Book contents
- Frontmatter
- Contents
- Preface
- Contributors
- Elastomeric Proteins
- 1 Functions of Elastomeric Proteins in Animals
- 2 Elastic Proteins: Biological Roles and Mechanical Properties
- 3 Elastin as a Self-Assembling Biomaterial
- 4 Ideal Protein Elasticity: The Elastin Models
- 5 Fibrillin: From Microfibril Assembly to Biomechanical Function
- 6 Spinning an Elastic Ribbon of Spider Silk
- 7 Sequences, Structures, and Properties of Spider Silks
- 8 The Nature of Some Spiders' Silks
- 9 Collagen: Hierarchical Structure and Viscoelastic Properties of Tendon
- 10 Collagens with Elastin- and Silk-like Domains
- 11 Conformational Compliance of Spectrins in Membrane Deformation, Morphogenesis, and Signalling
- 12 Giant Protein Titin: Structural and Functional Aspects
- 13 Structure and Function of Resilin
- 14 Gluten, the Elastomeric Protein of Wheat Seeds
- 15 Biological Liquid Crystal Elastomers
- 16 Restraining Cross-Links in Elastomeric Proteins
- 17 Comparative Structures and Properties of Elastic Proteins
- 18 Mechanical Applications of Elastomeric Proteins – A Biomimetic Approach
- 19 Biomimetics of Elastomeric Proteins in Medicine
- Index
4 - Ideal Protein Elasticity: The Elastin Models
Published online by Cambridge University Press: 13 August 2009
- Frontmatter
- Contents
- Preface
- Contributors
- Elastomeric Proteins
- 1 Functions of Elastomeric Proteins in Animals
- 2 Elastic Proteins: Biological Roles and Mechanical Properties
- 3 Elastin as a Self-Assembling Biomaterial
- 4 Ideal Protein Elasticity: The Elastin Models
- 5 Fibrillin: From Microfibril Assembly to Biomechanical Function
- 6 Spinning an Elastic Ribbon of Spider Silk
- 7 Sequences, Structures, and Properties of Spider Silks
- 8 The Nature of Some Spiders' Silks
- 9 Collagen: Hierarchical Structure and Viscoelastic Properties of Tendon
- 10 Collagens with Elastin- and Silk-like Domains
- 11 Conformational Compliance of Spectrins in Membrane Deformation, Morphogenesis, and Signalling
- 12 Giant Protein Titin: Structural and Functional Aspects
- 13 Structure and Function of Resilin
- 14 Gluten, the Elastomeric Protein of Wheat Seeds
- 15 Biological Liquid Crystal Elastomers
- 16 Restraining Cross-Links in Elastomeric Proteins
- 17 Comparative Structures and Properties of Elastic Proteins
- 18 Mechanical Applications of Elastomeric Proteins – A Biomimetic Approach
- 19 Biomimetics of Elastomeric Proteins in Medicine
- Index
Summary
INTRODUCTION
Definition of Ideal or Perfect Elasticity
Ideal elasticity is the property whereby the energy expended in deformation of the elastomer is completely recovered on removal of the deforming force. Because the energy expended in deformation is given by the area under the force, f, versus increase in length, ΔL, curve, a perfectly reversible force-extension curve means complete recovery on relaxation of the energy expended on deformation. Therefore, ideal elastomers exhibit perfectly reversible force-extension curves.
Perhaps our earliest perspective of the mechanism underlying ideal elasticity comes from a fundamental observation concerning rubber elasticity. In the mid-nineteenth century, Joule and Thomson noted a quantitative correlation between the increase in temperature of the elastomer due to stretching and the increase in force due to increasing the temperature (Flory, 1968). Thermodynamics provides for the analysis underlying this correlation, and the Boltzmann relation provides the bridge between experimental thermodynamic quantities and statistical mechanical description of molecular structures.
Continuing qualitatively with the Joule and Thomson correlation, heat produces motion, and the energy represented by heat distributes into the various available degrees of freedom in the chain molecules comprising the elastomer. Accordingly, the release of heat on stretching correlates with a loss of motion. By means of statistical mechanics, the loss of motion is seen as a decrease in entropy on extension. In addition, should solvent be essential for elasticity, this requires explicit consideration.
- Type
- Chapter
- Information
- Elastomeric ProteinsStructures, Biomechanical Properties, and Biological Roles, pp. 54 - 93Publisher: Cambridge University PressPrint publication year: 2003
- 4
- Cited by