Thermochimica Acta最新文献

{"title":"Cure kinetics of aromatic disulfide epoxy vitrimer: influence of epoxy/amine stoichiometry","authors":"F. Spini ,&nbsp;I. Marzorati ,&nbsp;P. Bettini ,&nbsp;A.M. Grande","doi":"10.1016/j.tca.2025.180133","DOIUrl":"10.1016/j.tca.2025.180133","url":null,"abstract":"<div><div>Disposal of End-of-Life (EoL) thermoset composites, difficult to recycle due to polymer crosslinked structure, presents a significant challenge. Development of thermoset polymers with increased recyclability, self-healing, and reprocessability offers a promising solution for managing composite waste and extending component lifetime. Vitrimers, based on covalent adaptable networks (CANs) that rearrange their topology via reversible exchange reactions, are particularly promising.</div><div>Recent research has shown that varying vitrimers stoichiometry can impact properties such as dissolution capability, potentially enhancing recyclability. This study explores the effects of stoichiometry variation on the thermomechanical properties and cure kinetics of epoxy vitrimers incorporating 4-aminophenyl disulfide (4-AFD) as hardener. Knowledge regarding the progression of crosslinking for both stoichiometric and non-stoichiometric mixtures is critical for optimizing processes and predicting behaviour at different curing temperatures.</div><div>Vyazovkin’s approach emerged as the most suitable for analysing cure kinetics among the different methods. It revealed that the non-stoichiometric formulation with hardener excess maintained nearly constant activation energy, suggesting that the cure mechanism is primarily driven by interactions between primary amines and epoxy groups. This reduces the availability of epoxy groups for tertiary amine formation, resulting in a less dense network, lower storage modulus, and decreased T_g, as confirmed by DMA and DSC results.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180133"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004436","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":"Multiscale study of anisotropic thermal expansion in β‑Ga2O3 and modulation of interface heat transfer conductance","authors":"Hui Li,&nbsp;Dongyuan Zhai,&nbsp;Jiwu Lu","doi":"10.1016/j.tca.2025.180130","DOIUrl":"10.1016/j.tca.2025.180130","url":null,"abstract":"<div><div>β-Ga₂O₃, with its ultra-wide bandgap and high breakdown electric field, holds great potential for power switching devices. However, its limited thermal conductivity under high-voltage and high-frequency conditions presents challenges to device performance. This study employs a machine learning-based deep potential (DP) potential to systematically investigate the anisotropic thermal properties of β-Ga₂O₃. By incorporating quantum effects via the quantum thermal bath method, we obtain specific heat values that align better with experimental results. The study further explores the anisotropy of the thermal expansion coefficient and its response to different strain conditions. Additionally, a β-Ga₂O₃(100)/SiC heterostructure is constructed to show that moderate tensile strain optimizes the interface structure and enhances interfacial thermal transport. This work provides a comprehensive theoretical framework for understanding the anisotropic thermodynamic behavior of β-Ga₂O₃ and offers valuable insights for optimizing thermal management in power electronics.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180130"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145045993","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":"Enhanced thermal management and efficiency of porous wavy fin using trihybrid nanofluids: A comparative study with hybrid nanofluids and nanofluids","authors":"P.L. Pavan Kumar ,&nbsp;B.J. Gireesha ,&nbsp;P. Venkatesh","doi":"10.1016/j.tca.2025.180136","DOIUrl":"10.1016/j.tca.2025.180136","url":null,"abstract":"<div><div>The present research introduces the comprehensive thermal evaluation of a fully wet porous wavy fin integrated with trihybrid nanofluid under combined radiative–convective and internal heat generation effects, offering a novel configuration for advanced thermal systems. To advance traditional cooling methods and achieve greater thermal efficiency, the present study investigates the thermal performance of porous wavy fin immersed in trihybrid nanofluid composed of <span><math><mrow><mi>M</mi><mi>W</mi><mi>C</mi><mi>N</mi><mi>T</mi><mo>,</mo><mspace></mspace><mi>A</mi><mi>g</mi><mspace></mspace></mrow></math></span>and<span><math><mrow><mspace></mspace><mi>C</mi><mi>u</mi><mspace></mspace></mrow></math></span>in a base fluid of ethylene glycol and water. Darcy's law is employed to model the interaction between the fluid and the fin porous medium, leading to a second-order nonlinear ordinary differential