Mechanism Of Thermal Decomposition Research Articles

Impact of regioisomerism on unimolecular decomposition reactions of energetic materials: Quantum chemistry modeling of ICM-103 and NAPTO

Energetic regioisomers usually behave different physicochemical properties, and the thermal decomposition mechanism might also be different. In this work, the unimolecular decomposition reactions of two novel energetic isomers, ICM-103 and NAPTO, were investigated through quantum chemistry calculations to reveal the decay mechanism of energetic regioisomers. The molecular properties were first explored to reveal their differences in the molecular properties of ICM-103 and NAPTO. Then, six initial decomposition channels were obtained, including N2 release of azide group, H transfer, O transfer, nitro dissociation, nitro-nitrite isomerization, and ring-opening reaction. Thermochemistry results show that the most possible decay reaction is the cleavage of NN bonds of azide group to generate N2, and the energy barrier of ICM-103 is lower than that of NAPTO, which is consistent with the conclusion that NAPTO is more stable form the experiment. Specially, two molecules react differently, and a sequential N2 loss is expected in one, and N2O loss in the other is almost lost in the clutter. Besides, the nitro dissociation, nitro-nitrite isomerization, and ring-opening reaction energy of ICM-103 are also lower than that of NAPTO. However, for the other same reaction, the energy barrier of ICM-103 is higher than that of NAPTO. These findings in the initial decomposition pathways of ICM-103 and NAPTO could gain more understanding of the effect of regiochemical control on the thermal stability of energetic materials.

Pyrolysis and kinetic modeling study of tetramethylethylenediamine: A potential green propellant

Tetramethylethylenediamine (TMEDA) is a promising green propellant that has been studied as a substitute for hydrazine. An in-depth study of the TMEDA thermal decomposition mechanism is important for future applications in engines. In this work, pyrolysis experiments of TMEDA were carried out in an atmospheric jet-stirred reactor (JSR) from 610 to 1000 K. Abundant intermediate species were analyzed and quantified by synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) and gas chromatography (GC). The results show that the pyrolysis of TMEDA mainly produces hydrocarbons, amines, imines, and nitriles, among which HCN and C2H5N are the main nitrogen-containing intermediates. Based on the experimental results, a detailed chemical kinetic model for describing the thermal decomposition of TMEDA was updated to improve predictions. The updated model can satisfactorily predict the consumption of TMEDA and the generation of most intermediates. Furthermore, detailed experimental measurements combined with kinetic analysis are used to clarify the decomposition reaction pathways of TMEDA. The rate of production (ROP) analysis indicates that unimolecular C-C bond dissociation is one of the leading consumption pathways of TMEDA, forming the (CH3)2NCH2 radical. In addition, the H-atom abstraction reactions involving CH3 radicals formed by the C-N bond dissociation of (CH3)2NCH2 radicals further promote the consumption of TMEDA. Sensitivity analysis highlights that the unimolecular C-C bond dissociation reaction of TMEDA and the reactions involving CH3 radicals mainly control the pyrolysis behavior of TMEDA. The detailed experimental results and kinetic analysis in this work are expected to contribute valuable references to further research on the combustion mechanism of TMEDA.

Thermal stability and pyrolysis mechanism of decamethyltetrasiloxane (MD2M) as a working fluid for organic Rankine cycle

The thermal stability of working fluids is a crucial property studied in the selection of organic Rankine cycle fluids, as they may undergo decomposition at elevated temperatures. In previous studies, siloxanes have been identified as promising choices for ORCs. However, research on the thermal stability of siloxanes in ORCs has been relatively limited. This study investigates the thermal stability and pyrolysis mechanism of MD2M through a combination of experiment, DFT simulation, and ReaxFF-MD calculation. The experiment revealed that MD2M exhibits poor thermal stability, with a decomposition rate of approximately 1.820% at 200°C in 72h. Consequently, it is unsuitable for operating in ORCs at temperatures of 200°C and above. The primary gas products in the pyrolysis of MD2M include CH4, C2H6, C2H4, CO, and CO2, among others. ReaxFF-MD and DFT elucidated the thermal decomposition mechanism of MD2M. The Gibbs free energy barriers for Si-C bond cleavage reactions are relatively lowest, measured at 352.98 and 341.33 kJ∙mol-1, respectively. Simultaneously, methylation of the terminal Si atom is likely to represent the primary reaction pathway for the initial decomposition.

