Bakary Tamboura

INTRODUCTION/OBJECTIVE: Healthcare-associated infections (HAIs) represent a major challenge in medical facilities, necessitating the development of self-disinfecting surfaces. This study investigates the performance of a newly synthesized compound, hexa[( pyridin-4-yl)amino]cyclotriphosphazene (HPP), as a promising modifier for acrylic coatings aimed at reducing microbial surface contamination. METHODS: HPP was synthesized by grafting six pyridinamine groups onto a hexachlorocyclotriphosphazene core. Its structure was confirmed by NMR spectroscopy and MALDI-TOF mass spectrometry. The potential of HPP as an antimicrobial modifier was evaluated using computational modeling (the SwissADME platform for QSPR/QSAR predictions). Coating compositions were prepared by incorporating HPP (0-5 wt%) into a fast-drying, water-based acrylic paint (Elcon brand). Physicochemical properties (adhesion, water absorption, chemical resistance, abrasion resistance, and UV-aging resistance) and antimicrobial activity against Escherichia coli and Candida albicans were assessed according to ISO standards. RESULTS: HPP is a nanoscale molecule (diameter ~1.25 nm) with a high molecular weight (693.58 g/mol), low water solubility (Log S = -7.31), and moderate lipophilicity (Consensus Log P = 2.94). Compared to unmodified samples, coatings containing HPP demonstrated improved adhesion (score 0 on concrete starting from 1 wt% and on wood starting from 3 wt%), reduced water absorption, increased abrasion resistance, and good chemical resistance to NaOH and H2O2. Antimicrobial activity reached 18.9% inhibition for E. coli and 41.9% for C. albicans at 5 wt% HPP. DISCUSSION: The predicted low systemic absorption and low skin permeability (Log Kp = -6.69 cm/s) confirm the safety profile of HPP for use in coating formulations. The absence of PAINS alerts indicates stability, while the nanoscale size favors immobilization within the polymer matrix, explaining the improved physicochemical properties and sustained antimicrobial activity. CONCLUSION: HPP is an effective multifunctional additive for acrylic paints intended for healthcare settings. The resulting modified paint is suitable for application in facilities where a reduction in microbial surface contamination is required.

This review analyzes the advances over a five-year period in the development of polymeric sorbents for the purification of aqueous media from key classes of pollutants: hydrocarbons (crude oil, diesel fuel), organic dyes, pharmaceuticals (antibiotics), pesticides, herbicides, volatile organic compounds, and polycyclic aromatic hydrocarbons. Attention is paid to the analysis of structure-property-performance relationships, with an emphasis on comparing materials derived from renewable natural feedstocks (such as cellulose, chitosan, terpenes, vegetable oils, and aloe vera) with synthetic polymers. The analysis reveals that biopolymer-based sorbents exhibit comparable or superior sorption capacities combined with environmental safety, biodegradability, and low cost. The key sorption mechanisms include physical adsorption, hydrophobic interactions, and electrostatic interactions. Despite persisting challenges related to scalability, stability in real-world environments, and the need for efficient regeneration protocols, a convergent approach that combines the advantages of modified natural polymers and functional synthetic components appears to be the most promising strategy for developing cost-effective and sustainable technologies for the restoration of water quality.

The development of dental restorative materials with improved physical and mechanical properties is an important area of research. In this study, hexaallylaminocyclotriphosphazene (HAP) was used to modify dental composites. HAP is a compound with multiple carbon-carbon bonds that can react with methacrylic resins to form a copolymer. HAP was synthesized by reacting allylamine with hexachlorocyclotriphosphazene and characterized it using 1H and 31P NMR spectroscopy and MALDI-TOF mass spectrometry. Molecular dynamics simulations using the MM2 force field showed that HAP has a nanosize (the diameter of a sphere eclosing the molecule is 1.3 nm), making it a suitable nanomodifier for dental composites. Using 3D printing, samples of dental methacrylic composites containing up to 10 wt. % HAP were prepared and their physicomechanical properties and antibacterial activity against gram-positive bacteria S. mutans were studied. As a result, it was established that the maximum flexural strength (115.1 ± 10.2 MPa) is achieved with a modifier content of 5 wt.% in the composite. The maximum value of inhibition of S. mutans growth in a liquid nutrient medium is achieved with a HAP content of 10 wt.% in the sample. Furthermore, with a HAP content of more than 5 wt.% in the composite, inhibition of biofilm on the material surface is observed. The resulting composite is proposed for use as dental crowns in restorative dentistry.

