CONDUCTING POLYMERS, FUNDAMENTALS AND

APPLICATIONS A Practical Approach

by

Prasanna Chandrasekhar Ashwin-Ushas Corp., Inc.

*

KLUWER ACADEMIC PUBLISHERS Boston / Dordrecht / London

TABLE OF CONTENTS

LIST OF COMMON ABBREVIATIONS xxv

FOREWORD, Lawrence Dalton xxxiii

PREFACE xxxv

PART I: FUNDAMENTALS 1

CHAPTER 1: BASICS OF CONDUCTING POLYMERS (CPs) 3

1.1 WHAT ARE CONDUCTING POLYMERS (CPs)? 4 1.1.1 Definitions and Examples 4 1.1.2 Excluded Materials Classes (Those Not Treated as CPs in this

Book) 7

1.2 HISTORICAL 9

1.3 BASIC CHARACTERISTICS OF CPs, DOPING AND STRUCTURE 10

1.3.1 Conductivity Classification of Materials 10 1.3.2 Doping and Dopants 12 1.3.3 Doping Types 15 1.3.4 Real and Idealized Structures 16

1.4 BASICS OF CP SYNTHESIS 16 1.4.1 Categories and Classes of Syntheses 16 1.4.2 Representative Synmeses- Chemical 17 1.4.3 Representative Synmeses- Electrochemical 20 1.4.4 Simple Representation of Mechanisms 20

PROBLEMS AND EXERCISES 22

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CHAPTER 2: SEMICONDUCTOR MODELS FOR CPs 23

2.1 CONVENTIONAL SEMICONDUCTORS AND CPs 23 2.1.1 Conventional Semiconductors 23 2.1.2 CPs as Semiconductors 25

2.2 STRUCTURAL DISTORTIONS: POLARONS, BIPOLARONS AND

SOLITONS 26

2.3 BAND STRUCTURE EVOLUTION 34

2.4 DENSITIES OF STATES AND WAVEVECTOR REPRESENTA­

TIONS 37

2.5 CORRELATION OF OPTICAL SPECTRA TO BAND STRUCTURE . . 38

2.6 THEORETICAL AND PRACTICAL ASPECTS 41

PROBLEMS AND EXERCISES 41

CHAPTER 3: BASIC ELECTROCHROMICS OF CPs 43

3.1 BASICS OF ELECTROCHROMISM AND SPECTROELECTRO-CHEMISTRY OF CPs 43 3.1.1 Basics 43 3.1.2 Spectral Regions 44 3.1.3 Elementary Electrochemistry of CPs as Basis for Electro-

chromism 45 3.1.4 Basic Methodology for Transmission- and Reflectance- Mode

Electrochromism 46

3.2 UV-VIS-NIR AND IR SPECTROELECTROCHEMICAL MEASUREMENTS 48 3.2.1 Transmission-Mode SPELs 48 3.2.2 Reflection-Mode Data 52 3.2.3 IR-Region Data 56

3.3 OTHER ELECTROCHROMIC PARAMETERS OF INTEREST 65

3.4 OTHER MEASUREMENTS 72

PROBLEMS AND EXERCISES 75

CONDUCTING POLYMERS: Fundamentals and Applications ix

CHAPTER 4: ELECTROCHEMISTRY OF CPs 77

4.1 BASICS 78

4.1.1 Introduction 78 4.1.2 Basic Methodology 78 4.1.3 Electrolytes and Electrodes 79

4.2 BASIC VOLTAMMETRIC PARAMETERS AND INFORMATION OF INTEREST 81 4.2.1 Cyclic Voltammograms (CVs) 81 4.2.2 Electrochemical Windows 82 4.2.3 Scan Rate Dependencies 83 4.2.4 Other Parameters From CVs, Peak Broadening 83 4.2.5 Surface-Active Behavior 84 4.2.6 Charge Capacities 86 4.2.7 Dopant and Structural Relationships 86 4.2.8 Reversibility 89

