Imine Groups Research Articles

Development of New N-{4-[(7-Chloro-5-methylpyrrolo[2,1-f] [1,2,4]triazin-4-yl)oxy]-3-fluorophenyl}benzenesulfonamide Analogues: Exploring Anticancer Potential through MerTK Inhibition

AbstractMer proto-oncogene tyrosine-protein kinase (MerTK), a part of the TAM (TYRO3, AXL, and MerTK) family, is directly correlated with metastasis and various types of cancers. The inhibition of this receptor is a promising strategy for more-effective chemotherapy. Considering the pharmacophoric features of the active domain of MerTK and the structural characteristics of the investigational drug BMS794833, we designed five new N-{4-[(7-chloro-5-methylpyrrolo[2,1-f][1,2,4]triazin-4-yl)oxy]-3-fluorophenyl}benzenesulfonamide analogues. In cytotoxicity studies, one of the analogues displayed a significantly higher cytotoxicity than cisplatin. It showed IC50 values of 2.09, 1.96, and 3.08 μM against A549, MCF-7, and MDA-MB-231 cancer cell lines, respectively. In drug metabolism and pharmacokinetic studies, it was the most stable analogue and displayed a moderate MerTK inhibitory potential. Molecular-docking studies were performed to corroborate the MerTK inhibition, and the same analogue achieved the most significant docking score (–12.33 kcal/mol). Docking interactions demonstrated that the imine and amine group of the 3-chloropyridine moiety of BMS794833 formed hydrogen bonds with the main chain of the ATP pocket residue Met674, while the oxygen atoms of the 4-oxo-1,4-dihydropyridine-3-carboxamide moiety established hydrogen bonds with the Lys619 and Asp741 amino acid residues of the allosteric pocket of MerTK protein. These promising results provide evidence that the N-{4-[(7-chloro-5-methylpyrrolo[2,1-f][1,2,4]triazin-4-yl)oxy]-3-fluorophenyl}benzenesulfonamide pharmacophore can give potential insights into the development of new MerTK inhibitors.

8-Aminoquinoline derived two Schiff base platforms: Synthesis, characterization, DFT insights, corrosion inhibitor, molecular docking, and pH-dependent antibacterial study

The current research divulges the synthesis of two new Schiff base (SB) (LNAPH/LO-VAN) derived from 8-aminoquinoline (8-AMQ) in the presence of 2-hydroxy naphthaldehyde (NAPH) and ortho-vanillin (O-VAN) in CH3OH solvent. They are structurally characterized by spectroscopic methods (IR/Raman/UV–vis/DRS/NMR) and SEM-EDX. SB compounds have a biologically active avenue of azomethine/imine group (H–C=N) that can donate N e's to Mn + ions, showing coordinating flexibility. The –OH and imine (H–C=N) groups are stable in air, light, and alkalis but undergo acidic environments hydrolysis, separating –NH2 and carbonyl compounds. Moreover, buffer solutions with a pH range of 4–6 release aldehyde. Molecular electrostatic potential (MEP), Frontier molecular orbitals (FMO), Fukui function, and Non-linear optical (NLO) were conducted to elucidate SBs chemical potency, optoelectronic significance, and corrosion inhibitor. Accordingly, the calculated ΔE of FMO for LNAPH and LO-VAN is 3.82 and 4.08 eV, ensuring potent biological function. DFT supported the experimental and theoretical IR spectral correlation to enrich better structural insights. NLO-based polarizability (α) and hyperpolarizability (β) factors successfully explore the potential optoelectronic significance. Molecular docking experiments were simulated against DNA, anti-COVID-19, and E. coli. The potential microbiological activity was screened against the bacterial strains E. coli, Klebsiella, Bacillus, and Pseudomonas sp. based on zone of inhibition and MIC values. These experiments also explored the fact that LNAPH and LO-VAN discourage microbial cell biofilms and corrosion. We extensively covered the as-prepared compounds' pH-dependent bacterial effects.

A Comprehensive on Synthesis and Antimicrobial Evaluation of Substituted-Arylideneamino-5-(5-Chlorobenzofuran-2-yl)-1, 2, 4-Triazole-3-Thiol Derivatives/ Schiff Bases.

