Exploring the nonlinear viscoelasticity of a high viscosity silicone oil with LAOS

Kokuti, Z.; Völker-Pop, L.; Brandstätter, Martin; Kokavecz, Janos; Ailer, P.; Palkovics, László; Szabó, Gábor; Czirják, Attila

doi:10.3933/applrheol-26-14289

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…39 The magnitude of the ratio between the third and first harmonic Chebyshev coefficients, i.e., e 3 /e 1 and ν 3 /ν 1 , characterizes the nonlinearity in the sample as the higher magnitude indicates increasing nonlinearity. 63,64 In our experiments, the highest strain amplitude considered was 50%, and the corresponding Lissajous curves for all salt concentrations are shown in Figure 6. Here, the Lissajous curves were more distorted for low salt concentration, in which the LVE region was smaller.…”

Section: Degree Of Deacetylation (Dd)mentioning

confidence: 96%

Effects of Salt on Phase Behavior and Rheological Properties of Alginate–Chitosan Polyelectrolyte Complexes

et al. 2023

View full text Add to dashboard Cite

Oppositely charged polyelectrolytes often form polyelectrolyte complexes (PECs) due to the association through electrostatic interactions. Obtaining PECs using natural, biocompatible polyelectrolytes is of interest in the food, pharmaceutical, and biomedical industries. In this work, PECs were prepared from two biopolymers, positively charged chitosan and negatively charged alginate. We investigate the changes in the structure and properties of PECs by adding sodium chloride (salt doping) to the system. The shear modulus of PECs can be tuned from ∼10 to 10 4 Pa by changing the salt concentration. The addition of salt led to a decrease in the water content of the complex phase with increasing shear modulus. However, at a very high salt concentration, the shear modulus of the complex phase decreased but did not lead to the liquid coacervate formation, typical of synthetic polyelectrolytes. This difference in phase behavior has likely been attributed to the hydrophobicity of chitosan and long semiflexible alginate and chitosan chains that restrict the conformational changes. Large amplitude oscillatory shear experiments captured nonlinear responses of PECs. The compositions of the PECs, determined as a function of salt concentration, signify the preferential partitioning of salt into the complex phase. Small-angle X-ray scattering of the salt-doped PECs indicates that the Kuhn length and radius of the alginate−chitosan associated structure qualitatively agree with the captured phase behavior and rheological data. This study provides insights into the structure−property as a function of salt concentration of natural polymer-based PECs necessary for developing functional materials from natural polyelectrolytes.

show abstract

Section: Degree Of Deacetylation (Dd)mentioning

confidence: 96%

Effects of Salt on Phase Behavior and Rheological Properties of Alginate–Chitosan Polyelectrolyte Complexes

et al. 2023

View full text Add to dashboard Cite

show abstract

Temperature-Dependent Viscosity Model for Silicone Oil and Its Application in Viscous Dampers

2021

View full text Add to dashboard Cite

Silicone fluids belong to the group of pseudoplastic non-Newtonian fluids with complex rheological characteristics. They are considered in basic and applied researches and in a wide range of industrial applications due to their favorable physical and thermal properties. One of their specific field of applications in the automotive industry is the working fluid of viscous torsional vibration dampers. For numerical studies in the design and development phase of this damping product, it is essential to have thorough rheological knowledge and mathematical description about the silicone oil viscosity. In the present work, adopted rheological measurement results conducted on polydimethylsiloxane manufactured by Wacker Chemie with initial viscosity of 1000 Pas (AK 1 000 000 STAB silicone oil) are processed. As a result of the parameter identification by nonlinear regression, the temperature-dependent parameter curves of the Carreau–Yasuda non-Newtonian viscosity model are generated. By implementing these parameter sets into a Computational Fluid Dynamics (CFD) software, a temperature- and shear-rate-dependent viscosity model of silicone fluid was tested, using transient flow and thermal simulations on elementary tube geometries in the size range of a real viscous torsional vibration damper’s flow channels and filling chambers. The numerical results of the finite volume method provide information about the developed flow processes, with especial care for the resulted flow pattern, shear rate, viscosity and timing.

show abstract

Non-Linear Rheological Properties of Soft Wheat Flour Dough at Different Stages of Farinograph Mixing

Yazar

Duvarcı

Tavman

et al. 2016

View full text Add to dashboard Cite

Exploring the nonlinear viscoelasticity of a high viscosity silicone oil with LAOS

Cited by 3 publications

References 0 publications

Effects of Salt on Phase Behavior and Rheological Properties of Alginate–Chitosan Polyelectrolyte Complexes

Effects of Salt on Phase Behavior and Rheological Properties of Alginate–Chitosan Polyelectrolyte Complexes

Temperature-Dependent Viscosity Model for Silicone Oil and Its Application in Viscous Dampers

Non-Linear Rheological Properties of Soft Wheat Flour Dough at Different Stages of Farinograph Mixing

Contact Info

Product

Resources

About