Nanocomposite Gel Research Articles

Thermally Bisignate Anion Responsive Supramolecular Gel and In Situ Generation of a Conductive Hybrid-Gel Nanocomposite.

Understanding the structure-function relationship is a significant challenge in designing supramolecular soft materials such as supramolecular gels. To address this challenge, we report on two urea-based dipodal ligands, PY-NAP and PY-CF3, with different terminal substituents influencing their gelation properties. The terminal substituents play a crucial role in the gelation abilities. The gel formed from PY-NAP exhibited notably high thermal stability and displayed a unique "thermally bisignate" behavior. Both ligands contain urea and amide units, allowing them to encapsulate the SO42- anion in their pincer cavities in the solid state. The solid-state anion recognition principle is used to construct a selective anion-responsive supramolecular gel. Additionally, the gel was used to sequester precious metal salts from aqueous solutions, achieving an uptake efficiency of over 90%, followed by in situ reduction to form nanoparticles. This concept was then applied to create a conductive supramolecular hybrid gel nanocomposite with significantly high conductivity, holding significant implications for industrial and environmental applications.

Smart Nanocomposite Hydrogels as Next-Generation Therapeutic and Diagnostic Solutions

Stimuli-responsive nanocomposite gels combine the unique properties of hydrogels with those of nanoparticles, thus avoiding the suboptimal results of single components and creating versatile, multi-functional platforms for therapeutic and diagnostic applications. These hybrid materials are engineered to respond to various internal and external stimuli, such as temperature, pH, light, magnetic fields, and enzymatic activity, allowing precise control over drug release, tissue regeneration, and biosensing. Their responsiveness to environmental cues permits personalized medicine approaches, providing dynamic control over therapeutic interventions and real-time diagnostic capabilities. This review explores recent advances in stimuli-responsive hybrid gels’ synthesis and application, including drug delivery, tissue engineering, and diagnostics. Overall, these platforms have significant clinical potential, and future research is expected to lead to unique solutions to address unmet medical needs.

Molybdenum Disulfide Nanosheet-Based Nanocomposite for the Topical Delivery of Umbelliferone: Evaluation of Anti-inflammatory and Analgesic Potentials.

This study aimed to develop a nanocomposite formulation comprising umbelliferone (UMB) and molybdenum disulfide (MoS2) nanosheets as a carrier, termed as the UMB-MoS2 nanocomposite in gel for topical delivery. MoS2 nanosheets were successfully synthesized via a green-hydrothermal reaction of 10 mg of ammonium molybdate and 10 mg of thiourea in 80 mL of deionized water under predetermined conditions. The UMB-MoS2 nanocomposite was prepared by sonicating UMB and MoS2 nanosheets (each of 1 mg/mL) in dimethylformamide. Scanning electron microscopy revealed crumpled nanosheets with an open-ended structure and a nanocomposite as a layered structure. The X-ray diffraction pattern revealed the amorphous nature of UMB in the UMB-MoS2 nanocomposite. Fourier-transform infrared spectra of the UMB-MoS2 nanocomposite had modified bands of the functional group, which confirmed the formation of the nanocomposite. The size and polydispersity-index (435 nm and 0.415, respectively) of the nanocomposite were within the limit for an efficient topical application. Carbopol 934 (2%) was used to prepare the UMB-MoS2 nanocomposite gel (F1) and UMB-Carbopol gel (F2, for comparative evaluation). The pH, spreadability, and viscosity of F1 were found to be 5.56, 5.89 g·cm/s, and 32.5 Pa-sec, respectively, which were optimal for the topical application of gel-based formulations. In vitro release characteristics of both formulations were deemed to be suitable for topical application, where F1 exhibited a biphasic drug release profile and a superior release rate of 94.8% compared to 43.5% for F2 at 24 h. In the carrageenan-induced rat paw edema model, the animal group treated with F1 demonstrated the lowest increase in paw thickness of 26.6%, which was significantly lower as compared to the F2-treated group (52.9%) and the diclofenac sodium-treated group (32.2%). Similarly, in the tail immersion method, F1 exhibited the highest peak tail withdrawal latency of 10.9 s, significantly greater than F2 (8.9 s) and standard treatment (10 s), indicating the superior analgesic activity of F1. This pioneering work introduces a novel UMB-MoS2 nanocomposite with promising anti-inflammatory and analgesic potentials, paving the way for further research into the biomedical applications of MoS2-based nanocarriers.

