This book constitutes the Proceedings of the NATO Advanced Research Workshop on Conjugated Polymers held at the University of Mons, Belgium, during the first week of September 1989. The Workshop was attended by about fifty scientists representing most of the leading research groups within NATO countries, that have contributed to the development of conjugated polymeric materials. The program was focused on applications related to electrical conductivity and nonlinear optics. The attendance was well balanced with a blend of researchers from academic, industrial, and government labs, and including synthetic chemists, physical chemists, physicists, materials scientists, and theoreticians. The Workshop provided an especially timely opportunity to discuss the important progress that has taken place in the field of Conjugated Polymers in the late eighties as well as the enormous potential that lies in front of us. Among the recent significant developments in the field, we can cite for instance: (i) The discovery of novel synthetic routes affording conjugated polymers -that are much better characterized, especially through control of the molecular weight; - that can be processed from solution or the melt; the early promise that conducting polymcrs would constitute materials combining the electrical conductivities of metals with the mechanical properties of plastics is now being realized; -that can reach remarkably high conductivities.

CONJUGATED POLYMERS: THE IMTERPLAY BETWEEN SYNTHESIS, 1 STRUCTURE, AND PROPERTIES C. B. GORMAN and R. H. GRUBBS 1. Introduction 2 2. Structural Features of Conjuqated. Polyaers 3 3. Polymer Synthesis: Basic Methods 4 3. 1 Step-Growth Polymerization 5 3. 2 Chain-Growth Polymerization 6 3. 3 Rinq-Openinq Polymerization 8 4. Direct Synthetic Methods 8 4. 1 Electrochemical Synthesis 9 4. 2 Synthesis by Step-Growth Polymerization 11 4. 2. 1 Polyaniline (PAN) 11 4. 2. 2 Poly(Phenylene Sulfide) 12 4. 2. 3 Poly thiophene and its Derivatives 13 4. 2. 4 Other 5-membered Heterocyclic 16 Derivatives 4. 2. 5 Polyparaphenylene (PPP) 17 4. 2. 6 Polysilanes 18 4. 2. 7 Polymers of Phthalocyanines 19 4. 2. 8 Other Conjugated Metal Coordination 20 Polymers 4. 2. 9 Ladder Polymers 21 4. 3 The Unusual Topochemical Polymerization to 23 form Polydiacetylenes 4. 4 Chain-Growth Polymerizations 24 4. 4. 1 Polyacetylene via Ziegler-Natta 24 Polymerization 4. 4. 2 Ring-Opening Metathesis Polymerization 26 Routes to Polyacetylenes 5. Polymers fro. precursors 27 5. 1 Polyparaphenylene (PPP) 27 5. 2 Poly(Phenylene Vinylene) (PPV) and Other 28 Vinylene Polymers 5. 3 Precursors to Polyacetylene 29 6. Extentions of these Methods in the Synthesis of 31 *saall-Bandqap* Pplymers 7. Conjuqated. Polymer Matrices 33 8. Conclusions and Caveats 35 Acknowled. qements 36 References 36 vi TABLE OF CONTENTS PROPERTIES OF HIGHLY CONDUCTIHG POLYACETYLEHE 49 Th. SCHIMMEL, D. GLASER, M. SCHWOERER AND H. NAARMANN 1. Introduction 50 2. SBIlpie Synthesis, lIorphology and Properties 52 2.

This book constitutes the Proceedings of the NATO Advanced Research Workshop on Conjugated Polymers held at the University of Mons, Belgium, during the first week of September 1989. The Workshop was attended by about fifty scientists representing most of the leading research groups within NATO countries, that have contributed to the development of conjugated polymeric materials. The program was focused on applications related to electrical conductivity and nonlinear optics. The attendance was well balanced with a blend of researchers from academic, industrial, and government labs, and including synthetic chemists, physical chemists, physicists, materials scientists, and theoreticians. The Workshop provided an especially timely opportunity to discuss the important progress that has taken place in the field of Conjugated Polymers in the late eighties as well as the enormous potential that lies in front of us. Among the recent significant developments in the field, we can cite for instance: (i) The discovery of novel synthetic routes affording conjugated polymers -that are much better characterized, especially through control of the molecular weight; - that can be processed from solution or the melt; the early promise that conducting polymcrs would constitute materials combining the electrical conductivities of metals with the mechanical properties of plastics is now being realized; -that can reach remarkably high conductivities.

The authors illustrate the basic physics and materials science of conjugated polymers and their interfaces, particularly, but not exclusively, as they are applied to polymer-based light emitting diodes. The approach is to describe the basic physical and associated chemical principles that apply to these materials, which in many instances are different from those that apply to their inorganic counterparts. The main aim of the authors is to highlight specific issues and properties of polymer surfaces and interfaces that are relevant in the context of the emerging field of polymer-based electronics in general, and polymer-based light emitting diodes in particular. Both theoretical and experimental methods used in the study of these systems are discussed. This book will be of interest to graduate students and research workers in departments of physics, chemistry, electrical engineering and materials sciences studying polymer surfaces and interfaces and their application in polymer-based electronics.