Haoying Liu , Li Hong , Yanchun Li , Aifeng Jiang , Dongming Song
{"title":"The influence of temperature and humidity on the decomposition of HMX-HTPB polymer-bonded explosives","authors":"Haoying Liu , Li Hong , Yanchun Li , Aifeng Jiang , Dongming Song","doi":"10.1016/j.tca.2025.180003","DOIUrl":"10.1016/j.tca.2025.180003","url":null,"abstract":"<div><div>To investigate the thermal stability of HMX-based polymer-bonded explosives (PBX), this study used thermogravimetric analysis/differential scanning calorimetry (TG/DSC) and accelerated aging tests to examine how temperature and humidity affect the decomposition of HMX-HTPB explosives. Results show that HTPB significantly reduces HMX's thermal stability, leading to a two-stage decomposition process. In the first stage, HTPB cracks and causes minor solid-phase decomposition of HMX, lowering the decomposition temperature from 281.52 °C to 271.20 °C. The second stage involves further decomposition of residual HMX after its melting point at 284.09 °C. After 15 days of aging at 71 °C and 90 % relative humidity, the thermal stability markedly deteriorates, with violent decomposition occurring at 266.51 °C. XRD and FTIR analyses revealed that the distortion of the HMX crystal structure, free radicals from HTPB chain scission, and formation of volatile oligomers are the main factors reducing thermal stability.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"749 ","pages":"Article 180003"},"PeriodicalIF":3.1,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of amorphous structure on the catalytic properties of NiO in the thermal decomposition of typical energy-containing materials","authors":"SiHeng Li, YiFan Jiang, FengQi Zhao, Na Li, Ding Liu, YingNan Dong, WenGang Qu","doi":"10.1016/j.tca.2025.179996","DOIUrl":"10.1016/j.tca.2025.179996","url":null,"abstract":"<div><div>The Nickel oxide (NiO) exhibited good catalytic performance for the thermal decomposition of AP but has limited catalytic activity for RDX and HMX. By adjusting the amorphous state, the number of active sites on the surface of NiO can be increased, thereby enhancing its catalytic activity. In this study, the amorphous NiO (Ra-NiO) with high specific surface area was successfully synthesized and characterized systemically. The Ra-NiO exhibited superior catalytic properties for the thermal decomposition of AP, HMX and RDX. Compared with the commercial γ-NiO, the Ra-NiO decreased the peak decomposition temperature of the HMX by 14.6 °C as well as the activation energy by 213.5 kJ·mol<sup>-1</sup>. Furthermore, the initial decomposition temperature is decreased by 68.8°C and the heat release is increased by 34.5 % (752.4 J·g<sup>-1</sup>). These results underscore the substantial advantages of amorphous modulation in enhancing the catalytic activity of catalysts.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179996"},"PeriodicalIF":3.1,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Umar Abdullahi Isah , Muhammad Imran Rashid , Silas Kiman , Ibrahim Maina Idriss , Habu Mohammed Iyodo
{"title":"Kinetics and heating rates effects on coal devolatilization during pyrolysis","authors":"Umar Abdullahi Isah , Muhammad Imran Rashid , Silas Kiman , Ibrahim Maina Idriss , Habu Mohammed Iyodo","doi":"10.1016/j.tca.2025.179999","DOIUrl":"10.1016/j.tca.2025.179999","url":null,"abstract":"<div><div>Coal type, particle size, and, most importantly, the heating rate under which it occurs influence the degree of swelling and plasticity. The heating method, whether rapid or slow, can significantly impact the pyrolysis characteristics, volatile matter content, softening, devolatilization, and resolidification of coals. As the heating rate increased during pyrolysis, the devolatilization rate shifted to higher temperatures, leading to an increase in both T<sub>max</sub> and R<sub>max</sub>. The activation energy for the primary devolatilization stage increased with increasing heating rates (53.7–59.7 kJ/mol) but decreased for the secondary devolatilization stage (47.6–45.7 kJ/mol), respectively. This trend of results suggests that coal macromolecules decompose more quickly at higher heating rates. However, this study mimicked the coking conditions in the blast furnace by using low heating rates. Future work will consider more coal samples with distinct rheological and petrographic properties.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179999"},"PeriodicalIF":3.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Functionalized phenoxy-imine catalyst for synthesizing highly crystalline nascent UHMWPEs: Isothermal crystallization kinetics of less-entangled systems","authors":"Sheng-Li Wu , Yi Wang","doi":"10.1016/j.tca.2025.180000","DOIUrl":"10.1016/j.tca.2025.180000","url":null,"abstract":"<div><div>This study compares the isothermal crystallization kinetics of nascent less-entangled UHMWPE (<em>PE_30°C_60min</em>, synthesized via 5F-BAOFI/MAO) with conventional highly entangled C-UHMWPE of similar molecular weight. Avrami kinetic and Lauritzen-Hoffman analysis revealed that chain entanglement density critically governs crystallization behavior. The less-entangled <em>PE_30°C_60min</em> demonstrated superior crystallizability, evidenced by more crystalline domains in longer crystallization times compared to C-UHMWPE. Lauritzen-Hoffman calculations quantified interfacial energy differences: <em>PE_30°C_60min</em> exhibited a lower free energy of fold surface (<em>σ</em><sub>e</sub> = 8.16 × 10<sup>-2</sup> J ‧ m<sup>-2</sup>) compared to C-UHMWPE (<em>σ</em><sub>e</sub> = 0.11 J ‧ m<sup>-2</sup>), confirming that reduced chain entanglement enhances crystal growth kinetics. These results establish that tailored synthesis conditions controlling nascent chain entanglement effectively modulate UHMWPE crystallization kinetics and material properties.