Development and Optimization of a Nanocomposite Gel Foam for Inhibiting Coal Spontaneous Combustion

ABSTRACT A nanocomposite gel foam inhibitor was made by grafting tea polyphenol onto sodium polyacrylate through the graft polymerization reaction, which was then combined with graphene oxide and a foaming agent. Response surface analysis was used to optimize the ratio to improve the water absorption of the inhibitor. The microstructure of the inhibitor was studied using X-ray diffraction and Fourier-transform infrared spectroscopy. The anti-spontaneous combustion performance of the nano-composite gel foam was tested through a leakage wind plugging experiment and a thermogravimetric experiment. The results show that the optimal additions of graphene, tea polyphenol, and potassium persulfate were 0.76%, 2.806%, and 0.727% of acrylic acid, respectively. The ultimate pressures of the gel foam before and after fully forming the gel were 0. 26 kPa and 0. 736 kPa, respectively, which satisfies the demand for leakage wind plugging in a coal mine. The critical temperature and dry cracking temperature of the gel foam were 112.4°C and 201.0°C, respectively, and the quality of the oxygen-absorbing and weight-gaining stage were almost unincreased. The gel foam showed good water retention, oxygen barrier, and antioxidant properties and can play a significant role in inhibiting the coal spontaneous combustion.

Nanocomposite Perfluorosulfonic Acid/Montmorillonite-Na+ Polymer Membrane as Gel Electrolyte in Hybrid Supercapacitors.

Solid-state supercapacitors with gel electrolytes have emerged as a promising field for various energy storage applications, including electronic devices, electric vehicles, and mobile phones. In this study, nanocomposite gel membranes were fabricated using the solution casting method with perfluorosulfonic acid (PFSA) ionomer dispersion, both with and without the incorporation of 10 wt.% montmorillonite (MMT). MMT, a natural clay known for its high surface area and layered structure, is expected to enhance the properties of supercapacitor systems. Manganese oxide, selected for its pseudocapacitive behavior in a neutral electrolyte, was synthesized via direct co-precipitation. The materials underwent structural and morphological characterization. For electrochemical evaluation, a two-electrode Swagelok cell was employed, featuring a carbon xerogel negative electrode, a manganese dioxide positive electrode, and a PFSA polymer membrane serving as both the electrolyte and separator. The membrane was immersed in a 1 M Na2SO4 solution before testing. A comprehensive electrochemical analysis of the hybrid cells was conducted and compared with a symmetric carbon/carbon supercapacitor. Cyclic voltammetric curves were recorded, and galvanostatic charge-discharge tests were conducted at various temperatures (20, 40, 60 °C). The hybrid cell with the PFSA/MMT 10 wt.% exhibited the highest specific capacitance and maintained its hybrid profile after prolonged cycling at elevated temperatures, highlighting the potential of the newly developed membrane.

Formulation and Characterization of Ferrogels Based on Agar Gum and Octenyl Succinic Anhydride (OSA) Starch

AbstractPhysicochemical and rheological analyses are carried out on ferrogels based on Agar gum in combination with octenyl succinic anhydride (OSA) starch in the presence of magnetic nanoparticles (MNPs) coated with a stabilizing agent (PNiPAAm). The objective of this work is to prepare nanocapsules of MNPs coated with OSA starch present in a rigid network of Agar to obtain a nanocomposite gel (ferrogel). It is found that the effect of MNPs on the properties of ferrogels has a direct relationship with PNiPAAm/OSA starch interactions. The results obtained show that the ferrogels have stable thermal properties and a high melting point (99.7 °C) for high concentrations of MNPs (0.1%). The rheological properties show that this concentration (0.1%) has a negative effect on the crosslinking of Agar, therefore a drop in viscosity. In addition, it is shown that each pore comprises three populations of MNPs (primary: 3–4 nm, secondary: 6–9 nm, and clusters: ≥12 nm). Moreover, it is found that MNPs are coated with OSA starch. In addition, the prepared materials possess at low concentration of MNPs an interesting stiffness and uniform surface morphology with a minimum of clusters leading to stable systems that can be used as biomaterials in nanomedecine.

