Macromolecular Reaction Engineering最新文献_第10页

Modeling of Diffusive Transport of Polymers Moments Using Limiting Cases of the Maxwell–Stefan Model 利用Maxwell - Stefan模型的极限情况对聚合物矩的扩散输运建模

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-11-10 DOI: 10.1002/mren.202200045

Stefan Welzel, Winfried Säckel, Ulrich Nieken

引用次数: 1

Estimation of Reactivity Ratios for Olefin Polymerization Catalysts—On the Importance of Thermodynamics 烯烃聚合催化剂反应性比的估计——论热力学的重要性

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-11-02 DOI: 10.1002/mren.202200053

Niyi B. Ishola, Timothy F. L. McKenna

引用次数: 0

Impact of Process Poisons on the Performance of Post-Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization 工艺毒物对邻苯二甲酸酯后负载Ziegler - Natta催化剂气相丙烯聚合性能的影响

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-11-02 DOI: 10.1002/mren.202200049

Abdulrahman Albeladi, Akhlaq Moman, Timothy F. L. McKenna

{"title":"Impact of Process Poisons on the Performance of Post-Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization","authors":"Abdulrahman Albeladi, Akhlaq Moman, Timothy F. L. McKenna","doi":"10.1002/mren.202200049","DOIUrl":"10.1002/mren.202200049","url":null,"abstract":"The impact of common process catalyst poisons on the performance of a 6th generation Ziegler–Natta catalysts during the gas phase polymerization of propylene are examined using two approaches: introducing propylene without purification, or with one or two sets of purification columns, and by introducing carbon dioxide (CO2), oxygen (O2), water (H2O), methanol (CH3OH), ethyl acetate (C4H8O2) and dimethyl sulfoxide (C2H6SO) during the polymerization. As expected, purification columns increases the catalyst activity significantly, slightly reduce catalyst decay. Injecting TiBA during the reaction leads to an activity increase. The addition of two full sets of columns substantially increased the repeatability of polymerization reactions. The power of deactivation of poisons injected during the polymerization reaction is: O2 > CO2 > CH3OH > C2H6SO > C4H8O2 > H2O. Adding CO2, O2, and CH3OH resulted in a progressive decrease in molecular weight while almost no effect is observed with H2O. However, C4H8O2, and C2H6SO resulted in a mild increase in molecular weight. Additionally, the effects on crystallinity and stereoregularity are similar where CO2, O2, H2O and CH3OH caused a progressive decrease while C4H8O2 and C2H6SO resulted in a mild increase, indicating some isotacticity control by these two poisons.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43344524","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

β-Myrcene Coordination Polymerization: Experimental and Kinetic Modeling Study β-月桂烯配位聚合反应的实验与动力学模型研究

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-10-25 DOI: 10.1002/mren.202200041

Marília Caroline C. de Sá, Teresa Córdova, Príamo Albuquerque Melo Jr., Ramón Díaz de León, José Carlos Pinto

{"title":"β-Myrcene Coordination Polymerization: Experimental and Kinetic Modeling Study","authors":"Marília Caroline C. de Sá, Teresa Córdova, Príamo Albuquerque Melo Jr., Ramón Díaz de León, José Carlos Pinto","doi":"10.1002/mren.202200041","DOIUrl":"10.1002/mren.202200041","url":null,"abstract":"The present work presents phenomenological models to describe the coordination polymerization of β-myrcene using the Ziegler–Natta catalyst system composed by neodymium versatate (NdV3), diisobutylaluminum hydride (DIBAH), and dimethyldichlorosilane. The kinetic parameters required to simulate the reactions are estimated, and the amount of DIBAH used as a chain transfer agent (CTA) is obtained by a data reconciliation strategy since it can participate in side reactions. Several experiments are performed at different conditions to evaluate the impact of key operation variables on the control of monomer conversion and average molar masses. It is shown that the initial NdV3, β-myrcene, and DIBAH concentrations exert strong influences on the course of the polymerization. The kinetic mechanism of Coordinative Chain Transfer Polymerization (CCTP) fits well with the data of final average molar masses and monomer conversion, while the dynamic trajectories of these variables are fitted better by kinetic mechanisms of more conventional coordination polymerizations, considering site deactivation and termination by chain transfer. In all cases, the proposed models are able to predict the experimental data well after successful parameter estimation and reconciliation of CTA concentrations, indicating that the kinetic mechanism can be characterized by different kinetic regimes.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42193924","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: 1

