Lieng-Huang Lee - Böcker

Between June 6-10, 1988, the Third Chemical Congress of North America was held at the Toronto Convention Center. At this rare gathering, fifteen thousand scientists attended various symposia. In one of the symposia, Professor Pierre-Gilles de Gennes of College de France was honored as the 1988 recipient of the Amer ican Chemical Society Polymer Chemistry Award, sponsored by Mobil Chemical Corporation. For Professor de Gennes, this international setting could not be more fitting. For years, he has been a friend and a lecturer to the world scientific community. Thus, for this special occasion, his friends came to recount many of his achievements or report new research findings mostly derived from his theories or stimulated by his thoughts. In this volume of Proceedings, titled New Trends in Physics and Physical Chemistry of Polymers, we are glad to present the revised papers for the Symposium and some contributed after the Symposium. In addition, we intend to include most of the lively discussions that took plaGe during the conference. This volume contains a total of thirty-six papers divided into six parts, primarily according to the nature of the subject matter: • Adsorption of Colloids and Polymers. • Adhesion, Fractal and Wetting of Polymers. • Dynamics and Characterization of Polymer Solutions. • Diffusion and Interdiffusion of Polymers. • Entanglement and Reptation of Polymer Melts and Networks. • Phase Transitions and Gel Electrophoresis.

New technologies constantly generate new demands for exotic materials to be used in severe environments. The rapid developments of aerospace industries during the last two decades have required new materials to survive extreme high and low temperatures and various radiations. The exploration of new energy sources, e.g., solar and geothermal, has led us to develop new solar collectors and geothermal devices. Even the search for new oils has demanded that we study the corrosive environment of oil fields. In the telecommunication industries, optical fibers have been adopted broadly to replace metallic conductors. However, none of the optical fibers can survive abrasion or corrosion without the application of a coating material. For microelectronics, protection in terms of coatings and encapsulants is deemed necessary to prevent corrosion. One of the major causes of corrosion has been shown to be water which appears to be abundant in our earthly environments. Water can attack the bulk adhesive (or sealant), the interface, or the adherend. Water can also cause delamination of coating film, and it is definitely the major ingredient in causing cathodic or anodic corrosion. Thus, water becomes the major obstacle in solving durability problems of various materials in harsh environments.

Since the first symposium on Recent Advances in Adhesion, held September, 1971 in Washington, D. C. , this Division of the American Chemical Society has continuously sponsored several symposia on adhesion and adhesives. The chemists have gradually realized the importance of adhesion in various fields of science and technology. During these years, the science of adhesion has steadily grown along with progress in surface science and fracture mechanics. Moreover, new adhesives have been invented and applied in actual structures, for example, structural and aerospace adhesives. In response to socio-economic demands, new forms of adhesives have been introduced to combat the problems of pollution and to promote energy-conservation. The developments of hot-melt adhesives, waterborne adhesives, and radiation-curable adhesives are vivid examples of successes in solving some of the problems. As chemists, our hatural desire is to understand how those new adhesives and new forms of adhesives are made. Thus, we are interested in learning about the chemistry of adhesives so that we may create new generations of materials to satisfy future needs. It was based on this common interest that w~ set forth to org'anize this Symposium on Recent Developments in Adhesive Chemistry. It was held from March 21 through 23, 1983 in the Westin Hotel, Seattle, Washington. The Symposium was very well attended. As a matter of fact, for the first two sessions, we had to move from the smaller Mt. St.

Honolulu is a most beautiful place, suitable for all occa­ sions. Its choice as the meeting site for the first Joint Chemical Congress between the American Chemical Society and the Chemical Society of Japan was praised by scientists from both sides. During this Congress, the International Conference on Adhesion and Adsorption of Polymers was held at the Hyatt Regency Hotel between April 2 and 5, 1979. We had speakers from ten nations presenting over forty papers related to the subject matter. It was a memorable event. Unlike our two previous adhesion symposia held in 1971 and 1975, this was the first time in the same conference that we discussed both adhesion and adsorption of polymers simultaneously. These two important phenomena are not only inter-related, but also equally important in adhesive technology as well as biochemical processes. The papers presented to this Conference deal with these two phenomena from both fundamental and practical viewpoints. Furthermore, with the advance of new surface analytical techniques, the actual, microscopic happenings at the interfaces can be pin­ pointed. Thus, characterization of interface became one of the major focuses of this Conference. As a result, a broad coverage of the subject matter includes statistical thermodynamics, surface physics, surface analysis, fracture mechanics, viscoelasticity, failure analysis, surface modification, adsorption kinetics, bio­ polymer adsorption, etc. Thanks to the diligence of our contri­ butors, we are now able to publish the final papers in these two volumes.