Earth-Abundant Kaolinite Nanoplatelet Gel Electrolytes for Solid-State Lithium Metal Batteries.

Lithium-ion batteries are the leading energy storage technology for portable electronics and vehicle electrification. However, demands for enhanced energy density, safety, and scalability necessitate solid-state alternatives to traditional liquid electrolytes. Moreover, the rapidly increasing utilization of lithium-ion batteries further requires that next-generation electrolytes are derived from earth-abundant raw materials in order to minimize supply chain and environmental concerns. Toward these ends, clay-based nanocomposite electrolytes hold significant promise since they utilize earth-abundant materials that possess superlative mechanical, thermal, and electrochemical stability, which suggests their compatibility with energy-dense lithium metal anodes. Despite these advantages, nanocomposite electrolytes rarely employ kaolinite, the most abundant variety of clay, due to strong interlayer interactions that have historically precluded efficient exfoliation of kaolinite. Overcoming this limitation, here we demonstrate a scalable liquid-phase exfoliation process that produces kaolinite nanoplatelets (KNPs) with high gravimetric surface area, thus enabling the formation of mechanically robust nanocomposites. In particular, KNPs are combined with a succinonitrile (SN) liquid electrolyte to form a nanocomposite gel electrolyte with high room-temperature ionic conductivity (1 mS cm-1), stiff storage modulus (>10 MPa), wide electrochemical stability window (4.5 V vs Li/Li+), and excellent thermal stability (>100 °C). The resulting KNP-SN nanocomposite gel electrolyte is shown to be suitable for high-rate rechargeable lithium metal batteries that employ high-voltage LiNi0.8Co0.15Al0.05O2 (NCA) cathodes. While the primary focus here is on solid-state batteries, our strategy for kaolinite liquid-phase exfoliation can serve as a scalable manufacturing platform for a wide variety of other kaolinite-based nanocomposite applications.

Nanocomposite Gels Loaded with Flurbiprofen: Characterization and Skin Permeability Assessment in Different Skin Species.

Nanocomposite gels consist of nanoparticles dispersed in a gel matrix. The main aim of this work was to develop nanocomposite gels for topical delivery of Flurbiprofen (FB) for humans and farm animals. Nanocomposite gels were prepared stemming from nanoparticles (NPs) freeze-dried with two different cryoprotectants, D-(+)-trehalose (NPs-TRE) and polyethylene glycol 3350 (NPs-PEG), sterilized by gamma (γ) irradiation, and gelled with Sepigel® 305. Nanocomposite gels with FB-NPs-TRE and FB-NPs-PEG were physiochemically characterized in terms of appearance, pH, morphological studies, porosity, swelling, degradation, extensibility, and rheological behavior. The drug release profile and kinetics were assessed, as well as, the ex vivo permeation of FB was assessed in human, porcine and bovine skin. In vivo studies in healthy human volunteers were tested without FB to assess the tolerance of the gels with nanoparticles. Physicochemical studies demonstrated the suitability of the gel formulations. The ex vivo skin permeation capacity of FB-NPs nanocomposite gels with different cryoprotectants allowed us to conclude that these formulations are suitable topical delivery systems for human and veterinary medicine. However, there were statistically significant differences in the permeation of each formulation depending on the skin. Results suggested that FB-NPs-PEG nanocomposite gel was most suitable for human and porcine skin, and the FB-NPs-TRE nanocomposite gel was most suitable for bovine skin.