This review examines the fire-retardant properties of compositions that incorporate various classes of phosphorus–nitrogen compounds. Specifically, it focuses on nitrogen-containing derivatives of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, phosphinates, phosphorus–nitrogen salts, and aryloxycyclophosphazenes. The findings indicate that these classes of fire retardants enhance the limiting oxygen index, decrease heat and smoke emission indices in epoxy compositions, and facilitate the creation of self-extinguishing materials. Notably, aryloxycyclophosphazenes with reactive functional groups emerge as the most effective fire retardants, particularly in terms of their impact on the mechanical properties of epoxy compositions and compatibility with epoxy resin. This review would be a valuable resource for engineers, chemical engineers, materials scientists, and researchers engaged in the development of non-combustible polymer composites and organoelement compounds.

работа посвящена способу получения изофорона в микроканале. Проведена численная и экспериментальная оптимизация процесса получения изофорона в микроканале. Изофорон – ненасыщенный циклический кетон, широко использующийся в промышленности в качестве растворителя нитроцеллюлозных красок, а также в качестве промежуточного вещества для синтеза других соединений. Синтез проводили в микроканалах. Микроканалы представляют из себя каналы диаметром меньше 1 мм. Их основная особенность – возможность проведения различных типов реакций, требующих высокие давления и температуры. За счёт небольшого внутреннего объёма, все процессы, протекающие в них, легко интенсифицируются, можно достигать высокой точности и эффективности эксперимента. Варьировались такие параметры, как температура реакции и расход реагентов. Использовался новый подход к проведению эксперимента, основанный на минимизации используемых параметров регулирования и правильному их комбинированию. Такой подход требует высокой точности и воспроизводимости результатов, поэтому лучшим выбором для таких задач являются микроканалы, используемые в данной работе. Разработана математическая модель реакции, основанная на системах уравнений разной сложности. Построены трехмерные и двухмерные контурные диаграммы, позволяющие визуализировать математическую модель процесса. Установлены наилучшие технологические параметры процесса. the work is devoted to the method of obtaining isophorone in a microchannel. Numerical and experimental optimization of the process of obtaining isophorone in a microchannel has been carried out. Isophorone is an unsaturated cyclic ketone, widely used in industry as a solvent for nitrocellulose paints, as well as as an intermediate for the synthesis of other compounds. The synthesis was carried out in microchannels. Microchannels are channels with a diameter of less than 1 mm. Their main feature is the possibility of carrying out various types of reactions requiring high pressures and temperatures. Due to the small internal volume, all processes occurring in them are easily intensified, high accuracy and efficiency of the experiment can be achieved. Parameters such as reaction temperature and reagent consumption varied. A new approach to conducting the experiment was used, based on minimizing the control parameters used and combining them correctly. This approach requires high accuracy and reproducibility of the results, so the microchannels used in this work are the best choice for such tasks. A mathematical model of the reaction based on systems of equations of varying complexity has been developed. Three-dimensional and two-dimensional contour diagrams are constructed to visualize the mathematical model of the process. The best technological parameters of the process have been established.

ABSTRACT: Introduction. In connection with the growing demand for living and working conditions in civil and industrial construction, there is an increasing need for high-quality building materials with the required set of performance properties. Polymer reinforced composite materials are promising materials in the construction industry due to their high strength, durability, reliability and economy. Polymers such as polyvinyl chloride, polyurethanes, polyacrylates, epoxy resins, polypropylene are used in construction for the manufacture of decorative elements, self-leveling floors, coatings for appliances and equipment. However, the use of polymeric materials creates risks of electric shock due to the generation of static charge. The use of electrically conductive nanomaterials as fillers makes it possible to reduce the resistivity of polymeric materials and slow down the flow of electric charges. Main part. This review article presents the benefits and drawbacks of antistatic additives for polymer materials used in industry and in the construction industry. Conclusion. An analysis of the literature has shown that over the past seven years, the largest number of relevant papers has been devoted to carbon materials as antistatic additives (8 articles), metal and metal oxide nanoparticles (7 articles), ionic liquids (7 articles), and polyaniline (7 articles). The most studied characteristics of antistatic polymer materials are the specific surface RS and volume RV resistances. According to the reviewed articles, metal and metal oxide nanoparticles are the most suitable antistatic additives to polymeric materials, since they are well dispersed in the polymer matrix. However, further research is needed to eliminate the negative effect of nanoparticles on the mechanical properties of polymeric materials