Thermal decomposition and shock response mechanism of crystalline and amorphous 2,4-dinitroanisole (DNAN) by ReaxFF/lg reactive molecular dynamics simulations

DNAN (2,4-dinitroanisole) is a popular melt-cast carrier explosive in the field of insensitive ammunition. The decomposition mechanisms of crystalline and amorphous DNAN were explored in this work through ReaxFF-lg molecular dynamic simulations under constant temperature (2000 K, 2500 K and 3000 K), programmed heating (10 K/ps) and the multiscale shock technique (MSST) (8 km/s, 9 km/s and 10 km/s). The evolution of initial decay reactions, number of products and clusters were performed to reveal the differences in the decomposition mechanisms between crystalline and amorphous of DNAN. Initial molecules of crystals were consumed faster in constant temperature simulations, while initial molecules of amorphous were consumed faster at MSST simulations. The O-C bond breakage was the most important thermolysis reaction and dimerization reaction was the most important shock reaction. Dimerization, intermolecular hydrogen transfer, and intermolecular oxygen transfer occur only at constant temperature and MSST simulations, and direct dissociation reactions of OH groups occur only in the amorphous case. Products analysis showed that CH3O was very important product in all simulations. Clusters analysis showed that the number of clusters in the crystals was greater than in the amorphous case for all shock velocities at MSST simulations. The fitted activation energies showed that the crystalline case was more susceptible to thermal decomposition reactions, and the fitted the initiation pressures for crystalline DNAN was 13.58 GPa, which was higher than the experimental value. There was no doubt that the molecular packing style would affect their decomposition behaviors. These results could help to increase the understanding for decomposition mechanisms of crystalline and amorphous energetic materials.

Effect of Cubic Crystal Morphology on Thermal Characteristics and Mechanical Sensitivity of PYX

To investigate the influence of the cubic crystal morphology on the thermal properties and sensitivity of 2,6-bis(picrylamino)-3,5-dinitropyridine (PYX), cubic PYX (CPYX) crystals were prepared using the antisolvent method. Scanning electron microscopy (SEM), laser particle size analysis, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the morphology, particle size and structure of the prepared products. The thermal behavior, thermal decomposition kinetics, thermal safety parameters and thermal decomposition mechanism of CPYX were investigated by differential scanning calorimetry–thermogravimetry–mass spectrometry–Fourier transform infrared spectrometry (DSC-TG-MS-FT-IR) and in situ FT-IR experiments. Meanwhile, the mechanical sensitivity of CPYX was determined by means of the explosion probability method. The results showed that the product had a smooth cubic morphology and small crystal aspect ratio with an average particle size (d50) of 10.65 μm, but it had no distinct differences from the crystal structure of raw PYX (RPYX). The thermal decomposition peak temperature, the self-accelerating decomposition temperature and the critical temperature of the thermal explosion of CPYX increased by 7.2 °C, 6.1 °C and 10.4 °C, respectively, compared to RPYX. Similarly, the apparent activation energy increased by 15%. Besides these, the impact sensitivity and friction sensitivity of CPYX decreased by 36% and 20%, respectively, compared to RPYX. The decomposition process of CPYX contains two stages. The first stage involves the breakage of N-H bonds and -NO2 groups with the release of CO2, N2O, NO, HCN and H2O, followed by the thermal decomposition of the resulting intermediate and the release of CO2, N2O and HCN in the second stage.

Thermal Decomposition Mechanism of P(DAC-AM) with Serial Cationicity and Intrinsic Viscosity.

The thermal decomposition of the thermodynamic, kinetic and mechanisms of copolymer P(DAC-AM) samples with serial cationicity and intrinsic viscosity ([η]), and the control samples of homopolymer PAM and PDAC, were studied and analyzed using TG, DSC, FTIR. The results of the thermal decomposition thermodynamics confirmed that the thermal decomposition processes of the serial P(DAC-AM) samples and the two control samples could be divided into two stages. It was found that the processes of the copolymer P(DAC-AM) samples were not a simple superposition of those of homopolymers, whose monomers had composed the unit structures of the copolymer, but there were interactions between the two suspension groups. The results of thermal decomposition kinetics showed that the apparent activation energy (E) of the thermal decomposition process of all polymer samples had different varying trends in the terms of weight-loss rate (α). The reaction order (n) of the thermal decomposition of P(DAC-AM) in Stage I and II was close to 1, but in the former and the latter it tended to be 2 and 0.5, respectively. Finally, the thermal decomposition mechanism of copolymer P(DAC-AM) samples was discussed. The above research could not only fill in the knowledge vacancy of the thermal decomposition of the thermodynamic, kinetic and mechanisms of P(DAC-AM), but could also lay a foundation for the study of thermal decomposition mechanisms of the other types of polymers, including cationic polymers.

