Macromolecular Reaction Engineering最新文献_第7页

Branched Comonomers in LLDPE—Influence of Short Chain Branch Shape on Crystallinity Lldpe中的支链共聚单体——短链支形对结晶度的影响

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-07-04 DOI: 10.1002/mren.202300035

Lukas Göpperl, Roberta Cipullo, Clemens Schwarzinger, Christian Paulik

引用次数: 0

Temperature-Optimized Synthesis of SiO2-Reinforced N-(Alkyl)Acrylamide-Based Semi-IPN Hybrid Gels Functionalized with Methacrylic Acid Units 甲基丙烯酸功能化SiO2增强N-（烷基）丙烯酰胺基半互穿网络杂化凝胶的温度优化合成

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-06-16 DOI: 10.1002/mren.202370005

Birgül Kalkan, Merve Mocan, Nermin Orakdogen

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Masthead: Macromol. React. Eng. 3/2023 刊头：Macromol。反应工程3/2023

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-06-16 DOI: 10.1002/mren.202370006

引用次数: 0

Effects of Internal Electron Donor on Distribution and Reactivity of Active Centers in Ethylene/1-Hexene Copolymerization with MgCl2-Supported Ziegler-Natta Catalyst 内部电子供体对MgCl2负载Ziegler-Natta催化剂催化乙烯/1-己烯共聚反应活性中心分布和反应活性的影响

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-06-14 DOI: 10.1002/mren.202300033

Tao Xu, Zhisheng Fu, Zhiqiang Fan

{"title":"Effects of Internal Electron Donor on Distribution and Reactivity of Active Centers in Ethylene/1-Hexene Copolymerization with MgCl2-Supported Ziegler-Natta Catalyst","authors":"Tao Xu, Zhisheng Fu, Zhiqiang Fan","doi":"10.1002/mren.202300033","DOIUrl":"10.1002/mren.202300033","url":null,"abstract":"Ethylene/1-hexene copolymerization with two MgCl2-supported Ziegler-Natta catalysts containing no internal electron donor or diethylphthalate (DEP) is conducted for different polymerization time . Effects of DEP on active center distribution are studied by fractionating each copolymer sample into boiling n-heptane soluble (C7-sol) and insoluble (C7-ins) fractions, and counting the number of active centers in the copolymer fractions . The main effect of introducing DEP in the catalyst are reduction in the Ti content and significant increase in the proportion of active centers producing C7-ins fraction. The propagation rate constants of ethylene insertion (kpE) and 1-hexene insertion (kpH) are respectively estimated by linear fitting/extrapolating the change of apparent propagation rate constants (kpi)a with polymer yield according to a simplified multi-grain particle model. In both catalysts, kpE in the C7-ins fraction is 9–12 times larger than that in the C7-sol fraction, and kpH in the C7-ins fraction is 3–4 times larger than that in the C7-sol fraction. The two groups of active centers have distinctly different catalytic properties. Introducing DEP reduced the kpE and kpH values and the extent of diffusion limitation . In summary, addition of electron donor in MgCl2-supported Z-N catalyst significantly changed the active center distribution and catalytic properties of its two groups of active centers.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"17 6","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43410403","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

Toward Reactive Processing of Polyamide 6 Based Blends with Polyethylene Grafted with Maleic Anhydride and Acrylic Acid: Effect of Functionalization Degree 马来酸酐和丙烯酸接枝聚乙烯系聚酰胺6基共混物的反应工艺研究&功能化程度的影响

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-06-13 DOI: 10.1002/mren.202300031

Carlos Bruno Barreto Luna, Eduardo da Silva Barbosa Ferreira, Anna Raffaela de Matos Costa, Yeda Medeiros Bastos de Almeida, João Baptista da Costa Agra de Melo, Edcleide Maria Araújo

