Structured Fluids: Polymers, Colloids, Surfactants

231 Pages·2010·3.55 MB·English

by  Thomas A. Witten, Philip A. Pincus

STRUCTURED FLUIDS
This page intentionally left blank
Structured Fluids
Polymers, Colloids, Surfactants
T. WITTEN
The University of Chicago,
Chicago, Illinois, USA
with
P. PINCUS
University of California,
Santa Barbara, USA
1
3
Great Clarendon Street, Oxford OX2 6DP
Oxford University Press is a department of the University of Oxford.
It furthers the University’s objective of excellence in research, scholarship,
and education by publishing worldwide in
Oxford NewYork
Auckland CapeTown Dar es Salaam HongKong Karachi
Kuala Lumpur Madrid Melbourne MexicoCity Nairobi NewDelhi
Shanghai Taipei Toronto
With offices in
Argentina Austria Brazil Chile CzechRepublic France Greece
Guatemala Hungary Italy Japan Poland Portugal
Singapore SouthKorea Switzerland Thailand Turkey Ukraine Vietnam
Oxford is a registered trade mark of Oxford University Press
in the UK and in certain other countries
Published in the United States
by Oxford University Press Inc., New York
© Oxford University Press, 2004
The moral rights of the author have been asserted
Database right Oxford University Press (maker)
First published 2004
First published in paperback 2010
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted, in any form or by any means,
without the prior permission in writing of Oxford University Press,
or as expressly permitted by law, or under terms agreed with the appropriate
reprographics rights organization. Enquiries concerning reproduction
outside the scope of the above should be sent to the Rights Department,
Oxford University Press, at the address above
You must not circulate this book in any other binding or cover
and you must impose this same condition on any acquirer
British library catalogue in Publication Data
Data available
Library of Congress Cataloging-in-Publication Data
Data available
Typeset by Newgen Imaging Systems (P) Ltd., Chennai, India
Printed in Great Britain
on acid-free paper by
The Bath Press, Avon
ISBN 978-0-19-958382-9
10 9 8 7 6 5 4 3 2 1
For Molly
This page intentionally left blank
Preface
This book is about fluids containing polyatomic structures such as polymer
molecules or colloidal grains. Such structured fluids have come to be known
as soft condensed matter. The book takes a scaling approach, following
de Gennes’s important monograph Scaling Concepts in Polymer Physics. My
purpose is to provide a unified, pedagogical introduction to soft-matter phenom-
ena that embodies this scaling approach. The book focuses on how to account
in the simplest way for the distinctive length, time, and energy scales that char-
acterize each phenomenon. This approach allows unity and simplicity, but it
provides only an initial glimpse into the rich phenomena and science to be found
in soft condensed matter. Notably, I omit an important aspect of soft matter: the
broken symmetry of the liquid crystalline state and the distinctive responses
and structures that arise from it. This realm of soft matter has benefited greatly
from the modern tools of differential geometry and field theory, as discussed
elegantly in the advanced text Principles of Condensed Matter Physics by Paul
Chaikin and Tom Lubensky (Cambridge, 1995).
The book began life in the late eighties as a joint venture with Phil Pincus
of the University of California, Santa Barbara. The chapters developed over
several cycles of teaching a course on structured fluids at Chicago. The intended
audience is the advanced undergraduate in physical science or engineering
who is comfortable with elementary physics and has seen elementary statistical
mechanics. The needed knowledge of physics is at the level of e.g., D. Halliday
and R. Resnick’s Fundamentals of Physics (New York, Wiley 2000). I assume
the student has seen statistical physics at the level of Reif’s book, the second
item of the list below. A working knowledge of Fourier transformation will also
be helpful.
Important conceptual points are illustrated by problems interspersed through
the text. The serious student should work these problems since the logical
development remains incomplete without them. Almost all of the problems
have been assigned, graded, and refined at least once. The book also includes
a number of suggested experimental projects using household materials. These
are intended to show concretely the principles discussed. They also give the
student a sense of how well the idealizations treated in the book apply to real
liquids. Students in the structured fluids course were required to do one of these
projects or some other project of their own devising. The projects are meant to
open a line of inquiry; only some have been tested, and the student may well find
that great modifications are needed to make them work. To guide the student to