Thermal decomposition mechanism of lithium methyl carbonate in solid electrolyte interphase layer of lithium-ion battery

To predict the early stages of thermal runaway and improve the safety of lithium-ion batteries, it is necessary to examine the elementary reaction steps for the thermal decomposition of individual solid electrolyte interphase (SEI) components. This study elucidates a detailed decomposition mechanism of lithium methyl carbonate (LMC) which is one of SEI components and accounts for the majority of SEI components formed in commercial electrolytes. The detailed reaction mechanism for the thermal decomposition of LMC is proposed based on the in-situ/ex-situ experiments and density functional theory calculations. LMC underwent six reactions before finally converting to Li2CO3 at 300 °C. To supplement the reliability of the proposed reaction mechanism, the actual gas composition measured using mass spectrometry (MS) are compared with the chain reactions of radicals generated through the thermal decomposition reactions, which is calculated using GRI-MECH 3.0, a gas-phase reaction mechanism. The methodology proposed in this study can be used both for analyzing the reaction mechanisms of different SEI components and their coupling effects with the electrolyte in the future. Understanding these reaction mechanism sets will help us to understand the degradation reactions of real complex SEI and the initial self-heating stage during thermal runaway.

Toward better halon substitutes: Effects of carbon chain length on pyrolytic and fire-suppressing mechanisms of perfluoroalkanes

The use of halon fire extinguishants has led to the depletion of the ozone layer, prompting numerous international organizations to invest significant efforts in finding suitable halon alternatives. Among the counterparts, perfluorinated compounds stand out due to their environmental friendliness, specifically, CF3CF3, CF3CF2CF3 and CF3CF2CF2CF3 have been identified by NASA as the most promising candidates within this chemical family. This study digs into the impact of carbon chain length on thermal decomposition and fire suppression mechanisms of perfluoroalkanes with the three agents as model substances, employing experimental and theoretical analyses. Thermal decomposition products within the temperature range of 600 °C - 900 °C and fire suppression performances, including fire-extinguishing concentrations (9.38 vol.%, 7.81 vol.%, and 6.87 vol.%, respectively), variation of the flame morphology and temperature, are intensively analyzed and compared for the three perfluoroalkanes. Theoretical calculations indicate a decrease in carbon chain stability with the increasing chain length, and CF3CF2CF2CF3 manifests the most diversified self-decomposition paths at low energy barriers. Moreover, a wider spectrum of free radicals can be generated from the longer carbon chain via the CC cleavage, which can efficiently react with and continuously consume flame radicals (H• and OH•) to interrupt the combustion chain reaction. These findings enrich the structure-performance relationship of perfluoroalkanes, highlight the potential of specific perfluorinated compounds as viable halon alternatives and offer theoretical guidance for the selection and design of environmentally benign and efficient halon substitutes.

Unraveling the characteristics and pyrolysis mechanism of diethylene glycol dinitrate plasticized nitrocellulose supplemented with organic stabilizers

The current work examined the properties and thermal decomposition mechanism of a double-base propellant comprising nitrocellulose (NC), diethylene glycol dinitrate (DEGDN), and organic stabilizers. To achieve this objective, a comprehensive analysis was conducted on the influence of stabilizers, namely 2-nitrodiphenylamine (2-NDPA), 1,3-dimethyl-1,3-diphenylurea (MC), and kraft lignin, on the characteristics and pyrolysis gases of NC/DEGDN. Experimental findings demonstrated that kraft lignin has a good stabilizing efficiency, similar to that of 2-NDPA and MC stabilizers. Moreover, differential scanning calorimetry (DSC) experiments revealed that the incorporation of MC, 2-NDPA, and Kraft lignin has increased the maximum peak temperature of the main thermolysis process from Tpeak = 192.1 °C for NC/DEGDN baseline to Tpeak = 194.5 °C for NC/DEGDN/MC, Tpeak = 193.3 °C for NC/DEGDN/2-NDPA, and Tpeak = 194.3 °C for NC/DEGDN/Kraft lignin. In addition, differences in the stabilization mechanism for each stabilizer were examined using thermogravimetry connected to an infrared spectroscopy (TGA-FTIR). The obtained findings highlighted the discernible influence of stabilizer types on the gaseous products of NC/DEGDN propellant, particularly elucidating their effects on the intensity and type of nitrogen oxides generated throughout the pyrolysis process.

