Thermochimica Acta最新文献_第10页

A modification to the Friedman and Ortega isoconversional methods for evaluation of the activation energy as a function of conversion and temperature 对弗里德曼和奥尔特加等转换法进行修改，以评估活化能与转换率和温度的关系

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-15 DOI: 10.1016/j.tca.2024.179748

Alireza Aghili , Amir Hossein Shabani

引用次数: 0

Effect of metals and brominated flame retardants on thermal degradation kinetics of waste printed circuit board 金属和溴化阻燃剂对废印刷电路板热降解动力学的影响

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-14 DOI: 10.1016/j.tca.2024.179747

Bibari Boro, Pankaj Tiwari

引用次数: 0

In-situ copper-loaded hollow porous carbon nanospheres derived from phenolic resin for thermal energy storage 用于热能储存的酚醛树脂原位铜负载空心多孔碳纳米球

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-12 DOI: 10.1016/j.tca.2024.179746

Jiahui Wu , Lei Shi , Jie Liu , Yali Luo , Yunfei Liu , Yinong Lyu

{"title":"In-situ copper-loaded hollow porous carbon nanospheres derived from phenolic resin for thermal energy storage","authors":"Jiahui Wu , Lei Shi , Jie Liu , Yali Luo , Yunfei Liu , Yinong Lyu","doi":"10.1016/j.tca.2024.179746","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179746","url":null,"abstract":"<div>Hollow porous carbon nanospheres (HPCS) are ideal scaffolds for phase change materials in thermal energy storage. However, their synthesis traditionally relies on template-based routes, involving tedious procedures and high costs. This study presents a facile method for preparing HPCS through one-step carbonization of phenolic resin using CuCl2 as the activation agent. This mild activation agent not only helps create a rich porous structure, but also maintains the hollow spherical architecture of the polymer precursor. More importantly, copper ions are reduced to copper nanoparticles during the carbonization process and are in-situ loaded into porous carbon, enhancing the thermal conductivity of the scaffold. After incorporating paraffin, the resulting composite exhibits a high phase change enthalpy of 104.4 J g−1, improved thermal conductivity of 0.95 W m−1 K−1, and excellent thermal cycling stability (100.5 J g−1 after 50 heating-cooling cycles), indicating significant potential for thermal energy storage and management.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140552460","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}

引用次数: 0

Modeling of curing and post-curing kinetics for a thermoset adhesive 热固性粘合剂的固化和固化后动力学建模

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-06 DOI: 10.1016/j.tca.2024.179745

Xiumin Zhang , Yuxi Zhao , Huanxiong Xia , Xiaohui Ao , Jianhua Liu , Jiechen Zhou , Yuhe Wang

{"title":"Modeling of curing and post-curing kinetics for a thermoset adhesive","authors":"Xiumin Zhang , Yuxi Zhao , Huanxiong Xia , Xiaohui Ao , Jianhua Liu , Jiechen Zhou , Yuhe Wang","doi":"10.1016/j.tca.2024.179745","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179745","url":null,"abstract":"<div>The properties of adhesives cured at low temperatures are often significantly affected by post-curing effects. This paper introduces a method to model both the curing and post-curing kinetics for thermoset adhesives. The total and residual enthalpies and the glass-transition temperature (Tg) of the adhesive were measured via differential scanning calorimetry. The obtained degree of cure (DOC) and Tg were then fitted to determine their functional relationship. Low-temperature curing experiments were conducted, and an nth-order curing kinetics equation was developed through the fitting of data. Post-curing experiments were performed on samples with varying initial DOCs, and the resulting post-curing data were normalized and fitted using an nth-order model. The relationships between the kinetic parameters and the initial DOC, post-curing temperature and time were analyzed, and a comprehensive kinetics model crossing the curing and post-curing stages was successfully established. Model validation was carried out, and the results demonstrated a good predictive capability.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140539881","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}

引用次数: 0

Polymerization behaviors and properties of benzoxazine resins based-on meta-substituted anilines 基于元取代苯胺的苯并恶嗪树脂的聚合行为和特性

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-06 DOI: 10.1016/j.tca.2024.179743

Shitong Ren , Fangjing Tian , Fengjuan Xiao , Zheng Peng , Yonggang Du

引用次数: 0

Time-temperature-transformation diagrams from isoconversional kinetic analyses applied to the processing and reprocessing of vitrimers 应用于玻璃纤维加工和再加工的等转化动力学分析得出的时间-温度-转化图

