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Eugenol-containing oligoorganosilsesquioxanes were synthesized by the method of hydrolytic polycondensation in an active medium under various reaction conditions. The obtained products were characterized by 29Si NMR spectroscopy and MALDI-TOF spectrometry. It was shown that factors such as the reaction temperature, polycondensation duration, and molar ratio between the initial alkoxysilane monomer and acetic acid may affect the molecular weight characteristics and molecular structure of the formed oligomer, like the content of stressed cyclic units (T3, DTT, TDT) and unstressed silsesquioxane units TnDm. In particular, an increase in the ratio of the initial reagents led to an increase in the content of silsesquioxane Tn fragments from 28.2%mol to 41.7%mol, while the number of strained cyclic structures decreased by more than two times. An increase in the synthesis time is of no particular practical value since it was found that the composition of the oligomers synthesized for 6 h and 12 h was practically identical, as was that of the oligomers synthesized for 24 h and 48 h. A noticeable transition in the oligomer composition was observed only when the synthesis time was changed from 12 h to 24 h. Finally, it was shown that the choice of synthesis temperature had the strongest effect on the oligomer composition. The oligomer synthesized at 95 °C contained the highest amount of silsesquioxane Tn fragments, >77%mol, while a Tn fragment content of ~42%mol was observed during the synthesis at 117 °C. It was shown that silsesquioxanes are devitrified at room temperature (Tg from −6.4 to −10.6 °C), and their thermal stability in an inert atmosphere is 300 °C. The synthesized oligomers, due to the presence of hydroxyl-containing eugenol units, may be promising binders and additives for functional epoxy–silicone paints and coating materials. [ABSTRACT FROM AUTHOR]

The destruction of various structural materials and products in aggressive atmospheric conditions demands for the development of more resistant and improved oligomers and polymers for adhesive coatings with barrier properties, which could prevent corrosion and rapid aging of metals and polymers. In this article, we demonstrate the synthesis of novel polysilsesquioxane containing a covalently bonded eugenol, being a corrosion inhibitor of natural origin. The research demonstrates the synthesis of a monomer from eugenol and MPTMS by the UV‐initiated thiol‐ene reaction. Polysilsesquioxanes were synthesized by hydrolytic and acidohydrolytic polycondensation methods. The 29Si NMR spectroscopy shows the difference in the chemical structures of the obtained products. The synthesized polysilsesquioxanes have a glass transition temperature of −6.5 °C and −7.2 °C for hydrolytic and acidohydrolytic polycondensation, respectively. At the same time, rheokinetics shows a significant difference in the curing of polysilsesquioxanes obtained by two different methods in the temperature range of 150–190 °C. So, it was shown that the product obtained by acidohydrolytic polycondensation exhibited much lower ability for the formation of cross‐linked networks. The product, obtained by hydrolytic polycondensation, exhibited good coating performance, and the obtained coatings showed high anticorrosive efficiency. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO2 (eCO2RR) that exclusively produces one product at industrial current density is crucial for the substantial storage of renewable energy. Modulating the electronic structure of atomically dispersed catalysts can effectively regulate the adsorption of rate‐determining‐step intermediates to achieve the desired products. Here, the study constructs a hybrid catalyst consisting of single Ag atoms and Ag atomic clusters supported on nitrogen‐doped multi‐walled carbon nanotubes that can effectively regulate the important intermediate structure of *COOH. The X‐ray photoelectron and X‐ray absorption near‐edge spectroscopies demonstrate that turning Ag single atoms into Ag clusters can weaken the electron transfer between Ag–N and present a relatively rich electron state. Thus, the rate‐determining step of *COOH massive formation is significantly accelerated, as proven by in situ synchrotron infrared spectroscopy and density functional theory calculations. Using this strategy, a CO Faradaic efficiency outperforming 99% from −0.3 to −0.8 V (vs reversible hydrogen electrode) with current densities above 200 mA cm−2 and a half‐cell energetic efficiency of 86% is achieved. This work highlights a promising approach to advancing synergistic catalysts for achieving more controllable and efficient eCO2RR. [ABSTRACT FROM AUTHOR]

Preparation of hydrophobic coatings is still a challenge for researchers in various fields of science. One of the easiest ways consists of the use of special modifiers. However, usually such modifiers are poorly compatible with organic polymeric matrixes, which leads to segregation of modifiers and deterioration of coating properties. In this work, we have synthesized a number of organosilicon copolymers and studied their compatibility with epoxy matrix and hydrophobic efficiency. It was shown that the increase of phenyl-containing units leads to increase of compatibility but decreases hydrophobic efficiency. Addition of small amounts of such modifiers into commercial epoxy paint material can lead to an increase of contact angle of the final coating from 63 to 87° without deterioration of other physico-mechanical properties. These results open new perspectives in preparation of organosilicon hydrophobic modifiers with directed properties for fields of application such as paints and coating materials. [ABSTRACT FROM AUTHOR]