Effect of traditional solvent on thermal decomposition mechanism of lignin: A density functional theory study

In order to understand the effect of traditional solvents on lignin pyrolysis, the decarbonylation and decarboxylation reactions of various phenylic lignin model compounds were theoretically investigated using DFT methods at M06-2×/6–31++G(d,p) level. The calculation results show that activation energy of the decarbonylation and decarboxylation reactions of lignin model compounds can be reduced when H2O/CH3OH existed. There are two types of reaction for the H2O/CH3OH during the pyrolysis. For first type, the synergistic reaction of lignin with H2O/CH3OH as hydrogen transfer carrier. The energy barriers of the main elemental reaction steps during this type of pyrolysis are about 285.0–300.0 kJ/mol (H2O) and 275.0–290.0 kJ/mol (CH3OH) (decarbonylation), 170.0–210.0 kJ/mol and 155.0–200.0 kJ/mol (decarboxylation). For another type, the synergistic reaction of lignin with H2O/CH3OH as hydrogen source. The energy barriers of the main elemental reaction steps during this type of pyrolysis are about 260.0–278.0 kJ/mol and 240.0–260.0 kJ/mol, 303.0–312.0 kJ/mol and 291.0–297.0 kJ/mol. Furthermore, the reaction temperature has the most significant impact on decomposition reaction of lignin in a methanol medium, suggesting that the reaction in the methanol medium is better than that in the water environment.

Optimising Low Temperature Pyrolysis of Mesoporous Alginate-Derived Starbon® for Selective Heavy Metal Adsorption.

In response to the ever increasing need to develop more efficient and sustainable methods for removing heavy metal contaminants from aqueous systems, the following article reports on the design of highly mesoporous alginate-derived materials (Starbon®) and their application to the adsorption of heavy metals. Using the Starbon® process to expand, dry and pyrolyse an inherently porous polysaccharide precursor, it was possible to produce mesoporous materials (BJH mesopore volumes 0.81-0.94 cm3 g-1) with large surface areas (157-297 m2 g-1) across a range of low pyrolysis temperatures (200-300 °C). The mechanisms of thermal decomposition were explored in terms of chemical and structural changes using N2-sorption porosimetry, thermogravimetric analysis, titration, FT-IR spectroscopy and 13C NMR spectroscopy. It was found that, as a result of intermolecular dehydration and crosslinking, sufficient chemical stability is obtained by the intermediate temperature of 250 °C, with limited improvement seen at higher temperatures. In addition, the materials retained large metal adsorption capacities (0.70-1.72 mmol g-1) as well as strong selectivity for Cu2+ ions (over Co2+ and Ni2+), as compared to commercial petrochemical-derived cation exchange resin Amberlite™ Mac 3H. Thus, highlighting the potential of Starbon® materials as a sustainable answer to the widespread problem of heavy metal-contaminated wastewaters.

Study of thermal decomposition mechanism of methylene diphenyl diisocyanate (MDI) through accelerating rate calorimeter and theoretical approach

Study of thermal decomposition mechanism of methylene diphenyl diisocyanate (MDI) through accelerating rate calorimeter and theoretical approach

Thermodynamics and energy properties of the lowest eutectic mixture of TNBA/MTNP

In light of the challenges posed by the low density, diminished energy levels, and shrinkage holes in the loading arise of the current cast-cured explosive liquid vehicle, TNT, the investigation of low-melting eutectic materials as potential substitutes for TNT has emerged as a focal point of research. By employing the solvent-nonsolvent method, the lowest eutectic mixture of TNBA(2,4,6-trinitro-3-bromoanisole)/MTNP(1-methyl-3,4,5-trinitropyrazole) was synthesized, distinguished by a moderate melting point and markedly elevated energy levels as compared to TNT. Comprehensive SEM, EDS, IR, XRD, and XPS analyses were conducted on the lowest eutectic mixture, substantiating the absence of any chemical interaction between TNBA and MTNP and affirming their exceptional compatibility. Moreover, an exploration into the thermal decomposition behavior and mechanism of the lowest eutectic mixture was undertaken, its mechanical sensitivity was tested, and its detonation performance was evaluated by EXPLO-5 software. The thermal decomposition parameters of the lowest eutectic mixture closely paralleled those of the precursor materials, with the thermal decomposition kinetics model function being identified as the Jander function. The impact sensitivity of the lowest eutectic was 48.1 cm and the friction sensitivity was 12%. Furthermore, the density of the lowest eutectic mixture surpassed 1.8 g/cm3, and its detonation velocity approached 8000 m/s, markedly surpassing the explosive performance of TNT.

