Solvents Xylene Research Articles

Diffusion Behavior of Organic Solvents in Graphene Oxide/Nano Silica Hybrid Natural Rubber Latex Nanocomposite: Experimental and Theoretical Approach

AbstractThis study explores the impact of a graphene oxide (GO)/nano silica (NS) hybrid (GO/NS) filler on the diffusion characteristics of natural rubber (NR) composites when exposed to toluene, xylene, and hexane solvents. The lowest solvent uptake is observed for NR GO/NS 3 (3 phr), which is attributed to forming a robust filler network within the composite. The calculation of crosslink density using the Flory‐Rehner equation reveals significantly higher values for NR GO/NS 3, indicating good crosslinking density in the presence of the hybrid filler. Furthermore, molecular mass between crosslinks (Mc) is calculated, demonstrating a favorable fit with the Affine model. The investigation extends to theoretical modeling, where the Korsemeyer–Peppas and Peppas–Sahlin models are employed to predict solvent uptake behavior. Strikingly, the experimental values exhibit a strong alignment with the Peppas–Sahlin model. This comprehensive analysis provides valuable insights into the diffusion behavior of graphene oxide/nano silica (GO/NS) hybrid‐reinforced natural rubber latex in organic solvents, highlighting potential applications in areas such as solvent‐resistant coatings, barrier materials for chemical storage, and enhanced performance in protective gloves and seals used in harsh chemical environments.

Optimising Recycling Processes for Polyimine-Based Vitrimer Carbon Fibre-Reinforced Composites: A Comparative Study on Reinforcement Recovery and Material Properties.

We investigated the recycling process of carbon fibre-reinforced polyimine vitrimer composites and compared composites made from virgin and recycled fibres. The vitrimer matrix consisted of a two-component polyimine-type vitrimer system, and as reinforcing materials, we used nonwoven felt and unidirectional carbon fibre. Various diethylenetriamine (DETA) and xylene solvent ratios were examined to find the optimal dissolution conditions. The 20:80 DETA-xylene ratio provided efficient dissolution, and the elevated temperature (80 °C) significantly accelerated the process. Scaling up to larger composite structures was demonstrated. Scanning electron microscopy (SEM) confirmed effective matrix removal, with minimal residue on carbon fibre surfaces and good adhesion in recycled composites. The recycled nonwoven composite exhibited a decreased glass transition temperature due to the residual solvents in the matrix, while the UD composite showed a slight increase. Dynamic mechanical analysis on the recycled composite showed an increased storage modulus for nonwoven composites at room temperature and greater resistance to deformation at elevated temperatures for the UD composites. Interlaminar shear tests indicated slightly reduced adhesion strength in the reprocessed composites. Overall, this study demonstrates the feasibility of recycling vitrimer composites, emphasising the need for further optimisation to ensure environmental and economic sustainability while mitigating residual solvent and matrix effects.

Electrohydrodynamic Inkjet Printing of Three-Dimensional Perovskite Nanocrystal Arrays for Full-Color Micro-LED Displays.

Perovskite nanocrystal (PeNC) arrays are showing a promising future in the next generation of micro-light-emitting-diode (micro-LED) displays due to the narrow emission linewidth and adjustable peak wavelength. Electrohydrodynamic (EHD) inkjet printing, with merits of high resolution, uniformity, versatility, and cost-effectiveness, is among the competent candidates for constructing PeNC arrays. However, the fabrication of red light-emitting CsPbBrxI(3-x) nanocrystal arrays for micro-LED displays still faces challenges, such as low brightness and poor stability. This work proposes a design for a red PeNC colloidal ink that is specialized for the EHD inkjet printing of three-dimensional PeNC arrays with enhanced luminescence and stability as well as being adaptable to both rigid and flexible substrates. Made of a mixture of PeNCs, polymer polystyrene (PS), and a nonpolar xylene solvent, the PeNC colloidal ink enables precise control of array sizes and shapes, which facilitates on-demand micropillar construction. Additionally, the inclusion of PS significantly increases the brightness and environmental stability. By adopting this ink, the EHD printer successfully fabricated full-color 3D PeNC arrays with a spatial resolution over 2500 ppi. It shows the potential of the EHD inkjet printing strategy for high-resolution and robust PeNC color conversion layers for micro-LED displays.