Evaluation of incipient enamel-carious–like lesion treated with hydroxyapatite-chitosan nanocomposite hydrogel

Non-invasive restoration of tooth enamel is a topic of high relevance in dental material science. Multiple approaches have been proposed to reach optimum reconstruction results. The current study was performed to evaluate the cross-sectional microhardness besides mineral quality and content in artificially induced carious enamel after treatment with hydroxyapatite-chitosan (HAp-CS) nanocomposite gel. Artificially carious lesions were induced by immersion of teeth in acidic carboxymethyl cellulose gel (pH 4.95-5) for 24- and 72-hours periods. Two different compositions of HAp-CS nanocomposite hydrogel were prepared with two different ratios 50/50 (%) and 70/30 (%), respectively. Additionally, sodium fluoride gel (1000 ppm concentration) was prepared and used as reference. Gels were applied to carious lesions twice/day for 3 min/each. After 45 days of application, surface morphology, energy dispersive x-ray spectroscopy, micro-Raman analysis in addition to cross-sectional microhardness were evaluated. Statistical analysis was performed using two-way ANOVA and Tukey's post hoc statistical tests. Surface morphological evaluation of treated surfaces showed obliteration of surface irregularities. Groups demineralized for 24 hours and treated with 70/30 (HAp-CS) showed highest significant cross-sectional-microhardness (P ≤ 0.05). Evaluated subsurface cross-sectional microhardness showed better mineral quality for groups demineralized for 24 hours and treated with HAp-CS nanocomposite gels. Nanocomposite gel with 70/30 (HAp-CS) could efficiently improve cross-sectional microhardness and both minerals composition and quality for lesions demineralized for 24 hours. More severely induced lesions, as demineralized for 72 hours, need more powerful agent compositions and/or prolonged application protocols for improvement.

Chitosan-Aloe Vera Composition Loaded with Zinc Oxide Nanoparticles for Wound Healing: In Vitro and In Vivo Evaluations.

Global concerns due to the negative impacts of untreatable wounds, as well as the growing population of these patients, emphasize the critical need for advancements in the wound healing materials and techniques. Nanotechnology offers encouraging avenues for improving wound healing process. In this context, nanoparticles (NPs) and certain natural materials, including chitosan (CS) and aloe vera (AV), have demonstrated the potential to promote healing effects. The objective of this investigation is to assess the effect of novel fabricated nanocomposite gel containing CS, AV, and zinc oxide NPs (ZnO NPs) on the wound healing process. The ZnO NPs were synthesized and characterized by X-ray diffraction and electron microscopy. Then, CS/AV gel with different ratios was prepared and loaded with ZnO NPs. The obtained formulations were characterized in vitro based on an antimicrobial study, and the best formulations were used for the animal study to assess their wound healing effects in 21 days. The ZnO NPs were produced with an average 33 nm particle size and exhibited rod shape morphology. Prepared gels were homogenous with good spreadability, and CS/AV/ZnO NPs formulations showed higher antimicrobial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The wound healing findings showed significant wound area reduction in the CS/AV/ZnO NPs group compared to negative control at day 21. Histopathological assessment revealed the advantageous impact of this formulation across various stages of the wound healing process, including collagen deposition (CS/AV/ZnO NPs (2 : 1), 76.6 ± 3.3 compared to negative control, 46.2 ± 3.7) and epitheliogenesis (CS/AV/ZnO NPs (2 : 1), 3 ± 0.9 compared to negative control, 0.8 ± 0.8). CS/AV gel-loaded ZnO NPs showed significant effectiveness in wound healing and would be suggested as a promising formulation in the wound healing process. Further assessments are warranted to ensure the robustness of our findings.

Polydopamine nanoparticles cross-linked hyaluronic acid photothermal hydrogel with cascading immunoinducible effects for in situ antitumor vaccination

Tumor vaccine, which can effectively prevent tumor recurrence and metastasis, is a promising tool in tumor immunotherapy. However, heterogeneity of tumors and the inability to achieve a cascade effect limit the therapeutic effects of most developing tumor vaccine. We have developed a cascading immunoinducible in-situ mannose-functionalized polydopamine loaded with imiquimod phenylboronic hyaluronic acid nanocomposite gel vaccine (M/P-PDA@IQ PHA) through a boronic ester-based reaction. This reaction utilizes mannose-functionalized polydopamine loaded with imiquimod (M/P-PDA@IQ NAs) as a cross-linking agent to react with phenylboronic-grafted hyaluronic acid. Under near-infrared light irradiation, the M/P-PDA@IQ PHA caused local hyperthermia to trigger immunogenic cell death of tumor cells and tumor-associated antigens (TAAs) releasing. Subsequently, the M/P-PDA@IQ NAs which were gradually released by the pH/ROS/GSH-triggered degradation of M/P-PDA@IQ PHA, could capture and deliver these TAAs to lymph nodes. Finally, the M/P-PDA@IQ NAs facilitated maturation and cross-presentation of dendritic cells, as well as activation of cytotoxic T lymphocytes. Overall, the M/P-PDA@IQ PHA could serve as a novel in situ vaccine to stimulate several key nodes including TAAs release and capture, targeting lymph nodes and enhanced dendritic cells uptake and maturation as well as T cells activation. This cascading immune activation strategy can effectively elicit antitumor immune response.

