Rheologica Acta最新文献_第6页

Elongational rheology of 2, 3 and 4 polymer stars connected by linear backbone chains 由线性骨架链连接的 2、3 和 4 聚合物星的拉伸流变性能

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-05-27 DOI: 10.1007/s00397-024-01455-x

Valerian Hirschberg, Max G. Schußmann, Marie-Christin Röpert, Anika Goecke, Manfred Wilhelm, Manfred H. Wagner

{"title":"Elongational rheology of 2, 3 and 4 polymer stars connected by linear backbone chains","authors":"Valerian Hirschberg, Max G. Schußmann, Marie-Christin Röpert, Anika Goecke, Manfred Wilhelm, Manfred H. Wagner","doi":"10.1007/s00397-024-01455-x","DOIUrl":"10.1007/s00397-024-01455-x","url":null,"abstract":"<div><p>We consider the elongational rheology of model polystyrene topologies with 2, 3 and 4 stars, which are connected by one (2-star or “Pom-Pom”), two (3-star) and three (4-star) linear backbone chains. The number of arms of each star varies from <i>q</i><sub><i>a</i></sub> = 3 to 24, the molecular weight of the arms from <i>M</i><sub><i>w,a</i></sub> = 25 kg/mol to 300 kg/mol, and the backbone chains from <i>M</i><sub><i>w,b</i></sub> = 100 kg/mol to 382 kg/mol. If the length of the arm is shorter than the length of the backbone, i.e. <i>M</i><sub><i>w,a</i></sub> < <i>M</i><sub><i>w,b</i></sub>, and despite the vastly different topologies considered, the elongational stress growth coefficient can be modeled by the Hierarchical Multi-mode Molecular Stress Function (HMMSF) model, based exclusively on the linear-viscoelastic characterization and a single nonlinear parameter, the dilution modulus. If the length of the arms of the stars is similar or longer than the length of the backbone chain (<i>M</i><sub><i>w,a</i></sub> ≥ <i>M</i><sub><i>w,b</i></sub>) connecting two stars, the impact of the backbone chain on the rheology vanishes and the elongational stress growth coefficient is dominated by the star topology showing similar features of the elongational stress growth coefficient as those of linear polymers.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 6","pages":"407 - 422"},"PeriodicalIF":2.3,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00397-024-01455-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141166492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Predicting the gravity-driven flow of power law fluids in a syringe: a rheological map for the IDDSI classification 预测注射器中幂律流体的重力驱动流动：IDDSI 分类流变图

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-05-22 DOI: 10.1007/s00397-024-01449-9

Rémi Lecanu, Guy Della Valle, Cassandre Leverrier, Marco Ramaioli

{"title":"Predicting the gravity-driven flow of power law fluids in a syringe: a rheological map for the IDDSI classification","authors":"Rémi Lecanu, Guy Della Valle, Cassandre Leverrier, Marco Ramaioli","doi":"10.1007/s00397-024-01449-9","DOIUrl":"10.1007/s00397-024-01449-9","url":null,"abstract":"<div><p>Food rheology is key to manage the swallowing safety of people affected by swallowing disorders (dysphagia). Simple approaches to assess the flow properties of texture-modified drinks are widely used, but relatively poorly understood. This study focuses on the International Dysphagia Diet Standardisation Initiative (IDDSI) flow test, adopted by caregivers worldwide. This test considers the gravity-driven flow in a vertical syringe. Newtonian liquids and non-Newtonian fluids obtained using a commercial starch-based thickener were considered in this study. An accurate theoretical description of the flow is proposed for Newtonian and power-law fluids considering the effect of fluid properties and of the syringe geometry. A rheological map is proposed, based on the results of several thousand simulations, to capture quantitatively the effect of rheological properties and density on the IDDSI classification, highlighting the important effect of the fluid density which is usually ignored. The sensitivity of the IDDSI results with respect to the syringe outlet diameter is discussed, as well as the different average shear rates at which different IDDSI levels are tested. The rheological map also shows quantitatively that different combinations of the fluid rheological properties and density can result in the same IDDSI classification, suggesting interesting directions for future clinical research.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 6","pages":"459 - 469"},"PeriodicalIF":2.3,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141109659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Experiments and numerical modelling of secondary flows of blood and shear-thinning blood analogue fluids in rotating domains 旋转域中血液和剪切稀化血液模拟流体二次流动的实验和数值建模

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-05-10 DOI: 10.1007/s00397-024-01447-x