equation solved using the Runge-Kutta-Fehlberg method and is validated against existing literature. The study graphically examines the effects of key variables including the convective parameter (<span><math><mrow><mi>N</mi><mi>c</mi></mrow></math></span>), radiative parameter (<span><math><mrow><mi>N</mi><mi>r</mi></mrow></math></span>), wave number (<span><math><mi>n</mi></math></span>) and other relevant parameters on the thermal profile and efficiency of porous wavy fin. Further, trihybrid nanofluid outperform hybrid nanofluid and nanofluid due to their superior thermal conductivity. The thermal difference analysis shows that <span><math><mrow><mi>T</mi><mi>H</mi><mi>N</mi><mi>F</mi><mo>−</mo><mi>H</mi><mi>N</mi><mi>F</mi></mrow></math></span> has smaller temperature differences and narrower error bands, while <span><math><mrow><mi>T</mi><mi>H</mi><mi>N</mi><mi>F</mi><mo>−</mo><mi>N</mi><mi>F</mi></mrow></math></span> exhibits larger differences reflecting the lesser efficiency of <span><math><mrow><mi>N</mi><mi>F</mi></mrow></math></span>. The results show that wavy fin in THNF configurations achieve significantly higher temperature distribution and thermal efficiency than both HNF and NF, establishing the THNF–wavy fin combination as an effective solution for next-generation thermal systems. This study provides valuable insights into optimizing porous fin designs and nanofluid applications for thermal management systems.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180136"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145105709","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":"Flame retardancy of phosphorus-containing novolac epoxy-silsesquioxanes","authors":"Mauro Ricardo S. Silveira ,&nbsp;Carlos Arthur Ferreira ,&nbsp;Laurent Ferry ,&nbsp;José-Marie Lopez-Cuesta","doi":"10.1016/j.tca.2025.180139","DOIUrl":"10.1016/j.tca.2025.180139","url":null,"abstract":"<div><div>The phosphorus-containing Novolac Epoxy modified with silsesquioxane (POSS) compounds to enhance flame retardancy and thermal behavior was investigated in this study. Two POSS compounds were used: octaphenyl polyhedral oligomeric silsesquioxane (OctaPOSS), and dodecaphenyl polyhedral oligomeric silsesquioxanes (DodecaPOSS). The results of DMA revealed an increase in the glass transition of the modified samples, with a significant shift in the Tan Delta peak (from 109.0 °C to 127.2 °C), indicating improved thermal stability. Thermogravimetric analysis confirmed enhanced thermal stability and charring effect, with modified samples exhibiting higher residue contents; such as OctaPOSS containing 2 wt% silicon and 1 wt% phosphorus, which produced nearly 6 wt% more residue than neat Novolac Epoxy. Flame-retardant tests, including vertical burning test and limiting oxygen index (LOI), demonstrated the effectiveness of the modified systems. OctaPOSS and DodecaPOSS containing 2 wt% silicon and 2 wt% phosphorus achieved a V0 rating and an LOI of 29.5 %, confirming self-extinguishing performance. Improved flame retardancy and reduced heat release were evidenced by cone calorimetry and microscale combustion calorimetry (MCC). OctaPOSS (2 wt% silicon and 2 wt% phosphorus) showed a 6 2% reduction in peak release rate (pHRR) from 1188 kW/m² for the neat Novolac Epoxy to 455 kW/m², and a heat release capacity (HRC) of 107 J/(g K), approximately 70 % lower than the neat sample. In addition, the fire growth rate reduction of 4.6 kW/(m² s), indicating improved flame retardancy. The combination of POSS and organophosphorus flame retardant also enhanced the charring effect, promoting a more cohesive layer and improving fire safety.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180139"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145158140","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":"Advancements in paraffin wax phase change materials: A comprehensive review of enhancement techniques and thermal storage applications","authors":"Bharathiraja R ,&nbsp;Ramkumar T ,&nbsp;Selvakumar M ,&nbsp;Radhika N ,&nbsp;Praveenkumar N ,&nbsp;Mohanraj M ,&nbsp;Mohamed Iqbal Shajahan","doi":"10.1016/j.tca.2025.180129","DOIUrl":"10.1016/j.tca.2025.180129","url":null,"abstract":"<div><div>Rising energy consumption in recent years has put pressure on electrical infrastructure and sustainability concerns. Efficient energy storage offers a solution to support renewable resources and meet increasing energy needs. Phase change materials (PCMs), particularly paraffin wax, have attracted research interest for their thermal storage potential, but their low thermal conductivity limits practical use. This review article begins with a comprehensive examination on the effect of thermophysical properties of paraffin wax PCMs and also explores their characteristics using different morphological techniques. It further evaluates the impact of various thermal conductivity enhancement techniques on Paraffin wax PCM which could significantly enhance heat transfer rate and system efficiency. Additionally, review article also discusses the preparation methods and applications of nano-enhanced PCM (NPCM). By offering unique insights into the fundamentals and applications of NPCM, this review highlights the current research developments and emerging future trends in this field.