Table Of Content
Introduction to Colloid
and Surface Chemistry
To Ann
Introduction to Colloid
and Surface Chemistry
Fourth Edition
Duncan J. Shaw, esc, Phd, FRSC
Formerly Principal Lecturer in Physical Chemistry,
Department of Chemistry and Biochemistry,
Liverpool Polytechnic
U T T E R W O R TH
E I N E M A N N
OXFORD AMSTERDAM BOSTON LONDON NEW YORK PARIS
SAN DIEGO SAN FRANCISCO SINGAPORE SYDNEY TOKYO
Butterworth-Heinemann
An imprint of Elsevier Science
Linacre House, Jordan Hill, Oxford OX2 8DP
200 Wheeler Road, Burlington, MA 01803
First published 1966
Reprinted 1968
Second edition 1970
Reprinted 1975, 1976, 1978, 1979
Third edition 1980
Reprinted 1983, 1985, 1986, 1989
Fourth edition 1992
Reprinted 1992, 1993, 1994 (twice), 1996, 1997, 1998, 1999, 2000
Transferred to digital printing 2003
Copyright © 1992, Elsevier Science Ltd. All rights reserved
No part of this publication may be reproduced in any material form (includ-
ing photocopying or storing in any medium by electronic means and whether
or not transiently or incidentally to some other use of this publication)
without the written permission of the copyright holder except in accordance
with the provisions of the Copyright, Designs and Patents Act 1988 or under
the terms of a licence issued by the Copyright Licensing Agency Ltd, 90
Tottenham Court Road, London, England WIT 4LP. Applications for the
copyright holder's written permission to reproduce any part of this publica-
tion should be addressed to the publisher
British Library Cataloguing in Publication Data
A catalogue record for this book is available from the British Library
Library of Congress Cataloguing in Publication Data
A catalogue record for this book is available from the Library of
Congress
ISBN 07506 11820
For information on all Butterworth-Heinemann Publications
visit our website at www.bh.com
Printed and bound in Great Britain by Antony Rowe Ltd, Eastbourne
Contents
Preface vii
1. The colloidal state 1
Introduction 1
Classification of colloidal systems 3
Structural characteristics 6
Preparation and purification of colloidal systems 10
2. Kinetic properties 21
The motion of particles in liquid media 21
Brownian motion and translational diffusion 23
The ultracentrifuge 31
Osmotic pressure 37
Rotary Brownian motion 44
3. Optical properties 46
Optical and electron microscopy 46
Light scattering 53
4. Liquid-gas and liquid-liquid interfaces 64
Surface and interfacial tensions 64
Adsorption and orientation at interfaces 76
Association colloids-micelle formation 84
Spreading 93
Monomolecular films 96
5. The solid-gas interface 115
Adsorption of gases and vapours on solids 115
Composition and structure of solid surfaces 136
vi Contents
6. The solid-liquid interface 151
Contact angles and wetting 151
Ore flotation 161
Detergency 163
Adsorption from solution 169
7. Charged interfaces 174
The electric double layer 174
Electrokinetic phenomena 189
Electrokinetic theory 199
8. Colloid stability 210
Lyophobic sols 210
Systems containing lyophilic material 234
Stability control 241
9. Rheology 244
Introduction 244
Viscosity 245
Non-Newtonian flow 252
Viscoelasticity 256
10. Emulsions and foams 262
Oil-in-water and water-in-oil emulsions 262
Foams 270
Problems 277
Answers 287
References 290
Index 298
Preface
This book has been written to fill a gap in the literature by offering a
standard and overall coverage of colloid and surface chemistry
intermediate between the brief accounts found in most textbooks of
physical chemistry and the comprehensive accounts found in special-
ised treatises on colloid and/or surface chemistry.
In writing the book, I have kept a number of audiences in mind -
particularly: university and polytechnic students studying for an
honours degree or its equivalent, or commencing a programme of
postgraduate research; scientists in industry who desire a broad
background in a subject which may have been somewhat neglected
during academic training; and those interested in branches of natural
science, for whom an understanding of colloid and surface phenomena
is essential.
The subject matter is, in general, approached from a fundamental
angle, and the reader is assumed to possess a knowledge of the basic
principles of physical chemistry. Opportunities have also been taken
to describe many of the practical applications of this subject. In
addition, some numerical problems (with answers) and a list of
references for further reading (mainly books and review articles) are
given at the end of the book.
The general character of this fourth edition is similar to that of the
third edition. The text has been revised and updated throughout, the
major change being the extension of Chapter 5 to include a section on
the composition and structure of solid surfaces.
I wish to thank my colleagues, particularly Dr A.L. Smith, for their
many helpful suggestions, and my wife, Ann, for her help in
preparing the manuscript and checking the text.
DJ.S.
Southport, 1991
This page intentionally left blank
1 The colloidal state
Introduction
Colloid science concerns systems in which one or more of the
components has at least one dimension within the nanometre (10-9m)
to micrometre (lO-"m) range, i.e. it concerns, in the main, systems
containing large molecules and/or small particles. The adjective
'microheterogeneous' provides an appropriate description of most
colloidal systems. There is, however, no sharp distinction between
colloidal and non-colloidal systems.
The range of colloidal systems of practical importance is vast, as is
the range of processes where colloidsurface chemical phenomena are
involved.
Examples of systems which are colloidal (at least in some respects)
are:
Aerosols Foodstuffs
Agrochemicals Ink
Cement Paint
Cosmetics Paper
Dyestuffs Pharmaceuticals
Emulsions Plastics
Fabrics Rubber
Foams Soil
Examples of processes which rely heavily on the application of
colloid/surface phenomena are:
Adhesion Ore flotation
Chromatography Precipitation
Detergency Road surfacing