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"749 ","pages":"Article 180000"},"PeriodicalIF":3.1,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hydrogen-bond density controlled sub-Tg annealing peaks in fast-scanning-chip calorimeter heating scans of non-crystallized aliphatic polyamides","authors":"René Androsch , Christoph Schick","doi":"10.1016/j.tca.2025.179997","DOIUrl":"10.1016/j.tca.2025.179997","url":null,"abstract":"<div><div>A series of aliphatic polyamides (PAs) including PA 6, PA 6.6, PA 6.10, PA 6.12, PA 11, and PA 12 has been subjected to physical aging and analyzed regarding changes of structure during annealing at temperatures around 50 to 100 K below the glass transition temperature (<span><math><msub><mi>T</mi><mi>g</mi></msub></math></span>) for periods up to few hours, employing fast scanning chip calorimetry (FSC). Annealing the amorphous glass of non-crystallized samples at such low temperatures produces endothermic sub-<span><math><msub><mi>T</mi><mi>g</mi></msub></math></span> annealing peaks at slightly higher temperature in subsequently recorded FSC heating scans, scaling in area with the time of annealing for a given annealing temperature. Variation of the annealing temperature furthermore indicates that the underlying process of structure-change slows down with decreasing annealing temperature but not disappears even 100 K below <span><math><mrow><mspace></mspace><msub><mi>T</mi><mi>g</mi></msub></mrow></math></span>. Most important, comparison of the behavior of the various PAs investigated reveals a distinct effect of the chemical structure such that the amount of structure-reorganization (glass relaxation and/or ordering) in a pre-defined period of time reduces with decreasing methylene-group sequence-length between amide groups. It appears that the amide-group concentration in the chains, which determines the density of the hydrogen-bond network to neighbored molecular segments, controls/restricts the re-arrangements of sub-nm sized molecular units.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179997"},"PeriodicalIF":3.1,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiang Gou , Xuan Zhao , Surjit Singh , Mulin Zou , Zhaowei He
{"title":"Synergism study on tri-combustion of cornstalk, polyethylene and anthracite coal","authors":"Xiang Gou , Xuan Zhao , Surjit Singh , Mulin Zou , Zhaowei He","doi":"10.1016/j.tca.2025.179998","DOIUrl":"10.1016/j.tca.2025.179998","url":null,"abstract":"<div><div>The synergistic effects during the tri-combustion of cornstalk, polyethylene, and anthracite coal were investigated using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy. The thermokinetic analysis identifies cornstalk as the most reactive feed material with two reaction stages (38.03 kJ·mol<sup>−1</sup>, 54.63 kJ·mol<sup>−1</sup>) followed by a single reaction stage for both polyethylene (134.60 kJ·mol<sup>−1</sup>) and anthracite coal (118.64 kJ·mol<sup>−1</sup>). Tri-fuel blends exhibit lower activation energies at each combustion stage compared with those of the base components, polyethylene and anthracite coal. Mixed-fuel combustion demonstrates synergistic reaction mechanisms. The proper blending of the feed materials cornstalk, polyethylene and anthracite coal can remarkably improve the characteristic of combustion.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179998"},"PeriodicalIF":3.1,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Weixin Li , Yang Liu , Xuefeng Gui , Ruixiang Zhou , Jiwen Hu , Shudong Lin
{"title":"Thermal decomposition and thermal hazards analysis of typical organic peroxides with impurities","authors":"Weixin Li , Yang Liu , Xuefeng Gui , Ruixiang Zhou , Jiwen Hu , Shudong Lin","doi":"10.1016/j.tca.2025.179992","DOIUrl":"10.1016/j.tca.2025.179992","url":null,"abstract":"<div><div>Organic peroxides in the chemical industry can cause safety risks due to instability, prompting an interest in their thermal stability to avoid dangers. This study investigated the thermal hazards and decomposition mechanisms of cumene hydroperoxide (CHP), dicumyl peroxide (DCP), di-<em>tert</em>-butyl peroxide (DTBP), 1,3-bis(<em>tert</em>-butylperoxyisopropyl)benzene (BIBP), and 2,5-dimethyl-2,5-di-(<em>tert</em>-butylperoxy)hexane (DBPH), and the influence of impurities on these compounds. The thermodynamic properties of these compounds were determined via differential scanning calorimetry (DSC), and their apparent activation energies were calculated by kinetic models. The adiabatic thermal decomposition characteristics were obtained via accelerating rate calorimetry (ARC), and the risk matrix assessment was employed. The decomposition products were characterized via gas chromatography-mass spectrometry (GC–MS), and the corresponding thermal decomposition pathways were proposed. The energy of each step in the proposed pathways was calculated using density functional theory (DFT). The results provide critical guidance for the safe application of these five organic peroxides within the chemical industry.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179992"},"PeriodicalIF":3.1,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yafei Chen , Mengyi Yan , Zhezhi Liu , Daijun Du , Hong Yin , Xiang Zhang , Donglin He , Ping Ouyang , Haifeng Gong , Wanfen Pu