Schiff bases are well known and popular classes of organic compounds containing imine (R2C = NH) group that are widely used as catalysts and intermediates in numerous organic transformations. Schiff bases are medicinally very important because they exhibit antimicrobial like antibacterial, antiviral and anticancer activities. Benzofuran based Schiff bases have been found as interesting scaffolds for the synthesis and design of biologically active agents. Moreover, they possess a wide range of biological activities against fungal, bacterial, malarial, inflammatory and viral diseases. In this reviw, substituted-arylideneamino-5-(5-chlorobenzofuran-2-yl)-1,2,4-triazole-3-thiols have been synthesized by using efficient synthetic protocols. The synthesized derivatives are also evaluated against different bacterial strains.

Free-standing COF nanofiber in ion conductive membrane to improve efficiency of vanadium redox flow battery

The ion sieving effect of the porous two-dimensional covalent organic frameworks (COFs) in vanadium redox flow battery (VRFB) was greatly restricted by the brittleness and easy agglomeration of COFs in ion conductive membranes. Herein, the strategy of free-standing COF nanofiber as continuous ion conductive pathways is proposed to maximize the selective ion conduction of COFs. The free-standing TFP-TAPA electrospun COF nanofiber mat was fabricated by an in-situ growth-template etching method, densified with sulfonated polybenzimidazole (SPBI) and continuously dispersed in the membrane. Fibrillization gives rigid COF materials excellent flexibility to be freely bent, induces the orientated aggregation of sulfonic acid groups via hydrogen bonding for proton hopping, as well as the long-range vanadium ions repelling barrier via the sieving pores (6 Å) and Donnan effect of the imine groups in COF. The TFP-TAPA COF nanofiber continuous membrane shows 3 folds of H+/Vn+ selectivity over Nafion212, achieves excellent VRFB energy efficiency of about 80.5 % at 200 mA cm−2, which surpasses most state-of-the-art COFs based ion conductive membranes for VRFBs.

Fabrication of Ni-Polyaniline/Graphene Oxide Composite Electrode with High Capacitance and Water Splitting Activity.

The Ni-PANI@GO composite electrode was fabricated via cost effective electrodeposition technique. According to the XRD, FTIR, Raman, SEM, and XPS analyses revealed that the nickel doped PANI@GO composite has been fabricated on the surface of the nickel foam. Addition of nickel significantly enhanced interaction between graphene with PANI leading to higher degree of polyaniline doping though imine groups. Electrochemical investigation revelated the significant performance of the Ni-PANI@GO composite electrode, boosting an impressive capacitance of 4480 F/g at 40 A/g, surpassing previous Ni-foam-based binder-free electrodes. Notably, Ni-PANI@GO electrode displayed excellent catalytic activity in both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), generating a considerable volume of the gas bubbles at relatively modest overpotentials of 279 mV and 244 mV respectively. This event allows for the achievement of 20 mA cm-2 current density. Furthermore, in the laboratory-scale water electrolyzer, a low cell voltage of 1.72 V was achieved, facilitating a water-splitting current density of 20 mA cm-2. This study underscores the premising potential for the real-world device's application of the versatile Ni-PANI@GO composite electrode.

Synthesis, Characterization and Anticancer Activity of Chitosan Schiff Base / PEG Blend Doped with Gold and Silver Nanoparticles in Treatment of Breast Cancer Cell Line MCF-7

In the present study, chitosan Schiff base has been prepared from chitosan reaction with the para chloro benzaldehyde. The AuNPs and AgNPs were manufacture by extract of onion peels as a reducing agent. The AuNPs and AgNPs that have been synthesized were characterized through UV-vis spectroscopy the XRD analyses and SEM microscopy. The polymer blends of the chitosan / PEG has been prepared through using the approach of solution casting. Chitosan Schiff base / PEG Au and Ag nano-composites were synthesized nano composites and polymer blends have been characterized by FTIR which confirm the formation of Schiff base by revealing a new band of absorption at 1693 cm-1 as a result of the (C=N) imine group. FESEM, DSC and TGA confirms the thermal stability of the prepared polymer blends and nanocomposites, nano composites have shown good results in inhibiting breast cancer cell line MCF-7, IC50 of nanocomposite = 19.44 µg / mL.

