Macromolecular Theory and Simulations最新文献_第2页

Theories of the Effects of Copolymer Addition on the Interfacial Tension between Polymer Blend Components: A Review 共聚物加成对聚合物共混组分界面张力影响的理论综述

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-03-03 DOI: 10.1002/mats.202400105

Ivan Fortelný, Josef Jůza

{"title":"Theories of the Effects of Copolymer Addition on the Interfacial Tension between Polymer Blend Components: A Review","authors":"Ivan Fortelný, Josef Jůza","doi":"10.1002/mats.202400105","DOIUrl":"https://doi.org/10.1002/mats.202400105","url":null,"abstract":"This review discusses methods for calculating the equilibrium interfacial tension in strongly immiscible polymer blends compatibilized with copolymers. The discussion is focused on typical polymer blends with fine phase structures; in these polymer blends, the volume of the interfacial layer is generally not negligible with respect to the volume of the bulk phases. The main models and calculation procedures that are predominantly used are compared, and their practicalities are discussed. Neither the expressions derived using the dry brush approximation nor those derived using the wet brush approximation are applicable to blends compatibilized with copolymers that have block lengths comparable to those of the compatibilized homopolymers. The amount of a copolymer in the interfacial layer of a polymer blend is generally not negligible with respect to its amount in the bulk phases. Therefore, approximations that are successfully used for the calculation of the interfacial tension measured by common methods cannot be applied to calculation of the interfacial tension in the polymer blends.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"34 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mats.202400105","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144091276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Entropic Repulsion and Local Order in Doubly Tethered Polymers on a Surface 表面上双系链聚合物的熵排斥和局部序

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-02-20 DOI: 10.1002/mats.202400077

Min Chu, Dieter W. Heermann

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Dynamic Modeling of Vinyl Chloride Suspension Polymerization in a Continuous Oscillatory Baffled Reactor 连续振荡折流板反应器中氯乙烯悬浮聚合动力学建模

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-02-07 DOI: 10.1002/mats.202400089

Jonildo dos Santos Silva, Príamo Albuquerque Melo, Rita Marinho, Normando José Castro de Jesus, Márcio Henrique Santos Andrade, Priscila Martins Beck, José Carlos Pinto

{"title":"Dynamic Modeling of Vinyl Chloride Suspension Polymerization in a Continuous Oscillatory Baffled Reactor","authors":"Jonildo dos Santos Silva, Príamo Albuquerque Melo, Rita Marinho, Normando José Castro de Jesus, Márcio Henrique Santos Andrade, Priscila Martins Beck, José Carlos Pinto","doi":"10.1002/mats.202400089","DOIUrl":"https://doi.org/10.1002/mats.202400089","url":null,"abstract":"In the present work, a phenomenological model built to represent the suspension polymerization of vinyl chloride in a continuous oscillatory baffled reactor is presented for the first time. Following a previous work (Silva et al., Chemical Engineering Science, 288, 119845, 2024), a tanks-in-series model is employed to represent the reactor and a backflow stream is also considered to simulate backmixing. The intrinsic heterogeneous behavior of vinyl chloride polymerization adds model complexity in comparison to vinyl acetate polymerization reported in the literature. Moreover, the stronger gel effect also makes the temperature control difficult since a higher number of cooling jackets is required to keep a uniform temperature profile. The influence of residence time on reactor operation is investigated. Furthermore, the effects of initiator type and injection points on the polymerization rates and polymer properties are evaluated and shown to influence the process operation significantly.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"34 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144091224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Front Cover: Macromol. Theory Simul. 1/2025 封面：Macromol。理论模拟1/2025

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-01-16 DOI: 10.1002/mats.202570001

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Issue Information: Macromol. Theory Simul. 1/2025 发布信息：Macromol。理论模拟1/2025

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-01-16 DOI: 10.1002/mats.202570002

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Investigations of Microstructures and Properties of SPEEK-[BMIm][OTf] Ionic Liquid Composite Membrane for Fuel Cells 燃料电池用SPEEK-[BMIm][OTf]离子液体复合膜的微观结构和性能研究

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2025-01-13 DOI: 10.1002/mats.202400080

