Microstructure and Microtribology of Polymer Surfaces

525 Pages·2000·64.448 MB·English

by  Vladimir V. Tsukruk and Kathryn J. Wahl (Eds.)

Microstructure and Microtribology
1
0
0 of Polymer Surfaces
w
1.f
4
7
0
0-
0
0
2
k-
b
1/
2
0
1
0.
1
oi:
d
9 |
9
9
1
0,
1
er
b
m
e
c
e
D
e:
at
D
n
o
ati
c
bli
u
P

In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
About the Cover
An elegant micro-flower of 8 |nm across represents a fascinating
example of directional distribution of friction forces at the microscale
within a multidomain Langmuir film formed by chiral phospholipids.
1 This image is cordially provided by researchers from the Swiss
0
0
w Federal Institute of Technology (for details, see Chapter 7 in this vol
1.f
4 ume and the article in Science 1998,250, 273).
7
0
0-
0
0
2
k-
b
1/
2
0
1
0.
1
oi:
d
9 |
9
9
1
0,
1
er
b
m
e
c
e
D
e:
at
D
n
o
ati
c
bli
u
P

In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
ACS SYMPOSIUM SERIES 741
Microstructure and
Microtribology of Polymer
Surfaces
1
0
0
w
1.f
4
7
0
0-
0
0
2
k-
b
1/
2
0
1
0.
1 Vladimir V. Tsukruk, EDITOR
oi:
9 | d Iowa State University
9
9
1
0,
1
er Kathryn J. Wahl, EDITOR
b
m
e Naval Research Laboratory
c
e
D
e:
at
D
n
o
ati
c
bli
u
P

American Chemical Society. Washington, DC
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
QD 381.9 .S97M53 2000 c.l
Microstructure and
microtribology of polymer
Library of Congress
Microstructure and microtribology of polymer surfaces / Vladimir V. Tsukruk, editor, Kathryn J. Wahl,
editor.
p. cm. — (ACS symposium series, ISSN 0097-6156 : 741)
Includes bibliographical references and indexes.
ISBN 0-8412-3682-8
1
00 1. Polymers—Surfaces Congresses. 2. Contact mechanics—Congresses. 3. Tribology Congresses.
w
1.f
4
7 I. Tsukruk, V. V. (Vladimir Vasil'evich) II. Wahl, Kathryn J., 1964- . III. Series.
0
0-
0
0 QD381.9.S97M53 1999 99-16494
2
k- 547.7'0453—dc21 CIP
b
1/
2
0
1 The paper used in this publication meets the minimum requirements of American National Standard
0.
1 for Information Sciences—Permanence of Paper for Printer Library Materials, ANSI Z39.48-94 1984.
oi:
d
9 | Copyright © 2000 American Chemical Society
9
9
1
0,
1 Distributed by Oxford University Press
er
b
m All Rights Reserved. Reprographic copying beyond that permitted by Sections 107 or 108 of the U.S.
e
ec Copyright Act is allowed for internal use only, provided that a per-chapter fee of $20.00 plus $0.50 per
D
e: page is paid to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA.
at Republication or reproduction for sale of pages in this book is permitted only under license from ACS.
D
n Direct these and other permissions requests to ACS Copyright Office, Publications Division, 1155 16th
atio Street, N.W., Washington, DC 20036.
c
bli The citation of trade names and/or names of manufacturers in this publication is not to be construed as
u
P an endorsement or as approval by ACS of the commercial products or services referenced herein; nor
should the mere reference herein to any drawing, specification, chemical process, or other data be
regarded as a license or as a conveyance of any right or permission to the holder, reader, or any other
person or corporation, to manufacture, reproduce, use, or sell any patented invention or copyrighted
work that may in any way be related thereto. Registered names, trademarks, etc., used in this
publication, even without specific indication thereof, are not to be considered unprotected by law.
PRINTED IN THE UNITED STATES OF AMERICA
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
Advisory Board
ACS Symposium Series
Mary E. Castellion Omkaram Nalamasu
ChemEdit Company AT&T Bell Laboratories
Arthur B. Ellis Kinam Park
University of Wisconsin at Madison Purdue University
1 Jeffrey S. Gaffney Katherine R. Porter
0
w0 Argonne National Laboratory Duke University
1.f
4 Gunda I. Georg
7 Douglas A. Smith
0
00- University of Kansas The DAS Group, Inc.
0
2
bk- Lawrence P. Klemann Martin R. Tant
1/ Nabisco Foods Group
2 Eastman Chemical Co.
0
1
0. Richard N. Loeppky
doi: 1 University of Missouri PMarikceh-aDealv iDs .P hTaarmylaoceru tical
99 | Cynthia A. Maryanoff Research
9
10, 1 R. RWe.s eJaorhcnhso Inn sPtithuatrem aceutical Leroy B. Townsend
er University of Michigan
b
m Roger A. Minear
e
c William C. Walker
e University of Illinois
D
e: at Urbana-Champaign DuPont Company
at
D
n
o
ati
c
bli
u
P