4.3 SOLVENT AND pH EFFECTS, MIXED SOLVENTS, DOPANTS 89

4.4 RELATION WITH SEMICONDUCTOR PROPERTIES 92

4.5 OTHER VOLTAMMETRIC METHODS 94

4.6 CA, CC AND DIFFUSION COEFFICIENTS 94

4.7 COMPLEX FILM THICKNESS AND DOPANT EFFECTS 96

4.8 MODIFIED ELECTRODES 98

PROBLEMS AND EXERCISES 98

CHAPTER 5: ADVANCED POLYMERIZATION CONCEPTS 101

5.1 ELECTROCHEMICAL POLYMERIZATION 102 5.1.1 Mechanisms 102

5.1.1.1 Generic Electropolymerization Mechanism 102 5.1.1.2 Factors Favoring Polymerization and No Poly­

merization 104 5.1.1.3 Mechanistic Notation and Rate Expressions 107

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5.1.2 Solvents and Electrodes 110 5.1.3 Potentiostatic, Galvanostadc Polymerizations, Threshold

Concentrations I l l 5.1.4 Dopants 112 5.1.5 Electrochemical Monitoring of Polymerization 113

5.2 CHEMICAL POLYMERIZATION 115 5.2.1 Mechanisms and General 115 5.2.2 Optimization in Solution Polymerizations 117 5.2.3 Synopsis of Chemical Syntheses 118 5.2.4 Unique Chemical Polymerization Methods 122

5.3 DOPANTS, AND ALTERNATIVE DOPING TECHNIQUES 124 5.3.1 Common Dopants 124 5.3.2 Uncommon or Unusual Dopants 126 5.3.3 Alternative Doping Techniques 127

5.4 TEMPLATE-BASED POLYMERIZATIONS 129

5.5 NANOSCALE POLYMERIZATIONS 136

5.6 TRUE COPOLYMERIZATIONS 138

5.7 BULK AND COMMERCIAL PRODUCTION 140

PROBLEMS AND EXERCISES 142

CHAPTER 6: CONDUCTION MODELS FOR CPs 143

6.1 INTRODUCTION AND GENERAL ASPECTS 144 6.1.1 Experimental Measurements Substantiating Conduction

Models 144 6.1.2 Nature of Conduction and Relation with CP Morphology . . . 145 6.1.3 Temperature, Frequency, Doping Dependencies 148

6.1.3.1 Temperature Dependencies 148 6.1.3.2 Frequency Dependencies 148 6.1.3.3 Doping Dependencies 148

6.1.4 Practical Aspects 149

6.2 CONDUCTION MODELS 150 6.2.1 Mott Variable Range Hopping (VRH) Model 150 6.2.2 Sheng Model 152

CONDUCTING POLYMERS: Fundamentals and Applications xi

6.2.3 Kivelson and Other Models 152 6.2.4 Relationship of All Models 154

6.3 EXPERIMENTAL CORRELATIONS 155 6.3.1 General 155 6.3.2 Temperature Dependencies 155 6.3.3 Frequency Dependencies, Microwave Measurements 159 6.3.4 Thermopower and Hall Effect Measurements 162 6.3.5 Pressure Dependencies 164 6.3.6 Stretching, Anisotropy, Crystallinity, Molecular Weight

Effects 167 6.3.7. Activation Energies and Mobilities 169 6.3.8 Minor Structural Effects 171

PROBLEMS AND EXERCISES 172

CHAPTER 7: THEORETICAL TREATMENTS OF CPs 173

7.1 AIMS OF THIS CHAPTER 174

7.2 ONE-DIMENSIONAL SYSTEMS AND PEIERLS INSTABILITY . . . 174

7.3 OVERVIEW OF THEORETICAL METHODS USED 175

7.4 EXTENDED HÜCKEL AND RELATED METHODS 177

7.5 THE VEH METHOD 178

7.6 AB INITIO, COMBINATION AB INITIO/SEMIEMPIRICAL STUD­

IES 183

7.7 METHODS USING SSH HAMILTONIANS 185

7.8 METHODS CONSIDERING e-e, e-p CORRELATIONS 186

7.9 APPENDIX 7-1: SELECTED CALCULATED BAND STRUCTURES 189

7.10 APPENDIX 7-2: SELECTED METHODOLOGY, CALCULATION DETAILS, AND RELEVANT EQUATIONS 196 7.10.1 Extended Hiickel (EH) 196 7.10.2 LCAO/ETB (Extended Tight Binding) 197

