Materials Science Forum Vol. 1006

Abstract: Determination of characteristic of fireproof capability of examined fire-retardant coating by experiment-calculated method solving the inverse heat conduction problems based on the firing tests data. With the aim of determining the fire-resistance time of metal sheets with fire-retardant coating there are used experimental research methods of patterns behavior during heating according to the requirements of National Standards of Ukraine B.V. 1.1.-4-98 are used; mathematical and computer modelling of processes of unsteady heat transfer in the system “metal sheet – fire-retardant coating”; determination of thermal characteristics and characteristic of coating fireproof capability. Firing tests of metal sheets covered by the flame retardant “Amotherm Steel Wb” are carried out. Based on the obtained data (temperature from the unheated sheet surface) there are determined the thermal characteristics of formed coating depending on temperature and the characteristic of fireproof capability of examined coating for 30 minutes fire-resistance time. The effectiveness of intumescent coating “Amotherm Steel Wb” is proved and the dependence between its heat conduction coefficient and temperature during heating in experimental stove of metal sheet with this coating in standard temperature conditions is specified. The co-relation between the thickness of intumescent coating “Amotherm Steel Wb” and fire-retarding quality of metal constructions is identified. Besides the necessary minimum thicknesses of such coating from the thickness of metal sheet for importance of 30 minutes fire-resistance time are calculated.

Abstract: The main problem with creating compressed air systems is to properly regulate the flow of water and the flow of air that is fed into the mixing chamber so as to continuously provide a foam that must have adequate fire-fighting properties and remain stable over time. The process of obtaining compression foam is a thermodynamic process, which depending on the specified technological factors can be both isothermal and adiabatic. The nature of the process determines both the geometric and physical properties of the foam, and its possible fluctuations can lead to changes in the physical characteristics of the foam. The work provides recommendations for determining the type of thermodynamic process, which makes it possible to improve the accuracy when creating mathematical models of mobile plants for the production of CAF.

Abstract: The aim of the work was to determination the combustibility group of color fire retardant paints for wood. As a result of the fire tests, it was found that the developed compositions of fire-retardant mineral paints on an alkaline aluminosilicate binder in the (Na, K)₂O-Al₂O₃-nSiO₂-mH₂O system are difficult to combustible and to flammable, and occupy a middle position between G1 and G2 in the combustibility group. As a result of the fire tests, the temperature of the flue gases did not exceed the critical value - above 260 [°C], the weight loss of the samples was in the range from 5.56 to 10.17 [%], and the burning rate did not exceed 0.0026 [kg/(m²s)]. Given the rather high margin of flue gas temperature, further fire tests are planned to be carried out according to EN 13823 in RICE Sweden.

Abstract: The influence of the degree of homogeneity of the SiO₂ sol on the duration of the induction period and the quality of fire-resistant coatings on textile materials was studied. The prospects of using IR spectroscopy as an express method for studying the phase composition of a gel coating, the degree of completion of the hydrolysis of an organosilicon component, and adjusting the parameters for obtaining a high-quality fire-resistant binary coating of a sol SiO₂ - flame retardant system are shown.

Abstract: The effect of the composition on the weight loss of wood protected by a coating based on inorganic and organic substances in the process of thermal exposure, which is a feature of the study of the flame retardant effectiveness of the composition, is investigated. The solution of this problem is carried out by specially developed methods. The influence of fire protection under the influence of high-temperature heat flux on the change in the process of loss of mass of fire-protected wood is determined and the mechanism of kinetics of action of the composition is characterized, which is characterized by a decrease in the speed of flame propagation and mass loss. The results of thermogravimetric studies determined the weight loss of the coatings as a function of temperature, the results of which investigated the activation energy at the temperature decomposition of the coatings and found that for wood it was 36.56 kJ / mol, and in the case of fire protection it increased 2.3 times. which makes it possible to conclude that it is advisable to use lacquer varnish to improve the fire retardant efficiency of wood. Thus, for the specimen of fire-retardant lacquer wood, there is a gradual decrease in temperature, ie, the work of the coating is fixed, and, accordingly, the activation energy is increased during the decomposition of the wood. In order to establish the flame retardant efficiency in the application of high-temperature blowing lacquer, studies were conducted to determine the combustibility index of wood by mass loss, flame spread and temperature increase of flue gases and found that when processing wood goes to the group of combustible materials with a burning index.

