FEATURES OF THE COPPER(II) CARBONATE INFLUENCE ON AN INFLAMMABILITY OF EPOXY-AMINE COMPOSITES

Fire Safety ◽  
2018 ◽  
pp. 73-78
Author(s):  
P. Pastuhov ◽  
O. Lavrenyuk ◽  
B. Mykhalitchko ◽  
V. Petrovskii

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.

Author(s):  
Valeriy V. Belozerov

Introduction. The article provides an overview of the existing approaches to solving the problem of combustion of substances and materials, for their adequacy in determining their fire hazard of products and objects. The relevance of the work is due to the need to move from latent forms in determining the fire hazard of materials and products made from them (degrees of fire resistance, flammability groups, groups of the effectiveness of fire retardant coatings, etc.) to analytical forms describing the processes in the combustion theory. Problem statement. The task of the research is to determine the relationship between the theory of combustion of substances and materials and to assess their fire hazard in natural and man-made systems. Theoretical part. The system analysis of solutions to the combustion theory problems is performed. Its results became the basis of probabilistic-physical and entropy approaches, as well as proposals for changing standards designed to provide protection from fires. Conclusions. The results of the study showed the need to revise empirical approaches in assessing the fire hazard of materials and products made from them, which includes using thermoanalytic and acoustic methods and means.


Fire Safety ◽  
2021 ◽  
Vol 38 ◽  
pp. 18-23
Author(s):  
P. Pastuhov ◽  
V. Petrovskii ◽  
O. Lavrenyuk ◽  
B. Mykhalitchko

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.


2016 ◽  
Vol 16 (3) ◽  
pp. 643-661 ◽  
Author(s):  
Kostas Kalabokidis ◽  
Alan Ager ◽  
Mark Finney ◽  
Nikos Athanasis ◽  
Palaiologos Palaiologou ◽  
...  

Abstract. We describe a Web-GIS wildfire prevention and management platform (AEGIS) developed as an integrated and easy-to-use decision support tool to manage wildland fire hazards in Greece (http://aegis.aegean.gr). The AEGIS platform assists with early fire warning, fire planning, fire control and coordination of firefighting forces by providing online access to information that is essential for wildfire management. The system uses a number of spatial and non-spatial data sources to support key system functionalities. Land use/land cover maps were produced by combining field inventory data with high-resolution multispectral satellite images (RapidEye). These data support wildfire simulation tools that allow the users to examine potential fire behavior and hazard with the Minimum Travel Time fire spread algorithm. End-users provide a minimum number of inputs such as fire duration, ignition point and weather information to conduct a fire simulation. AEGIS offers three types of simulations, i.e., single-fire propagation, point-scale calculation of potential fire behavior, and burn probability analysis, similar to the FlamMap fire behavior modeling software. Artificial neural networks (ANNs) were utilized for wildfire ignition risk assessment based on various parameters, training methods, activation functions, pre-processing methods and network structures. The combination of ANNs and expected burned area maps are used to generate integrated output map of fire hazard prediction. The system also incorporates weather information obtained from remote automatic weather stations and weather forecast maps. The system and associated computation algorithms leverage parallel processing techniques (i.e., High Performance Computing and Cloud Computing) that ensure computational power required for real-time application. All AEGIS functionalities are accessible to authorized end-users through a web-based graphical user interface. An innovative smartphone application, AEGIS App, also provides mobile access to the web-based version of the system.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3979
Author(s):  
Anna Strąkowska ◽  
Sylwia Członka ◽  
Karolina Miedzińska ◽  
Krzysztof Strzelec

The subject of the research was the production of silsesquioxane modified rigid polyurethane (PUR) foams (POSS-Cl) with chlorine functional groups (chlorobenzyl, chloropropyl, chlorobenzylethyl) characterized by reduced flammability. The foams were prepared in a one-step additive polymerization reaction of isocyanates with polyols, and the POSS modifier was added to the reaction system in an amount of 2 wt.% polyol. The influence of POSS was analyzed by performing a series of tests, such as determination of the kinetics of foam growth, determination of apparent density, and structure analysis. Compressive strength, three-point bending strength, hardness, and shape stability at reduced and elevated temperatures were tested, and the hydrophobicity of the surface was determined. The most important measurement was the determination of the thermal stability (TGA) and the flammability of the modified systems using a cone calorimeter. The obtained results, after comparing with the results for unmodified foam, showed a large influence of POSS modifiers on the functional properties, especially thermal and fire-retardant, of the obtained PUR-POSS-Cl systems.