Synthesis, tribological properties and oxidative stability of polyol esters base oils containing pentaerythritol complex esters

The performance requirements for extreme pressure and anti-wear properties, as well as oxidative stability, are increasingly stringent for MIL-PRF-23699G Enhanced Ester (EE) for aviation turbine engine lubricants. An oligomerization reaction of pentaerythritol through direct esterification using pentaerythritol and dibasic acid catalyzed by tetrabutyl titanate in xylene solvent, was employed to achieve the low-polymerization reaction of dibasic acid and pentaerythritol. A two-step synthesis process yielded a mixed ester comprising dibasic acid pentaerythritol complex ester and pentaerythritol tetrapentanoate. These mixed esters demonstrate excellent viscosity-temperature performance and good oxidative stability, significantly enhancing the extreme load-carrying properties and anti-wear properties of pentaerythritol tetrapentanoate. Molecular dynamics (MD) calculations indicate that complex esters possess higher adsorption energy and molecular interaction energy, enhancing the possibility of ester molecules adsorbing on metal surfaces and producing stronger oil film that can withstand large loads. The novel 5 mm2/s pentaerythritol ester containing diacid pentaerythritol complex esters exhibits improved viscosity-temperature performance, high-temperature oxidation resistance, and better tribological properties. Therefore, the novel pentaerythritol esters show potential for application in 5 mm2/s EE aircraft engine lubricants.

Donor-Acceptor Copolymers with 9-(2-Ethylhexyl)carbazole or Dibenzothiophene-5,5-dioxide Donor Units and 5,6-Difluorobenzo[c][1,2,5]thiadiazole Acceptor Units for Photonics.

Semiconducting polymers, particularly of the third generation, including donor-acceptor (D-A) copolymers, are extensively studied due to their huge potential for photonic and electronic applications. Here, we report on two new D-A copolymers, CP1 and CP2, composed of different electron-donor (D) units: 9-(2-ethylhexyl)carbazole or dibenzothiophene-5,5-dioxide, respectively, and of 4,7-bis(4'-(2-octyldodecyl)thiophen-2'-yl)-5,6-difluorobenzo[c][1,2,5]thiadiazole building block with central 5,6-difluorobenzo[c][1,2,5]thiadiazole electron-acceptor (A) units, which were synthesized by Suzuki coupling in the high-boiling solvent xylene and characterized. The copolymers exhibited very good thermal and oxidation stability. A copolymer CP1 with different molecular weights was prepared in order to facilitate a comparison of CP1 with CP2 of comparable molecular weight and to reveal the relationship between molecular weight and properties. The photophysical, electrochemical, and electroluminescence properties were examined. Intense red photoluminescence (PL) with higher PL efficiencies for CP1 than for CP2 was observed in both solutions and films. Red shifts in the PL thin film spectra compared with the PL solution spectra indicated aggregate formation in the solid state. X-ray diffraction measurements revealed differences in the arrangement of molecules in thin films depending on the molecular weight of the copolymers. Light-emitting devices with efficient red emission and low onset voltages were prepared and characterized.

Percolation Effect on the Complex Permittivities of Polymer Blends.