{"title":"Unraveling the influences of isothermal temperature, rock debris and water saturation on tight oil oxidation behavior and kinetics","authors":"Yafei Chen , Mengyi Yan , Zhezhi Liu , Daijun Du , Hong Yin , Xiang Zhang , Donglin He , Ping Ouyang , Haifeng Gong , Wanfen Pu","doi":"10.1016/j.tca.2025.179994","DOIUrl":"10.1016/j.tca.2025.179994","url":null,"abstract":"<div><div>It is critical and fundamental to explore main influence factors on tight oil oxidation behavior and kinetics, which has not been well understood. In this work, thermal analysis and Coats-Redfern method were employed to comprehensively investigate main influence factors. Besides, the most appropriate reaction order (<em>n</em>) was analyzed to obtain kinetic parameters. It suggested three reaction regions with the activation energy variation, and distillation effect was remarkable. Apart from the surface area effect, the addition of rock debris and clay also had the strong catalytic ability to decrease threshold, peak, and ending temperatures. Besides, the <em>n</em> variation implied a more complex, possibly multi-step reaction mechanism. Water existence could strengthen the distillation effect and lower exothermic peaks via suppressing the reaction rate. Moreover, corresponding activation energies indicated the water could promote the oxidation reaction evolution under lower temperatures. From this study, it could provide new insights into the reaction model optimization and numerical simulation for the air injection process.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179994"},"PeriodicalIF":3.1,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Discriminant analysis and neural networks for the identification of phytopathogenic fungi by isothermal microcalorimetry","authors":"Jerusalen Betancourt-Rodríguez , Juan Arturo Ragazzo-Sánchez , Teresa Sandoval-Contreras , Montserrat Calderón-Santoyo","doi":"10.1016/j.tca.2025.179993","DOIUrl":"10.1016/j.tca.2025.179993","url":null,"abstract":"<div><div>This study introduces an innovative method for identifying phytopathogenic fungi through the application of discriminant analysis based on thermokinetic parameters derived from integrated heat flow-time curves obtained via isothermal microcalorimetry. By merging machine learning techniques with multivariate analysis, the research develops a reliable automated tool for fungal identification based on thermogenic analysis. The canonical discriminant analysis effectively distinguishes among the genera <em>Colletotrichum, Penicillium</em>, and <em>Alternaria</em>, providing discriminant canonical variables that served as the foundation for training various machine learning models. Likewise, the neural network model achieved an impressive 95 % fit to the training data, with a low misclassification over around 10 %. The study also discusses the criteria for discrimination and proposes a microcalorimetric database aimed at enhancing future machine learning systems for the identification of phytopathogenic fungi. This methodology represents a pioneering approach that integrates microcalorimetric data analysis with advanced computational techniques, paving the way for more sophisticated and automated diagnostic tools in the field of plant pathology.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179993"},"PeriodicalIF":3.1,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermal decomposition of RDX/NC gun-propellants: A kinetic study","authors":"Samuel Delbarre, Léo Courty","doi":"10.1016/j.tca.2025.179989","DOIUrl":"10.1016/j.tca.2025.179989","url":null,"abstract":"<div><div>Gun propellants are a family of energetic materials designed to produce a high amount of gases during a short period of time. Their accidental ignition can lead to severe accidents that caused many casualties in the past. To overcome this problem, insensitive gun propellants have been developed. However, this loss of sensitivity can lead to ignition issues in operational use. Thermal decomposition of the solid phase is a key step in the ignition process and remains challenging. This paper presents the thermal decomposition of three LOVA gun propellants based on RDX and nitrocellulose. Decomposition is studied by ThermoGravimetric Analysis (TGA) between 30 and 300 °C under nitrogen atmosphere. A kinetic analysis method, previously developed, has been applied to TGA results. Doing so, global kinetic parameters are determined to obtain a solid phase decomposition law. Models using this law provide mass losses in good agreement with TGA results.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"748 ","pages":"Article 179989"},"PeriodicalIF":3.1,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}