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7.10.3 VEH 197 7.10.4 Strictly Ab Initio Methods 199 7.10.5 Representative Combination Ab Initio/Semi-Empirical

Methods 199 7.10.6 The SSH Hamiltonian 199 7.10.7 Methods Considering e-e, e-p Correlations 200

PROBLEMS AND EXERCISES 206

CHAPTER 8: SOLUBILITY AND PROCESSING OF CPs 207

8.1 INTRODUCTORY REMARKS AND TRULY SOLUBLE CPs 208 8.1.1 Note on Commonality with Material in Other Chapters . . . . 208 8.1.2 Truly Soluble and Processible CPs 208 8.1.3 Most Common Processing Methods 208

8.2 SOLUTIONS IN UNUSUAL OR DIFFICULT SOLVENTS 209

8.3 TEMPLATE BASED AND SULFONATED CPs 210 8.3.1 Template Based "Soluble" CPs 210 8.3.2 "Self-Doped" and Other Sulfonated CP Systems 213

8.4 LONG CHAIN ALKYL SUBSTITUTED POLY(THIOPHENES) . . . . 215

8.5 POLY(DIACETYLENES) AS PROCESSIBLE CPs 215

8.6 USE OF OTHER SOLUBILIZING GROUPS 216

8.7 PROCESSING AND COATING OF CPs VIA in situ POLYMERIZA­

TION 218 8.7.1 General 218 8.7.2 Textile and Fiber Coating 218

8.8 MELT AND OTHER HEAT PROCESSIBILITY 219

8.9 TECHNIQUES USING COLLOIDAL SOLUTIONS 221

8.10 PRECURSOR ROUTES 223

8.11 LANGMUIR-BLODGETT FILMS OF CPs 223

8.12 DIRECT VAPOR DEPOSITION 226

CONDUCTING POLYMERS: Fundamentals and Applications ХШ

8.13 OTHER NEW DEPOSITION METHODS 226

PROBLEMS AND EXERCISES 227

CHAPTER 9: STRUCTURAL ASPECTS, MORPHOLOGY AND FIBER/ FILM PROCESSING 229

9.1 GENERAL CONSIDERATIONS IN MORPHOLOGY 230 9.1.1 Idealized and Real Structures, Chain Defects and Order . . . . 230 9.1.2 Polymerization Conditions 230 9.1.3 Rotational Barriers 232 9.1.4 Molecular Weight (MWt) 232 9.1.5 Fibrillar and Globular Morphology 234 9.1.6 Doping Effects 235 9.1.7 Effects of Fundamental Structure and Substituents 237

9.2 FIBERS AND ORIENTED FILMS 238 9.2.1 Preparation: Fibers 238

9.2.1.1 General Considerations in Fiber Preparation . . . . 238 9.2.1.2 Representative Procedures in Detail 239

9.2.2 Preparation: Oriented Films 241 9.2.3 Enhancement of Conductivity, Conductivity Anisotropy . . . . 242 9.2.4 Mechanical Properties 243 9.2.5 Crystallinity 245 9.2.6 True Single-Crystal Character 247

9.3 THERMOCHROMISM AND SOLVATOCHROMISM 248

PROBLEMS AND EXERCISES 251

CHAPTER 10: "COMPOSITES" (BLENDS) AND COPOLYMERS 253

10.1 INTRODUCTION AND DEFINITIONS 254 10.1.1 Definitions 254 10.1.2 Synopsis of Types of Syntheses 256

10.2 IN SITU CHEMICAL POLYMERIZATIONS 256 10.2.1 Chemical Polymerization via Sorption of Monomer 256 10.2.2 Chemical Polymerization via Sorption of Oxidant 257 10.2.3 Solution Evaporative Polymerization 258 10.2.4 Catalytic and Omer In Situ Chemical Polymerization 259

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10.3 IN SITU ELECTROCHEMICAL POLYMERIZATIONS 261

10.4 DIRECT POLYMER BLENDS 262 10.4.1 Blending in Solution 262 10.4.2 Melt-Blending 263

10.5 COMPOSITE FIBERS 264

10.6 TRUE COPOLYMERS 265

10.7 INTERPENETRATING POLYMER NETWORKS 272

PROBLEMS AND EXERCISES 272

CHAPTER 11: CHARACTERIZATION METHODS AND SALIENT RESULTS: PART 1 275

11.1 INTRODUCTION, OUTLINE OF SKELETAL CHARACTERIZA­TION 276

11.2 CONDUCTIVITY AND RELATED MEASUREMENTS 277 11.2.1 Ex-Situ DC Conductivity of Powders, Films and Fibers . . . 277 11.2.2 In-Situ DC Conductivity 280 11.2.3 Electrochemical Impedance Spectroscopy (EIS) and AC