Additive engineering by dicyandiamide for high-performance carbon-based inorganic perovskite solar cells

Hole transport layer (HTL)-free, all-inorganic CsPbIxBr3-x carbon-based perovskite solar cells (C-PSCs) have attracted much attention due to their low cost and excellent stability. The poor device efficiency is a barrier to constrain its commercialization, mainly due to the large amount of interfacial and bulk defects existed in inorganic perovskite films. In this study, an organic small molecule dicyandiamide (DCD) is added to the perovskite precursor as an additive to adjust the crystallization kinetics and passivate defects of inorganic perovskite films, simultaneously. It is demonstrated that the introduction of DCD can not only accelerate the transition process from intermediate-phase DMAPbI3 to inorganic perovskite, but also passivate defects through the Lewis acid-base interaction between cyano (CN), imine (CN) groups, and uncoordinated Pb2+. Meanwhile, the energy level alignment was optimized, which effectively improves the charge transport efficiency of CsPbIxBr3-x C-PSCs. As a result, optimized device shows an enhanced efficiency from 14.07% to 15.84%, accompanied by improved long-term stability.

Boron-mediated one-pot access to salicylaldehydes via ortho-C-H hydroxylation of benzaldehydes.

A novel protocol has been devised for the ortho-C-H hydroxylation of benzaldehydes. Directed by a transient imine group, the borylation of benzaldehydes, sequentially followed by the hydroxylation, furnishes diverse salicylaldehydes in a one-pot manner. The resultant salicylaldehydes could be readily applied in the downstream synthesis to produce bioactive molecules.

Activation of redox-active covalent organic frameworks enriched with imine and quinone sites towards high pseudocapacitance

Redox-active covalent organic frameworks (COFs) can promisingly provide pseudocapacitance for supercapacitors. However, the intrinsic poor electrical conductivity and the stacking feature of COFs usually lead to a low utilization rate of the redox-active sites in their structural units. Herein, we prepare redox-active COFs enriched with imine and quinone groups from tetramino-benzoquinone (TABQ) and 2,5-dihydroxyterephthalaldehyde (Dha) monomers. The in-situ polymerization of these COFs on multi-walled carbon nanotubes (MWCNTs) results in the sufficient π–π interaction between the TABQ-Dha COF and the MWCNTs. The accelerated transport of electrons and activation of the redox-active groups of the TABQ-Dha COFs are then achieved with the assistance of MWCNTs to achieve a boosted capacitance of 398 F g−1 at 1 A g−1 as compared to the pristine TABQ-Dha COF (3 F g−1). In-situ FTIR and CV results reveal that the electrode reactions involve the redox-active transformation of imine and quinone groups in TABQ-Dha-MWCNTs which were activated to provide rich pseudocapacitance. Asymmetric supercapacitors (ASCs) assembled with graphene oxide (GO) supported TABQ (TABQ-GO) and TABQ-Dha-MWCNTs offers a high energy density of 12.8 Wh kg−1 at 750 W kg−1 and maintains a capacitance of 82.4 % after 20000 cycles at 5 A g−1, indicating its good potential towards practical application.

Imine-based conjugated polymer enables efficient removal of ammonium ion via capacitive deionization

The design of innovative faradaic electrode materials is crucial for improving the removal efficiency of contaminants in hybrid capacitive deionization (HCDI) systems. Organic compounds are a promising choice for faraday electrodes due to the sustainable production and tunable molecular structure. However, their high solubility in aqueous media and limited availability of redox-active sites for deionization greatly constrain the HCDI applications. Herein, we intentionally construct a conjugated polymer (IMP) with abundant imine groups, in which the strategic integration of N-heteroaromatic rings within the π-conjugated framework effectively prevents the disintegration of redox-active entities, while honing the energy bandgap and electronic characteristics. The copious redox-active CN sites within the imine groups along the polymeric chain markedly improve its capacity for the high-efficiency (de)intercalation of NH4+ ions. As an electrode material, the IMP polymer exhibits a significant NH4+-storage capacitance of 257.1 F g−1 at 2 A g−1 and maintains an ultra-cycle stability of 96.1 % after 10,000 cycles (4 A g−1), as evidenced by the in-situ spectral analysis of electrolyte. For real applications, a HCDI configuration has been constructed with a high specific NH4+ adsorption capacity of 119.0 mg g−1 and a fast removal rate of 27.0 mg g−1 min−1 with stable regeneration performance.

