphylococcus aureus (MTCC 96) are employed in this study. Apart from the biological significance, our metallogels demonstrate as incredible diode performance of fabricated semiconducting systems, which exhibit a considerable amount of non-linearity demonstrating a non-ohmic conduction mechanism at room temperature in dark conditions. Device fabrication was achieved from these metallogels employing the sandwich model with indium tin oxide-coated glass substrates/metallogel/Al structure.

Application and Research Prospect of Functional Polymer Gels in Oil and Gas Drilling and Development Engineering.

Polymer gel materials are formed by physically crosslinking and chemically crosslinking to form a gel network system with high mechanical properties and reversible performance. Due to their excellent mechanical properties and intelligence, polymer gel materials are widely used in biomedical, tissue engineering, artificial intelligence, firefighting and other fields. Given the current research status of polymer gels at home and abroad and the current application status of oilfield drilling, this paper reviews the mechanism of polymer gels formed by physically crosslinking and chemically crosslinking, summarizes the performance characteristics and the mechanism of action of polymer gels formed by non-covalent bonding, such as hydrophobic bonding, hydrogen bonding, electrostatic and Van der Waals interactions interactions, and covalent bonding such as imine bonding, acylhydrazone bonding and Diels-Alder reaction. The current status and outlook of the application of polymer gels in drilling fluids, fracturing fluids and enhanced oil recovery are also introduced. We expand the application fields of polymer gel materials and promote the development of polymer gel materials in a more intelligent direction.

Menstrual Blood–Derived Mesenchymal Stem Cells Encapsulated in Autologous Platelet-Rich Gel Facilitate Rotator Cuff Healing in a Rabbit Model of Chronic Tears

Background: Successful management of chronic rotator cuff (RC) tears remains a challenge owing to its limited intrinsic healing capacity and unsatisfactory failure rate. Menstrual blood–derived mesenchymal stem cells (MenSCs) have the potential to differentiate into the chondrogenic or osteogenic lineage. Autologous platelet-rich gel (APG), a gel material derived from platelet-rich plasma (PRP), can be applied as a carrier system for cell delivery and also as a releasing system for endogenous growth factors. Purpose: To investigate the effect of human MenSCs encapsulated in APG (MenSCs@APG) on the healing of chronic RC tears in a rabbit model. Study Design: Controlled laboratory study. Methods: After evaluation of the effect of PRP on MenSC proliferation or differentiation, the stem cells were encapsulated in APG for in vivo injection. Supraspinatus tenotomy from the right greater tuberosity was performed on 45 New Zealand White rabbits. After 6 weeks, these rabbits were randomly allocated to 3 supplemental treatments during supraspinatus repair: saline injection (control [CTL] group), APG injection (APG group), and MenSCs@APG injection (MenSCs@APG group). At week 18, these rabbits were sacrificed to harvest the humerus–supraspinatus tendon complexes for micro–computed tomography (CT), histological evaluation, tensile test, and MenSC tracking. Results: In vitro results showed that APG can stimulate MenSC proliferation and enhance chondrogenic or osteogenic differentiation. In vivo results showed that APG can act as a carrier for delivering MenSCs into the healing site, and also as a stimulator for enhancing the in vivo performance of MenSCs. Micro-CT showed that bone volume/total volume and trabecular thickness of the new bone in the MenSCs@APG group presented significantly larger values than those of the APG or CTL group (P < .05 for all). Histologically, compared with the CTL or APG group, significantly more mature fibrocartilage regenerated at the healing site in the MenSCs@APG group. A large number of human nuclei–stained cells were observed in the MenSCs@APG group, presenting a similar appearance to fibrochondrocytes or osteocytes. Biomechanically, the MenSCs@APG group showed significantly higher failure load and stiffness than the APG or CTL group (P < .05 for all). Conclusion: Human MenSCs@APG facilitated RC healing in a rabbit model of chronic tears. Clinical Relevance: Autogenous MenSCs@APG may be a new stem cell–based therapy for augmenting RC healing in the clinic.