The first ACS Adhesion Symposium was held in Washington, D.C., September 1971. During the four years since that meeting, much interest in adhesion has been generated among six divisions of the American Chemical Society. Then, in 1974, the Macromolecular Secretariat appointed me to work closely with the six Session chairmen in organizing this Symposium on Science and Technology of Adhesion. Needless to say, the success of the Symposium which took place between April 7 and 10, 1975 in Philadelphia, Pa., is due to their excellent cooperation and the enthusiastic response of con­ tributors. As originally planned, each division was responsible for one session, and most of the papers, including several late con­ tributions, are published in these two volumes of proceedings. During the Symposium, we held a banquet in honor of Professor Herman Mark in celebration of his eightieth birthday. His Plenary Lecture and the Symposium Address by Professor Murray Goodman are published in full at the beginning of the first volume. I thank Professors Mark and Goodman for their excellent presentations on this memorable occasion.

Polymers and polymer composites have been increasingly used in place of metals for various industries; namely, aerospace, automotive, bio-medical, computer, electronhotograohy, fiber, and rubber tire. Thus, an understanding of the interactions between polymers and between a polymer and a rigid counterface can enhance the anplications of polymers under various environments. In meet­ ing this need, polymer tribology has evolved to deal with friction, lubrication and wear of polymeric materials ann to anSwer some of the problems related to polymer-polymer interactions or nolymer­ rigid body interactions. The purpose of this first International Symposium was to introduce advances in studies of polymer friction and wear, especially in Britain and the U. S. S. R. Most earlier studies of the Fifties were stimulated by the growth of rubber tire industries. Continuous research through the Sixties has broadened the base to include other polymers such as nylon, polyolefins, and poly tetra­ fluoroethylene, or PTFE. However, much of this work was published in engineering or physics journals and rarely in chemistry journals: presumably, the latter have always considered the work to be too applied or too irrelevant.

Honolulu is a most beautiful place, suitable for all occa­ sions. Its choice as the meeting site for the first Joint Chemical Congress between the American Chemical SOCiety and the Chemical Society of Japan was praised by scientists from both sides. During this Congress, the International Conference on Adhesion and Adsorption of Polymers was held at the Hyatt Regency Hotel between April 2 and 5, 1979. We had speakers from ten nations presenting over forty papers related to the subject matter. It was a memorable event. Unlike our two previous adhesion symposia held in 1971 and 1975, this was the first time in the same conference that we discussed both adhesion and adsorption of polymers simultaneously. These two important phenomena are not only inter-related, but also equally important in adhesive technology as well as biochemical processes. The papers presented to this Conference deal with these two phenomena from both fundamental and practical viewpoints. Furthermore, with the advance of new surface analytical techniques, the actual, microscopic happenings at the interfaces can be pin­ pointed. Thus, characterization of interface became one of the major focuses of this Conference. As a result, a broad coverage of the subject matter includes statistical thermodynamics, surface physics, surface analysis, fracture mechaniCS, viscoelasticity, failure analysis, surface modification, adsorption kinetics, bio­ polymer adsorption, etc. Thanks to the diligence of our contri­ butors, we are now able to publish the final papers in these two volumes.

Polymers and polymer composites have been increasinqly used in place of metals for various industries; namely, aerospace, automotive, bio-medical, computer, electrophotography, fiber, and rubber tire. Thus, an understanding of the interactions between polymers and between a polymer and a rigid counterface can enhance the applications of polymers under various environments. In meet­ ing this need, polymer tribology has evolved to deal with friction, lubrication and wear of polymeric materials and to answer some of the problems related to polymer-polymer interactions or oolymer­ rigid body interactions. The purpose of this first International Symposium was to introduce advances in studies of polymer friction and wear, especially in Britain and the U.S.S.R. Most earlier studies of the Fifties were stimulated by the growth of rubber tire industries. Continuous research through the Sixties has broadened the base to include other polymers such as nylon, polyolefins, and poly tetra­ fluoroethylene, or PTFE. However, much of this work was published in engineering or physics journals and rarely in chemistry journals; presumably, the latter have always considered the work to be too applied or too irrelevant. Not until recent years have chemists started to discover words such as tribo-chemistry or mechano­ chemistry and gradually become aware of an indispensable role in this field of polymer tribology. Thus, we were hoping to bring the technology up to date during this SympOSium, especially to the majority of participants, polymer chemists by training.