Machine learning powered CN-coordinated cobalt nanoparticles embedded cellulosic nanofibers to assess meat quality via clenbuterol monitoring

The World Anti-Doping Agency (WADA) has prohibited the use of clenbuterol (CLN) because it induces anabolic muscle growth while potentially causing adverse effects such as palpitations, anxiety, and muscle tremors. Thus, it is vital to assess meat quality because, athletes might have positive test for CLN even after consuming very low quantity of CLN contaminated meat. Numerous materials applied for CLN monitoring faced potential challenges like sluggish ion transport, non-uniform ion/molecule movement, and inadequate electrode surface binding. To overcome these shortcomings, herein we engineered bimetallic zeolitic imidazole framework (BM-ZIF) derived N-doped porous carbon embedded Co nanoparticles (CN-CoNPs), dispersed on conductive cellulose acetate-polyaniline (CP) electrospun nanofibers for sensitive electrochemical monitoring of CLN. Interestingly, the smartly designed CN-CoNPs wrapped CP (CN-CoNPs-CP) electrospun nanofibers offers rapid diffusion of CLN molecules to the sensing interface through amine and imine groups of CP, thus minimizing the inhomogeneous ion transportation and inadequate electrode surface binding. Additionally, to synchronize experiments, machine learning (ML) algorithms were applied to optimize, predict, and validate voltametric current responses. The ML-trained sensor demonstrated high selectivity, even amidst interfering substances, with notable sensitivity (4.7527 μA/μM/cm2), a broad linear range (0.002–8 μM), and a low limit of detection (1.14 nM). Furthermore, the electrode exhibited robust stability, retaining 98.07% of its initial current over a 12-h period. This ML-powered sensing approach was successfully employed to evaluate meat quality in terms of CLN level. To the best of our knowledge, this is the first study of using ML powered system for electrochemical sensing of CLN.

Synthesis of novel π-extended 2,5-disubstituted indolizines and their absorption and fluorescence properties

We report herein the synthesis of novel π-extended fluorescent 2-aryl-indolizines bearing substituents such as chalcone, styrene and imine groups at the C-5 position of the indolizine. Absorption and fluorescence properties of these 2,5-substituted indolizines were significantly affected by the substitution pattern at the C-5 position, as evidenced by absorption spectra, Stokes shifts and fluorescence measurements. Among the indolizine derivatives, those containing chalcone exhibited a highly notable red shift in their maximum wavelength of fluorescence (λem= 650 nm) compared to those containing imine (λem= 487 nm) or olefin (λem= 543 nm), accompanied by relatively large Stokes shifts (71-171 nm / 2955–6761 cm−1) and fluorescence quantum-yield values from 0.002 to 0.296. All synthesized indolizines demonstrated colorful in solution, while the imine- and olefin-substituted indolizines exhibited fluorescence both in solution and the solid state. The chalcone derivatives showcased the capability to regulate its fluorescence modulation. Although the presence of the carbonyl group extensively suppressed this effect, it was significantly restored upon reduction to the hydroxyl group, demonstrating a promisor “off-on” fluorescent sensors for monitoring oxidative processes within biological systems.

Synthesis of biscarbazole derivative, detection of the “on-off” sensor property of Cu2+ by fluorimetry, and anti-cancer evaluation