Rapid self-healing nanocomposite gel crosslinked by LDH for lost circulation control

Lost circulation presents a complex challenge in drilling operations. Ascribed to the favorable remaining in fracture, strong resistance to efflux, and entire gel block rather than individual particles, the self-healing gels have been broadly applied as lost circulation material (LCM). In this study, we utilized layered bimetallic hydroxide (LDH) as a dynamic crosslinking agent to synthesize a novel nanocomposite (NC) gel through in-situ polymerization following the stripping of LDH in acrylic acid (AA) solution. LDH/PAA NC gels exhibit excellent self-healing properties, rheological strength, mechanical properties and adhesion properties, with these attributes being influenced by the LDH content. At 110 °C, the optimal LDH/PAA NC gel rapidly self-healed in bentonite mud within 1 h, revealing storage modulus (G′) of 4041 Pa, tensile strength of 8.04 kPa, and adhesion strength of 2.1 kPa. Visual plugging tests revealed that the LDH/PAA NC gel could withstand pressures up to 4 MPa, surpassing the capabilities of MA gel, which lacked self-healing properties. These findings highlight the potential of LDH/PAA NC gels as efficient LCM, offering a promising solution for controlling lost circulation during drilling operations.

Carbon ion mono-energetic and spread-out Bragg peak measurements using nanocomposite Fricke gel dosimeters with LET-independent response

This study investigates the LET-dependence of dose measurements performed with a nanocomposite Fricke gel (NC-FG) upon irradiation with carbon ion beams to address the problem of quenching of gel dosimeters in high-LET particle therapy. The preparation of the NC-FG in a simple gel preparation device was performed for atmospheric and anoxic environmental conditions and two different container materials. Irradiation was performed with carbon ion beams at energies of 133.39MeV/u or 194.87MeV/u, complemented by a modulated 10 mm carbon ion spread-out Bragg peak (SOBP) irradiation. The R1 profiles obtained from the MRI readout were compared to the treatment planning system and a 2D-ionisation chamber array measurement performed for the mono-energetic and SOBP irradiations, respectively. For different dose levels, no difference in the gel response was obtained for the 3D-printed plastic containers, while the glass vials exhibited a linear dose response. Additional use of the glove box changes produced similar results. For both the mono-energetic and the SOBP irradiation, a linear dose response without quenching was observed. For depths ranging up to the Bragg peak position, the mono-energetic profiles deviated by less than ±15% from the planned dose distribution, excluding the lowest entrance surface dose (ESD). For the SOBP profiles, the deviation from the measured dose distribution was less than ±10% for depths between 20 mm and 33 mm. This study presents a LET-independent measurement of mono-energetic carbon ion Bragg peaks and, for the first time, a LET-independent measurement of a carbon ion SOBP with the NC-FG prepared in a simple gel preparation device under atmospheric conditions. The NC-FG provides a possible solution for 3D dosimetry in carbon ion radiotherapy.

The Role of Gold - Silver Nanocomposite Gel versus Astragalus Polysaccharides on Healing Process of Experimentally Induced Wound in Albino Rats Pharmacological and Histological Comparative Study

The Role of Gold - Silver Nanocomposite Gel versus Astragalus Polysaccharides on Healing Process of Experimentally Induced Wound in Albino Rats Pharmacological and Histological Comparative Study

Multifunctional Self-Assembled Block Copolymer/Iron Oxide Nanocomposite Hydrogels Formed from Wormlike Micelles.

