Metal‐coordinated epoxy polymers with suppressed combustibility. Preparation technology, thermal degradation, and combustibility test of new epoxy‐amine polymers containing the curing agent with chelated copper(II) carbonate

Abstract

Summary The diethylenetriamine chelate complex of copper(II) carbonate—DETA‐CuCO3 (a fire retardant hardener of epoxy resins)—and the CuCO3‐containing epoxy‐amine polymers—DGEBA/DETA‐CuCO3(6), DGEBA/DETA‐CuCO3(12), DGEBA/DETA‐CuCO3(40), and DGEBA/DETA‐CuCO3(80) with suppressed combustibility—have been obtained in the DETA‐DGEBA‐CuCO3 system (DETA and DGEBA are diethylenetriamine and bisphenol A diglycidyl ether, respectively). The DETA‐CuCO3 chelate complex was characterized by X‐ray powder diffraction, infrared spectra, and thermal analysis. The thermal gravimetric analysis results have revealed that thermal destruction of DETA‐CuCO3 was finished at 400°С, and the maximal temperature of the combustion gases amounted to 520°С. The thermal behavior and combustibility of the CuCO3‐containing epoxy‐amine polymers were studied using thermal analysis and “Ceramic tube” (CT) method. Thermal gravimetric analysis confirms that incorporation of the DETA‐CuCO3 into DGEBA appreciably heightens the thermal stability and antiflammability of the CuCO3‐containing epoxy‐amine polymers. Results of CT measurement reveal that maximal temperature of the combustion gases under burning of the DGEBA/DETA‐CuCO3(12) sample in comparison with unmodified epoxy‐amine polymer (DGEBA/DETA) is lowered on 219°С and the loss of weight is decreased on 20.5 wt%. According to ASTM 635‐14, ASTM D2863‐13, and ASTM D1929‐16, the flame propagation rate, limiting oxygen index, and temperatures of ignition and self‐ignition have been measured for the elaborated polymer samples.

Study of the composition of humic acids of different origins

“…Thermal analysis is one of the important methods to study organic compounds. It allows investigating not only the thermal stability of substances, but also the nature of the processes that occur when they are heated [9,10].…”

New copper(II)‐coordinated epoxy‐amine polymers with flame‐self‐extinguishment properties: Elaboration, combustibility testing, and flame propagation rate measuring

“…Combustibility parameters were determined for samples of DGEBA/pepa ‐CuSiF 6 (I), DGEBA/pepa ‐CuSiF 6 (II), DGEBA/pepa ‐CuSiF 6 (III), and DGEBA/pepa ‐CuSiF 6 (IV), as well as DGEBA/pepa (for comparison) according to all‐Union State Standard 12.1.044‐89 (Supporting Information), which is described in detail in, 15 using the “Ceramic tube” (CT) apparatus. The results of the CT measurements are presented in Table 3.…”

“…Said studies were started relatively recently and those are currently developing rapidly. Already the first tests carried out in this area revealed a high fire‐retardant ability of substances of this type 12‐16 . In particular, it was found that epoxy resins cured by amine complexes of d ‐metals have higher ignition and self‐ignition temperatures, spread flame more slowly and are characterized by lower values of the maximum temperature of gaseous products of combustion and smoke formation in comparison with the known epoxides cured by traditional amine hardeners.…”

The Effect of Preparation Technology and the Complexing on the Service Properties of Self-extinguishing Copper(II) Coordinated Epoxy-amine Composites for Pouring Polymer Floors

“…The combustibility parameters for the DGEBA/PEPA, DGEBA/PEPA-CuSO4, (DGEBA/PEPA)2-(CuOH)2CO3 and DGEBA/PEPA-CuSiF6 composites were determined according to all-Union State Standard 12.1.044-89 using the ceramic tube (CT) method, which is described in detail in (Lavrenyuk et al, 2018b). Its gist consists of temperature conditions that promote polymer material combustion.…”

“…) Unlike organic salts, inorganic salts are non-combustible. That is why our work developing epoxy-amine composites Lavrenyuk et al, 2016а;Lavrenyuk et al, 2018a;Lavrenyuk et al, 2018b) has used chelate complexes composed of exclusively inorganic salts from copper(II) and polyethylenepolyamine (PEPA).…”