Dielectric Study on Supramolecular Gels by Fiber Structure Formation from Low-Molecular-Weight Gelator/Water Mixtures.

There are various types of gel materials used in a wide range of fields, and their gelation mechanisms are extremely diverse. Furthermore, in the case of hydrogels, there exist some difficulties in understanding complicated molecular mechanisms especially with water molecules interacting through hydrogen bonding as solvents. In the present work, the molecular mechanism of the structural formation of fibrous super-molecular gel by the low molecular weight gelator, N-oleyl lactobionamide/water mixture was elucidated using the broadband dielectric spectroscopy (BDS) method. The dynamic behaviors observed for the solute and water molecules indicated hierarchical structure formation processes in various time scales. The relaxation curves obtained at various temperatures in the cooling and heating processes showed relaxation processes respectively reflecting the dynamic behaviors of water molecules in the 10 GHz frequency region, solute molecules interacting with water in MHz region, and ion-reflecting structures of the sample and electrode in kHz region. These relaxation processes, characterized by the relaxation parameters, showed remarkable changes around the sol-gel transition temperature, 37.8 °C, determined by the falling ball method and over the temperature range, around 53 °C. The latter change suggested a structure formation of rod micelles appearing as precursors before cross-linking into the three-dimensional network of the supramolecular gels. These results clearly demonstrate how effective relaxation parameter analysis is for understanding the gelation mechanism in detail.

Nanoparticle-Imprinted Silica Gel for the Size-Selective Capture of Silver Ultrafine Nanoparticles from Water.

A synthetic approach has been developed to prepare silica gel monoliths that embed well separated silver or gold spherical nanoparticles (NP), with diameters of 8, 18 and 115 nm. Fe3+, O2/cysteine and HNO3 were all successfully used to oxidize and remove silver NP from silica, while aqua regia was necessary for gold NP. In all cases, NP-imprinted silica gel materials were obtained, with spherical voids of the same dimensions of the dissolved particles. By grinding the monoliths, we prepared NP-imprinted silica powders that were able to efficiently reuptake silver ultrafine NP (Ag-ufNP, d = 8 nm) from aqueous solutions. Moreover, the NP-imprinted silica powders showed a remarkable size selectivity, based on the best match between NP radius and the curvature radius of the cavities, driven by the optimization of attractive Van der Waals forces between SiO2 and NP. Ag-ufNP are increasingly used in products, goods, medical devices, disinfectants, and their consequent diffusion in the environment is of rising concern. Although limited here to a proof-of-concept level, the materials and methods described in this paper may be an efficient solution for capturing Ag-ufNP from environmental waters and to safely dispose them.

PO-04-072 THERMOCHROMIC HEART PHANTOM TO MODEL RADIOFREQUENCY ABLATION

We have previously developed a conductive hydrogel for use as an intermediate between heart tissue and catheter tips in cardiac ablation, providing a more uniform and precisely shaped lesion with the goal of minimizing the occurrence of steam pops and repeat procedures in arrythmia patients. Characterization of the gel has involved the repeated use of porcine hearts for an approximation of ablation behavior in human models. As this gel will require testing and iterative development to characterize its performance in ablation, a more conservative, safe, and affordable model of the heart is paramount. The heart phantom is to mimic the visible formation of lesions in ventricular myocardial tissue upon contact with a catheter that imparts radiofrequency (RF) energy. To predict lesion formation as mediated with the hydrogel, we seek to produce a heart model with similar thermally conductive properties as myocardial tissue. Various gel materials were prepared and evaluated for similarity to physiological myocardium, visual appeal, and ease of use for multiple trials, among other factors. Each gel was mixed with a thermochromic pigment (transition temperature of 60 C) and placed in a water bath of normal saline at 37 C for at least ten minutes for temperature equilibration. Preliminary tests were conducted with bare catheters alone instead of with hydrogel. An RF generator was set to 30 then 50 Watts, then Thermocool SF non-irrigated catheters were lightly applied to the gel surface in the saline bath for thirty seconds (Fig 1C). Lesions (white) are formed as shown in the figure for tests with silicone and black pigment, the most successful material combination thus far (Fig 1A and 1B). Compared to lesions formed in prior ex vivo experiments with ventricular myocardial tissue, the width and depth of the lesions formed in the gel model varied up to 22% and 76% from the ex vivo values, respectively. A thermochromic phantom heart for lesion characterization is feasible. Further development of this model seeks to better mimic myocardial tissue by selecting or synthesizing a material that matches the heart's experimental thermal conductivity and designing the phantom to contain similar anatomical compartments as in the left ventricular region. Once the phantom material displays lesions approximately equal in size to those formed in heart tissue, it may be used as a substitute for further characterization of the conductive hydrogel.