In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
Foreword
1HE ACS SYMPOSIUM SERIES was first published in 1974 to provide
a mechanism for publishing symposia quickly in book form. The pur
pose of the series is to publish timely, comprehensive books devel
oped from ACS sponsored symposia based on current scientific re
search. Occasionally, books are developed from symposia sponsored
by other organizations when the topic is of keen interest to the chem
istry audience.
1 Before agreeing to publish a book, the proposed table of contents
0
w0 is reviewed for appropriate and comprehensive coverage and for in
1.f terest to the audience. Some papers may be excluded in order to better
4
7
0 focus the book; others may be added to provide comprehensiveness.
0-
0 When appropriate, overview or introductory chapters are added.
0
2
k- Drafts of chapters are peer-reviewed prior to final acceptance or re
b
1/ jection, and manuscripts are prepared in camera-ready format.
2
0
1 As a rule, only original research papers and original review pa
0.
oi: 1 pers are included in the volumes. Verbatim reproductions of previ
d ously published papers are not accepted.
9 |
9
9
1
0, ACS BOOKS DEPARTMENT
1
er
b
m
e
c
e
D
e:
at
D
n
o
ati
c
bli
u
P

In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
Preface
This book is a first collection of chapters dealing with tribological studies of polymeric
materials, both on a macroscopic scale and at the microscopic scale. Although friction and
wear of polymers and polymer composites have been widely studied on a macroscopic
scale for many decades, the complexities of these surfaces provide challenging problems
for scientists to understand and for tribologists to overcome. The advent of new analytical
techniques during the past two decades has allowed investigation of polymer tribology
and materials properties on a microscopic scale. This has resulted in not only
improvements in both spatial and depth resolution but also has contributed to new insights
and observations of fundamental properties of polymer surfaces. However, the rapid
development of experimental techniques to probe these surfaces is at times faster than the
ability to adequately model and interpret the results. For example, we are still struggling
1
00 with ways to distinguish between and to model different types of energy dissipation
1.pr observed in the dynamic experiments for viscoelastic materials. Time- and temperature-
4
7 dependent measurements of surface properties at the microscale are now possible, but the
0
0- parameters required for measurements remain difficult to control. We believe that we are
0
0
2 only beginning to learn about the properties of polymer surfaces at the microscale.
k-
1/b The contributions in this book were presented at an international symposium
02 organized at the American Chemical Society National Meeting in Boston, Massachusetts,
1
0. August 1998. A total of 62 presentations were delivered by participants from 15
1
oi: countries. A majority of the oral presentations were invited lectures reviewing selected
d
9 | subjects and original contributions were presented at the poster session. The major focus
99 of this symposium was on the relationship between microstructural, micromechanical, and
1
0, tribological properties of polymeric materials, and on bridging the gap between
1
er microstructural and macroscopic surface properties. Symposium topics encompassed a
b
m variety of experimental and theoretical investigations of micromechanical and tribological
e
ec properties of polymeric materials: polymers, composites, coatings, ultrathin films, and
D
e: molecular layers. Industrial applications of polymeric materials were considered in a
Dat separate session as well.
on Leading researchers, who presented papers at this symposium, were invited to