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180129"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145026274","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":"Sewage sludge separate pyrolysis and co-pyrolysis with low rank coal: Characteristics, kinetics, and mechanism","authors":"Yao Zhang ,&nbsp;Congcong Shi ,&nbsp;Yugao Wang ,&nbsp;Gang Liu ,&nbsp;Jun Shen ,&nbsp;Yongzhen Yang","doi":"10.1016/j.tca.2025.180110","DOIUrl":"10.1016/j.tca.2025.180110","url":null,"abstract":"<div><div>Co-pyrolysis of sewage sludge (SS) and low rank coal (DC) is a promising approach for achieving efficient resource utilization. In this study, the pyrolysis characteristics of SS, co-pyrolysis of SS and DC, and their interactions were explored by thermogravimetric analysis (TGA). The effects of pyrolysis temperature, heating rate, and mixing ratio on weight loss, energy changes, and kinetics were investigated. The results indicated the main reaction stage of SS occurred at 180–580 °C, giving an activation energy of 265.91 kJ mol⁻¹ calculated by model-free methods. The co-pyrolysis kinetics using model-fitting method revealed that co-pyrolysis of SS and DC is easier to occur than the case without DC. The synergistic effect between SS and DC is proved. The reaction order decreased, and surface reaction and three-dimensional diffusion reaction existed. 2S2D exhibited the lowest activation energy and reaction order. The paper can provide fundamental data and theoretical guidance for sludge-coal co-pyrolysis.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180110"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895041","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":"Research on thermal decomposition and combustion characteristics of ionic liquids","authors":"Lanyun Wang ,&nbsp;Jiahong Yuan ,&nbsp;Yongliang Xu ,&nbsp;Yao Li ,&nbsp;Tingxiang Chu ,&nbsp;Hao Shao ,&nbsp;Xiaodong Feng ,&nbsp;Kun Zhang","doi":"10.1016/j.tca.2025.180125","DOIUrl":"10.1016/j.tca.2025.180125","url":null,"abstract":"<div><div>Ionic liquids have been widely applied in gas separation, high-temperature lubricants, and rocket propellants, so their thermal stability and combustion characteristics have drawn much attention. The study studied 16 kinds of functionalized imidazolium, quaternary ammonium, and quaternary phosphonium ionic liquids. The thermal decomposition and combustion characteristics were studied systematically by a synchronous thermal analyzer and a conical calorimeter. The results indicate that the thermal stability of ionic liquids is greatly affected by the chemical structures. Larger anions can improve the thermal stability, while bromide ions (Br⁻) may weaken it. Moreover, oxidizing gas environment weakens the thermal stability, resulting in two-stage decomposition. In terms of combustion characteristics, higher hydrocarbon content of ionic liquids leads to more total heat release. Long-chain cations and single-atom anions may promote heat generation during combustion. These research results provide essential theoretical support for predicting the risks of ionic liquids in industrial applications and are crucial for enhancing their intrinsic safety.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180125"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917850","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":"New method for quantitative thermal gravimetric analysis per compound - method validation and application to adsorption","authors":"Yves ZEREGA ,&nbsp;Laurence TORTET ,&nbsp;Angélique SIMON-MASSERON ,&nbsp;Sunday Bature GAMBO ,&nbsp;Véronique WERNERT","doi":"10.1016/j.tca.2025.180142","DOIUrl":"10.1016/j.tca.2025.180142","url":null,"abstract":"<div><div>We summarise the numerical method used to process data from conventional thermogravimetric analyser/mass spectrometer coupling, giving the quantified desorption temperature distributions for each compound without requiring evolved gas calibration. The method was validated through experiments involving two compounds adsorbed onto hydrophilic zeolite preloaded with water, either from toluene solutions at varying initial concentrations in isooctane, or under dynamic gas-phase adsorption using 1,2-dichlorobenzene evaporated in a nitrogen flow. These experiments generated