Biscarbazole derivative probe (6) (Z)-2-(3-(((9-heptyl-9H-carbazol-3-yl)methylene)amino)-9H-carbazol-9-yl)ethan-1-ol containing an imine group, which is a sensitive and selective fluorescence chemosensor, was designed and synthesized for the effective evaluation of Cu2+ metal ion levels. The synthesized compounds were characterized using 1H NMR, 13C NMR, FT-IR, and MALDI-TOF MS (for compound 6) spectroscopic data. The interaction model between probe 6 and Cu2+ was determined by combining fluorescence methods, 1H NMR titration, Job’s plot, and theoretical calculations. For probe 6, the fluorogenic recognition of Cu2+ was investigated by fluorescence spectroscopy, and the optical changes caused by Cu2+ ions were carried out in ACN/H2O (50:50) solution at pH 7.0. Fluorescence probe 6 was found to “turn-off” its fluorescence in the presence of paramagnetic Cu2+ ions. Probe 6 was determined to have a rapid response within 40s and showed a fluorescence response to Cu2+ with a low detection limit of 0.16 μM. Additionally, in vitro anticancer activity and cell imaging studies of probe 6 against the prostate cell line (PC-3) were performed.

Gelation and Plugging Performance of Low-Concentration Partially Hydrolyzed Polyacrylamide/Polyethyleneimine System at Moderate Temperature and in Fractured Low-Permeability Reservoir.

HPAM/PEI gel is a promising material for conformance control in hydrocarbon reservoirs. However, its use in low-permeability reservoirs is limited by the high polymer concentrations present. In this study, the gelation performance of an HPAM/PEI system with HPAM < 2.0 wt.% was systematically investigated. The gelation time for HPAM concentrations ranging from 0.4 to 2.0 wt.% varied from less than 1 h to 23 days, with the highest gel strength identified as grade H. The hydrodynamic radius manifested the primary effect of HPAM on the gelation performance. Branched PEI provided superior gelation performance over linear PEI, and the gelation performance was only affected when the molecular weight of the PEI varied significantly. The optimal number ratio of the PEI-provided imine groups and the HPAM-provided carboxylic acid functional groups was approximately 1.6:1~5:1. Regarding the reservoir conditions, the temperature had a crucial effect on the hydrodynamic radius of HPAM. Salts delayed the gelation process, and the order of ionic influence was Ca2+ > Na+ > K+. The pH controlled the crosslinking reaction, primarily due to the protonation degree of PEI and the hydrolysis degree of HPAM, and the most suitable pH was approximately 10.5. Plugging experiments based on a through-type fracture showed that multi-slug plugging could significantly improve the plugging performance of the system, being favorable for its application in fractured low-permeability reservoirs.

Simultaneously improving interfacial adhesion and toughness of carbon fiber reinforced epoxy composites by grafting polyethyleneimine on the carbon fiber surface to construct a rigid‐flexible interface

AbstractChemical grafting is commonly employed to functionalize carbon fiber (CF) surface to enhance the interfacial properties of CF reinforced polymer composites (CFRP) by forming a robust interface. However, an overly rigid interface layer can result in relatively poor interface toughness. To balance interfacial strength and toughness, this paper proposes an effective method to simultaneously strengthen and toughen the interface of CF/epoxy composites by grafting branched polyethyleneimine (PEI) on CF surface using hexachlorophosphazene (HCCP) as active intermediate, which features a rigid ring structure and six active P‐Cl groups. The introduction of PEI provided a large number of amine and imine groups on CF surfaces, which were contributive to improving surface wettability and reactivity of CF, thus resulting in strong chemical bonding between CF and epoxy matrix. Additionally, the long and flexible molecular skeleton of PEI constructed a rigid‐flexible composite interface, which could effectively reduce stress concentration and absorb impact energy. After surface modification with PEI, the interfacial shear strength and fracture toughness of CF/epoxy composite were increased to 89.9 MPa and 200.3 J m−2, by 64.3% and 149.7%, respectively, in compared with desized CF reinforced epoxy composites.Highlights A rigid‐flexible interface was constructed between CF and epoxy resin. The interfacial strength and toughness of CFRP were synergistically improved. IFSS and interfacial toughness increased by 64.3% and 149.7%, respectively.