This study focuses on the measurement and analysis of the complex permittivities of polymer blends using the field enhancement method (FEM). The blends, consisting of air-powder or solvent-solute mixtures, are placed in a Teflon holder and inserted into the FEM cavity to determine the complex permittivity. The resonant frequency and quality factor of the FEM cavity coupled with the samples provide information on the blends' dielectric constant and loss tangents. To extract the complex permittivities of three specific samples of DC-840, MCL-805, and MCL-Siloxane, we employ effective medium theories and the high-frequency structure simulator (HFSS) together with the measured data. The results reveal that when the volume fraction of the DC-840 solute in the xylene solvent surpasses a specific threshold, the dielectric constants and the loss tangents experience a notable increase. This phenomenon, known as percolation, strongly correlates with the viscosity of polymer blends. The observed percolation effect on the dielectric behavior is further elucidated using the generalized dielectric constant and the Debye model. By employing these models, the percolation effect and its impact on the dielectric properties of the blends can be explained.

Mechanical properties and weather stability of a novel nanocomposite coating based on fluoroethylene/vinyl ether copolymer and organically modified zirconium dioxide nanoparticles

AbstractThis study aims to investigate the effect of organically modified zirconium dioxide nanoparticles (m‐ZrO2 NPs) on the mechanical properties, morphology, and weather stability of fluoroethylene/vinyl ether copolymer (FEVE). To modify the surface of ZrO2 NPs, a 3‐(trimethoxysilyl)propyl methacrylate silane (TMSPM) organic coupling agent was utilized. The ZrO2 NPs were treated with 3 wt.% of TMSPM using a solution method with ultrasonication assistance at 50°C. Various amounts of m‐ZrO2 NPs (1, 2, and 4 wt.% of FEVE weight) were dispersed in a xylene solvent and mixed with FEVE resin. The mixture was then cured with polyisocyanate. The mechanical properties of the FEVE nanocomposite coatings, including impact resistance, adhesion, and abrasion resistance were measured. The morphology of the coatings was analyzed using scanning electron microscopy (SEM). To evaluate the weather stability of the coatings, an accelerated weathering test was conducted in a QUV/SPRAY chamber. This test could potentially affect the chemical structure, weight/thickness, and surface characteristics of the coatings. The carbonyl index, weight loss, and changes in mechanical properties of the coatings were monitored and discussed at different intervals during the accelerated weathering test. In addition, the morphology of the coatings after undergoing 42 cycles of accelerated weathering testing was analyzed. The results indicated that m‐ZrO2 NPs had a positive impact on the weather durability of FEVE resin, particularly in significantly enhancing the weather resistance of the FEVE‐based coatings. Therefore, these coatings exhibit potential for outdoor applications.Highlights Silane modified ZrO2 nanoparticles improve the mechanical properties of FEVE resin. The weather stability of FEVE resin increases as using modified ZrO2 nanoparticles. The suitable content of modified ZrO2 nanoparticles for FEVE resin is 2 wt.%. Mechanical properties of the nanocomposite reduce slightly after 42 cycle testing. Propose the mechanism for weather resistance of the nanocomposite coating.

Evaluation cell surface hydrophobicity of four potential probiotics Lactic acid bacteria's isolated from local dairy products

The purpose of this study was to investigate the cell surface hydrophobicity of four Lactic acid bacteria (LAB) strains isolated from various traditional and industry fermented yogurt and cheese sources based on the biochemical tests. The determining cell surface hydrophobicity is a critical step in selecting LAB strains with probiotic qualities and is one of the most essential elements regulating LAB's particular adherence to abiotic surfaces, as well as one of the most critical factors controlling LAB's absorption and destruction of hydrophobic organic matter. In current study, the four LAB strains had high cell surface hydrophobicity to the four separate hydrocarbon solvents xylene, hexadecane, chloroform, ethyl acetate determined via spectrophotometer at 450 nm. The highest hydrophobicity score was determined for LB3 for chloroform, n- hexadecane, ethyl acetate and xylene at 66.51, 38.23, 33.67 and 24.18% respectively. LB3 demonstrated promising cell surface characteristics, suggesting that it could be used as an indigenous probiotic

Preparation of polyaniline‐poly(ethylene‐vinyl acetate) film: Resistivity in the ESD range