Conductivity 281 11.2.4 Thermopower Measurements 286

11.3 INFRARED MEASUREMENTS 286

11.4 MOLECULAR WEIGHT 289 11.4.1 Indirect Methods 289 11.4.2 Gel Permeation Chromatography (GPC) 290 11.4.3 Viscosity 290 11.4.4 Light Scattering 290

11.5 RAMAN SPECTROSCOPY 291

11.6 THERMAL AND ENVIRONMENTAL STABILITY MEASURE­MENTS 297 11.6.1 Thermogravimetric Analysis (TGA) 297 11.6.2 Differential Scanning Calorimetry (DSC) 301 11.6.3 Other Thermal and Environmental Stability Test Methods . . 303

CONDUCTING POLYMERS: Fundamentals and Applications xv

11.7 X-RAY PHOTOELECTRON SPECTROSCOPY 306

11.8 NUCLEAR MAGNETIC RESONANCE METHODS 310

11.9 ESR 315

11.9.1 Basics of ESR of CPs 315 11.9.2 P(Py) and Poly(thiophenes) 316 11.9.3 Poly(acetylene) 319 11.9.4 P(ANi)s 320 11.9.5 Photo-Induced ESR 321 11.9.6 Other CPs 322

11.10 ENDOR 323

11.11 ELECTRON ENERGY LOSS SPECTROSCOPY (EELS) 324

PROBLEMS AND EXERCISES 326

CHAPTER 12: CHARACTERIZATION METHODS AND SALIENT RESULTS: PART 2 329

12.1 MICROWAVE PROPERTIES 330 12.1.1 Interest in CPs, Properties Covered, Frequencies 330 12.1.2 Parameters of Interest, and Cavity Perturbation Measure­

ments 330 12.1.3 Network Analyzer Based Methods 332 12.1.4 Transmission and Reflection Measurements 333 12.1.5 EMI Shielding Effectiveness (EMI-SE) Measurements . . . . 333 12.1.6 Radar Cross Section (RCS) 334 12.1.7 Salient Results 334

12.2 PHOTO/ELECTRO-LUMINESCENCE, PHOTO-INDUCED PROP­ERTIES 339 12.2.1 Methods 339 12.2.2 Salient Results 340

12.3 THIRD ORDER NONLINEAR OPTICAL (NLO) PROPERTIES 351 12.3.1 The NLO Effect and Practical Requirements 351 12.3.2 Methodology 352 12.3.3 Salient Results: Third Order NLO Effects 353 12.3.4 Salient Results: Second Order NLO Effects 361 12.3.5 Salient Results: Decay Times of Excited States 361

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12.4 MAGNETIC SUSCEPTIBILITY 363

12.5 MISCELLANEOUS METHODS 366

Problems and Exercises 369

CHAPTER 13: CLASSES OF CPs: PART 1 371

Note on Chapter Focus 372

13.1 POLY(ACETYLENES) (P(Ac)s) 372

13.1.1 Simple Syntheses and Basic Properties 372 13.1.2 Doping of P(Ac) 373 13.1.3 Orientation of P(Ac) 374 13.1.4 Special Syntheses 375 13.1.5 Substituted P(Ac)s 376

13.2 POLY(DIACETYLENES) (P(DiAc)s) 377

13.3 POLY(PYRROLES) (P(Py)s) 381 13.3.1 Chemical Polymerizations 381 13.3.2 Electrochemical Syntheses 382 13.3.3 Substituted P(Py)s 383

13.4 POLY(ANILINES) (P(ANi)s) 383 13.4.1 Structure and Nomenclature 383 13.4.2 Representative Chemical Syntheses 385 13.4.3 Electrochemical Synthesis 386

