Macromolecular Reaction Engineering最新文献_第3页

Facile Synthesis of Well-Defined Polystyrene Through Microwave Assisted ARGET-ATRP 微波辅助靶- atrp快速合成定义良好的聚苯乙烯

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-06-17 Epub Date: 2026-03-29 DOI: 10.1002/mren.70016

Luis Antonio Arana Olivari, Kristín Ösp Benediktsdóttir, Katrín Marey Magnúsdóttir, Benjamín Ragnar Sveinbjörnsson

{"title":"Facile Synthesis of Well-Defined Polystyrene Through Microwave Assisted ARGET-ATRP","authors":"Luis Antonio Arana Olivari, Kristín Ösp Benediktsdóttir, Katrín Marey Magnúsdóttir, Benjamín Ragnar Sveinbjörnsson","doi":"10.1002/mren.70016","DOIUrl":"https://doi.org/10.1002/mren.70016","url":null,"abstract":"<div>\u0000 \u0000 Well defined polystyrene in varied sizes with polydispersity indices < 1.2 were obtained in reduced time using Microwave Assisted Activator Re-Generated by Electron Transfer Atom Transfer Radical Polymerization Reactions. The use of pre-synthetized Cu(II)Br/Me6TREN catalyst allows for rapid set-up of the reaction and addition of an excess of stannous octoate allows for oxygen tolerant conditions during the reaction set-up. The reaction mixture is stable for several days at room temperature, allowing for a series of polymerizations to be set up using an automatized polymerization reaction process. The reaction conditions were optimized in regards of the temperature (80°C–100°C), catalyst loading (0.15 equiv) and reaction times at 85°C (≤ 7 h). Well-controlled polymerizations are achieved for sizes up to 15 kDa, while maintaining polydispersity index values below 1.05. Kinetic comparisons between microwave irradiation and conventional heating methods show a higher apparent propagation rate constant while obtaining well-defined polymers. A norbornene-functionalized initiator allows us to obtain α, ω-end-chain functionalized polystyrene, providing potential expansion of applications in fields such as the synthesis of nanoparticles and polymer design.\u0000 </div>","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"20 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2026-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148269037","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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Free Radical Entry and Secondary Nucleation in Styrene Emulsion Polymerization: A DLVO Approach 苯乙烯乳液聚合中自由基进入和二次成核：DLVO方法

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-06-17 Epub Date: 2026-05-19 DOI: 10.1002/mren.70021

Andrea Molina-Estrada, Jesus Gracia Mora, Jorge Herrera-Ordonez

{"title":"Free Radical Entry and Secondary Nucleation in Styrene Emulsion Polymerization: A DLVO Approach","authors":"Andrea Molina-Estrada, Jesus Gracia Mora, Jorge Herrera-Ordonez","doi":"10.1002/mren.70021","DOIUrl":"https://doi.org/10.1002/mren.70021","url":null,"abstract":"A comprehensive model of free radical entry into particles during emulsion polymerization, recently reported in this journal, was modified to include the calculation of radical-particle interactions based on the DLVO theory as well as the simplified calculation of secondary nucleation. Electrostatic repulsion was found to play a crucial role, causing changes in the size of the predominant entering oligomer radical, whether due to variations in ionic strength or surfactant coverage (θ). As θ increases to ∼0.1, the energy barrier for the entry of water-soluble radicals raises sharply, causing their entry frequency (ρ) to decrease drastically and be controlled by diffusion. For θ>∼0.1, ρ becomes constant, and the predominant entering species are primary particles, whose formation is the rate-determining step. It was also found that the onset of secondary nucleation occurs at a critical θ value rather than a critical particle concentration. Based on the results obtained and their agreement with experimental data, key mechanistic aspects of radical entry into the system under study are proposed, which contradict several postulates of one of the most accepted theories of free radical entry. These findings also suggest that nucleation mechanisms above and below the surfactant's CMC should be revisited.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"20 3","pages":""},"PeriodicalIF":1.3,"publicationDate":"2026-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mren.70021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148268805","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}

引用次数: 0

Issue Information: Macromol. React. Eng. 2/2026 发布信息：Macromol。反应。Eng。2/2026

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-04-17 DOI: 10.1002/mren.70014

引用次数: 0

Process Modeling for Polyolefin Elastomer Polymerization with an Efficient Method for Kinetic Parameter Estimation 基于高效动力学参数估计的聚烯烃弹性体聚合过程建模

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-04-17 Epub Date: 2026-01-20 DOI: 10.1002/mren.70006

Muze Hong, Zhitao Li, Shanbao Lai, Qianqian Qiang, Jiajun Wang

引用次数: 0

Quantifying the Effects of Spatial Inhomogeneity in an Autoclave LDPE Reactor Using CFD 用CFD量化高压釜LDPE反应器中空间不均匀性的影响

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-04-17 Epub Date: 2026-04-02 DOI: 10.1002/mren.70015

Elijah Yoder, Wayne Strasser

{"title":"Quantifying the Effects of Spatial Inhomogeneity in an Autoclave LDPE Reactor Using CFD","authors":"Elijah Yoder, Wayne Strasser","doi":"10.1002/mren.70015","DOIUrl":"https://doi.org/10.1002/mren.70015","url":null,"abstract":"Fluid simulations are cost-effective and zero-waste alternatives for research and development of polymer reactors. However, many polymer-specific simulation software packages assume a homogeneous reactant mixture, overly simplifying the physics. Computational Fluid Dynamics (CFD) simulations provide more insight into this process but are difficult to utilize with detailed chemistry mechanisms. This work seeks to verify the implementation of free radical polymerization chemistry into a plant-scale CFD reactor model for Low-Density Polyethylene (LDPE) to investigate spatial gradients and their impact on the system. The process resulted in the most accurate CFD polymer reactor simulation to date, known to the authors, and sets a precedent for the verification and validation of other reactor models. It was found that the axial flow profiles formed distinct regions within the reactor wherein there were unmixed polymer properties. Significantly more variability was also found in the upstream-most reactor zone compared to a downstream zone, exemplified by a coefficient of variation of 447% in the former and 0.372% in the latter for the polydispersity index on a central plane of the reactor. Additionally, noticeable differences in properties were found between the inside and outside of the mixing shaft, which were only fractions of a percent different.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"20 2","pages":""},"PeriodicalIF":1.3,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mren.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148012023","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}