AbstractFilms of polyaniline (PANI) salt with poly (ethylene‐vinyl acetate) (EVA) with two different PANI salts, PANI‐methane sulfonic acid (PANI‐MSA) and PANI‐p‐toluene sulfonic acid (PANI‐PTSA) are prepared by solution processing technique for electrostatic discharge (ESD) application. PANI‐MSA/PANI‐PTSA salts were synthesized by emulsion polymerization pathway then dispersed the PANI salt in xylene solvent. EVA was dissolved in xylene solvent. Series of PANI salt/EVA films were prepared by mixing a particular amount of PANI dispersion to a fixed amount of EVA solution and evaporated the solvent. PANI‐EVA films were evaluated by tensile strength, elongation at break and surface resistivity measurements. The results of PANI‐MSA/EVA films are compared with the results of PANI‐PTSA/EVA films. Also, PANI‐MSA/EVA and PANI‐PTSA/EVA solutions are coated on different substrates and measured their electrical resistivity for ESD application. Morphological study and thermal behaviors of PANI‐MSA/EVA films are carried through FE‐SEM and TGA respectively. Sphere morphology of EVA changed to swollen sheet like morphology with the addition of PANI, and the spaces between the sheets increased with the increase in PANI content. The surface resistivity of the EVA‐PANI films are found to be in the range of 104–108 Ω sq−1, which is suitable for ESD application.

Effect of phytotherapy (Punica granatum L) on rabbits Oryctolagus cuniculus exposed to solvent xylene

Solvents have become a major threat to humanity, Xylene is one of the most used solvents in everyday life despite its toxicity, it had been used in many important products of human daily life such as paint, varnish, and many other products, but, there is what God created in nature "the pomegranate" which had considered among the most beneficial of medicinal plants. This work is based on the study of the remedial effect of pomegranate on the harmful effect of Xylene on certain reproductive parameters in rabbits of the species Oryctolagus Cuniculus. For four consecutive weeks, some rabbits received one dose of Xylene (0.5 ml/Kg), other rabbits received the same dose of Xylene and one dose of the juice of pomegranate (1ml/Kg) and controls received nothing. Our experience is based on the study of the weight of the reproductive organs: the testes and the epididymis, the study of the parameters of male fertility, and a histological study. The results show changes in the weight of the organs studied (testes and epididymis), and changes in male fertility parameters have been recorded. The hormone level (testosterone) has changed as well as a histological modification of the reproductive organs. Omit, these parameters have been corrected in their values due to the corrective effect of the pomegranate. In conclusion, this study demonstrated the adverse effects of Xylene exposure on reproduction, hormonal, and histological parameters. On the other hand, the pomegranate has a corrective effect on the previous parameters.

Building-up an interrelationship between isomeric benzyl inner side chains within nonfullerene acceptors and isomeric xylene solvents for non-chlorinated solvent-processed organic solar cells

Three isomeric BzY-series NFAs are developed by introducing inner benzyl side chains. Among the BzY-series NFA-based OSCs processed with non-chlorinated xylene solvents, PM6 : m-BzY exhibits PCE over 16% without an additive and thermal annealing process.

Fructobacillus trapaeoli - A fructophilic lactic acid bacteria isolated from Manilkara zapota

