Рассмотрено влияние содержания и химической природы исходных компонентов на термостойкость, воспламеняемость и дымообразующую способность композиционных материалов на основе эпоксидных олигомеров. Установлено, что фосфатные пластификаторы практически не влияют на горючесть эпоксидных полимеров, но снижают их дымообразующую способность. Показано, что при содержании минеральных наполнителей менее 45 % масс. их химическая природа мало влияет на воспламеняемость эпоксидных композитов, а коэффициент дымообразования линейно уменьшается с ростом степени наполнения. Для снижения горючести эпоксидных композитов предложено использовать аддитивные бромсодержащие антипирены в виде раствора в N,N-диметил-2,4,6-триброманилине. Показана высокая эффективность ацетилферроцена и a-оксиэтилферроцена, используемых в качестве дымоподавителей эпоксидных композитов. Выявлена корреляция кислородного индекса с предельной концентрацией кислорода и критической плотностью теплового потока воспламенения композитов.
Introduction. Epoxy oligomers are widely used as binders in construction industry. At the same time, wide use of polymers in modern construction industry requires careful examination and optimization of operational properties related to fire safety. It is known that such properties can be controlled by chlorinated paraffins, synthesized fire retardants of type “Redant” and many other compounds. However, the effect of such compounds to the properties of epoxy matrix composites has not been thoroughly investigated to date. The choice of an admixture that reduces the fume evolution of epoxy composites is an important task also. Purpose of the work. The purpose of this work is to study the thermal stability, flammability, fume evolution of epoxy matrix composites with different types and amounts of hardeners, fillers, plasticizers, fire retardants and ferrocene derivatives. Materials and methods. Dependencies between thermal stability, flammability, fume evolution of polymer matrix composites based on ED-20 epoxy resin and amount and chemical type of components are examined in the present work. To control operational properties of interest the chemical type and content of hardeners, fillers, plasticizers, fire retardants and ferrocene derivatives are varied. DuPont-9900 device is used for thermal analysis. Properties related to fire safety are determined in accordance with RU GOST 12.1.044-89 and several methods that were previously developed by authors of this work. Results. It is shown that while phosphate-based plasticizers are of almost no effect on combustibility of epoxy-based polymer matrix composites, they can successfully be used for the reduction of fume evolution. It is revealed that chemical nature of mineral fillers has little effect on the flammability when amount of such fillers are less than 45 % by weight; at the same time, fume evolution linearly decreases with the increase of degree of filling. To reduce the flammability of epoxy composites, we propose additive bromine-containing flame retardants in the form of a solution in N,N-dimethyl-2,4,6-tribromoaniline. High efficiency of acetylferrocene and a-hydroxyethylferrocene as reducers of fume evolution is shown. The correlation between critical density of the heat flux of ignition and limiting oxygen index and also limiting concentration of oxygen is revealed. Conclusion. In the present work we have summarized results of several laboratory tests. The tests were allowed to select the type and amount of components of epoxy matrix composites with improved operational properties, intermediate and small combustibility. Such composites can successfully be used in different areas of construction industry.
The authors declare that there are no conflicts of interest present.