The Foundations of Rheology
Authors: Prof. Dr. Alexander Ya. Malkin
ISBN 978-1-77467-046-0 (hard copy)
Published: 2025
Pages: 344 + vi
Figures 377
This book is for anyone who could not understand rheology, the science of the flow of natural and artificial liquids, because of its extensive jargon and infestation with complex formulas, which cloud the real meaning and potential of rheology, but those who really wish to understand and (possibly) use it in his work and life. In this book, rheology appears as one of the techniques that help enhance our knowledge of chemistry, physics, material science, applied technology, and many other similar fields. Learning rheology is no longer restricted to a selected few but is an enchanting story of human inventiveness and perception – due to the understanding and skills of conveying this complex information by the author of this book.
The book presents the main theoretical concepts of rheology illustrated with experimental data, and a discussion of the practical applications of the results of studies of the flow of many real liquids encountered in everyday life, medicine, pharmaceutical production, engineering, process technology, building construction and their decoration, cosmetics, marine applications, and many other disciplines which rely on rheological measurements and data.
The author is one of the most recognized world rheologists, who, in his long practice, developed courses that are comprehensive and easy to understand. The main goal of this book is to serve the needs of experienced practitioners and novices, university professors and students, as well as designers of new products and those who work with and adapt these products to everyday applications.
Numerous common fluid liquids such materials, such as polymers, pastes, creams, biological fluids (blood), paints, oil, food products, pharmacological cosmetics, building materials, oils, etc. not only have different requirements but also a very broad range of properties difficult to describe by a single theory, equation, or numerical value, and, thus require special methods of measurement and interpretation. Six chapters of this book outline these different needs of theory and practice, forming the foundations of rheology.
The book begins with fundamental aspects of continuum mechanics that define stresses and related deformations, describing fundamental principles, such as equations of conservation and applications of continuum mechanics in rheology.
The next (second) chapter discusses the commonly understood principles of flow and deformation of solids, such as those of Newtonian liquids and Hookean solids, respectively, followed by more complex phenomena of plasticity and linear viscoelasticity.
Non-linear effects in rheology are discussed in the third chapter. This chapter plays a central role in the book. It comprehensively describes various phenomena that seem “strange” to specialists brought up on classical continuum mechanics. These phenomena are inherent in many (if not all) real technological materials. These are unusual flow peculiarities of elastic liquids and yielding media, relaxation, and creep, the memory of past events, and damping in vibrations of elastic products. This chapter examines the fundamental role of structure that changes under external influence, as well as inevitable heterogeneities of real commercial materials and understanding of deformation-induced phase transitions. Finally, the issues discussed that are usually kept silent in books of this kind play a decisive role in today's life and science - these are bifurcations and the emergence of instability. turning into chaos
.
Chapters four and five concentrate on applying rheology to two main classes of liquids - polymeric and dispersed systems. They discuss the effects of molecular weight, concentration, temperature, and elasticity, as well as instabilities, viscoelasticity, uniaxial extension, stress, prokinetics, structural transitions, and many other aspects, as listed in the Table of Contents below. These chapters best represent what a researcher or consumer may encounter when dealing with real technical or household materials
The last chapter is devoted to measuring rheological properties with different types of viscometers, rheometers, plastometers, and penetrometers. It includes all available and most modern methods of measurement, their practical applications, and the interpretation of results. Both instruments for scientific research and standardized methods of technical testing are considered.
Some of the described striking rheological effects are illustrated by reproductions of paintings by great artists who convey the essence of the matter in their own language
Each chapter contains questions and answers to help readers check their mastery of the subject and further elaborate on discussed topics.
This book will provide every reader with a sufficient understanding of rheology to practice the subject with competence and it will be handy for consultation whenever required.