This article reports the preparation of multifunctional magnetic nanocomposite hydrogels formed from wormlike micelles. Specifically, iron oxide nanoparticles were incorporated into a temperature responsive block copolymer, poly(glycerol monomethacrylate)-b-poly(2-hydroxypropyl methacrylate) (PGMA-b-PHPMA), and graphene oxide (GO) dispersion at a low temperature (∼2 °C) through high-speed mixing and returning the mixture to room temperature, resulting in the formation of nanocomposite gels. The optimal concentrations of iron oxide and GO enhanced the gel strength of the nanocomposite gels, which exhibited a strong magnetic response when a magnetic field was applied. These materials retained the thermoresponsiveness of the PGMA-PHPMA wormlike micelles allowing for a solid-to-liquid transition to occur when the temperature was reduced. The mechanical and rheological properties and performance of the nanocomposite gels were demonstrated to be adjustable, making them suitable for a wide range of potential applications. These nanocomposite worm gels were demonstrated to be relatively adhesive and to act as strain and temperature sensors, with the measured electrical resistance of the nanocomposite gels changing with applied strain and temperature sweeps. The nanocomposite gels were found to recover efficiently after the application of high shear with approximately 100% healing efficiency within seconds. Additionally, these nanocomposite worm gels were injectable, and the addition of GO and iron oxide nanomaterials seemed to have no significant adverse impact on the biocompatibility of the copolymer gels, making them suitable not only for 3D printing in nanocomposite engineering but also for potential utilization in various biomedical applications as an injectable magnetic responsive hydrogel.

Development of dual-crosslinked nanocomposite gel for water management in high-temperature reservoirs

Due to their controllable gelation time and high gel strength, polymer gels are widely used in the oil and natural gas industry for sealing operations. Aiming at the problems of fast gelation time and poor stability of polymer gel when the temperature exceeds 120 °C, a dual-crosslinked nanocomposite gel for high-temperature reservoir water management was developed. Polymers, crosslinking agents, nanomaterials, and retarders were studied for the effects of the concentration of each component on the initial viscosity, gelation time, stability, and viscoelastic properties of the gel. The long-term stability and water-plugging adaptability were evaluated. FTIR and viscoelastic performance analyses clarified the mechanism of action. The gel strength and thermal stability enhancement mechanism was analyzed based on SEM. At 170 °C,the gelation time is 5 ∼ 10h after adding retarder and aging in formation water for 30 days resulted in dehydration rates within 10%. The injection volume of the plugging agent is 0.3 PV, and the plugging rate of sand-filled pipes with different permeability is above 97%. The elastic modulus of the terpolymer SAV333/phenol-formaldehyde system was increased by 10 times by resorcinol and SiO2. The enhancement mechanism is mainly due to the gel’s strong dendritic dual-crosslinked network structure and the dual role of hydrogen bonding and electrostatic attraction of SiO2. Dual-crosslinked nanocomposite gel (DCNG) has shown promising performance as sealing material in high-temperature and ultra-high-temperature reservoirs.

Performance effectiveness of nano-lignin in production of gel with nano-chitosan for controlling release of salicylic acid

This work deals with assessing the performance of lignin nanoparticles (LNPs) in solving the problem of using salicylic acid as an agrochemical compound, via controlling its release. LNPs, obtained from black liquor, have been used to develop new delivery systems. Gels from chelating of LNPs with chitosan or chitosan nanoparticles (Cs-NPs) in presence or absence of cationic starch are investigated to achieve this essential aim. The nanoparticles are examined by TEM, ATR-FTIR, and XRD techniques. Based on measurements of swelling, encapsulation, release profile, release kinetic modeling of salicylic acid (SA), infrared spectroscopy, thermo-gravimetric analysis and scanning electron microscope the behavior of the investigated nanocomposite gels is assessed. The results show that the SA release profile of Cs-NPs and its nanocomposite with LNPs in phosphate-buffered saline (PBS) (7.4) (51.5–69.4 %) is higher than that of the mixture of water and ethanol (34.9–50.4 %). The release profile in PBS (7.4) demonstrates a trend of prolonged SA release over a 48-hour period. Best control of the SA-release can be achieved by CsNPs-LNPs nanocomposite. Comparing the results with previous literature demonstrates the promising characteristics of these examined gel nanocomposites. The release of SA from nanocomposites is regulated by a diffusion mechanism and follows the Ritger-Peppas and Higuchi models for kinetic release.