Nathaniel S. Kelly, Harinderjit S. Gill, Andrew N. Cookson, Katharine H. Fraser

{"title":"Experiments and numerical modelling of secondary flows of blood and shear-thinning blood analogue fluids in rotating domains","authors":"Nathaniel S. Kelly, Harinderjit S. Gill, Andrew N. Cookson, Katharine H. Fraser","doi":"10.1007/s00397-024-01447-x","DOIUrl":"10.1007/s00397-024-01447-x","url":null,"abstract":"<div><p>The transition from concentric primary flow to non-tangential secondary flow of blood was investigated using experimental steady shear rheometry and numerical modelling. The aims were to: assess the difference in secondary flow in a Newtonian versus shear-thinning blood analogue; and measure the secondary flow in the blood. Both experiments and numerical modelling showed that the transition from primary to secondary flow was the same in a Newtonian fluid and a shear-thinning blood analogue. Experiments showed whole blood transitioned to secondary flow at lower modified Reynolds numbers than the Newtonian fluid; and transition was haematocrit dependent with higher RBC concentrations transitioning at lower modified Reynolds numbers. These results indicate that modelling blood as a purely shear-thinning fluid does not predict the correct secondary flow fields in whole blood; non-Newtonian effects beyond shear-thinning behaviour are influential, and incorporating effects such as multiphase contributions and viscoelasticity, yield stress and thixotropy is necessary.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 6","pages":"471 - 482"},"PeriodicalIF":2.3,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00397-024-01447-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140937905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Characterization and identification of gas invasion patterns in magnesium lithium phyllosilicate suspensions 植硅酸镁锂悬浮液中气体侵入模式的表征和识别

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-30 DOI: 10.1007/s00397-024-01453-z

Zhao Jin, Yixuan Hou, Xinzhe Que, Yongchao Zhou, Yiping Zhang

{"title":"Characterization and identification of gas invasion patterns in magnesium lithium phyllosilicate suspensions","authors":"Zhao Jin, Yixuan Hou, Xinzhe Que, Yongchao Zhou, Yiping Zhang","doi":"10.1007/s00397-024-01453-z","DOIUrl":"10.1007/s00397-024-01453-z","url":null,"abstract":"<div><p>In quasi-two-dimensional conditions, different invasion patterns can be observed when a fluid displaces another fluid with a higher viscosity. The transition from interfacial instability to fracture during gas invasion remained poorly understood, and classification criteria for different invasion patterns demanded further improvement. In this study, single-point compressed gas injection experiments were conducted in magnesium lithium phyllosilicate (MLPS) suspensions in a rectangular Hele-Shaw cell. Interestingly, with the increase of the injection pressure and the decrease of the concentration of MLPS suspension, the gas invasion pattern underwent a transition from viscous elastic fracture, elastic fracture, elastic viscous fingering to viscous fingering, in which viscous elastic fracture was observed for the first times. We detailly discuss the characteristics and occurrence conditions of each invasion pattern. Furthermore, by analyzing the velocity field of each invasion pattern, it is found that the relationship between the velocity direction around the gas and the gas growth direction varies with different invasion patterns. A simple and effective quantitative indicator is constructed to distinguish the different invasion patterns. Following the identification of invasion patterns, a further investigation was conducted into the relationship between invasion patterns and experimental conditions. By utilizing the relationships among injection conditions and material rheological properties, two dimensionless numbers, Bingham number and Weissenberg number, are conducted, which have an impact on the various invasion patterns and invasion process. A unified phase diagram based on the Bingham number and Weissenberg number was also proposed to incorporate the possible gas invasion patterns in the MLPS suspension.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 6","pages":"443 - 457"},"PeriodicalIF":2.3,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140833105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 mathematics of oscillatory recovery rheology with applications to experiments, the Cox-Merz rules, and the nonlinear modeling of common amplitude sweep behaviors 振荡恢复流变数学与实验应用、Cox-Merz 规则和常见振幅扫描行为的非线性建模

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-29 DOI: 10.1007/s00397-024-01448-w

