Katarzyna Gańczyk-Specjalska

Dr. Katarzyna Gańczyk-Specjalska

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Research Focus & Metrics

Academic Career Length

57Years (1970-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 January 2020 in Journal of Thermal Analysis and Calorimetry
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KCKatarzyna Cieslak
Katarzyna Cieslak
KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
KDKatarzyna Drożdżewska-Szymańska
Katarzyna Drożdżewska-Szymańska
MUMichał Uszyński
Michał Uszyński
The granules containing nitrogen of various content (12.2–13.3%) and stabilizers (centralite I, centralite II, akardite II, triphenylamine) were obtained in laboratory scale, and the study of their physicochemical and thermal properties was conducted. It has been observed that the helium density of granules depends on the degree of gelling of nitrocellulose by the stabilizer as well as the lack of effect of the stabilizer type on the heat of combustion value. In turn, the heat of combustion depends on the content of nitrogen in nitrocellulose. Granules of 13.3% N nitrocellulose were characterized by a more rapidly developing thermal decomposition than the granules containing 12.2 and 12.9% N nitrocellulose. The maximum temperature of decomposition shifts toward higher temperatures (from 207.6 to 209.8 °C) with decreasing nitrogen content in nitrocellulose for granules containing triphenylamine as a stabilizer. All values of heat generation rate obtained for granules with triphenylamine were lower than the respective rates for granules with centralite I. Thermal properties and chemical stability of granules containing triphenylamine have better properties, when compared to other examined stabilizers. On the basis of differential scanning calorimetry and thermogravimetry, kinetic parameters were calculated by means of Ozawa–Flynn–Wall analysis. The effect of stabilizers and nitrogen content on kinetic parameters was determined. The kinetic model of thermal decomposition of granules was adjusted—the best fit was nth-order reaction with autocatalysis. The activation energy of thermal decomposition process according to the adopted chemical reaction model increases from 190 to 239 kJ mol−1 with increasing nitrogen content in the granulate.

28 April 2016 in Journal of Thermal Analysis and Calorimetry
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KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
AZAngelika Zygmunt
Angelika Zygmunt
TGTomasz Golofit
Tomasz Golofit
TEX is a thermostable compound and less sensitive to external stimuli. It sublimates and decomposes at high temperature. The influence of DSC and TG measurement conditions and substance mass on the thermal decomposition of TEX was determined. It was observed that substance mass, pan type and fulfillment degree of pan influence the thermal decomposition and kinetic parameters of TEX decomposition. Sublimation of the sample was the main observed process; thermal decomposition was the secondary process during the heating of TEX in open pans. With increasing substance mass, the participation of thermal decomposition of TEX increased. Uncontrolled thermal decomposition was observed for larger mass of a sample. The sublimation and decomposition processes were confirmed by FT-IR method. Thermal decomposition was the main process observed during heating the sample of TEX in hermetic pans. Sublimation of a sample was marginal. The sublimation effect decreased with increasing the degree of fulfillment pan. The kinetic parameters were determined with the Friedman’s isoconversional method. The conversion, mass of sample and the type of pan caused the large changes in the values of kinetic parameters. The apparent activation energy varied from 128 to 355 kJ mol−1 and logA varied from 9.95 to 30.64 in initial step (α = 0.02) for different condition of measurements. The low values of apparent activation energy (about 130 kJ mol−1) were associated with sublimation process and the high values (about 340 kJ mol−1) with the decomposition process.

13 April 2023 in Propellants, Explosives, Pyrotechnics
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KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
KCKatarzyna Cieslak
Katarzyna Cieslak
MJMarcin Jakubczak
Marcin Jakubczak
KDKatarzyna Drożdżewska‐Szymańska
Katarzyna Drożdżewska‐Szymańska
WTWaldemar Tomaszewski
Waldemar Tomaszewski
PPPiotr Prasuła
Piotr Prasuła

1 January 2018 in Polimery
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TGTomasz Golofit
Tomasz Golofit
KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
KJKarolina Jamroga
Karolina Jamroga
LKLukasz Kufel
Lukasz Kufel
Mixtures of hydroxyl-terminated polybutadiene (HTPB) and dioctyladipate (DOA) as a plasticizer, which after crosslinking are applied as binders in heterogeneous propellants, were studied.The influence of mixture composition on rheological and thermal properties, important from technological and utility viewpoint were specified. The temperature dependence of prepared mixtures viscosity were studied. Systems were subjected to crosslinking and values of pot life (tpl) were determined. It was stated that tpl rose with increasing plasticizer content. Differential scanning calorimetry and thermogravimetry techniques were used toanalyze thermal stability of mixtures. It was concluded that applied component scould not decompose in the temperature range of 290–350 K and studied mixtures did not cause the hazard of thermal explosion.

25 November 2020 in Materiały Wysokoenergetyczne / High Energy Materials
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KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
PMPaulina Magnuszewska
Paulina Magnuszewska
The paper presents the thermomechanical properties of solid rocket propellants containing hydroxyl-terminated polybutadiene. Dynamic mechanical analysis (DMA) was used in analysing the mechanical properties of propellant for two different sample geometries (cuboid and cylindrical). Nonisothermal and isothermal analyses were carried out in two holders: dual-cantilever and compression. The glass transition temperature of soft and hard segments in the propellants, the effect of dynamic force on sample strain, the creep-relaxation process (based on which parameters in the Burgers model were calculated) were determined based on the results of the analysis.

12 September 2021 in Journal of Thermal Analysis and Calorimetry
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KCKatarzyna Cieślak
Katarzyna Cieślak
KGKatarzyna Gańczyk-Specjalska
Katarzyna Gańczyk-Specjalska
KDKatarzyna Drożdżewska-Szymańska
Katarzyna Drożdżewska-Szymańska
MKMarta Królikowska
Marta Królikowska
MJMarcin Jakubczak
Marcin Jakubczak
Examinations of two-component mixtures, namely: triphenylamine + centralite I (TPA + CI) and triphenylamine + akardite II (TPA + AkaII) were carried out using differential scanning calorimetry (DSC), which served to determine phase diagrams. Experimental data were described with NRTL model and eutectic points for both systems were determined. For TPA + CI system, they were equal to xEu,TPA = 0.2899, TEu = 62.9 °C, whereas for TPA + AkaII system they amounted to xEu,TPA = 0.7868, TEu = 117.5 °C. Granules contain mixtures of eutectic composition were obtained. The physicochemical and thermal properties of resultant single base granules were studied. The helium density of both granules was approx. 1.47 g cm−3, the average dynamic force amounted to 0.55–0.60 bar−1 s−1, and the calorific value ranged from 3060 to 3095 J g−1. Both granules should be chemically stable for 10 years of storage at 25 °C; they meet the requirements of STANAG 4582 standard. DSC analysis of decomposition processes was used to determine kinetic parameters and to adjust the chemical reaction model of nth order with autocatalysis (CnB). Reaction order ranged from 2.6 to 3.0, while the activation energy was similar (197–198 kJ mol−1). Based on examination of thermal properties, it was observed that both eutectic mixtures of stabilizers prevent the decomposition reaction more efficiently than the use of individual compounds as stabilizers.