Synthesis and assessment of novel Na2S dispersed high performance nanocomposite gel polymer electrolyte intended for sodium batteries and electric double layer capacitors

Sodium sulphide (Na2S) nanoparticles are synthesized by hydrothermal method and utilized for electrochemical application for the first time. A series of sodium-ion conducting nanocomposite gel polymer electrolytes (NCGPEs) incorporating poly (methyl methacrylate) i.e., (PMMA) as the polymer backbone, sodium tetrafluoro-borate (NaBF4) as the salt, tetraethylene glycol dimethyl ether (TEGDME) as the plasticizer, and Na2S as the active fillers, are fabricated and studied. The optimized electrolyte having PMMA/NaBF4/TEGDME matrix incorporated with 2.5 wt% Na2S nanoparticles exhibits a high ionic conductivity of 3.0 × 10−4 S cm−1, low activation energy of 0.13 eV and operating voltage range of ~2.8 V at ambient temperature. Thermal studies reveal that the fabricated NCGPEs have the ability to retain the gel phase up to 473 K. The X-ray diffraction (XRD) and Fourier transform Infra-red (FTIR) spectroscopy indicate changes in structure and the ion–filler–polymer interactions inside the synthesized NCGPEs. A proto-type sodium cell with an optimized NCGPE has an open circuit voltage of 2.3 V and a first discharge capacity of 205 mAh g−1. The electric double layer capacitor (EDLC) designed with optimized electrolyte has a specific capacitance of 58 F g−1 and is stable up to 2000 charge-discharge cycles.

Cryostructuring of Polymeric Systems: 67 Properties and Microstructure of Poly(Vinyl Alcohol) Cryogels Formed in the Presence of Phenol or Bis-Phenols Introduced into the Aqueous Polymeric Solutions Prior to Their Freeze-Thaw Processing.

Poly(vinyl alcohol) (PVA) physical cryogels that contained the additives of o-, m-, and p-bis-phenols or phenol were prepared, and their physico-chemical characteristics and macroporous morphology and the solute release dynamics were evaluated. These phenolic additives caused changes in the viscosity of initial PVA solutions before their freeze-thaw processing and facilitated the growth in the rigidity of the resultant cryogels, while their heat endurance decreased. The magnitude of the effects depended on the interposition of phenolic hydroxyls in the molecules of the used additives and was stipulated by their H-bonding with PVA OH-groups. Subsequent rinsing of such "primary" cryogels with pure water led to the lowering of their rigidity. The average size of macropores inside these heterophase gels also depended on the additive type. It was found also that the release of phenolic substances from the additive-containing cryogels occurred via virtually a free diffusion mechanism; therefore, drug delivery systems such as PVA cryogels loaded with either pyrocatechol, resorcinol, hydroquinone, or phenol, upon the in vitro agar diffusion tests, exhibited antibacterial activity typical of these phenols. The promising biomedical potential of the studied nanocomposite gel materials is supposed.

A Review on the Mullins Effect in Tough Elastomers and Gels

AbstractTough elastomers and gels have garnered broad research interest due to their wide-ranging potential applications. However, during the loading and unloading cycles, a clear stress softening behavior can be observed in many material systems, which is also named as the Mullins effect. In this work, we aim to provide a complete review of the Mullins effect in soft yet tough materials, specifically focusing on nanocomposite gels, double-network hydrogels, and multi-network elastomers. We first revisit the experimental observations for these soft materials. We then discuss the recent developments of constitutive models, emphasizing novel developments in the damage mechanisms or network representations. Some phenomenological models will also be briefly introduced. Particular attention is then placed on the anisotropic and multiaxial modeling aspects. It is demonstrated that most of the existing models fail to accurately predict the multiaxial data, posing a significant challenge for developing future anisotropic models tailored for tough gels and elastomers.