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-03 DOI: 10.1016/j.tca.2024.179744

D. Sanchez-Rodriguez , S. Zaidi , L. Carreras , Alaitz Ruiz de Luzuriaga , Alaitz Rekondo , J. Costa , J. Farjas

{"title":"Time-temperature-transformation diagrams from isoconversional kinetic analyses applied to the processing and reprocessing of vitrimers","authors":"D. Sanchez-Rodriguez , S. Zaidi , L. Carreras , Alaitz Ruiz de Luzuriaga , Alaitz Rekondo , J. Costa , J. Farjas","doi":"10.1016/j.tca.2024.179744","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179744","url":null,"abstract":"<div>In this study, we extend the application of Time-Temperature-Transformation (TTT) diagrams, typically employed to describe thermoset processing, to address both the processing and reprocessing of vitrimers. To that end, we have used thermal analysis methods to characterize the reactions governing curing and the thermoforming of a disulfide-containing epoxy vitrimer. The resulting diagrams, which account for adverse processing effects such as degradation and vitrification, exclusively rely on predictions derived from isoconversional methods. Notably, we introduce, for the first time, the application of isoconversional methods to the modeling of stress relaxation kinetics. Using these diagrams, we have identified the conditions for safe curing and thermoforming of the vitrimer. Predictions have been experimentally validated, confirming the robustness and versatility of model-free kinetic analyses.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0040603124000832/pdfft?md5=ff5e8816c568cab4002e3e9743e5f210&pid=1-s2.0-S0040603124000832-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140347578","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}

引用次数: 0

Study of the kinetics of methane-carbon dioxide exchange in gas hydrates below the ice melting point. Experimental data and computational model 冰融点以下气体水合物中甲烷与二氧化碳交换动力学研究。实验数据和计算模型

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-04-02 DOI: 10.1016/j.tca.2024.179737

D.A. Strukov , S.A. Kartopol'cev , A.K. Sagidullin , V.G. Smirnov , A.Y. Manakov , S.S. Skiba

{"title":"Study of the kinetics of methane-carbon dioxide exchange in gas hydrates below the ice melting point. Experimental data and computational model","authors":"D.A. Strukov , S.A. Kartopol'cev , A.K. Sagidullin , V.G. Smirnov , A.Y. Manakov , S.S. Skiba","doi":"10.1016/j.tca.2024.179737","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179737","url":null,"abstract":"<div>Currently, gas hydrates are considered to be a potential resource of natural gas in the future. Vast quantities of gas hydrates deposits are located in the deep sea or in the permafrost zone. Among the other potential methods for extracting natural gas from these deposits is the injection of CO2 into a hydrate-bearing reservoir. This method assumes that carbon dioxide will replace methane molecules in the clathrate framework, so this method may be able to provide long-term burial for greenhouse gas CO2 along with the getting of burning gas. Understanding the kinetics of this process might be crucial for assessing the feasibility of implementation of this technology, but there is currently no clear understanding about the applicability of standard equations for heterogeneous reactions to describe the kinetics of this process. In this paper, we present some recent kinetic data on CH4/CO2 exchange at temperature below the ice melting point, focusing on the composition of hydrates. We also propose theoretical explanations for the obtained data.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140553874","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}

引用次数: 0

Experimental and modeling study of the effect of confinement on the thermal decomposition of organic materials 封闭对有机材料热分解影响的实验和模型研究

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-03-30 DOI: 10.1016/j.tca.2024.179741

Chiara Saggese , Alan Burnham

{"title":"Experimental and modeling study of the effect of confinement on the thermal decomposition of organic materials","authors":"Chiara Saggese , Alan Burnham","doi":"10.1016/j.tca.2024.179741","DOIUrl":"10.1016/j.tca.2024.179741","url":null,"abstract":"<div>Simultaneous Thermal Analysis is widely used to study thermal decomposition of a variety of organic materials, and the choice of experimental conditions is very important to obtain reliable mass loss and heat flow curves. In this work we investigate the effect of confinement on the thermal decomposition of organic materials. As an example, we explore high-density polyethylene (HDPE) and one of its pyrolysis products, namely eicosane (C20H42), through experiments and modeling in open crucibles and crucibles closed with a pierced lid. A new model is developed for evaporation and sublimation from open and pinhole thermal-analysis pans. It considers the kinetic resistance of evaporation at the liquid-vapor interface, inhibition of evaporation by buildup of vapor inside the pan, thermal expansion of vapor inside the pan, and diffusion of vapor from the pan. The model is validated using simultaneous heat-flow and mass-loss measurements of n-eicosane evaporation for various pinhole sizes, down to 50 µm. The importance of product evaporation inhibition for measuring polymer decomposition was demonstrated using HDPE. This study sheds light on the effect of confinement on the mass loss rate of organic materials.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140407121","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}