{"title":"Toward Reactive Processing of Polyamide 6 Based Blends with Polyethylene Grafted with Maleic Anhydride and Acrylic Acid: Effect of Functionalization Degree","authors":"Carlos Bruno Barreto Luna, Eduardo da Silva Barbosa Ferreira, Anna Raffaela de Matos Costa, Yeda Medeiros Bastos de Almeida, João Baptista da Costa Agra de Melo, Edcleide Maria Araújo","doi":"10.1002/mren.202300031","DOIUrl":"10.1002/mren.202300031","url":null,"abstract":"The reactivity of different polyethylene modifiers based on acrylic acid (AA) and maleic anhydride (MA) with polyamide 6 (PA6) is investigated, using several degrees of functionalization. The polymer blends are processed in an internal mixer and injection molded. Mechanical, rheological, infrared spectroscopy, thermal, thermomechanical properties, and morphology are evaluated. The torque rheometry results show that higher functionalization degrees favored a high reactivity with PA6. As a consequence, there is an increase in the viscosity of the polymer blends, which is reflected in the reduction of the melt flow index (MFI), compared to PA6. High impact strength and elongation at break properties confirm the blends' compatibility. The elastic modulus and the tensile strength maintain high values, suggesting a balance of mechanical properties. In addition, the polymer blends' heat deflection temperature (HDT) and thermal stability properties are comparable to neat PA6. The morphology obtained by scanning electron microscopy show dispersed and refined particles in the PA6 matrix, indicating stabilization at the interface. Incorporating only 10% of high-density polyethylene grafted with acrylic-acid (HDPE-g-AA) is very efficient in optimizing the properties of PA6, contributing to broadening the range of applications for the processing industry.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"17 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47467044","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: 4

Flow Activation Energy Estimation by Thermo-Rheological Method 热流变法估算流动活化能

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-05-25 DOI: 10.1002/mren.202300019

Qiao Lin, Nadine Allanic, Manuel Girault, Pierre Mousseau

引用次数: 0

An Adaptive Soft Sensor for On-Line Monitoring the Mass Conversion in the Emulsion Copolymerization of the Continuous SBR Process 用于连续SBR过程中乳液共聚质量转化在线监测的自适应软传感器

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-05-24 DOI: 10.1002/mren.202300025

Carlos I. Sanseverinatti, Mariano M. Perdomo, Luis A. Clementi, Jorge R. Vega

{"title":"An Adaptive Soft Sensor for On-Line Monitoring the Mass Conversion in the Emulsion Copolymerization of the Continuous SBR Process","authors":"Carlos I. Sanseverinatti, Mariano M. Perdomo, Luis A. Clementi, Jorge R. Vega","doi":"10.1002/mren.202300025","DOIUrl":"10.1002/mren.202300025","url":null,"abstract":"Soft sensors (SS) are of importance in monitoring polymerization processes because numerous production and quality variables cannot be measured online. Adaptive SSs are of interest to maintain accurate estimations under disturbances and changes in operating points. This study proposes an adaptive SS to online estimate the mass conversion in the emulsion copolymerization required for the production of Styrene-Butadiene rubber (SBR). The SS includes a bias term calculated from sporadic laboratory measurements. Typically, the bias is updated every time a new laboratory report becomes available, but this strategy leads to unnecessarily frequent bias updates. The SS includes a statistic-based tool to avoid unnecessary bias updates and reduce the variability of the bias with respect to classical approaches. A control chart (CC) for individual determinations combined with an algorithmic Cusum is used to monitor the statistical stability of the average prediction error. The adaptive SS enables a bias update only when a loss of said statistical stability is detected. Several bias update methods are tested on a simulated industrial train of reactors for the latex production in the SBR process. The best results are obtained by combining the proposed CC-based approach with a previously developed Bayesian bias update strategy.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"17 5","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43574293","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

Synthesis of Vinyl Acetate Monomer Over PdCu Alloys: The Role of Surface Oxygenation in the Reaction Path 在PdCu合金上合成醋酸乙烯单体:表面氧化在反应路径中的作用