Eric M. Burgeson, Simon A. Rogers

{"title":"The mathematics of oscillatory recovery rheology with applications to experiments, the Cox-Merz rules, and the nonlinear modeling of common amplitude sweep behaviors","authors":"Eric M. Burgeson, Simon A. Rogers","doi":"10.1007/s00397-024-01448-w","DOIUrl":"10.1007/s00397-024-01448-w","url":null,"abstract":"<div><p>Oscillatory shear tests are frequently used to determine viscoelastic properties of complex fluids. Both the amplitude and frequency of the input signal can be independently varied, allowing rheologists to probe a wide range of material responses. Historically, most oscillatory tests have focused on the measurement and application of the total strain. However, the total strain is a composite parameter consisting of recoverable and unrecoverable components. Use of only the total strain therefore provides an incomplete description of the rheology. In this work, we provide a mathematical derivation for the determination of the recoverable and unrecoverable components in steady-state linear viscoelastic oscillatory flows via a simple experimental procedure. The relationship between the total strain and its components is fully explored and challenged in the context of how rheologists define moduli and common rheological models. These relations are demonstrated via experimental measurements on model viscoelastic and viscoplastic materials: wormlike micelles and Carbopol 980. Additionally, we show how the derived mathematics fully details the conditions where the Cox-Merz rules are valid in terms of recovery rheology. Finally, we demonstrate how a thorough understanding of the strain components can be used to create a simple nonlinear model that reproduces all common amplitude sweep behaviors.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 6","pages":"423 - 442"},"PeriodicalIF":2.3,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140833106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Gelation of PU elastomers: rheological characterization for liquid additive manufacturing 聚氨酯弹性体的凝胶化：用于液体添加剂制造的流变特性分析

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-27 DOI: 10.1007/s00397-024-01451-1

Peng Wang, H. Henning Winter, Manfred H. Wagner, Dietmar Auhl

{"title":"Gelation of PU elastomers: rheological characterization for liquid additive manufacturing","authors":"Peng Wang, H. Henning Winter, Manfred H. Wagner, Dietmar Auhl","doi":"10.1007/s00397-024-01451-1","DOIUrl":"10.1007/s00397-024-01451-1","url":null,"abstract":"<div><p>Polyurethane (PU) is a versatile polymer with many applications in a wide range of products. A novel 3D printing technology called liquid additive manufacturing (LAM) extended its possibilities by generating PU elastomers with gradient properties in continuous processing. LAM, being a relatively new technique, has not been extensively researched, particularly in terms of the curing behavior of the liquid resin. In this work, we investigated the effect of composition on gelation time <i>t</i><sub>GP</sub> as measured by time-resolved mechanical spectroscopy (TRMS) and analyzed using the Winter–Chambon criterion with the assistance of the IRIS software. This method is more accurate than the previous approach, which involved time sweeps with a constant frequency. It was found that the gel time <i>t</i><sub>GP</sub> first decreased and then increased with increasing polyol ratio, ranging from 231 to 378 min. Furthermore, the crosslink densities of the different PU elastomers measured from the rheological and tensile tests were calculated and compared based on the theory of rubber elasticity. The crosslink density decreased with an increasing polyol ratio in both methods. However, the crosslink density values obtained from the rheological measurements were higher than those from the tensile tests. These findings demonstrate that adjusting the polyol ratio is an effective means of achieving gradient properties. The composition effects we measured offer valuable insights for the design of LAM–PU elastomers.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 5","pages":"397 - 406"},"PeriodicalIF":2.3,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00397-024-01451-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Melt strain hardening of polymeric systems filled with solid particles: review and supplementary experimental results 填充固体颗粒的聚合物体系的熔融应变硬化：综述和补充实验结果

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-26 DOI: 10.1007/s00397-024-01452-0

Helmut Münstedt

{"title":"Melt strain hardening of polymeric systems filled with solid particles: review and supplementary experimental results","authors":"Helmut Münstedt","doi":"10.1007/s00397-024-01452-0","DOIUrl":"10.1007/s00397-024-01452-0","url":null,"abstract":"<div><p>Melt strain hardening is an interesting characteristic property of the elongational flow of polymers. While strain hardening of many unmodified polymer melts has been widely discussed, a comprehensive presentation of the influence of particles on this property is missing. Using literature data and own measurements, the effects of solid particles of various geometries are compared. Micro-sized particles generally reduce melt strain hardening and may even lead to strain thinning. This behavior is postulated to be due to shear flow components around the particles and resulting shear thinning of the polymer matrices that reduces the resistance to flow. More complex is the influence of nano-sized fillers and layered silicate nanoparticles, in particular. Weakly exfoliated particles show effects similar to micro-fillers, but for strongly exfoliated silicates distinct strain hardening is observed that increases with decreasing elongational rate. This behavior is particularly pronounced for polymers modified with maleic anhydrides and thought to be related to electrostatic forces between exfoliated platelets of the silicates and polymer molecules hindering molecular motions.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 5","pages":"333 - 343"},"PeriodicalIF":2.3,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00397-024-01452-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140802274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Variable entanglement density constitutive rheological model for polymeric fluids 聚合物流体的可变纠缠密度构成流变模型