The study was undertaken to isolate and characterize fructophilic lactic acid bacteria from the fruit Manilkara zapota (chikoo). Microscopic, phenotypic, biochemical and molecular characterisation of the isolates was done. The Gram-positive thin rods (5 μm length and 0.25 μm thickness) were catalase and oxidase negative and did not hydrolyze arginine. The carbohydrate fermentation studies showed that the isolate preferred fructose similar to glucose as an energy source. The isolate had an optimum growth at 37ºC and also had grown at 45ºC. 16S rRNA sequencing confirmed the isolate as Fructobacillus tropaeoli DMM03 (NCBI accession number MT158673). There are very few reports of isolation and characterization of Fructobacillus from India. The osmotolerant nature of the isolate was established by its ability to grow in pH 5, 8 per cent NaCl, 35 per cent D-Fructose and 50 per cent D-Glucose. The isolate had also shown growth in the presence of heavy metals with a maximum concentration of 60 ppm cadmium and 2425 ppm lead. An autoaggregation of 46.3 per cent and cell surface hydrophobicity value of 22 per cent with apolar solvent xylene suggested the high adhesion potential. The isolate was found to be non-haemolytic and not liquefying gelatin which implies its safety in use for product preparation. The results point out a prospective area for future research in Fructobacillus tropaeoli DMM03 for tapping its potential in the field of probiotics and bioremediation.

Chemical route for synthesis of β-SiAlON:Eu2+ phosphors combining polymer-derived ceramics route with non-hydrolytic sol-gel chemistry

We report the synthesis of β-SiAlON:Eu2+ phosphors from novel single source precursors in which strictly controlled chemical composition is established at molecular scale. The two-step synthesis occurs by the chemical modification of perhydropolysilazane (PHPS) with Al(OCH(CH3)2)3 and AlCl3 in xylene at room temperature to 140 °C to introduce Al in the PHPS network while controlling the oxygen content followed by the reaction of EuCl2 with the Al-modified PHPS upon heat-treatment. Gas chromatography-mass spectrometry and thermogravimetry-mass spectrometry analyses revealed that PHPS reacted with Al(OCH(CH3)2)3 and AlCl3 via the formation of Al-N bonds. Moreover, AlCl3 reacted with nitrogen-bonded Al alkoxide residue to release 2-chloropropane in an analogy to the non-hydrolytic sol-gel reaction between metal alkoxide and metal chloride. Subsequently, AlCl3 acted as a Lewis acid catalyst to promote the Friedel-Craft alkylation between xylene solvent and the 2-chloropropane formed in-situ to afford dimethylcumene. On the other hand, EuCl2 reacted with silylamino moiety to form Eu-N bonds at around 850 °C. β-SiAlON:Eu2+ phosphors were successfully synthesized by pyrolysis of the precursors under flowing N2 or NH3 at 1000 °C, followed by heat treatment at 1800 °C for 1 h under a N2 gas pressure at 980 kPa. The polymer-derived β-SiAlON:Eu2+ (z = 0.55, Eu2+ 0.37 at%) exhibited green emission under excitation at 410 or 460 nm, and the green emission intensity under the excitation at 410 nm was found to be increased by reducing the carbon and chlorine impurities through the polymer-derived ceramics route investigated in this study.

Gas-to-aqueous Phase Transfer for Three Paint Solvents Injected into an Abiotic, Industrial Biotrickling Filter Measured with a Flame Ionization Detector

This is a knowledge contribution to the unsatisfactory biodegradation problem, when biotrickling filters are purifying mixed paint solvents. A biotrickling filter manufacturer reported low biodegradation rates during the purification of a hydrocarbon pollutant mix from an industrial paint spraying floor. From a gas chromatograph/mass spectrometer analysis both hydrophilic and hydrophobic solvents were found in the polluted air. It is known that biodegradation is retarded, if the pollutant does not transfer from gas to liquid into the biofilm and it was therefore suspected that hydrophobic pollutants do not sufficiently migrate into the water/biofilm. To test this hypothesis, pure, rather than mixed pollutants, were injected into the abiotic biotrickling filter. When hydrophobic paint solvent (xylene) was sprayed into the biotrickling filter, the solvent load at the outlet of the filter was almost as high as at the inlet. But when pure, hydrophilic paint solvent (PGME) was sprayed into the abiotic biotrickling filter, the solvent load measured at the outlet of the filter was zero, indicating complete dissolution into the circulation water. Carbon/solvent loads at the filter outlet and inlet were measured with a portable flame ionization detector instrument. The experiment confirms that the hydrophobic solvent does not migrate into the liquid phase. This poor mass transfer of hydrophobic solvents is likely to be the reason for the low biodegradation rate. The result is highly relevant to the paint spraying industry and manufacturers of exhaust gas treatment equipment alike, who spend millions in non-sustainable incineration of exhaust gases.