overlapping desorption peaks with distinct positions and shapes, representing challenging test conditions. Computed desorbed quantities were compared with adsorbed quantities from the depletion method for toluene at low and high initial concentrations. The sum of the negative-derivative thermogravimetric curves computed per compound closely matched the experimental thermogravimetry curve, confirming amplitude linearity for both thermogravimetry and mass spectrometry responses, and the independent gas mixture transfer. This validates the application of the superposition principle in the model. The close agreement between the adsorbed and computed desorbed quantities for toluene, in the presence of water and isooctane, confirmed the reliability of the numerical approach. Desorbed quantities as low as 2.2 % of the total were accurately resolved. Particular attention was given to sample preparation, especially in relation to hydrophilic materials, leading to the validation of a robust drying protocol. Finally, for the study of competitive adsorption of water and 1,2-dichlorobenzene onto FAU-Nd-Na zeolite, the method showed that 1,2-dichlorobenzene inhibits water adsorption on SIII sites and that increasing neodymium exchange shifts the water desorption temperature distribution towards lower temperatures.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180142"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145227043","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":"Enhanced heat and mass transfer in a high-temperature heat pipe-based thermochemical reactor for hydrogen production","authors":"Zheng Chang ,&nbsp;Jinshu Lu ,&nbsp;Jianwei Zhang ,&nbsp;Zijun Li ,&nbsp;Bo Jiang ,&nbsp;Dawei Tang ,&nbsp;Jing Ma","doi":"10.1016/j.tca.2025.180107","DOIUrl":"10.1016/j.tca.2025.180107","url":null,"abstract":"<div><div>High-temperature thermochemical hydrogen production reactors possess high thermal conductivity and temperature uniformity. However, approximately four orders of magnitude-often exists between the thermal conductivity of the catalyst material and that of the reactor structure. This discrepancy produced a mismatch between the chemical reaction rates and heat transport within the reactor. Our study introduces the metal foam within the catalytic bed to balance the uniformity in heat and mass transfer. The results showed that the metal foam demonstrably improved intra-bed heat transfer, reducing the maximum temperature differential within the catalytic bed by 20 K. Involving a tenfold radial and axial enlargement of the reactor, the overall temperature gradient across the catalytic bed reduced approximately 150 K. Moreover, the reactant space velocity was 2.4 × 10⁴ h⁻¹, the methane conversion increased 11 %. This study underscores that metal foam amplifies heat and mass transfer, optimizing reactant-catalyst synergy to elevate methane conversion efficiency.</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180107"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913785","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":"Investigation of the oxidation and pyrolysis behavior and kinetic mechanism of coal-oil symbiosis under oxygen-deficient conditions","authors":"Lintao Hu ,&nbsp;Hongqing Zhu ,&nbsp;Linhao Xie ,&nbsp;Lei Zhang ,&nbsp;Jiashuo Wang ,&nbsp;Ruoyi Tao ,&nbsp;Baolin Qu","doi":"10.1016/j.tca.2025.180137","DOIUrl":"10.1016/j.tca.2025.180137","url":null,"abstract":"<div><div>Coexistence of coal and oil considerably enhances the complexity and uncertainty of the spontaneous combustion process. This study explores the thermodynamic behavior and kinetic characteristics of coal-oil symbiosis (COS) during oxidation heating at varying oxygen concentrations. The results indicate that oxygen-deficient conditions cause a delay in COS oxidation process, altering its thermodynamic properties. As oxygen concentration decreases, the combustion characteristic index, flammability index ignition characteristic index and ignition stability index under pure nitrogen conditions are reduced by 90.15 %, 83.43 %, 83 % and 18.06 % on average, respectively, compared with those under 20 % oxygen conditions. The analysis of the apparent activation energy (<em>Ea</em>) indicates that lower oxygen concentration leads to a reduction in <em>Ea</em> during the pyrolysis and combustion weight loss stages. Lower oxygen levels also lead to a transition from gas-phase to solid-phase combustion, reducing molecular collision frequency and thus significantly decreasing pre-exponential factor (<em>A</em>).</div></div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":"753 ","pages":"Article 180137"},"PeriodicalIF":3.5,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145045995","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}