Abstract: The possibility of using polymers based on epoxyphenolic binders to obtain fiberglass with an intense level of carbonization has been investigated. The correlation between the pyrolytic transformations intensity and the fire hazard indicators of polymers is shown. It is established that the conditions for the intensive passage of pyrolytic reactions are facilitated by the presence in the matrix system of conjugated aromatic (naphthalene) radicals. The C/H ratio in the carbonized layer is confirmed by the data of IR spectroscopy both at the preparation stage and after exposure to characteristic temperatures.

Abstract: The problems of reducing combustibility and increasing fire resistance of some polymer building materials are considered. And the toxicity of the gaseous products of their thermal degradation was evaluated both individually and in various combinations with each other. The features of thermal degradation and the loss of mechanical properties under the influence of a flame of polymer building materials were studied. The following samples were used: water pipes based on polyethylene; Tarkett linoleum, Ondex roofing products, Rolvaplast PVC profile panels; structural panels of the company "Polygal"; facing tile based on phenol-formaldehyde oligomers. The processes occurring during pyrolysis and combustion are considered, the results of a study of the combustibility and mechanical properties of polymer building materials based on polyethylene, polyvinyl chloride, polycarbonate, phenol-formaldehyde and epoxy oligomers under the influence of a flame are presented. For the studied building polymer materials, the products of pyrolysis and combustion were studied; their ignition and self-ignition temperatures, and also the flame propagation velocity were measured. The data on the toxicity of the products of their combustion, both individually and under combined action, are summarized. Also, for the studied polymer building materials, the losses of heat resistance, toughness, and flexural strength under the influence of a flame were studied. Thermogravimetric analysis of Rolvaplast PVC panels and Poligal polycarbonate panels allowed us to determine the maximum temperatures and activation energies of the polymer decomposition process. It was concluded that if the material is recognized as non-combustible or slow-burning, it will not always be fire resistant, since its strength and thermal properties can sharply decrease already in the first seconds of flame exposure.

Abstract: Effect of content of synthetic aluminosilicates in medium-density polyethylene on the fire hazard characteristics and mechanical properties of compositions is investigated. It has been shown that during decomposition of the filler with the release of water, its effectiveness depends not only on the endothermic effect of decomposition and the content of dehydration products, but also on the correspondence of temperature of the dehydration of the filler and the temperature of intensive decomposition of the polymer. Regardless of the type of fillers, an increase in their content in polymer composite material helps to reduce combustibility. It has been shown that compositions based on epoxy oligomers or medium-density polyethylene and synthetic zeolite have properties of self-extinguish and fairly high physical and mechanical characteristics. It is shown that epoxy polymer composite material with the content of inorganic fillers 40-70 wt.% can be used for sealing building structures and other products operating at elevated temperatures, as well as in a mode where the fire resistance and heat resistance of the sealing compound are decisive. A number of efficiency of flame-suppressing of fillers is presented. Formulations of compositions based on epoxy oligomers or medium-density polyethylene whith synthetic zeolite having an optimal ratio of fire hazard and mechanical properties and not having toxic or carcinogenic effects when heated are recommended.

Abstract: To extinguish alcohols, it is proposed to use a two-layer material consisting of a layer of a light porous carrier, on which an insulating gel layer is applied. The use of crushed foam glass as a porous carrier is justified. To obtain an insulating layer of gel, it is proposed to use a gel-forming system CaCl₂ + Na₂ O · 2.7 SiO₂ . The insulating and cooling properties with respect to the alcohols of two separate layers and the buoyancy of a crushed foam glass layer are determined. The cooling properties of the two-layer foam glass - gel material were evaluated. To increase the cooling properties of the foam glass, it is proposed to wet it. It was found that, at the same time as the cooling effect increases, wetting of the foam glass leads to a decrease in its buoyancy and insulating properties with respect to alcohol vapors. The heights of dry and wetted foam glass layers necessary to stop the combustion of one, two, and three atomic alcohols were experimentally determined. It is concluded that alcohols can be quenched with dry and moistened foam glass, both with a gel layer applied to its surface and without a gel layer.