further information, the book includes references to more detailed work. I have
tried to suggest sources in each major subject area. In some cases I have cited
primary journal articles, but these references are far from being thorough or
balanced. Corrections and additions to the text will be available via the Oxford
University Press web site, http://www.oup.com/.
viii Preface
In teaching the course, I found that the text contains too much material to be
covered in a one-quarter term with 27 class hours. It could probably be covered
rapidly in a one-semester course.
In learning from this book, there are several useful reference works to keep
in mind. The first and most important is de Gennes’s monograph on polymer
physics, Item 1 on the list below. Polymers serve as the paradigmatic system in
the book. Most of the ideas have been developed using polymers as an example,
then applied to other structured fluids. For further depth or clarification of these
ideas, de Gennes’s book is the best single source of which we are aware. The
subject depends heavily on ideas of statistical physics. The book develops all the
needed ideas within the text and aims to keep their number to a minimum. Still,
more explanation or depth on statistical physics may be helpful; a good source
is Reif’s book cited in Item 2. For the discussion of colloids and surfactants,
Item 3 is useful. This practical book by Jacob Israelachvili is about liquids
generally but contains much information about colloids and surfactants. For
collective properties of surfactant assemblies, Sam Safran’s book (Item 4) is
useful.
1. P.-G. de Gennes, Scaling Concepts in Polymer Physics (Ithaca NY: Cornell,
1979).
2. F. Reif, Fundamentals of Statistical and Thermal Physics (New York:
McGraw-Hill, 1965).
3. Jacob N. Israelachvili, Intermolecular and Surface Forces, 2nd ed. (London:
San Diego, CA: Academic Press, 1991)
4. Samuel A. Safran, Statistical Thermodynamics of Surfaces, Interfaces, and
Membranes (Reading, MA: Addison-Wesley Publication, 1994).
The reader should know about other classic and recent works that cover
the same material. The polymer physics material in Chapters 3 and 4 is
well covered by other textbooks and monographs. Two of the best known
are Paul J. Flory’s Statistical Mechanics of Chain Molecules (New York,
Interscience Publishers, 1969) and Charles Tanford’s Physical Chemistry of
Macromolecules (New York, Wiley 1961). There is also an important property
handbook: Polymer Handbook, 4th edition, by J. Brandrup, E. H. Immer-
gut and E. A. Grulke (New York, Wiley, 1999). An important monograph
written from a statistical physicist’s point of view is Polymers in Solution by
G. Jannink and J. Des Cloizeaux (Oxford, Clarendon Press, 1992). Another
monograph gives an authoritative treatment of polymer motions. It is The
Theory of Polymer Dynamics by Masao Doi and S. F. Edwards (New York,
Oxford University Press, 1986). Two recent textbooks offer a pedagogical
treatment of polymers: Statistical physics of Macromolecules by A. Yu. Gross-
berg and A. R. Khokhlov (New York, AIP Press, 1994), and Polymer Physics
by M. Rubinstein, R. H. Colby (New York, Oxford University Press, 2003).
A recent text covering a variety of structured fluids is Ronald G. Larson’s The
Structure and Rheology of Complex Fluids (New York, Oxford University Press,
1999). It is more advanced and more comprehensive than this book. Richard
A. L. Jones’s new text Soft Condensed Matter (Oxford, 2002), is similar to the
present book in scope and level.
Preface ix
By now the efforts of several people have improved the text greatly. The
book owes much to the generations of students who took the course, read early
drafts, and forced me to be more clear. Arlette Baljon, Alfred Liu, Keith Brad-
ley, Joe Plewa, and other students weeded out errors and confusing statements
in the text. Jung-ren Huang improved every chapter by his close reading and
thoughtful suggestions. He also compiled the data for the big table of semi-
dilute universal ratios in that chapter. Olgica Bakajin did the simulation to
make the dilation symmetry figure in the appendix of Chapter 3. Sidney Nagel
and other colleagues at the James Franck Institute took a lively interest in the
course, and the book benefited from their discussions and support. Oxford
editor Bob Rodgers provided early encouragement and obtained several very
useful reviews of an early draft of the book. Seven other reviewers looked at
the completed book last year and many improvements were made in response
to their wise suggestions. Phil Pincus inspired this entire project and wrote the
first draft of Chapter 5. He also spent many hours over several collaborative
visits to bring the book along. The book would not exist without the support
and encouragement of my wife Molly.
Chicago T. A. Witten
May 2003