引用次数: 0

Issue Information: Macromol. React. Eng. 1/2026 发布信息：Macromol。反应。Eng。1/2026

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2026-02-17 DOI: 10.1002/mren.70008

引用次数: 0

Issue Information: Macromol. React. Eng. 6/2025 发布信息：Macromol。反应。Eng。6/2025

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2025-12-18 DOI: 10.1002/mren.70004

引用次数: 0

Advanced Polyethylene Wax via Zinc-Enhanced Metallocene Catalysis: Insights Into Molecular Weight Regulation Mechanisms 通过锌增强茂金属催化的先进聚乙烯蜡：对分子量调节机制的见解

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2025-10-25 DOI: 10.1002/mren.70003

Xiao Gui, Ying Liu, Shijia Wang, Qishun Guo, Xinpeng Xing, Wei Liu, Tao Jiang, Bing Yan

{"title":"Advanced Polyethylene Wax via Zinc-Enhanced Metallocene Catalysis: Insights Into Molecular Weight Regulation Mechanisms","authors":"Xiao Gui, Ying Liu, Shijia Wang, Qishun Guo, Xinpeng Xing, Wei Liu, Tao Jiang, Bing Yan","doi":"10.1002/mren.70003","DOIUrl":"https://doi.org/10.1002/mren.70003","url":null,"abstract":"<div>\u0000 \u0000 High-end polyethylene wax (PE-WAX) synthesized via ethylene polymerization is increasingly demanded for its superior physicochemical properties. Precise regulation of molecular weight and microstructure by metallocene catalysts remains a critical research focus. Herein, eight structurally distinct metallocene catalysts are systematically evaluated, with three optimal systems (M3, M4, M8) selected based on structure-activity relationships. Zinc-mediated chain transfer mechanisms and process optimization (Zn/Zr ratios, catalyst loading, temperature, pressure) are investigated through integrated experimental and density functional theory (DFT) studies. ZnEt2 addition effectively reduces molecular weights to the PE-WAX range (1000–10 000 g/mol), while revealing catalyst-dependent sensitivities: M8 demonstrates exceptional zinc responsiveness due to optimal electronic-steric synergy (smallest HOMO(Catalyst)–LUMO(ZnEt2) gap ΔE = 0.094 eV, longest Zr-C bond = 2.30 Å, shortest Zn-C distance = 4.84 Å), enabling efficient chain transfer. Pressure exerts significant control over molecular weight (M8: 7.8 × 103–2.26 × 104 g/mol) and branching density (1.3–9.1/1000C). DFT calculations confirm reduced kinetic barriers originate from synergistic electronic effects and spatial accessibility, establishing M8 as the premier catalyst for tunable PE-WAX production.\u0000 </div>","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"20 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146256557","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

The Chemical Modification of Graphite with Dopamine and Silane to Enhance Tribological Properties of PEK-C Matrix Composite Material 多巴胺和硅烷对石墨的化学改性提高PEK-C基复合材料的摩擦学性能

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2025-10-16 DOI: 10.1002/mren.70002

Zengwen Cao, Yu Zhang, Xin wang, Honge Fu, Guowei Jiang, Wencui Li

{"title":"The Chemical Modification of Graphite with Dopamine and Silane to Enhance Tribological Properties of PEK-C Matrix Composite Material","authors":"Zengwen Cao, Yu Zhang, Xin wang, Honge Fu, Guowei Jiang, Wencui Li","doi":"10.1002/mren.70002","DOIUrl":"https://doi.org/10.1002/mren.70002","url":null,"abstract":"<div>\u0000 \u0000 The compatibility between PEK-C and graphite has a significant impact on the ultimate composites performance. In this work, an effective and low-cost technique, combing bio-inspired dopamine polymerization and silane coupling agents grafting, was presented to improve the interfacial strength of graphite with PEK-C. As a result, the bonding strength of the composite was obviously superior to that of the non-treated and polydopamine-coated only, which was confirmed by SEM, DHR, and DSC experiments. Other characterizations indicated that the chemically modified graphite played the role of a toughening agent to improve the toughness of PEK-C/ graphite composites. Moreover, friction tests also displayed that the modified PEK-C/graphite composites exhibited enhanced tribological properties under different test conditions. When the linear velocity was 2.24 m/s, the dry friction coefficient of CS-6 was 0.1757, which was about 42% lower than the friction coefficient of the pure graphite-filled composite. In addition, the mass wear ratio of CS-6 composite was 0.054 wt.% under dry friction, which was 74% lower than CS-3. To sum up, the research not only proved the importance of interfacial strength to the frictional properties but also proposed a method to modify the interfacial interaction force of composites.\u0000 </div>","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"19 6","pages":""},"PeriodicalIF":1.3,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145779363","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

Issue Information: Macromol. React. Eng. 5/2025 发布信息：Macromol。反应。Eng。5/2025

IF 1.3 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2025-10-16 DOI: 10.1002/mren.70001

引用次数: 0