Calcium monofluoride as a target molecule for determination of organic fluorine in gasoline and its components using high-resolution continuum source flame molecular absorption spectrometry

High-resolution continuum source molecular absorption spectrometry (HR-CS MAS) is widely applied to determine fluorine in various materials, and its graphite furnace option with calcium monofluoride as a target molecule is popular. However, up to now, the idea of using the molecule in flame molecular absorption spectrometry seemed impossible or impractical due to the expected low sensitivity and detectability. The following paper completely changes this view. The CaF molecule has been proven to be an excellent tool for determining organic fluorine in gasoline using flame molecular absorption spectrometry, giving benefits over previously used gallium monofluoride. The following favourable circumstances decide about it: 1) relatively high population of CaF molecules in preferable air-acetylene flame, 2) possibility of using oil calcium “standard” as a source of calcium, which is well dissoluble in both xylene (solvent) and gasoline, 3) extremely good stability of baseline in the used spectrum range, 4) relatively high freedom from spectral and chemical interferences and 5) possibility of summing of many pixels response. The analysis relies on simple sample dilution in xylene, with the addition of oil calcium “standard” to obtain 1500 mg L−1 Ca in measured solutions. Simplified standard addition calibration is used to overcome the effect of variability of samples (various physical properties and combustion characteristics). The signals of four CaF rotational “lines” are summed. The only undesirable spectral effect is a molecular absorption at the second “line” (606.0368 nm), which is attributed to the absorption by the CaOH molecule formed in the flame. The effect can be easily overcome by using the least square background correction, LSBC. The characteristic concentration and the detection limit for solutions are 6 and 0.6 mg L−1, respectively. The detection limit recalculated for the original sample is 2 mg kg−1 in the case of alkalyte, reformate and gasoline, while it is 6 mg kg−1 in the case of volatile isomerizate, mainly due to necessary higher sample dilution. The calibration curve is linear over at least two orders of magnitude. Heptafluorobutanol has been found a suitable standard. The agreement of the results of the proposed method and standard combustion ion chromatography is satisfactory.

Self-assembly of C60 fullerene molecules in the hexane–xylene solvent system

The behavior of self-assembly of C60 molecules in solutions of C60/hexane/xylene were studied by the methods of refractometry, ultraviolet–visible spectroscopy and dynamic light scattering (DLS). It was experimentally shown that with a slight increase in either the concentration of fullerene C60 or the volume fraction of xylene in a C60/hexane/xylene solution, the refractive index of the medium increases. Increasing the xylene content of the C60/hexane/xylene system leads to significant changes in charge transfer between solute and solvent, which, in particular, exhibit both a positive solvatochromic effect and a hypochromic effect in a strong absorption band at ∼328.8 nm. It was established by the DLS method that with an increase in the concentration of C60 in the C60/hexane solution from 20 to 30 mg/dm3, the maximum radius of the synthesized nanoclusters in solutions changed from ∼6.25 nm to ∼17.2 nm, and also with an increase in the mole fraction of xylene in the C60/hexane/xylene system, the cluster size gradually decreases.