Eco-friendly engineering of micro composite-based hydroxyapatite bio crystal and polyaniline for high removal of OG dye from wastewater: Adsorption mechanism and RSM@BBD optimization

The presence of harmful substances such as dyes in water systems poses a direct threat to the quality of people's lives and other organisms living in the ecosystem. Orange G (OG) is considered a hazardous dye. The existing paper attempts to evaluate a low-cost adsorbent for the effective removal of OG dye. The developed adsorbent Polyaniline@Hydroxyapatite extracted from Cilus Gilberti fish Scale (PANI@FHAP) was elaborated through the application of the in situ chemical polymerization method to incorporate PANI on the surface of naturally extracted hydroxyapatite FHAP. The good synthesis of PANI@FHAP was evaluated through multiple techniques including X-ray diffraction (XRD), Scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM/EDS), Fourier Transforms Infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) coupled with thermal differential analysis (DTA) analysis. The results reveal a highly ordered disposition of PANI chains on FHAP, resulting in a well-coated FHAP in the PANI matrix. Furthermore, the presence of functional groups on the surface of PANI such as amine (-NH2) and imine (=NH) groups would facilitate the removal of OG dye from contaminated water. The adsorption of OG onto PANI@FHAP was conducted in batch mode and optimized through response surface methodology coupled with box-Behnken design (RSM/BBD) to investigate the effect of time, adsorbent dose, and initial concentration. The outcomes proved that OG adsorption follows a quadratic model (R2 = 0.989). The kinetic study revealed that the adsorption of OG fits the pseudo-second-order model. On the other hand, the isotherm study declared that the Freundlich model is best suited to the description of OG adsorption. For thermodynamic study, the adsorption of OG is spontaneous in nature and exothermic. Furthermore, the regeneration-reusability study indicates that PANI@FHAP could be regenerated and reused up to five successive cycles. Based on the FTIR spectrum of PANI@FHAP after OG adsorption, the mechanism governing OG adsorption is predominantly driven by π-π interaction, electrostatic interaction, and hydrogen bonding interactions. The obtained results suppose that PANI@FHAP adsorbent can be a competitive material in large-scale applications.

Synthesis, Docking, and DFT Studies on Novel Schiff Base Sulfonamide Analogues as Selective COX-1 Inhibitors with Anti-Platelet Aggregation Activity.

Selective COX-1 inhibitors are preferential therapeutic targets for platelet aggregation and clotting responses. In this study, we examined the selective COX-1-inhibitory activities of four newly synthesized compounds, 10-13, along with their abilities to inhibit platelet aggregation against ADP and collagen. The target compounds 10-13 were synthesized using the conventional method, sonication, and microwave-assisted methods. Microanalytical and spectral data were utilized to elucidate the structures of the new compounds 10-13. Additionally, a spectral NMR experiment [NOESY] was conducted to emphasize the configuration around the double bond of the imine group C=N. The obtained results revealed no observed correlation between any of the neighboring protons, suggesting that the configuration at the C=N double bond is E. Biological results revealed that all the screened compounds 10-13 might serve as selective COX-1 inhibitors. They showed IC50 values ranging from 0.71 μM to 4.82 μM against COX-1 and IC50 values ranging from 9.26 μM to 15.24 μM against COX-2. Their COX-1 selectivity indices ranged between 2.87 and 18.69. These compounds show promise as promising anti-platelet aggregation agents. They effectively prevented platelet aggregation induced by ADP with IC50 values ranging from 0.11 μM to 0.37 μM, surpassing the standard aspirin with an IC50 value of 0.49 μM. Additionally, they inhibited the platelet aggregation induced by collagen with IC50 values ranging from 0.12 μM to 1.03 μM, demonstrating superior efficacy compared to aspirin, which has an IC50 value of 0.51 μM. In silico molecular modeling was performed for all the target compounds within the active sites of COX-1 and COX-2 to rationalize their selective inhibitory activities towards COX-1. It was found that the binding interactions of the designed compounds within the COX-1 active site had remained unaffected by the presence of celecoxib. Molecular modeling and DFT calculations using the B3LYP/6-31+G (d,p) level were performed to study the stability of E-forms with respect to Z-forms for the investigated compounds. A strong correlation was observed between the experimental observations and the quantum chemical descriptors.