Masthead: Macromol. React. Eng. 5/2022 刊头：Macromol.React.Eng.5/2022

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-10-19 DOI: 10.1002/mren.202270010

引用次数: 0

Macromol. React. Eng. 5/2022 Macromol.React.Eng.5/2022

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-10-19 DOI: 10.1002/mren.202270009

引用次数: 0

A Novel PolyHIPE-like Catalyst for Esterification Reactions: on the Synthesis of Sulfonated Poly(styrene-co-n-acylglycerol) and its Use for Efficient Conversion of Oleic Acid to Methyl Oleate 一种新型类聚聚乙烯酯化催化剂:磺化聚苯乙烯- co - n -酰基甘油的合成及其在油酸高效转化为油酸甲酯中的应用

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-10-18 DOI: 10.1002/mren.202200055

Alan Thyago Jensen, Rossano Gambetta, Fabricio Machado

{"title":"A Novel PolyHIPE-like Catalyst for Esterification Reactions: on the Synthesis of Sulfonated Poly(styrene-co-n-acylglycerol) and its Use for Efficient Conversion of Oleic Acid to Methyl Oleate","authors":"Alan Thyago Jensen, Rossano Gambetta, Fabricio Machado","doi":"10.1002/mren.202200055","DOIUrl":"10.1002/mren.202200055","url":null,"abstract":"The current work describes the synthesis of a new polyHIPE-like sulfonated poly(styrene-co-n-acylglycerol) and its use as an efficient heterogeneous catalyst to convert oleic acid into methyl oleate in esterification reactions. This new environmentally friendly polymer incorporates n-acylglycerol macromonomer as a versatile strategy for glycerol valorization. Macroporous micrometric polymer particles are synthesized through suspension polymerization process without using porogenic agents. polyHIPE-like copolymers formed with different feed compositions of styrene and n-acylglycerol are chemically modified via sulfonation reactions to form a highly efficient catalyst for esterification of oleic acid to methyl oleate, exhibiting conversions lying in the interval from 52% to 96%, depending mainly on the amount of n-acylglycerol macromonomer into the copolymer chains. The experimental results indicate the great potential of this new heterogeneous catalyst based on modified poly(styrene-co-n-acylglycerol) to be successfully employed in esterification reactions of vegetable oils intended for the production of long chain alkyl esters of carboxylic acids, widely used as biofuels.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46304532","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

Thin Organic-Inorganic Anti-Fouling Hybrid-Films for Microreactor Components 微反应器组件用有机-无机防污复合薄膜

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-09-20 DOI: 10.1002/mren.202200043

Vanessa Neßlinger, Stefan Welzel, Florian Rieker, Dennis Meinderink, Ulrich Nieken, Guido Grundmeier

{"title":"Thin Organic-Inorganic Anti-Fouling Hybrid-Films for Microreactor Components","authors":"Vanessa Neßlinger, Stefan Welzel, Florian Rieker, Dennis Meinderink, Ulrich Nieken, Guido Grundmeier","doi":"10.1002/mren.202200043","DOIUrl":"10.1002/mren.202200043","url":null,"abstract":"Deposit formation and fouling in reactors for polymer production and processing especially in microreactors is a well-known phenomenon. Despite the flow and pressure loss optimized static mixers, fouling occurs on the surfaces of the mixer elements. To improve the performance of such parts even further, stainless steel substrates are coated with ultra-thin films which have low surface energy, good adhesion, and high durability. Perfluorinated organosilane (FOTS) films deposited via chemical vapor deposition (CVD) are compared with FOTS containing zirconium oxide sol-gel films regarding the prevention of deposit formation and fouling during polymerization processes in microreactors. Both film structures led to anti-adhesive properties of microreactor component surfaces during aqueous poly(vinylpyrrolidone) (PVP) synthesis. To determine the morphology and surface chemistry of the coatings, different characterization methods such as X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy as well as microscopic methods such as field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM) are applied. The surface free energy and wetting properties are analyzed by means of contact angle measurements. The application of thin film-coated mixing elements in a microreactor demonstrates a significant lowering in pressure increase caused by a reduced deposit formation.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mren.202200043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47211946","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: 4