The development of advanced methods for the synthesis of nano- and microparticles in the field of biomedicine is of high interest due to a range of reasons. The current synthesis methods may have limitations in terms of efficiency, scalability, and uniformity of the particles. Here, we investigate the synthesis of submicron calcium carbonate using a microfluidic chip with a T-shaped oil supply for droplet-based synthesis to facilitate control over the formation of submicron calcium carbonate particles. The design of the chip allowed for the precise manipulation of reaction parameters, resulting in improved porosity while maintaining an efficient synthesis rate. The pore size distribution within calcium carbonate particles was estimated via small-angle X-ray scattering. This study showed that the high porosity and reduced size of the particles facilitated the higher loading of a model peptide: 16 vs. 9 mass.% for the particles synthesized in a microfluidic device and in bulk, correspondingly. The biosafety of the developed particles in the concentration range of 0.08–0.8 mg per plate was established by the results of the cytotoxicity study using mouse fibroblasts. This innovative approach of microfluidically assisted synthesis provides a promising avenue for future research in the field of particle synthesis and drug delivery systems. [ABSTRACT FROM AUTHOR]

One-dimensional magnetic nanomaterials, such as nanorods, are one of the most interesting but unexplored objects due to the complexity of their manufacture. In this work, we report on the template-assisted preparation of rod-shaped cobalt ferrite (CoFe2O4) nanoparticles (NPs) using the akaganeite (β-FeOOH) matrix and their application as multifunctional agents in biomedicine. In the beginning, rod-shaped β-FeOOH NPs are prepared by a forced hydrolysis technique. Then, amorphous Co-(OH)2 is deposited onto the surface of β-FeOOH. Finally, a solid-state reaction results in mesoporous rod-shaped (130 nm × 40 nm) CoFe2O4 NPs with a crystallite size of 7 nm. The proposed mechanism of synthesis involves the simultaneous transformation of β-FeOOH and amorphous Co-(OH)2 in two corresponding oxides during annealing, resulting in cation interdiffusion with the formation of a CoFe2O4 phase, while the key role of the Co-(OH)2 shell in preserving the rod-shaped morphology of CoFe2O4 NPs is demonstrated. NPs exhibit a high coercivity of 73 kA m–1 arising from their shape anisotropy, while their effective anisotropy constant of 1.1 × 105 J m–3 is compared to bulk CoFe2O4. Despite the low value of saturation magnetization (13 A m2 kg–1), NPs demonstrate dual-modal relaxivity in MRI experiments with high values of r1 = 2.3 s–1 mM–1 and r2 = 228 s–1 mM–1. Finally, we show that the magnetomechanical stimulus from NPs leads to the programmed death of breast cancer cells. Under the action of a low-frequency magnetic field (31 Hz), such NPs mediate mechanical vibrations, leading to cancer cell destruction even at a very low concentration of 6 μg CoFe2O4·mL–1. [ABSTRACT FROM AUTHOR]

The structure and properties of nanoparticles are greatly influenced by the synthesis method and the stabilizer used in their preparation. The paper presents the results of the effect of various stabilizers (gelatin, sodium citrate, sodium borohydride) on the structure, synthesis, and tribotechnical properties of silver nanoparticles. The mechanism of the formation and growth of silver nanoclusters was investigated using quantum-chemical calculations with full optimization of all parameters using the density functional theory (DFT) PBEPBE/Lanl2DZ method. It is shown that the use of organic stabilizers (for example, gelatin) leads to an increase in the stability of stabilized silver clusters. Such systems have greater conformational flexibility and a large number of molecular donor oxygen centres in their composition. The effect of the stabilizer on the structure of the Ag13 silver cluster was revealed in four model systems: gelatin, ammonium chloride NH4Cl, sodium borohydride NaBH4, and trisodium citrate Na3C6H5O (Na3Cit). Silver nanoparticles (AgNPs) obtained by the sonoelectrochemical, citrate, borohydride, and citrate-borohydride method varied in size from nanometers to several tens of nanometers. As a result of tribotechnical tests of lubricants with the obtained silver nanoparticles, a positive effect of stabilized silver clusters was revealed in the composition of lubricant compositions. The best tribotechnical characteristics were shown by lubricating compositions containing AgNPs stabilized with gelatin. It was found that a decrease in the size of gelatin stabilized AgNPs, when added to lubricants, leads to an increase in the tribological properties. [ABSTRACT FROM AUTHOR]