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-26 DOI: 10.1007/s00397-024-01444-0

Pavlos S. Stephanou

引用次数: 0

Role of plasticity in the universal scaling of shear-thickening dense suspensions 塑性在剪切增稠致密悬浮液的普遍缩放中的作用

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-15 DOI: 10.1007/s00397-024-01443-1

Sachidananda Barik, Akhil Mohanan, Sayantan Majumdar

{"title":"Role of plasticity in the universal scaling of shear-thickening dense suspensions","authors":"Sachidananda Barik, Akhil Mohanan, Sayantan Majumdar","doi":"10.1007/s00397-024-01443-1","DOIUrl":"10.1007/s00397-024-01443-1","url":null,"abstract":"<div><p>Increase in viscosity under increasing shear stress, known as shear thickening (ST), is one of the most striking properties of dense particulate suspensions. Under appropriate conditions, they exhibit discontinuous shear thickening (DST), where the viscosity increases dramatically and can also transform into a solid-like state due to shear-induced jamming (SJ). The microscopic mechanism giving rise to such interesting phenomena is still a topic of intense research. A phenomenological model proposed by Wyart and Cates shows that the proliferation of stress-activated interparticle frictional contacts can give rise to such striking flow properties. Building on this model, recent work proposes and verifies a universal scaling relation for ST systems where two different power-law regimes with a well-defined crossover point are obtained. Nonetheless, the difference in the nature of the flow in these two scaling regimes remains unexplored. Here, using rheology in conjugation with high-speed optical imaging, we study the flow and local deformations in various ST systems. We observe that with increasing applied stress, the smooth flow changes into a spatio-temporally varying flow across the scaling crossover. We show that such fluctuating flow is associated with intermittent dilatancy, shear-band plasticity, and fracture induced by system-spanning frictional contacts.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 4","pages":"291 - 300"},"PeriodicalIF":2.3,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140578632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Statistical analysis of identification of linear viscoelastic models 线性粘弹性模型识别的统计分析

IF 2.3 3区工程技术

Rheologica Acta Pub Date : 2024-04-12 DOI: 10.1007/s00397-024-01442-2

Tiago Lima de Sousa, Jéderson da Silva, Jucélio Tomas Pereira

{"title":"Statistical analysis of identification of linear viscoelastic models","authors":"Tiago Lima de Sousa, Jéderson da Silva, Jucélio Tomas Pereira","doi":"10.1007/s00397-024-01442-2","DOIUrl":"10.1007/s00397-024-01442-2","url":null,"abstract":"<div><p>Viscoelastic materials (VEMs) have gained increasing popularity for their ability to dampen vibrations in various structural applications in recent years. The mechanical characteristics of VEMs can be effectively described using constitutive models featuring both integer and fractional derivatives. This study examines the mechanical behavior of VEMs using fractional Zener models with four, five, and six parameters, as well as the generalized Maxwell model with 16 parameters, which relies on integer derivatives. To accomplish this, the study formulates an optimization problem with the aim of minimizing an error function defined by the quadratic relative distance between theoretical model responses and experimental data. Solving the optimization problem involves the use of a hybrid optimization technique, which combines genetic algorithms and non-linear programming. After obtaining optimal designs for each viscoelastic model, qualitative assessments demonstrate that all analytical models provide satisfactory fits to the experimental data. Subsequently, a statistical analysis employing Akaike’s Information Criterion is conducted to identify the models that best describe the mechanical behavior of the analyzed VEMs. In this quantitative evaluation encompassing all viscoelastic models, it is noted that the generalized Maxwell model with 16 terms produces a lower relative error and statistically outperforms the fractional Zener models only in a global analysis. However, in a temperature-by-temperature analysis, the GMM16 proves to be inferior to all fractional models. Furthermore, when focusing solely on the fractional models, the five-parameter Fractional Zener Model exhibits the best statistical fit to the experimental data.</p></div>","PeriodicalId":755,"journal":{"name":"Rheologica Acta","volume":"63 4","pages":"301 - 318"},"PeriodicalIF":2.3,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140578623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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