13.5 P(ANi) DERIVATIVES 387

13.6 OTHER POLY(AROMATIC AMINES) 388

PROBLEMS AND EXERCISES 391

CHAPTER 14: CLASSES OF CPs: PART 2 393

Note on Chapter Focus 394

14.1 POLY(THIOPHENES)(P(T)'s) 394 14.1.1 Chemical Syntheses 394

CONDUCTING POLYMERS: Fundamentals and Applications xvii

14.1.2 Electrochemical Syntheses 395 14.1.3 Properties 398

14.2 DERIVATIVES OF POLY(THIOPHENES) 400 14.2.1 P(ITN) and Poly(naphtho[c]thiophene) 401 14.2.2 Poly(thienylene vinylenes) P(TV)s 403 14.2.3 Other Poly(thiophene) (P(T)) Derivatives 406

14.3 POLY(p-PHENYLENE)s (P(PP)s) AND DERIVATIVES 409 14.3.1 Poly(p-phenylene) P(PP) 409 14.3.2 Poly(phenylene vinylene) (P(PV)) 412 14.3.3 Poly(phenylene sulfide) (P(PS)), Poly(phenylene oxide)

(P(PO)) and Related Poly(phenylene chalcogenide)s 420

14.4 POLY(AZULENES) 422

14.5 LADDER POLYMERS: BBL, BBB, PBT, PBO 423

14.6 POLY(QUINOLINES) AND DERIVATIVES 426

14.7 OTHER POLYMERS 428

PROBLEMS AND EXERCISES 428

PART П: APPLICATIONS 431

CHAPTER 15: BATTERIES 433

15.1 TYPES OF BATTERIES INCORPORATING CPs 434 15.1.1 Summary of Applications 434 15.1.2 Advantages of CPs 434 15.1.3 Battery Parameters and Performance 434

15.2 Li SECONDARY BATTERIES 437 15.2.1 Principles 437 15.2.2 Li/CP Batteries 439 15.2.3 Problems Associated with Li/CP Batteries 440

15.3 POLY(ACETYLENE) (P(Ac)) 441

15.4 POLY(PYRROLE) (P(Py)) 442

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15.5 POLY(ANILINE) (P(ANi)) 444