The influence of xylene content on the dispersion of graphene in aromatic petroleum resin by solution mixing

Graphene (Gr) uniformly dispersed aromatic petroleum resin (APR) coatings were prepared using exfoliated Gr and APR as raw materials by solution mixing method. Graphene was first mixed with the xylene solution and treated by ultrasonication. Then the APR was added to the mixture solution, after heating and stirring to remove the excess xylene solvent, the APR solution with uniform dispersion of graphene could be obtained. Atomic force microscopy (AFM) was used to test the thickness variation of the multilayer graphene layers before and after xylene adsorption. The results showed that the xylene which increased the thickness of the multilayer graphene was interspersed between the graphene layers. Raman spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) characterized that graphene obtained a good dispersion of Gr in APR. The electrochemical characteristics of graphene-modified APR coatings were tested by electrochemical impedance spectroscopy (EIS), and the results showed that the xylene content influenced the dispersion of graphene and flowability of the APR solution. The Gr/APR coatings with 45 wt% xylene exhibited the best corrosion protection performance. The impedance modulus of the coating in the low-frequency region after being immersed in 3.5 wt% sodium chloride solution for 100 days was greater than 109Ω·cm2.

A comparative study of the effects of gutta-percha solvents on human osteoblasts and murine fibroblasts.

We aimed to investigate the invitro physiologic effects of xylene, chloroform, orange oil and eucalyptus oil solvents for dissolving gutta-percha on L929 and HOB cell lines; 2.5 and 10 μL mL-1 of these solvents were tested for 24, 48 and 72 h. Gutta-percha solvents inhibited the proliferation rate of fibroblasts in a dose- and time-dependent manner; however, no inhibition was detected in HOB (evaluated using MTT assay). None of the solvents induced apoptosis/necrosis in HOB cells at ≤2.5 μL mL-1 concentration in contrast to L929 (determined using acridine orange/ethidium bromide dual staining). Each solvent tested reduced the migration rate of both L929 and HOB cell lines in a dose-dependent manner (evaluated using a scratch assay). Gutta-percha solvents can damage fibroblast-rich tissues. Osteoblasts seemed to be more resistant to the tested solvents, and excessive extrusion of solvents from the root canal may also damage the periradicular tissues and reduce the ability to repair.

Radical transformations of organic solvents under sub- and supercritical conditions

A comparative study of chemical transformations of ethanol, acetone and dimethyl carbonate was performed in a temperature range from 200 to 300 °C. These compounds are widely used as solvents for processing vegetable raw materials. Therefore, knowing their behaviour in a reaction medium is necessary to understand the mechanism of sub- and supercritical extraction of the vegetable raw materials and the role of solvents in this processуы. It was established that the investigated compounds under certain conditions function as a source of free radicals; thus, they can contribute to the radical decomposition of the major components in plant biomass. The Schwarz toluene method was used to detect free radicals in reaction media. It is shown that radical breakdown of bonds in the acetone and dimethyl carbonate molecules occurs already at a temperature of 200 °C, and in ethanol - only under supercritical conditions at temperatures over 250 °C. Alkylation is the main reaction occurring during the thermal treatment of toluene and solvents mixtures, which leads to a high yield of various alkylbenzenes for all investigated xylene solvents. In a temperature range from 200 to 250 °С, acetone has the highest alkylating capability and ethanol - the lowest one. At temperatures above 250 °С, the alkylating capability of solvents is similar, with a slight prevalence of that of dimethyl carbonate. Unlike other solvents, acetone participates in nucleophilic addition reactions along with radical transformations under process conditions. The products obtained as a result of these reactions at temperatures above 250 °C are predominant. The main ones are the products of the aldol and crotonic condensation of acetone. Based on the results of a study, the pathways of the radical decomposition of solvents molecules and the formation of products of thermal treatment were proposed.

Donor-Acceptor Complex Enables Cascade Radical Cyclization of N-Arylacrylamides with Katritzky Salts.

Cascade radical cyclization of N-arylacrylamides is an attractive method to prepare 3,3-disubstituted oxindoles. As the reported methods often require additives and/or photocatalysts, we herein report an additive- and photocatalyst-free deaminative strategy for their synthesis under mild conditions, enabled by photoactivation of an electron donor-acceptor (EDA) complex. DFT studies indicated that the involvement of an explicit xylene solvent molecule can greatly enhance the photoactivity of the EDA complex between N-arylacrylamides and Katritzky salts.