Effect of stabilization and carbonization treatment on the chemical and physical transformation of polyacrylonitrile (PAN) based electrospun carbon nanofibers

The present study delves into the production of carbon nanofibers (CNFs) utilising electrospun polyacrylonitrile (PAN) nanofiber mats, with a specific focus on the influence of oxidative stabilisation and carbonisation treatments. This research aims to thoroughly understand how variations in stabilisation time and temperature, as well as carbonisation temperature, impact the CNFs properties. These properties include fiber size, morphology, chemical and crystal structure transformation, thermal behaviour, and surface characteristics. Our methodology involved a detailed examination of the thermal treatment processes, where we observed a significant decrease in fiber size, though the surface morphology of the fibers remained largely unaffected. We employed Fourier-transform infrared (FTIR) spectroscopy to track the transformation of nitrile groups in PAN to imine groups, which indicated the progression of cyclisation reactions. Complementary analyses through differential scanning calorimetry (DSC) confirmed a high degree of these reactions, particularly at stabilisation temperatures extending to 250 °C and beyond. The cyclisation process was found to be complete during the carbonisation phase, at temperatures reaching 450 °C and above. Further, x-ray diffraction (XRD) patterns offered insight into the changes in the crystal structure, particularly in the packing of the d(002) spacing because of the stabilisation and carbonisation processes. This findings from this study not only elucidate the intricate process of CNFs production from electrospun PAN nanofiber mats but also highlight the critical factors that influence their final properties. These insights are invaluable for the development of advanced CNFs with tailored properties suitable for a range of applications, including but not limited to energy storage, electronics, and as supporting materials in various technological domains.

Hydrophobic hypercrosslinked polymers prepared by secondary pore-forming method as excellent toluene adsorbents

In this work, inspired by molecular imprinting technology, we developed a secondary pore-forming method to chemically etch three hypercrosslinked polymers which are constructed from three novel hexapolar monomers containing imine groups, resulting in three novel hydrophobic porous hyper-crosslinked polymers (HCPs) pGly-TPA, pP-TPA and pBP-TPA. The structures were determined by FT-IR and solid-state 13C NMR spectroscopic techniques. The specific surface areas of pGly-TPA, pP-TPA and pBP-TPA are 694.1, 197.9 and 497.7 m2/g, respectively. All three porous polymers exhibit high hydrophobic properties with wetting angles of much greater than 90°. The breakthrough adsorption experiments revealed that the three prepared polymers exhibited significant adsorption capacity for toluene (322.05 mg/g for pGly-TPA, 114.43 mg/g for pP-TPA and 279.14 mg/g for pBP-TPA), but showed almost no adsorption for ethyl acetate, cyclohexane, and n-hexane, exhibiting certain molecular size and polarity selectivity. The adsorption behaviors of toluene on pGly-TPA, pP-TPA and pBP-TPA can be fit by the Boltzmann model and the Yoon-Nelson model, suggesting that the fixed bed has low mass transfer resistance. The adsorption rate is controlled by both external diffusion and intraparticle diffusion, as shown by the intraparticle diffusion model analysis. In addition, the adsorption capacity of toluene on pGly-TPA is almost unchanged under high humidity (70 %) or five adsorption–desorption processes, which demonstrates exceptional water-resistance and stability. This work is a reference for preparing novel hydrophobic HCPs using the secondary pore-forming method for removing VOCs from humid air.

Fabrication of Large‐Area Multi‐Stimulus Responsive Thin Films via Interfacially Confined Irreversible Katritzky Reaction

AbstractFabrication of large‐area thin films through irreversible reactions remains a formidable task. This study reports a breakthrough strategy for in situ synthesis of large‐area, free‐standing, robust and multi‐stimulus responsive thin films through a catalyst‐free and irreversible Katritzky reaction at a liquid–liquid interface. The as resulted films are featured with adjustable thickness of 1–3 μm and an area up to 50 cm2. The thin films exhibit fast photo‐mechanical motions (a response time of ca 0.1 s), vapor‐mechanical motions, as well as photo‐chromic and solvato‐chromic behaviors. It was revealed that the reason behind the observable motions is proton transfer from the imine groups to the carbonyl structures within the film induced by photo‐ and/or dimethyl sulfoxide‐stimulus. In addition, the films can harvest anionic radicals and the radicals as captured can be efficiently degraded under UV light illumination. This study provides a new strategy for fabricating smart thin films via interfacially confined irreversible Katritzky reaction.