Shute Yu, Lanlan Qin, Zhaohong Miao, Jian Zhou

{"title":"Investigations of Microstructures and Properties of SPEEK-[BMIm][OTf] Ionic Liquid Composite Membrane for Fuel Cells","authors":"Shute Yu, Lanlan Qin, Zhaohong Miao, Jian Zhou","doi":"10.1002/mats.202400080","DOIUrl":"https://doi.org/10.1002/mats.202400080","url":null,"abstract":"Utilizing ionic liquids in proton exchange membranes can greatly enhance the performance of fuel cells, enabling their application in high-temperature and dry conditions. Further advancements in this field depend on a fundamental comprehension of their structural characteristics. This study focuses on the sulfonated poly(ether ether ketone) (SPEEK)-1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIm][OTf] composite membrane system. Effects of sulfonation degree, ionic liquid content, and temperature on the structure and conductivity of the composite membrane are investigated by dissipative particle dynamics (DPD) and molecular dynamics (MD) simulations. Results show that [BMIm][OTf] is predominantly distributed around the sulfonic acid groups of SPEEK. At an optimal sulfonation degree and ionic liquid content, interconnected ionic liquid channels can be formed. Nevertheless, an excessively high sulfonation degree may jeopardize the stability of the membrane structure. Moreover, the aggregation of ionic liquid occurs at a high level of ionic liquid content, which hinders the efficient transfer of protons. Generally, increasing the temperature is more conducive to the formation of monodisperse ionic liquid channels within the SPEEK-[BMIm][OTf] composite membrane; however, overhigh temperature may compromise the integrity of the composite membrane structure. The findings of this study offer molecular insights for the development of high-temperature proton exchange membrane fuel cell systems.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"34 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144091229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Experimental Study on Polymer–Polymer Interfacial Thermal Resistance 聚合物-聚合物界面热阻实验研究

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2024-12-23 DOI: 10.1002/mats.202400088

Yinfeng Xia, Takushi Saito, Tatsuya Kawaguchi

{"title":"Experimental Study on Polymer–Polymer Interfacial Thermal Resistance","authors":"Yinfeng Xia, Takushi Saito, Tatsuya Kawaguchi","doi":"10.1002/mats.202400088","DOIUrl":"https://doi.org/10.1002/mats.202400088","url":null,"abstract":"This study presents an experimental measurement of interfacial thermal resistance (ITR) at polymer–polymer interfaces using a multi-layered bulk sample approach. ITR is commonly measured using thin-film techniques, but new advancements enable testing in bulk materials with multilayered structures. However, traditional multilayer fabrication is often resource-intensive and lacks consistency. This study introduces a simple rotational overlapping method for fabricating multi-layered polymer samples for bulk ITR measurement. Combining numerical simulations with experimental validation, researchers optimize layer overlapping conditions using measured viscosity data of high-density polyethylene (HDPE), polypropylene (PP), and polylactic acid (PLA). Samples are fabricated at viscosity-matching temperatures, and shear forces from stirring disks create uniform layer patterns. Computational fluid dynamics (CFD) simulations elucidate the layer formation mechanism, enabling the fabrication of samples with over 112 layers within a 4.6 mm thickness. ITR testing reveals a direct correlation between layer number and thermal resistance. PE-PP samples exhibit an average ITR of 9.58 × 10−6 K m2 W−1, with a 10.32% increase in resistance from 38 to 112 layers. Similarly, PE-PLA samples with an ITR of 1.31 × 10−5 K m2 W−1 show a 2.8% increase from 5 to 23 layers. Overall, The experimental procedure provides valuable data to advance the understanding of ITR in polymer–polymer interfaces.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"34 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mats.202400088","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143639195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Comment on Copolymer Randomization by End-Group Interchain Exchange Reactions 端基链间交换反应对共聚物随机化的影响

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2024-12-20 DOI: 10.1002/mats.202400099

Ryszard Szymanski, Yaroslav V. Kudryavtsev

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Z-Average of Cross-Linked Copolymers and Branched Polycondensates 交联共聚物和支化缩聚物的z -平均值

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2024-12-20 DOI: 10.1002/mats.202400073

Rolf Bachmann, John T. Bendler

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The Influence of Length-Diameter Ratio of Cellulose on Friction Characteristics of Screw Surface Investigated by EDEM Simulation 通过 EDEM 仿真研究纤维素长径比对螺杆表面摩擦特性的影响

IF 1.8 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2024-12-13 DOI: 10.1002/mats.202400083

Xuan Yin, Dingyao Zhang, Liqi Li, Bing Zhang

{"title":"The Influence of Length-Diameter Ratio of Cellulose on Friction Characteristics of Screw Surface Investigated by EDEM Simulation","authors":"Xuan Yin, Dingyao Zhang, Liqi Li, Bing Zhang","doi":"10.1002/mats.202400083","DOIUrl":"https://doi.org/10.1002/mats.202400083","url":null,"abstract":"This study integrates numerical simulations and tribological experiments using a plate-on-disc tribometer to examine the tribological behavior and wear mechanisms of cellulose materials in the solid transport screw of a parallel co-rotating twin-screw extruder. EDEM simulation results indicate that wear on the left screw primarily occurs on the screw threads while wear on the right screw is concentrated at the junction between the screw threads and the bottom of the screw groove. The meshing region experiences the most severe wear due to the combined effects of shear forces and contact stress. Tribological experiments with a plate-on-disc tribometer reveal that adding cellulose with higher aspect ratios reduces friction coefficients. When cellulose has a high aspect ratio, it improves the alignment of wear scar cracks and cellulose molecular chains on the friction contact surface. This results in a gradual alignment of rod-shaped structural cellulose in the direction of frictional sliding, which reduces impact-spalling wear, micro-cutting wear, and scratching abrasion wear. Additionally, cellulose with higher aspect ratios can withstand higher rotational friction speeds during high-speed friction, forming an orientation transfer layer on the friction contact surface. This enhances surface lubrication and reduces abrasive wear and adhesive wear.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"34 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0