Synthesis, characterization, and thermal pyrolysis mechanism of high temperature resistant phenolphthalein-based poly (arylene ether nitrile)

Phenolphthalein (PP) is usually used as a functional monomer to design novel high performance polymers with adjustable thermal, mechanical, and fluorescent properties. In this study, a soluble, amorphous, high temperature resistant PP-based poly (arylene ether nitrile) (PAEN) was synthesized and its corresponding thermal decomposition mechanism was reported via TGA/DTG, TGA/FTIR and TGA/MS analysis. PP-based PAEN showed a Tg of 250 °C a Tdmax of 503 °C and a char residue of 59.2 % at 800 °C, respectively. According to Kissinger and Flynn–Wall–Ozawa model, the activation energy of thermal pyrolysis was calculated as 225 ± 4 and 284 ± 17 kJ/mol respectively, higher than those of other poly arylene ethers. PP-based PAEN showed a three-stage thermal pyrolysis mechanism. Its initial degradation happened before 400 °C and liberated the inherent moisture. The latter backbone decomposition between 400 and 600 °C involved multiple routes mainly from the CO and CC cleavages of lactone ring, resulting in a Ph2CHPhOPh intermediate by releasing HCHO, HCOOH, CO2, H2O, CH4, C6H6, and C6H5OH. The third carbonization stage over 600 °C included the transformation from biphenyl linkages to aromatic graphite by dehydrogenation. This study not only gives a comprehensive understanding of the thermal pyrolysis behavior of PP-based PAEN, but also provides valuable references for the thermal behaviors of other PP-containing polymers.

Thermal behaviors and Decomposition Mechanism of PNIMMO with CL-20

To investigate the thermal decomposition mechanism between Poly(3-nitratomethyl-3- methyloxetane) (PNIMMO) and 2, 4, 6, 8, 10, 12-Hexanitrohexaazaisowurtzitane (CL-20), the thermal decomposition of PNIMMO, CL-20 and PNIMMO+CL-20 mixture under different conditions was studied using differential scanning calorimetry (DSC), thermogravimetric-differential scanning calorimetry-mass spectra-fourier transform infrared spectrometer (TG-DSC-MS/FTIR) and in-situ FTIR experiments. As a result, the exothermic peak temperature of the PNIMMO+CL-20 mixture shifts to lower values under both closed and open circumstances compared to CL-20. Different kinetic parameters and models were obtained for the three decomposition steps in the mixture. The first step follows the random chain scission model (L2) at α<0.5, and the phase boundary controlled reaction model (R3) at α>0.5. The second/third step is between the random chain scission model (L2) and the first-order reaction model (F1) at α<0.5, and conforms to the first-order reaction model (F1) at α>0.5. Thus, the decomposition of PNIMMO controls the initial speed, while the removal of the nitro group in CL-20 controls the later step. Combined with the analysis of gas products and condensed phase, PNIMMO speeds up the N—NO2 bond breaking in CL-20 but doesn’t alter its initial breakdown route.

Thermal stability and decomposition mechanism of Mo2AlB2 in argon atmosphere

Mo2AlB2 is a new and metastable phase in the MAB phase family. The lamellar Mo2AlB2 compound is considered to be an optimal candidate for preparing 2D MoB nanosheets. However, studies have less focused on its thermostability as compared with other MAB phases. In this work, the thermal stability of Mo2AlB2 was studied under Ar atmosphere to understand its limited applications. The results showed that Mo2AlB2 slowly decomposed at above 800 °C, but completely decomposed into MoB and Al at 1100 °C for only 0.5 h. Based on the experimental results and density functional theory calculations, the decomposition mechanism of Mo2AlB2 phase was analyzed.

