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Full-Text Articles in Polymer Science
On The Rheology Of Filled Polymers, Arkadii Leonov
On The Rheology Of Filled Polymers, Arkadii Leonov
Arkady I. Leonov
No abstract provided.
Non-Markovian Brownian Motion In A Viscoelastic Fluid, V. S. Volkov, Arkadii I. Leonov
Non-Markovian Brownian Motion In A Viscoelastic Fluid, V. S. Volkov, Arkadii I. Leonov
Arkady I. Leonov
A theory of non-Markovian translational Brownian motion in a Maxwell fluid is developed. A universal kinetic equation for the joint probability distribution of position, velocity, and acceleration of a Brownian particle is derived directly from the extended dynamic equations for the system. Unlike the extended Fokker-Planck equation which corresponds to Mori-Kubo generalized Langevin equation and provides only with calculations of one-time moments, the universal kinetic equation obtained gives complete statistical description of the process. In particular, an exact generalized Fokker-Planck equation in the velocity space valid for any time instant is derived for the free non-Markovian Brownian motion. It shows …
On A Self-Consistent Molecular Modeling Of Linear Relaxation Phenomena In Polymer Melts And Concentrated-Solutions, Arkadii Leonov
On A Self-Consistent Molecular Modeling Of Linear Relaxation Phenomena In Polymer Melts And Concentrated-Solutions, Arkadii Leonov
Arkady I. Leonov
This paper analyzes the linear version of the theory of ''relaxation interactions'' in polymer melts and concentrated polymer solutions proposed by Pokrovskii and Volkov in 1978, and which was subsequently developed later in many of their other publications; In these papers, the Brownian dynamics of a single macromolecule surrounded by other macromolecules was considered on the basis of the bead and spring model, and the environmental macromolecules were assumed to react as a viscoelastic liquid with an unknown relaxation spectrum. The key problem in this approach is the formulation of the self-consistency condition which delivers the equation for the unknown …
On 1d-Instabilities In Simple Shear And Extensional Flows As Predicted By Some Maxwell-Like Constitutive-Equations, Y. Kwon, Arkadii Leonov
On 1d-Instabilities In Simple Shear And Extensional Flows As Predicted By Some Maxwell-Like Constitutive-Equations, Y. Kwon, Arkadii Leonov
Arkady I. Leonov
One-dimensional (1D) instabilities, some of them of new type, were found in simple shear and simple elongation for Giesekus, Leonov, and Larson viscoelastic constitutive equations (CEs) with single relaxation mode. Whereas 1D instabilities in shear flow were found for all three CEs, only the Larson model manifested some ID instabilities (and even nonexistence of solution) in simple extensional flows.
The Effect Of Surface-Tension On Stretching Of Very Thin Highly Elastic Filaments, Arkadii Leonov
The Effect Of Surface-Tension On Stretching Of Very Thin Highly Elastic Filaments, Arkadii Leonov
Arkady I. Leonov
This paper deals with theoretical investigations of the extension of very thin highly elastic filaments as a function of fibrilar diameter. Some specific phenomena are predicted. If the diameter of the fibril is lower than a certain critical value, a nonmonotonous region appears on the stress–strain curve. In this region, a transition from slightly deformed to highly stretched (oriented) states occurs due to a special neck propagating along the fibril. A simple theoretical description of these phenomena is developed in terms of a given general high‐elastic dimensionless potential and two dimensionless parameters which characterize the external force and surface tension. …