引用次数: 0

Isoconversional kinetic analysis of thermal decomposition of Bidirectionally stabilized amorphous formulation loading Vitamin D3 (Cholecalciferol) and Calcium Carbonate 负载维生素 D3（胆钙化醇）和碳酸钙的双向稳定无定形制剂热分解的等转化动力学分析

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-03-30 DOI: 10.1016/j.tca.2024.179740

Dijana Jelić , Miho Araki , Kohsaku Kawakami

{"title":"Isoconversional kinetic analysis of thermal decomposition of Bidirectionally stabilized amorphous formulation loading Vitamin D3 (Cholecalciferol) and Calcium Carbonate","authors":"Dijana Jelić , Miho Araki , Kohsaku Kawakami","doi":"10.1016/j.tca.2024.179740","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179740","url":null,"abstract":"<div>Cholecalciferol, generally known as vitamin D3 (VD), and calcium (Ca2+) are very common dietary co-supplements in the pharmaceutical formulations, as they are symbiotically and pharmacologically dependent. Development of the VD/Ca2+ formulation is highly challenging due to stability and solubility issues, mainly for VD instability toward temperature, light, oxygen and pH. In this study, VD was loaded into carrier which consisted of amorphous calcium carbonate (ACC) and hydroxypropyl methylcellulose acetate succinate (HPMCAS), yielding amorphous VD/ACC/HPMCAS formulation with various composition ratios. The structural and thermal stability study of the formulations was conducted to find that VD was a promising molecule for the stabilization of ACC even with the trace amount (0.6 %). On the other hand, ACC stabilized the amorphous state of VD; thus, they had a bidirectional stabilizing effect. The amount of VD played a significant role in thermal stabilization of the VD/ACC/HPMCAS formulations, for which kinetic analysis was performed. Using isoconversional expanded Friedman's model (FRM) activation energies of decomposition of the organic part were determined as 190, 133, and 114 kJ mol−1 for VD/ACC/HPMCAS = 0.6/64.0/35.4, 2.3/56.8/40.9, and 4.9/52.6/42.5 formulations, respectively, revealing that the formulation with the highest amount of VD (4.9 %) was the least stable. The dissolution advantage for VD by amorphization was also demonstrated.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140341388","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}

引用次数: 0

Mathematically correct application of integral isoconversional method 积分等值转换法在数学上的正确应用

IF 3.5 2区化学

Thermochimica Acta Pub Date : 2024-03-30 DOI: 10.1016/j.tca.2024.179739

Tibor Dubaj , Zuzana Cibulková , Peter Šimon

{"title":"Mathematically correct application of integral isoconversional method","authors":"Tibor Dubaj , Zuzana Cibulková , Peter Šimon","doi":"10.1016/j.tca.2024.179739","DOIUrl":"https://doi.org/10.1016/j.tca.2024.179739","url":null,"abstract":"<div>Here we suggest that integral isoconversional method, when applied in a mathematically correct way, can lead to satisfactory results with the least number of adjustable parameters. Differential and incremental methods are used in cases when the apparent activation energy, E, varies with the degree of conversion, α. However, in some cases the observed E(α) dependence can spuriously be induced by small variations in α(T) curves and there is only little to no benefit gained from allowing arbitrary change of E between adjacent conversion levels. As a result, the E(α) dependences are highly “fragile” and subject to minor variations in the experimental data. On the other hand, when the activation energy is optimized globally for all isoconversional levels, a significantly more robust estimate is obtained and the agreement between the experimental and simulated data is still plausible. The approach is demonstrated on two datasets which were evaluated with both variable E(α) dependence and with constant value of E.</div>","PeriodicalId":23058,"journal":{"name":"Thermochimica Acta","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0040603124000789/pdfft?md5=a042590e5011a736cf06d9484117d291&pid=1-s2.0-S0040603124000789-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140344546","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}

引用次数: 0