Introduction. In modern conditions, the combustibility of polymers plays a dominant role in the process of the appearance and spread of fires. This is because the extremely wide use of polymeric materials in all areas of the national economy. Due to the organic structure, the high content of carbon and hydrogen that make up the macromolecules of the polymers, they are extremely combustible. Combustion of polymers is accompanied by high temperature and flame propagation rate, as well as significant smoke generation and the release of a large number of toxic combustion products. Therefore, the search for new ways to reduce combustibility is one of the priority tasks in the creation and implementation of new polymer materials in various industries. Purpose. The aim of the work is the synthesis of fundamentally new complex compounds of transition metals, the study of their structure and properties, as well as predicting the possibility of their use to reduce the fire hazard of polymeric materials based on epoxy resins. Metods. Modern research methods are used in the work: X-ray diffraction, differential thermal and thermogravimetric analyzes, the method of quantum chemical calculations and IR spectroscopy. The ignition and self-ignition temperatures were determined by standard methods according to GOST 12.1.044-89 using metrologically certified equipment and calibrated measuring instruments. Results. By the direct interaction of the combustible organic amine pepa with inorganic salts of copper(II), a number of chelate complexes were obtained. By methods of x-ray phase analysis and IR spectroscopy, their structure was established. The results of quantum-chemical calculations of the complexation process showed that, as a result of the formation in the pepa–Cu(II) salt system, the chelate complexes [Cu(deta)H2O]SO4·H2O, [{Cu(deta)(H2O)(CO3)}2]·6H2O та [Cu(deta)(eda)]SiF6, the energy state of the chemically bonded pepa changes with respect to free molecules. In addition, the results of thermogravimetric studies and the measured ignition and self-ignition temperatures for pepa and complex compounds clearly showed that the process of bonding a combustible organic amine with a non-combustible inorganic salt into a solid complex ensures a decrease in the combustibility of nitrogen-containing hydrocarbon. All this is an extremely important prerequisite in the implementation of the complex mechanism of flame retardant action of transition metal salts. Conclusion. The results of the studies showed that complex compounds based on transition metal salts, and in particular copper(II), can be successfully used as flame retardants that can effectively reduce the fire hazard of nitrogen-containing synthetic polymers, including those based on epoxy resins.

Introduction. The development of modern technologies and the elaboration of new materials facilitates the wide use of epoxy resins for instance in industries. Particular attention deserves the various fire retardant coatings making. These coatings are increasingly used to increase fire resistance of details and designs made of metals, plastics, wood in various industrial and civil constructions, and in transport. The very perspective mode producing the effective fire retardant coatings is the direct introduction into the polymeric matrix of epoxy resins of reactive fire retardant agents. Purpose. The aim of this work is to study the effect of the elaborated fire retardant on the ability of epoxy-amine composites modified with copper(II) carbonate to resist the spread of the flame, as well as the effects of water and chemicals. Metods. The flame propagation rate on the surface of horizontally located experimental samples was determined according to all-State Standard 28157-89. Water and chemical resistance were evaluated by a gravimetric method on the polymer mass film change after exposure to distilled water and corrosive media for a certain period of time. Results. The results of experimental studies have shown that samples of the epoxy-amine composites containing 20, 40 and 80 mass parts of CuCO3 per 100 mass part of the binding agent do not propagate the flame horizontally at all. At that, duration of free combustion of these polymer samples did not exceed 2 min. It has been found too that the penetrability of water and chemicals through films based on epoxy-amine composites modified with CuCO3 is reduced due to the formation of chemical bonds between copper(II) carbonate and polyethylenepolyamine. The lowest level of the equilibrium absorption in water and 10% aqueous solutions of H2SO4 and NaOH was watched for samples of those composites that contained 20 mass parts of CuCO3 per 100 mass parts of binder. Conclusion. When studying the effect of copper(II) carbonate on the flame propagation rate, it was found that the epoxy-amine composites containing >20 mass parts of CuCO3 per 100 mass parts of the binding agent, do not propagate the flame and so these are self-extinguishing. The copper(II) carbonate addition to epoxy polymers reduces their sorption capacity in water and solutions of alkalis and acids. These data are the basis to future develop the chemically resistant fire retarding coatings based on epoxy-amine composites modified with copper(II) carbonate. Keywords