Preparation and investigation of self-healing gel for mitigating circulation loss

Lost circulation is a common and complex downhole accident in the process of oil and gas drilling. Traditional bridge plugging material has the limitation of poor adaptability to lost formations. Therefore, this study synthesized a new self-healing plugging material to improve the plugging success rate; specifically, the hydrophobic association polymer lauryl methlacrylate-acrylamide-acrylic acid containing Fe3+ was modified via curdlan to form a composite gel with high strength and self-healing properties. The self-healing time, mechanicalness and rheological properties of the self-healing gel were systematically evaluated. The results showed that the modification of curdlan could significantly improve the mechanical properties and rheological strength of self-healing gel, and the chelating structure formed by Fe3+ and carboxyl groups could further enhance the mechanical properties of the self-healing gel. Toughness and storage modulus of the LF0.15C2 selfhealing gel with the introduction of curdlan and Fe3+ could reach 30.2 kJ/m3 and 3,458 Pa, respectively. Compared with conventional gel materials, composite gels with self-healing properties exhibited better pressure-bearing capacity of 2.5 MPa, and could effectively avoid causing plugging at the entrance of the fractures by high-concentration inert material and improve the pressure-bearing capacity. In addition, the plugging mechanism of the self-healing gel modified via curdlan in formation fractures was analysed in detail. The self-healing gel modified via curdlan prepared in this work has application potential as a lost circulation material in the field of oil and gas drilling. Cited as: Wang, R., Wang, C., Long, Y., Sun, J., Liu, L., Wang, J. Preparation and investigation of self-healing gel for mitigating circulation loss. Advances in Geo-Energy Research, 2023, 8(2): 112-125. https://doi.org/10.46690/ager.2023.05.05

Interaction, rheological and physicochemical properties of emulsified asphalt binders with direct coal liquefaction residue based geopolymers

The use of solid waste and low-cost gel materials to replace or reduce the use of ordinary Portl and cement (OPC) in emulsified asphalt (EA) binder has positive significance for the comprehensive energy consumption and economic cost of cold mix asphalt (CMA) pavement. The proposed study investigates the interaction, rheological and physicochemical properties of emulsified asphalt (EA) with direct coal liquefaction residue based geopolymers (DG) by fluorescence microscopy tests, the pH test, asphalt conventional tests, dynamic shear rheological test (DSR), and Fourier transform infrared spectroscopy test (FTIR). The test results show that the reaction between DG mortar and EA particles was faster and more violent than that of OPC mortar, resulting in faster demulsification of EA. The added DG mortar increased the pH of the EA binder. Similar to OPC, DG decreased the penetration and ductility of EA evaporation residues, but increased its softening point. The addition of DG to EA changed the rheological properties of its evaporation residue, including complex modulus (G*) and phase angle (δ). Temperature sweep and frequency sweep test results show that DG was comparable to OPC in efficacy against EA residues, improving rutting resistance at the expense of fatigue performance. Complex modulus coefficient (ΔG∗) and complex viscosity coefficient (Δη∗) indicate that the interaction of EA-DG is stronger than that of EA-OPC. FTIR analysis showed that the interaction between DG and EA is linked as a chemical bond.