ati contribute original articles and reviews to this volume. The 30 chapters collected here
c
bli address a range of problems from treatment of contact mechanics for compliant,
u
P
viscoelastic materials to relationships between polymer microstructure and surface
properties. Although no single book can encompass all of the current research and
scientific issues in this topic area, we hope that this book will provide an overview of the
present state of knowledge of polymer surface tribology, microstructure, and mechanics.
A general introductory chapter written by B. J. Briscoe from Imperial College gives a
brief overview of the current status of the field of polymer tribology. The rest of the book
is divided into four topic areas.
Contact Mechanics of Polymeric Materials
Tribological properties of polymers are strongly influenced by adhesion and elastic, and
viscoelastic properties as well as by surface forces. K. L. Johnson reviews progress in
xi
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
extending the JKR theory to viscoelastic spheres, enabling prediction of adhesion
hysteresis and rate-dependent adhesion observed experimentally. J. C. Charmet et al.
review how the mechanical behavior of contacting solids is influenced by both surface
adhesion and bulk viscoelastic properties of rubberlike material. They explain spontaneous
peeling, rolling contact, and Shallamach waves as well as the rebound behavior (or lack
of!) for balls bounced against soft elastomers. Creep effects in viscoelastic polymers are
discussed by W. N. Unertl, who concludes that creep effects may dominate over crack-tip
effects for nanoscale contacts to low moduli materials. K. Vorvolakos and M. K.
Chaudhury's studies (utilizing fluorescent particle velocimetry to observe slippage at
surfaces) describe how release of adhesive contacts is governed by interfacial friction. M.
O. Robbins and A. R. C. Baljon compare experiments and simulations of thin films
undergoing oscillatory shear and discuss the effects of confinement on behavior including
glass transitions, stick-slip phenomena, and memory effects in thin films.
1
0
pr0 Micromechanics and Microtribology
1.
4
7
0
0- This section introduces a variety of proximal probe techniques to study response of
0
20 polymer surfaces and thin films. A variety of techniques have been implemented (both dc
bk- and ac) to examine adhesion, friction, wear, and micromechanics of polymers; both time-
1/
2 and temperature-dependent effects are examined. F. Oulevey et al. describe changes in
0
0.1 mechanical properties of polymer blends in response to temperature changes, as well as
1
oi: friction anisotropics and asymmetries in Langmuir-Blodgett films that they ascribe to
d molecular tilt. S. Kopp-Marsaudon et al. describe and compare the mechanical response
99 | of polymer films to different atomic force microscope (AFM) techniques employing both
9
0, 1 contact and intermittent contact operational modes. R. M. Overney et al. discuss friction
er 1 effects, mechanical properties and dewetting of ultrathin, spin-cast polymer films, and
b relate these responses to flow, disentanglement, and surface strain. Z. Huang et al.
m
ce describe experiments using cantilever beam-bending techniques with an AFM to compare
e
D surface micromechanical properties from a variety of compliant and glassy polymers. G.
e:
at Meyers et al. use AFM and nanoindentation to study adhesion and mechanical properties
D
n of polymer surfaces. O. Marti and S. Hild used AFM techniques to investigate adhesion
o
ati and stiffness of polystyrene filmsa s a function of temperature and molecular weight. R. H.
c
bli Schmidt et al. describe the flow response of polystyrene to raster scanning with an AFM
u
P tip at various temperatures and relate the patterns formed at different scanning rates and