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-05-19 DOI: 10.1002/mren.202300016

Alberth Renne Gonzalez Caranton, Martin Schmal, Noemi Raquel Checca Huaman, José Carlos da Silva Pinto

{"title":"Synthesis of Vinyl Acetate Monomer Over PdCu Alloys: The Role of Surface Oxygenation in the Reaction Path","authors":"Alberth Renne Gonzalez Caranton, Martin Schmal, Noemi Raquel Checca Huaman, José Carlos da Silva Pinto","doi":"10.1002/mren.202300016","DOIUrl":"10.1002/mren.202300016","url":null,"abstract":"This work uses sol–gel and sonochemical methods to prepare bimetallic PdCu catalysts supported on modified ZrO2 with Ti and Al. The catalysts are tested for vinyl acetate synthesis from ethylene, acetic acid, and oxygen, varying the reaction temperature for two catalysts prepared, which show higher activity. Catalysts characterization results show bimetallic species and distort alloys with a dispersed distribution of active metal onto the support. The in situ reaction by DRIFT-MS identifies the surface formation of main intermediates like palladium acetate monomers and mono and bidentate intermediates, associated to vinyl acetate formation, like vinyl hydrogenated species over PdCu. Finally, this behavior will be attributed to the bimetallic distortions of PdCu samples, provided by interaction effects between PdCu and supports, indicating a more exposition of PdCu species suitable for the reaction, according to high-resolution transmission microscopy electron microscopy results for PdCu/ZrTi sample. Thus, this sample exhibits a minimal formation of sub-products and catalytic stability for 18 hh. These results evidence the participation of hydroxyls and oxygen vacancies of the catalyst in the catalytic reaction measured in situ, monitoring the products formed at the reactor outlet. Finally, it is proposed a reaction pathway as a function of reaction conditions.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"17 4","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43935396","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

Generalization and Evaluation of the Analytical Solution of Intraparticle Diffusion Models in Finite Batch Adsorption 有限批吸附颗粒内扩散模型解析解的推广与评价

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-05-18 DOI: 10.1002/mren.202300018

Gabriel Miglioranza, Marcio Schwaab

{"title":"Generalization and Evaluation of the Analytical Solution of Intraparticle Diffusion Models in Finite Batch Adsorption","authors":"Gabriel Miglioranza, Marcio Schwaab","doi":"10.1002/mren.202300018","DOIUrl":"https://doi.org/10.1002/mren.202300018","url":null,"abstract":"In this paper, a detailed description of particle adsorption/diffusion model in batch systems is presented. The phenomenological equations are based on a mechanism combining mass transfer by convection from bulk phase to particle surface, intraparticle mass diffusion and equilibrium adsorption processes. The change of bulk and particle concentration is modeled through differential mass balance equations, leading to a system of one ordinary differential equation and one partial differential equation. When adsorption equilibrium follows a linear relationship, this system of equations can be solved by the Laplace transform method. The purpose of this paper is the development of a generalized analytical solution, that is rewritten specifically for each of the traditional particle shapes: slab, cylinder, and sphere. Finally, this analytical solution is evaluated through several simulations in different batch conditions and compared to simulated experimental data, showing the capability of this analytical solution to predict batch adsorption processes when adsorbate concentration is low. This result clearly indicates the feasibility of applying the analytical solution presented in this paper, which is based on phenomenological concepts, to describe the adsorption kinetics of processes, when the linear isotherm can be considered adequate to represent the adsorption equilibrium.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":"17 4","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50146033","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

Generalisation and Evaluation of the Analytical Solution of Intraparticle Diffusion Models in Finite Batch Adsorption 有限批吸附中颗粒内扩散模型解析解的推广与评价

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2023-05-18 DOI: 10.1002/mren.202300018

Gabriel Miglioranza, Marcio Schwaab

引用次数: 0