2020 ◽  
Vol 1006 ◽  
pp. 93-100
Author(s):  
Vadym Nizhnyk ◽  
Yurii Feshchuk ◽  
Volodymyr Borovykov

Based on analysis of appropriate literary sources we established that estimation of fire separation distances was based of two criteria: heat flux and temperature. We proposed to use “ignition temperature of materials” as principal criterion when determining fire separation distances between adjacent construction facilities. Based on the results derived while performing complete factorial we created mathematical model to describe trend of changing fire separation distances depending on caloric power of fire load (Q), openings factor of the external enclosing structures (k) and duration of irradiation (t); moreover, its adequacy was confirmed. Based on linear regression equations we substantiated calculation and tabular method for the determination of fire separation distances for a facility being irradiated which contains combustible or otherwise non-combustible façade and a facility where liquid oil products turn. We developed and proposed general methodology for estimation of fire separation distances between construction facilities by calculation.


2015 ◽  
Vol 1129 ◽  
pp. 151-158
Author(s):  
Takako Tokura ◽  
Joyce Lim ◽  
Ai Ming Chua ◽  
Wey Liang Lee ◽  
James Wong

Polymers are commonly used in concrete materials. The type and concentration of polymer are important information for stakeholders, because they have a critical impact on the properties of concrete materials. Therefore, reliable and accurate information is highly desirable. To this end, Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA) are used to analyze polymer contents in construction materials.FTIR spectroscopy is a suitable technique to identify the polymer type using IR spectrum matching. Additionally, functional group information can be easily obtained from each peak. Attenuated Total Reflection (ATR) method can be used to measure extracted polymers from construction materials to obtain IR spectra, and match against the library database to identify the polymer materials. TGA is one of the common thermal analysis methods. It measures the weight loss or gain of sample due to chemical reactions such as vaporization, decomposition and oxidation as a function of temperature. In this paper, we will discuss development of reliable analytical methods with which mixtures of polymer, fine aggregate and cement with different percentages of polymer content were prepared and evaluated.


Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1333 ◽  
Author(s):  
Adrián Rodríguez-Panes ◽  
Juan Claver ◽  
Ana Camacho

This paper presents a comparative study of the tensile mechanical behaviour of pieces produced using the Fused Deposition Modelling (FDM) additive manufacturing technique with respect to the two types of thermoplastic material most widely used in this technique: polylactide (PLA) and acrylonitrile butadiene styrene (ABS). The aim of this study is to compare the effect of layer height, infill density, and layer orientation on the mechanical performance of PLA and ABS test specimens. The variables under study here are tensile yield stress, tensile strength, nominal strain at break, and modulus of elasticity. The results obtained with ABS show a lower variability than those obtained with PLA. In general, the infill percentage is the manufacturing parameter of greatest influence on the results, although the effect is more noticeable in PLA than in ABS. The test specimens manufactured using PLA perform more rigidly and they are found to have greater tensile strength than ABS. The bond between layers in PLA turns out to be extremely strong and is, therefore, highly suitable for use in additive technologies. The methodology proposed is a reference of interest in studies involving the determination of mechanical properties of polymer materials manufactured using these technologies.


2013 ◽  
Vol 838-841 ◽  
pp. 14-17
Author(s):  
Ivana Turekova ◽  
Zuzana Szabova ◽  
Tomas Chrebet ◽  
Jozef Harangozo

The paper reports a study of the impact of moisture and age of pellets, as well as an external condition, on the thermal degradation of the thermoplastic polyurethane elastomers. Because thermoplastic polyurethane elastomers are hydroscopic polymer, moisture will have a significant impact on thermal degradation. For determination of the effect of moisture and age were used the thermo gravimetric analysis, differential scanning calorimeter and ISO STN 871: Plastics. Determination of ignition temperature using a hot-air furnace.


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