Abstract:Comparative studies of the thermal characteristics of aromatic fibres (Arselon, Arselon-S, Fenilon, Armos, Arimid PM) in air and nitrogen medium were conducted with TGA and DTA. TGA and DTA showed that the heterocyclic fibers Arimid PM and Armos have the highest thermal stability in air and nitrogen medium and Arselon and Arselon-S fibres are slightly inferior to them, but they in turn have much higher thermal characteristics than Fenilon. In nitrogen medium, all of the investigated aromatic fibres form coke r… Show more
“…This is possibly because a complicated set of chemical transformations was caused by exposure to high temperatures, which are a function of the environment. Thermooxidative processes take place in oxidizing medium (in air), thermal degradation predominant in neutral medium (in nitrogen or a vacuum), whereas pyrolysis takes place as high temperatures in neutral medium with formation of coke residue 61. Among the various polymers, those based on D , L ‐phenylalanine display the highest thermal stability due to special structure.…”
“…This is possibly because a complicated set of chemical transformations was caused by exposure to high temperatures, which are a function of the environment. Thermooxidative processes take place in oxidizing medium (in air), thermal degradation predominant in neutral medium (in nitrogen or a vacuum), whereas pyrolysis takes place as high temperatures in neutral medium with formation of coke residue 61. Among the various polymers, those based on D , L ‐phenylalanine display the highest thermal stability due to special structure.…”
“…For a detailed evaluation of the thermal characteristics of POD fibres, they were investigated by methods of thermomechanical analysis (TMA), dynamic thermogravimetry (TGA), differential scanning calorimetry (DSC), and differential thermal analysis (DTA) in air and in nitrogen medium [14][15][16], and preservation of their mechanical properties was investigated in a wide temperature range. The results of our studies corresponding to the data in [1,4,6,7] and are examined in detail below.…”
Section: Thermal Properties Of Polyoxazole Fibres and Filamentsmentioning
confidence: 99%
“…Comparative studies of POD fibres and filaments by TGA and DSC in air and in nitrogen medium indicate that in inert medium, their heat resistance increases due to exclusion of thermooxidative processes [15].…”
Section: Thermal Properties Of Polyoxazole Fibres and Filamentsmentioning
Highly heat-resistant fibres and materials made from them are widely used in different industrial sectors -for filtration of gaseous media, heat insulation, vehicle upholstery, occupational and environmental protection. Due to the high heat and thermooxidative resistance, the temperature of use of these materials is 250-300°C, attaining 300-350°C and higher for individual types, and the initial decomposition temperature is within the limits of 450-500°C.Polyoxadiazole (POD) fibres are of great interest among highly heat-resistant fibres. Professor G. I. Kudryavtsev and his colleagues (A. V. Volokhina, V. N. Odnoradova, A. V. Semenova, and others) took the initiative for manufacturing them in Russia and developing the industrial principles. Polyoxadiazole fibres and filaments of the first generation were made from the copolymer of terephthalic and isophthalic acids (in the ratio of 7:3) and hydrazine sulfate [1-5]. These fibres and filaments have the brand name Oxalone®. The initial raw materials are phthalic acids and hydrazine sulfate -readily available and manufactured in many countries in the world.At present, Heat-Resistant Articles Production Co. is the leading firm in POD fibre and filament technology; together with Svetlogorsk Khimvolokno Production Association, it developed new continuous technology for manufacturing them from terephthalic acid homopolymer and hydrazine in equimolar ratios and organized their industrial production. The trade name "Arselon" was registered for the second generation of POD fibres and filaments [6][7][8]. Heat-resistant photostabilized fibres and filaments were also developed.
“…It is very important to recognize the properties of PBIA fiber, which significantly influence the heat treatment processes and application conditions. Studies on the thermal properties have been paid great attention over the past years [5], but understanding a detailed analysis of the thermal degradation and mechanism of PBIA fiber is little concentrated on.…”
The properties of the fiber material, which prepared from the high-performance heterocyclic polymer poly-p-phenylene-benzimidazole-terephthalamide (PBIA), were investigated. Poly-m-phenylene isophthalamide (PMIA) and poly-p-phenylene terephthalamide (PPTA) fibers were also studied, for comparison, under the same experimental conditions. Thermogravimetry(TG) and thermogravimetry coupled to Fourier transform infrared spectroscopy(TG-FTIR) were used to study the properties of these fibers. The results show that PBIA fiber has better tensile properties, thermal stability than that of PMIA and PPTA fibers. The onset degradation temperature of PBIA is the highest, namely 421°C in nitrogen. TG-FTIR provides information on the compositions of the pyrolyzates as well as their relationship to the structures of the polyamides. Analysis of the results indicates that a hydrolytic mechanism plays a leading role at lower temperature, and a homolytic mechanism is dominant at higher temperature.
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