1. Introduction
1.1 What is rheology - the subject of rheology
1.2 Continuum mechanics - basic definitions
1.2.1 Stresses
1.2.2 Equations of conservation
1.2.3 Deformations
1.2.4 Kinematics of deformations
1.2.5 Continuum mechanics in rheology
1.3. Questions and problems
2. «Linear» media and materials
2.1 Linearity and Non-linearity
2.2 Newton viscous fluid
2.3 Hooke elastic solid
2.3.1 Introduction
2.3.2 Hookian natters (materials) (материалы)
2.3.3 Linear anisotropic elastic materials
2.3.4 Limits of elasticity
2.4 Plasticity
2.4.1 Plasticity as a phenomenon
2.4.2 Deformation hardening
2.4.3 Plasticity and fracture criteria
2.5 Linear viscoelasticity
2.5.1 Basic experiments - relaxation
2.5.2 Basic experiments – creep, delayed deformation
2.5.3 Basic experiments – fading memory
2.5.4 Basic experiments – harmonic oscillations
2.5.5 Deborah number and Weissenberg criterion
2.6 Questions and problems
3. Non-linear effects
3.1 Non-Newtonian viscosity
3.1.1 Basic definitions
.3.1.2 On the nature of non-Newtonian flow
3.1.3 Flow curves with the highest Newtonian viscosity
3.1.4 Flow curves of yielding liquids
3.2 Elasticity of liquids
3.2.1 Weissenberg effect – normal stresses in shear flow
3.2.2 Secondary flows
3.2.3 Non-linearity due to large elastic deformations
3.3 Nonlinear viscoelasticity
3.3.1 Nonlinear relaxation
3.3.2 Nonlinear creep
3.3.3 Periodic oscillations at large amplitudes
3.4 Structural and temporal effects
3.4.1 Thixotropy
3.4.2 Structure formation and durability
3.4.3 Phase transitions initiated by deformation
3.4.4 Heterogeneity in
3.4. Instabilities
3.5 Questions and problems
4. Rheological properties of polymers
4.1 Introduction
4.2 Rheology of polymer solutions
4.2.1 Diluted solutions
4.2.2 Concentrated solutions (viscosity)
4.2.3 Liquid crystal solutions of polymers
4.2.4 Non-Newtonian flow and elasticity of polymer solutions
4.2.5 Instability of the flow polymer solutions
4.2.6 Toms effectффект Томса
4.3 Rheology of melts of flexible-chain polymers
4.3.1 Viscosity of melts
4.3.2 Dependence of viscosity on molecular weight
4.2.Temperature dependence of viscosity
4.2.4 Viscoelasticity and elasticity of polymer melts
4.2.5 Uniaxtial extension of polymers
4.2.6 Rheokinetics – rheology in processes of synthesis and transformation of polymers
- 4.2.7 Instability of shear flow
4.4 On physical models in the polymer rheology
4.5. Questions and problems
5. Rheology of dispersed materials
5.1 Introduction
5.2 Diluted dispersions
5.3 Viscosity of semi-diluted and concentrated dispersions
5.4 Non-Newtonian effects in concentrated dispersions
5.4.1 Low-stress region - yield strength
5.4.2 High-stress region - deformation structuring
5.4.3 Electro- (magneto) rheological effects
5.4.4 Features of the rheological properties of various concentrated dispersions
5.5 Concentrated and super-concentrated emulsions
5.6 Instability and destruction of droplets in emulsions
5.6.1 Phase and structural transitions
5.6.2 Breakdown of droplets in emulsions
5.7 Questions and problems
6. Instrumental methods
6.1 Introduction – classification
6.2 Rotational rheometry
6.2.1 Rotational viscometry - Couette flow
6.2.2 Rotational rheometry based on Couette flow
6.2.3. Deformation between conical and flat surfaces
6.2.4 Rotary instruments
6.2.5 Industrial methods
6.2.6 Tasks and possibilities of rotational rheometry
6.3 Capillary viscometry
6.3.1 Measurement principles
6.3.2 Amendments
6.3.3 Capillary viscometers
6.3.4 Problems solved by methods of capillary viscometry
6.4 Viscometers. Plastometers, Penetrometers
6.4.1 Motion of a rigid body within a liquid medium
6.4.2 Plastomers
6.4.3 Telescopic shift method. Penetrometers
6.5 Measurement of extensional viscosity
` 6.5.1 Introduction
6.5.2 Methods
6.6. Measurement of viscoelastic properties by dynamic method (vibration methods)
6.6.1 Introduction
6.6.2 Torsional vibrations
6.6.3 Resonant vibrations
6.6.4 Damped (free) vibrations
6.6.5 Vibrational viscometry
6.6.7 Wave propagation
6.7. Physical methods
6.7.1 Rheo-optical methods
6.7.2 Velocimetry
6.7.3 Small-angle neutron scattering
6.7.4 Viscometer-calorimeters
6.8 Questions and problems
Prof. Dr. Alexander Ya. Malkin, Principal Research Fellow, Institute of Petrochemical Synthesis, Russian Academy of Sciences, Moscow, Russia