Unveiling the thermal decomposition mechanism of high-nickel cathode with loaded nano-Al2O3 on conductive carbon for safe lithium-ion batteries

High-nickel single-crystal LiNixCoyMnzO2 (NCM) has become the preferred cathode candidate for next-generation lithium-ion batteries because of its high capacity and great structural stability. Its thermal decomposition process and thermal stability enhancement strategies, however, require in-depth research before large-scale implementation. In this work, atomic layer deposition (ALD) technique is used to uniformly load Al2O3 nanoparticles on acetylene black (AB). The modified AB was used as the conductive agent for single crystal LiNi0.87Co0.05Mn0.08O2 composite cathode to fabricate the electrode. It shows that the thermal stability of the delithiated composite cathodes with electrolytes is significantly improved such as the 44 % drop in maximum heat flow from 5.59 mW mg−1 to 3.15 mW mg−1 and the phase transition from spinel to rock salt is delayed with comparable electrochemical performance. Furthermore, the thermal decomposition mechanism of the delithiated composite cathodes with electrolytes was carefully investigated by ex-situ MS, XPS, DRIFT and TG-MS. Our results disclose that the nano-Al2O3 particles could catalyze the dehydrogenation reaction of solvent on the surface of cathode. If the cathode is consumed in such a more moderate way in advance, the heavy heat release due to the oxidation of solvents by active oxygen species will be reduced significantly, thus improving the thermal stability of the cathode and the safety of the battery.

Synthesis, characterization and thermal decomposition mechanism of new 5-amino-3-hydrazinyl-1H-1,2,4-triazole-based energetic materials

The construction and comprehensive characterization of energetic ionic salts 5-amino-3-hydrazinyl-1H-1,2,4-triazolium diperchlorate (2) and 5-amino-3-hydrazinyl-1H-1,2,4-triazolium 3-nitro-1,2,4-triazolate-5-one (3), which are based on 5-amino-3-hydrazinyl-1H-1,2,4-triazole, were conducted. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were employed to explore the thermal and kinetic behaviors of the novel energetic ionic salts. An isoconversional approach and non-linear regression analysis were employed to propose accurate kinetic models for characterizing the decomposition of the energetic ionic salts based on the data from DSC and the most possible mechanism functions governing the decomposition of 2 and 3 was determined. Furthermore, experimental measurements and theoretical calculations were employed to examine diverse physicochemical characteristics, including densities, mechanical sensitivities, heat of formation as well as detonation parameters. The findings suggest that salt 2 exhibits a good detonation pressure of 37.4 GP and a satisfactory detonation velocity of 9031 m/s, exceeding RDX in terms of energy content and suggesting its potential as a viable high-energy explosive substitute for RDX. While salt 2 exhibits a slightly lower level of detonation performance than HMX, it possesses better sensitivity, which mean that salt 2 retains a considerable potential for valuable applications.

Thermal decomposition kinetics and mechanism of poly(ethylene 2,5-furan dicarboxylate) Nanocomposites for food packaging applications

Poly(ethylene 2,5-furan dicarboxylate) (PEF) based nanocomposites containing different nanoparticles like Ag, TiO2, ZnO, ZrO2 Ce-Bioglass, have been synthesized via in-situ polymerization techniques targeting food packaging applications. Zeta potential measurements showed an increase in the negative zeta potential value due to an increase in the surface charge density of the nanocomposites. Thermogravimetric analysis results proved that, except PEF-ZnO nanocomposite, all the other nanocomposites exhibited good resistance to thermal degradation without serious mass loss until 330 °C. Thermal decomposition kinetic analysis and the dependence of activation energy on the degree of conversion (α), indicated that the presence of ZnO nanoparticles influences, the degradation mechanism of PEF. In contrast, the presence of Ce-Bioglass nanoparticles leads to a slower degradation process, contributing to the enhanced resistance to thermal degradation of the PEF-Bioglass nanocomposite. The thermal degradation mechanism of PEF nanocomposites analyzed by pyrolysis‒gas chromatography/mass spectrometry (Py-GC/MS) indicated that the primary thermal degradation mechanism for the studied nanocomposites was β-hydrogen bond scission, while to a lesser extent, α-hydrogen bond scission products were noted in PEF-TiO2 and PEF-ZrO2 nanocomposites.

Thermal behavior and decomposition mechanism of ammonium perchlorate in the presence of C–N conjugated polymers based on diaminomaleonitrile

Thermal behavior and decomposition mechanism of ammonium perchlorate in the presence of C–N conjugated polymers based on diaminomaleonitrile