Friction in Textile Materials

B S Gupta

• Publisher: Woodhead Publishing
• Year: 2008
• ISBN:
  9781845694722
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

Friction is a major issue in both the production of textiles and in the finished product. This authoritative book reviews how friction occurs and the ways it can be measured and controlled.The book begins by looking at how friction can be defined and how the structure and properties of textile fibres lead to friction behaviour. It also discusses slip-stick phenomena in textiles and ways of measuring friction in yarns and fabric. The second part of the book reviews friction in particular textiles, including cotton, wool and synthetic fibres as well as woven fabrics. These and other chapters also discuss ways of controlling friction, including fabric finishes and lubricants.With its distinguished editor and contributions from some of the world's leading authorities in the subject, Friction in textile materials is a standard reference for the textile industry and those researching this important topic.

• An authoritative review of friction, its management and control

1

Textile fiber morphology, structure and properties in relation to friction

BS GUPTA, North Carolina State University, USA

Publisher Summary

This chapter presents that friction is a surface phenomenon; however, it is governed by both the surface and the bulk properties of the material. It entails a comprehensive understanding of a material’s morphology and its chemical and physical structures and properties. Morphology, i.e., surface architecture, should influence the nature of contact between two bodies brought against each other. Chemical structure should affect the bonding between molecular layers within the body as well as the forces on the free surface that interact with other surfaces. The chapter discusses the information on structure and properties that may serve as useful background knowledge for fibers and textiles. A large number of fibers are used in making traditional textile and specialty technical products. They differ from each other in chemical and physical structures and, as a consequence, in their surface and bulk properties. The surface morphology and the surface and bulk physical properties, including mechanical, play important roles in influencing a fiber’s frictional properties and through it the latter’s performance in processing, handling, and end use. The details discussed in the chapter serve as useful background information for understanding the frictional behavior of fibers.

1.1 Introduction

Friction is a surface phenomenon; however, it is governed by both the surface and the bulk properties of the material. This entails a comprehensive understanding of a material’s morphology and its chemical and physical structures and properties. Morphology, i.e. surface architecture, should influence the nature of contact between two bodies brought against each other. Chemical structure should affect the bonding between molecular layers within the body as well as the forces on the free surface that interact with other surfaces. The physical structure combined with the chemical affect the bulk properties, especially the specific shear strength and the compressional modulus (hardness) of material, both of which are known to affect the frictional force.

Another structure-dependent bulk mechanical property, i.e. the viscoelastic behavior, affects the nature of the friction profile obtained as a function of time. Surface energetics, a function of morphology and chemical structure, play an important role in governing the tribological behavior of materials. For example, the application of any finish, such as a lubricant, to modify friction, requires that the chemical used is compatible with the surface. Compatibility between two materials is reflected by the contact angle, which in turn is a function of the magnitude and the nature of the surface energies of the substrate and the agent.

There are other properties, as well, that one should consider in fully understanding and controlling friction. Textiles are exposed to both dry and wet conditions during processing and use. Fibers vary in their interaction with moisture; those which are hydrophilic absorb aqueous fluids into their internal structure, swell and undergo a change in their frictional behavior. The greater the absorption, the greater is the change. Those that are hydrophobic will tend to accept oils and oil-based treatments on the surface more readily. Another property of interest is the response of fibers to heat. It is well known that frictional energy is converted into thermal, which can lead to significant rises in temperature. Fibers being particularly non-conducting, the changes can be enormous, as the temperature increase will tend to be localized. If a lubricant is present, its viscosity can change which will affect friction.

In this chapter, the information on structure and properties are provided that may serve as useful background knowledge for fibers and textiles whose frictional behaviors are discussed in the book.

1.2 Fiber classification

Numerous fibers exist that are used in producing textile products. They vary in chemical an...

Table of contents

• Cover image
• Title page
• Table of Contents
• The Textile Institute and Woodhead Publishing
• Copyright
• Dedication
• Contributor contact details
• Woodhead Publishing in Textiles
• Preface
• Introduction
• Chapter 1: Textile fiber morphology, structure and properties in relation to friction
• Chapter 2: Fundamental concepts of friction and lubrication affecting textile fibers
• Chapter 3: Friction behavior of fibrous materials used in textiles
• Chapter 4: Stick-slip phenomena in textiles
• Chapter 5: Experimental methods for analyzing friction in textiles
• Chapter 6: Friction and surface characteristics of cotton fibers
• Chapter 7: Friction, felting and shrink-proofing of wool
• Chapter 8: Friction and surface characteristics of synthetic fibers
• Chapter 9: The role of fiber friction in staple fiber processing
• Chapter 10: Friction in woven fabrics
• Chapter 11: Finishes and treatments to control friction in textile fibers
• Chapter 12: Boundary lubrication phenomena in coated textile surfaces
• Index