Introduction. The rapid growth of production rates and the use of polymer materials in various fields has brought about an increase in the number of fires caused by the ignition of polymer products. Among the most common polymer materials are materials based on epoxy resins. They are used in such industries as construction, electrical engineering and radio engineering, shipbuilding, mechanical engineering, including automotive, aerospace and rocketry, etc. Due to its organic structure, high content of carbon and hydrogen, epoxy polymers are very combustible. Their combustion is characterized by high temperature and more flame propagation rate. And it is accompanied by significant smoke formation and the release of large amounts of toxic products. Therefore, the search for new ways to reduce combustibility and maintain the proper level of performance is one of the priorities in the development and implementation of new epoxy polymer materials in various fields. Purpose. The work aims to obtain epoxy-amine composites and to discover the effect of flame retardant-hardener on their fire hazard and physical and mechanical properties.Methods. In work used Modern research methods. The flame propagation rate was determined by UL94, the coefficient of smoke was measured by ASTM E662-19, physical and mechanical properties were evaluated by measuring parameters such as surface hardness, tensile strength, water absorption and chemical resistance.Results. The parameters of fire danger of epoxy-amine composites with different content of flame retardant (0, 5, 16 and 80 mass parts) were studied. The results of experimental studies showed that the flame propagation rate and the smoke formation coefficient in the mode of smouldering and combustion are minimal for epoxy-amine composites containing 16 and 80 mass parts of flame retardant. Such compositions have higher surface hardness and tensile strength. And they also well as more resistant to water and aggressive environments compared to unmodified ones.Conclusion. The paper presents a simple and commercially attractive method of obtaining epoxy-amine composites con-taining different amounts of flame retardant – copper(II) sulfate. It is necessary, the obtained samples of the composites are homogeneous in structure. These should be considered as individual chemicals, not as mixtures. Chemical bonding of all components of the composites, namely the appearance of additional (compared to the unmodified composite) Cu(II)–N coordination bonds in the polymer framework DGEBA/DETA-CuSO4, is reflected in the enhanced physical and mechanical properties and fire hazard reduction for this type of composite materials.

Introduction. Inflammation susceptibility and the nature of combustion are one of the most important characteristics for the parametrization of the fire hazard of polymer materials. Because ignition is the occurrence process of the persistent flame near the surface of the material, which is preceded by the process of propagation of the flame front on its surface, the predisposition to ignition of the polymer materials plays an important role in the aspect of initiation of fires. A comparative evaluation of inflammation susceptibility of substances of different nature was carried out basing the determination of the ignition point and self-ignition point. Purpose. The work aims to determine the peculiarities of the influence of copper(II) carbonate on the increase of ignition point and self-ignition point of epoxy-amine composites. Metods. The experimental determination of the ignition point and self-ignition point was carried out according to all-Union State Standard 12.1.044-89 (4.7, 4.9 items). Toward this end, three samples of the test material were prepared with a weight of 3 g. Before testing, samples were conditioned in air. Results. Data on the effect of copper(II) carbonate on the value of ignition point and self-ignition point of the epoxy-amine composites indicate that the epoxy-amine-based composite, cured by the traditional amine hardener (PEPA), has lowest temperature of the ignition  and self-ignition. The temperture values of ignition and self-ignition increase as the content of copper(II) carbonate increases in the composite, measuring up a maximum value at 80 g of CuCO3 per 100 g of binder. It is proved that the reason for the increase of the ignition temperature and self-ignition temperature of the modified epoxy-amine composites is the appearance of strong coordination bonds that are formed due to the chemical binding of the combustible polyethylenepolyamine with the non-combustible inorganic salt (with copper(II) carbonate). The measured values of the ignition point and self-ignition point of the amine hardener (PEPA) of the epoxy-diane oligomer indicate that it is able to ignite at temperature 136ºC, and self-ignite at temperature 393ºС. After forming the chelate complex, the coordinated PEPA turns into a practically non-combustible substance. Conclusion. Consequently, the main factor that affects to make difficulty of ignition of organic nitrogen-containing substances is the efficient chemical binding N atoms of the combustible amine molecules with d-metal atom of the non-combustible inorganic salt, which is accompanied by the formation of sufficiently strong coordination bonds of the Cu(ІІ)¬N type. The resistance to ignition of the modified polymeric composites will depend on the binding strength of the copper(II) salt with an amine hardener. The mechanism of the fire retardant influence of the d-metal salts on combustion of the epoxy-amine-based composites consists in this. So, copper(II) compounds, in particular copper(II) carbonate, can successfully be used as the fire retardant additives enabling of efficiently lowering the fire hazard of synthetic polymers based on epoxy-amine composites.