Obtaining metal-polymer nanocomposites by thermolysis of calcium salts with unsaturated mono- and dicarboxylic acids

Interest in metal-polymer nanocomposites is due to a unique combination of attractive physicochemical properties of nanosized metals, metal oxides or metal chalcogenides with mechanical, film-forming and other characteristics of polymers. This allows using them as magnetic materials for recording and storing information, catalysts, semiconductor materials, in medicine, etc. In addition, various metal-polymer nanocomposites have recently been synthesized and studied for their use as sensor materials. In this work, new and modified known methods for the synthesis of a wide range of calcium salts with unsaturated mono- and dicarboxylic acids (acrylic, cinnamic, maleic, itaconic, fumaric, trans,trans-muconic, propargyl, acetylenedicarboxylic, 4-pentynoic acids) are developed. The composition and structure of the obtained compounds were studied using elemental analysis, IR spectroscopy, X-ray phase and X-ray structural analysis. Thermal properties of salts in the solid phase were studied and main areas of temperature transformations were identified using DSC, DTA, TGA and mass spectral analysis. Kinetic regularities and mechanism of thermal transformations of unsaturated calcium carboxylates under isothermal conditions with continuous removal of gaseous decomposition products were investigated. The synthesized salts were used as single-molecular precursors for obtaining metal-polymer nanocomposites by the method of conjugate thermolysis. Particular attention was paid to the composition of solid-phase products of conjugate thermolysis. The influence of the nature of calcium-containing monomers and thermolysis conditions on the composition and structure of the resulting non-functionalized nanoparticles and metal-polymer nanocomposites with the core-shell structure was studied. Kinetic schemes and reactions of thermal transformation of calcium carboxylates were analyzed. The composition and structure of the obtained nanoparticles and metal-polymer nanocomposites were studied using elemental analysis, X-ray phase analysis, scanning and transmission electron microscopy, atomic force microscopy, sedimentation analysis, IR and Raman spectroscopy. Methods were developed for applying films based on the synthesized nanocomposites onto Corning glass substrates and substrates with interdigitated electrodes (IDE) using spin coating (SC), immersion coating (DC) and chemical vapor deposition (CVD) technologies to obtain homogeneous thin films. The physical parameters of the films and their sensor properties (speed, detection limit, range of detectable contents, selectivity, long-term stability and calibration, sensor response and recovery time, reproducibility, interfering effects, such as the effect of CO₂, temperature and humidity) were studied.

Tatiana S. Kolesnikova is a Assistant Professor and Researcher at the Department of Analytical Chemistry at the Southern Federal University in Rostov-on-Don. After completing her postgraduate studies at the Faculty of Chemistry in 2016, she is a lecturer in the Analytical Chemistry discipline at the department of the same name. She is currently engaged in obtaining and studying the possibilities of analytical application of new functional materials.