temperatures using the time-temperature superposition principle. C. Basire and C.
Fretigny present work on sliding transitions and mechanical properties of viscoelastic
contacts using AFM. G. S. Blackman et al. use a combination of AFM and a micro-
scratch tester to study wear modes of polymer materials at both micro- and nanoscales.
Surface Microstructures of Various Polymers
This section contains chapters that deal with chemical and microstructural properties of
polymer surfaces. K. Feldman et al. examine the influence of chemistry (e.g., pH, polarity,
or termination) and mechanics on the behavior of nanoscale contacts for various
polymers. Hammerschmidt et al. present work on temperature-dependent behavior of
xii
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
nanoscale frictional contacts to polymers and attribute the responses to relaxation and
viscoelastic losses. B. Nysten et al. describe AFM-based experiments investigating
mechanics of copolymer surfaces. G. J. Vancso and H. Schdnherr describe nanoscale
friction anisotropics found on polymer single crystals and highly oriented polymer fibers.
T. Fujii et al. examine surface morphology and frictional anisotropy of high-density
polyethylene single crystals as a function of molecular weight. S. Sheiko et al. investigate
morphology of monolayer films of polymer brushes and actual shape of isolated cylindrical
macromolecules at surface. Ph. Leclere et al. examine transitions in surface morphology of
triblock copolymers as a function of composition and molecular weight. A. Balazs et al.
model polymer-clay interactions to predict conditions under which the polymer will
exfoliate the layers within the clay particles.
Testing Polymer Applications
1
0
0
pr Polymers are widely used in applications throughout industry. This section presents a
1.
4 sampling of the various ways in which polymers are used in practical applications, and
7
0
0- methods that researchers use to characterize performance of these materials. K. Budinski
0
0 reviews the basic wear tests for plastics and the criteria for selecting an appropriate test
2
bk- methodology for various applications. C. M. Mate and J. Wu describe a new polymer
21/ lubricant layer to protect hard disk surfaces as well as discuss the use of contact angle
0
0.1 measurements to evaluate lubricant behavior on surfaces. N, S. Eiss and E. Lee examine
oi: 1 surface texture effects on plastics used in automobile interiors in an effort to reduce stick-
d slip occurrences (observed by vehicle occupants as noise). L. Lin et al. describe micro-
99 | scratch tests of automobile topcoats (protecting basecoat paint) to quantitatively
9
1 characterize the scratch and mar behavior and to determine damage mechanisms. W. Shen
0,
1 and F. N. Jones also examine mar resistance, damage mechanisms, and healing behavior of
ber coatings using AFM. M. T. Dugger et al. use AFM and specially fabricated
m
e microelectromechanical systems (MEMS) device to examine frictional behavior of
c
e
D nanoscale lubricated contacts. Finally, A. Liebmann-Vinson examines the tribological
ate: performance of syringes and methods used to control and measure frictional behavior of
D
n these biomedical devices.
o
ati
c
bli A cknowledgments
u
P

We hope that readers of this volume will enjoy the images depicted on the cover. An
elegant "micro-flower" of about 8 ^im across represents a fascinating example of
directional distribution of friction forces at the microscale within a multidomain Langmuir
film formed by chiral phospholipids. This image is cordially provided by researchers from
Swiss Federal Institute of Technology (for details, see the chapter in this volume and the
article in Science, 1998, 280, 273). Complimentary cover image shows an AFM cantilever
in a torsional deformational mode (a bit exaggerated though) used to collect friction force
microscopic data frequently discussed in this volume and images similar to that presented
on the cover. The finite element analysis model displayed here was built by J. Hazel,
Western Michigan University (for details, see the article in Thin Solid Films, 1999, 339,
249).
xiii
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.
We are grateful for all the hard and time-consuming work that the symposium
lecturers and poster contributors devoted to this meeting. Also, we are espeically
appreciative of the efforts of the many authors who provided written chapters comprising
this volume, and of the reviewers for their comments. The willing participation of
researchers from a broad cross-section of science and engineering disciplines, especially
those from the more "macroscopic" perspective, was essential to the success of such a
meeting, and provided the necessary framework upon which discussions were built.
Finally, we acknowledge the sponsors who supported the symposium, which
became a basis for this volume: the American Chemical Society Division of Polymer
Chemistry, Inc., The Surface Engineering and Tribology Program of The National Science
Foundation, the Air Force Office of Scientific Research, and The Petroleum Research
Fund. We also are especially grateful to all the students who worked very hard to ensure
the smooth running of the symposium: John Hazel, Kirsten Larson, Zheng Huang, and
Melbs Lemieux.
1
0
0
pr
41. VLADIMIR V. TSUKRUK
7
0 Department of Materials Science and Engineering
0-
0 Iowa State University
0
2
k- Ames, IA 50011
b
1/
2
10 KATHRYN J. WAHL
10. Tribology Section, Code 6176
oi: Naval Research Laboratory
d
9 | Washington, DC 20375-5342
9
9
1
0,
1
er
b
m
e
c
e
D
e:
at
D
n
o
ati
c
bli
u
P

xiv
In Microstructure and Microtribology of Polymer Surfaces; Tsukruk, V., et al.;
ACS Symposium Series; American Chemical Society: Washington, DC, 1999.