A Study of Viscoelastic Model of Polymers in Shear Flow Based on Molecular Dynamic Simulations

In this study, the rheological properties and physical significations of an incompressible viscoelastic (inCVE) the inCVE model was investigated by employing molecular dynamics calculations. Polypropylene (PP) and polystyrene (PS) polymers were selected as candidate materials, the corresponding cell models consisting of five chains of 80 (PP) and 30 (PS) units were built successively. The energy minimization and anneal treatment were launched to optimize the unfavorable structures. The periodic boundary condition, COMPASS force field and the Velocity-Verlet algorithm were employed to calculate the shear flow behavior of chains. The sample data were collected and fitted based on the Matlab platform, and the analysis of the variance (ANOVA) method was performed to determine the validity of the model. Experimental results reveal that the inCVE model matches well with the pseudo-plastic fluids. Compared with the Ostwald-de Waele power law model and Cross model, it is effective and robust, and exhibits a three-stage rheological characteristic. Moreover, it characterizes the stress yield, activation energy, temperature dependence and viscoelastic response of polymers.

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Melt elasticity and flow properties of polypropylene impact copolymer/polyolefin elastomer blends subjected to varied capillary extrusion conditions

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/14777606211019415 ◽

2021 ◽

pp. 147776062110194

Author(s):

Vishal Das ◽

AK Pandey ◽

DN Tripathi ◽

NE Prasad

Keyword(s):

Shear Flow ◽

Elastic Properties ◽

Flow Behavior ◽

Elongational Flow ◽

Theoretical Models ◽

Cross Model ◽

First Normal Stress Difference ◽

Polyolefin Elastomer ◽

Elongational Flows ◽

Capillary Extrusion

In present study, rheological properties of polypropylene impact copolymer (PPcp) and polyolefin elastomer (POE) blend melts were evaluated on a capillary rheometer under shear and elongational flows. The flow and melt elastic properties (die swell and first normal stress difference) studied at varied extrusion conditions were correlated with blend morphology and elastomer content by means of image analysis and theoretical models. Dispersed particle break-up and coalescence were observed to be influenced by POE content and the viscosities of the constituent polymers which were in turn affected by the capillary extrusion conditions (shear rate in particular). The blend melts demonstrated typical pseudoplastic behavior obeying Cross model under shear flow. The elongational flow also corroborated well with the shear flow behavior. All the blends illustrated prominent dependence of melt elastic properties on POE content and the capillary extrusion conditions. The melt elastic properties were also found to critically rely on the inter-particle distance of the POE phase.

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Shear flow behavior and dynamic viscosity of few-layer graphene nanofluids based on propylene glycol-water mixture

Journal of Molecular Liquids ◽

10.1016/j.molliq.2020.113875 ◽

2020 ◽

Vol 316 ◽

pp. 113875 ◽

Cited By ~ 1

Author(s):

Samah Hamze ◽

David Cabaleiro ◽

Thierry Maré ◽

Brigitte Vigolo ◽

Patrice Estellé

Keyword(s):

Shear Flow ◽

Propylene Glycol ◽

Dynamic Viscosity ◽

Flow Behavior ◽

Water Mixture ◽

Layer Graphene ◽

Few Layer Graphene

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Comparison of three rheological models of shear flow behavior studied on blood samples from post-infarction patients

Medical & Biological Engineering & Computing ◽

10.1007/s11517-007-0236-4 ◽

2007 ◽

Vol 45 (9) ◽

pp. 837-844 ◽

Cited By ~ 34

Author(s):

Anna Marcinkowska-Gapińska ◽

Jacek Gapinski ◽

Waldemar Elikowski ◽

Feliks Jaroszyk ◽

Leszek Kubisz

Keyword(s):

Shear Flow ◽

Flow Behavior ◽

Rheological Models ◽

Blood Samples

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Shear flow behavior of a dynamically symmetric polymeric bicontinuous microemulsion

Journal of Rheology ◽

10.1122/1.2750668 ◽

2007 ◽

Vol 51 (5) ◽

pp. 1027-1046 ◽

Cited By ~ 8

Author(s):

Ning Zhou ◽

Frank S. Bates ◽

Timothy P. Lodge ◽

Wesley R. Burghardt

Keyword(s):