Fast Catalyst Ratio Estimate in Gas Phase Polyethylene Dual Catalyst System 气相聚乙烯双催化剂体系中快速催化剂比率的估算

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-09-17 DOI: 10.1002/mren.202200029

Jay L. Reimers, Hsu Chiang, Jun Shi

{"title":"Fast Catalyst Ratio Estimate in Gas Phase Polyethylene Dual Catalyst System","authors":"Jay L. Reimers, Hsu Chiang, Jun Shi","doi":"10.1002/mren.202200029","DOIUrl":"10.1002/mren.202200029","url":null,"abstract":"One approach used in the industry to improve the properties of polyethylene is to use multi-reactor with a single catalyst or multiple catalysts in a single reactor. In the latter case, two catalysts with distinct kinetics are selected to achieve the desired product properties. Such mixed catalyst systems enable tailored and advantageous properties at the cost of more challenging process control, because the ratio of the two catalysts serves as an additional manipulated variable. A fast method to estimate the ratio of active catalysts using headspace gas chromatography measurements is proposed here. In this method, a small perturbation in the feed rate is introduced to induce transient responses in the gas phase concentration. Ideally, with known responses from each individual catalyst, the active catalyst ratio can be estimated. To demonstrate this concept, a process model is developed in Aspen Plus. A set of dynamic simulation is performed to understand the responses of each catalyst and the mixed catalyst system, to changes in feed comonomer concentration. The results demonstrate that this method has significantly faster responses compared to feedback from bulk polymer properties and induces minimal process upset or product off-spec due to small perturbations in a short period of time.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49025395","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

Assessing the Downstream Contamination of Chemically Recycled Ethylene Feed Streams on the Kinetic Behavior of Ziegler-Natta Catalysts and Microstructural Properties of HDPE and LLDPE 化学回收乙烯进料流下游污染对Ziegler-Natta催化剂动力学行为和HDPE和LLDPE微观结构性能的评估

IF 1.5 4区工程技术

Macromolecular Reaction Engineering Pub Date : 2022-09-01 DOI: 10.1002/mren.202200042

Daniel Christian Pernusch, Christian Paulik, Matthias Mastalir, Wolfgang Hofer

{"title":"Assessing the Downstream Contamination of Chemically Recycled Ethylene Feed Streams on the Kinetic Behavior of Ziegler-Natta Catalysts and Microstructural Properties of HDPE and LLDPE","authors":"Daniel Christian Pernusch, Christian Paulik, Matthias Mastalir, Wolfgang Hofer","doi":"10.1002/mren.202200042","DOIUrl":"10.1002/mren.202200042","url":null,"abstract":"The sustainability of consumer materials, such as plastics, belongs to the most important aspect of eco-efficiency analyses. Besides mechanical recycling, chemical recycling represents an interesting waste management pathway. In theory, this technique does not rely on single-grade feedstock to maintain product quality. However, cross-contamination of feedstocks potentially leads to above-specification impurities in obtained pyrolysis oils. This study investigates the potential downstream poisoning of a fourth-generation Ziegler-Natta catalyst, using selected model poisons at high (worst-case) concentrations. With experimental and computational analysis, economic feasibility factors such as catalyst activity and microstructural properties are evaluated during the synthesis of high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE). Noticeable effects on the catalyst activity can be observed when the poison interacts with the co-catalyst, whereas a lower impact is observed for interactions with the activated catalyst-co-catalyst complex. Molecular weight distribution (MWD) and comonomer composition distribution (CCD) modeling highlighted marginal to no polymer property changes caused by contaminants. Combined with the applicability of pyrolysis post-treatments, these observations show that chemical recycling can be a promising technique for post-consumer plastic waste treatment.","PeriodicalId":18052,"journal":{"name":"Macromolecular Reaction Engineering","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mren.202200042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48484175","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: 1