Shear Flow ◽

Flow Behavior ◽

Bicontinuous Microemulsion

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Shear Flow Analysis of Nanosize Particle Flow Behavior Using Kinetic Theory

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.277-279.939 ◽

2005 ◽

Vol 277-279 ◽

pp. 939-944

Author(s):

Hae Ryung Kim ◽

Jaihyun Seu ◽

Hamid Arastoopour

Keyword(s):

Shear Flow ◽

Kinetic Theory ◽

Flow Behavior ◽

Flow Analysis ◽

Particle Diameter ◽

Particle Flow ◽

Particle Collision ◽

Simple Shear Flow ◽

Particle Force ◽

Nanosize Particle

Nanosize particle flow is significantly affected by inter-particle force. Due to the inter-particle force, the most significant characteristic of nanosize particle flow may become the formation of agglomerates or clusters which considerably affects the flow patterns. The formation of agglomerates or clusters results in a reduction in the number and an increase in the size of particles, both of which directly affect the frequency of inter-particle collisions and, in turn, the particle phase properties such as viscosity and pressure, as well as gas/particle drag force in gas/particle flow systems. In this present work, we focus our attention on the verification of nanosize particle flow behavior due to the formation of agglomerates or clusters under different fluctuation of flow and inelasticity of particle collision. By extending the application of the cohesive model using kinetic theory to nanosize particle flow system, we performed the homogeneous simple shear flow analysis using various fluctuation energy and restitution coefficient. The predicted flow properties, such as particle diameter growth, agreed well with the expected trends.

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A study of the transient shear flow behavior of the incompressible and isothermal thermoplastic polymer materials

Advances in Mechanical Engineering ◽

10.1177/1687814019852829 ◽

2019 ◽

Vol 11 (5) ◽

pp. 168781401985282

Author(s):

Donglei Liu ◽

Kun Fang

Keyword(s):

Shear Flow ◽

Flow Behavior ◽

Polymer Materials ◽

Thermoplastic Polymer ◽

Transient Shear Flow

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Dynamic simulations of individual macromolecules in oscillatory shear flow

Journal of Rheology ◽

10.1122/1.3072013 ◽

2009 ◽

Vol 53 (2) ◽

pp. 275-291 ◽

Cited By ~ 3

Author(s):

Dennis G. Thomas ◽

Ryan J. DePuit ◽

Bamin Khomami

Keyword(s):

Shear Flow ◽

Oscillatory Shear ◽

Dynamic Simulations ◽

Oscillatory Shear Flow

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Publisher's Note: Effect of the salt-induced micellar microstructure on the nonlinear shear flow behavior of ionic cetylpyridinium chloride surfactant solutions [Phys. Rev. E 95 , 032603 (2017)]

Physical Review E ◽

10.1103/physreve.95.049902 ◽

2017 ◽

Vol 95 (4) ◽

Author(s):

D. Gaudino ◽

R. Pasquino ◽

H. Kriegs ◽

N. Szekely ◽

W. Pyckhout-Hintzen ◽

...

Keyword(s):

Shear Flow ◽

Flow Behavior ◽

Cetylpyridinium Chloride ◽

Surfactant Solutions ◽

Nonlinear Shear

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Rheological Behavior of Seed Gum from Cassia fistula

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.818.16 ◽

2019 ◽

Vol 818 ◽

pp. 16-20

Author(s):

Wancheng Sittikijyothin ◽

Khanaphit Khumduang ◽

Keonakhone Khounvilay ◽

Rattanaphol Mongkholrattanasit

Keyword(s):

Shear Rate ◽

Flow Behavior ◽

Critical Concentration ◽

Shear Thinning ◽

Zero Shear Viscosity ◽

Specific Viscosity ◽

Cross Model ◽

Linear Slope ◽

Mechanical Spectra ◽

Seed Gum

The C. fistula gums in aqueous solutions clearly exhibited shear-thinning flow behavior at high shear rate, however, at higher concentrations, pronounced shear thinning was observed. The value of zero shear viscosity [h0] was predicted by fitting Cross model. A plotting of specific viscosity at zero shear rate (hsp0) against coil overlap parameter (C[h]) was shown the linear slope of dilute and simi-dilute as 1.43 and 4.10, respectively, which found the critical concentration (C*) about 7.08/[h]. While, the mechanical spectra in the linear viscoelastic region of gum solutions showed the typical shape for macromolecular solutions.

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