15.6 POLY(THIOPHENES) (P(T)s) 446

15.7 OTHER CPs 446

15.8 NON-Li-BATTERIES 447

15.9 COMMERCIALIZATION OF CP-BASED BATTERIES 449

PROBLEMS AND EXERCISES 452

CHAPTER 16: LIGHT EMITTING DIODES (LEDs) 453

16.1 INTRODUCTION 454

16.2 PRINCIPLES OF CP-BASED LEDs 455

16.3 VARIETIES OF CPs USED 459

16.4 EXEMPLARY DEVICE ASSEMBLY 459

16.5 ADDRESSING PROBLEMS AND TAILORING PERFORMANCE . . 460

16.6 TAILORING OF COLOR 463

16.7 AC-DRIVEN LEDs 473

16.8 LEDs EMITTING POLARIZED LIGHT 475

16.9 SUBMICRON AND OTHER SPECIALTY APPLICATIONS 476

16.10 ADDITIONAL DEVELOPMENTS RELATING TO DEVICE AND

COMMERCIAL APPLICATIONS 477

16.11 "LECs" AND OTHER DEVICE TYPES 480

PROBLEMS AND EXERCISES 482

CONDUCTING POLYMERS: Fundamentals and Applications xix

CHAPTER 17: SENSORS 483

17.1 MODES OF SENSING WITH CPs 484

17.2 CONDUCTOMETRIC-MODE SENSORS 484

17.3 POTENTIOMETRIC SENSING 490

17.4 AMPEROMETRIC SENSING 492

17.5 CONDUCTOMETRIC/AMPEROMETRIC SENSING WITH MICRO

SENSORS 498

17.6 VOLTAMMETRIC SENSING 501

17.7 GRAVIMETRIC-MODE SENSING 503

17.8 OPTICAL-MODE SENSING 504

17.9 OTHER SENSING MODES 506

17.10 COMMERCIAL IMPLEMENTATION 508

PROBLEMS AND EXERCISES 508

CHAPTER 18: ELECTRO-OPTIC AND OPTICAL DEVICES 509

18.1 DEVICE TYPES AND MOTIVATIONS FOR DEVELOPMENT . . . 509

18.2 WAVEGUIDES 510

18.3 OTHER SECOND-ORDER NLO APPLICATIONS 517

18.4 SEMICONDUCTOR/CP (SC/CP) INTERFACES 518

18.5 CP-BASED LASERS 523

18.6 OTHER OPTICAL DEVICES 524

18.7 PRACTICAL IMPLEMENTATION 525

PROBLEMS AND EXERCISES 526

xx Table of Contents

CHAPTER 19: MICROWAVE- AND CONDUCTIVITY-BASED

TECHNOLOGIES 527

19.1 INTRODUCTION, APPLICATIONS COVERED, FREQUENCIES . . 527

19.2 ELECTROMAGNETIC IMPULSE (EMI) SHIELDING 528

19.3 ELECTROSTATIC DISCHARGE AND ANTISTATIC 531

19.4 MICROWAVE ABSORPTION AND RADAR CROSS SECTION (RCS)

REDUCTION 532

19.5 COMPREHENSIVE PROPERTIES' STUDIES 534

19.6 CONDUCTIVE TEXTILES 536

19.7 MICROWAVE SMOKE 539

19.8 MICROWAVE WELDING 540

PROBLEMS AND EXERCISES 541

CHAPTER 20: ELECTROCHROMIC DEVICES 543

20.1 INTRODUCTION AND DEVICE TYPES 543

20.2 VISIBLE-REGION DEVICES 545

20.2.1 Structure 545 20.2.2 Function of Devices, Laboratory vs. Actual Devices 546 20.2.3 Examples of Actual, Functional Devices 548

20.3 IR-REGION DEVICES 554

20.4 OTHER SPECTRAL REGIONS 560

PROBLEMS AND EXERCISES 561

CONDUCTING POLYMERS: Fundamentals and Applications xxi

CHAPTER 21: ELECTROCHEMOMECHANICAL AND CHEMO-

MECHANICAL DEVICES 563

21.1 INTRODUCTION, HISTORY, AND PRINCIPLES 563

21.2 ARTIFICIAL MUSCLES 564

21.3 OTHER ELECTROCHEMOMECHANICAL ACTUATION 567

21.4 CHEMOMECHANICAL ACTUATORS AND SENSORS 570

PROBLEMS AND EXERCISES 571

CHAPTER 22: CORROSION PROTECTION 573

22.1 PRINCIPLES, DRIVING FORCES AND HISTORY 574 22.1.1 Principles of Other Anti-Corrosion Methods 574 22.1.2 Driving Forces Behind Development 574 22.1.3 Principles of CP Anti-Corrosion Coatings 575 22.1.4 Brief Historical Development 577 22.1.5 Advantages of CP Coatings 578

22.2 CANDIDATES AND METHODS 578 22.2.1 Most-Studied Candidates and Coating Methodology 578 22.2.2 Testing Methodology 579

22.3 SALIENT RESULTS 579 22.3.1 P(ANi)'s 579 22.3.2 Other Poly(Aromatic Amines) 585 22.3.3 Other CPs 588

22.4 PROGNOSIS FOR THE FUTURE 588

PROBLEMS AND EXERCISES 589

CHAPTER 23: SEMICONDUCTOR-, LITHOGRAPHY-, AND ELECTRICALLY-RELATED APPLICATIONS 591

23.1 LITHOGRAPHY AND PHOTOPATTERNING 592 23.1.1 Lithography 592

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23.1.2 Other Photopatterning 594 23.1.3 Other Related Applications 596

23.2 PHOTOVOLTAICS, HETEROJUNCTIONS AND PECs 596 23.2.1 Use of CPs in General 596 23.2.2 PVs, Heterojunctions, Diodes 597 23.2.3 Photoelectrochemical Cells (PECs) 609

23.3 CAPACITORS 612

23.4 ELECTROLYTIC AND ELECTROLESS METAL PLATING 616

23.5 CP-BASED "MOLECULAR ELECTRONIC DEVICES" 617

PROBLEMS AND EXERCISES 624

CHAPTER 24: CATALYSIS AND DRUG/CHEMICAL DELIVERY . . . 627

24.1 INTRODUCTION AND COMMON FEATURES 627

24.2 CATALYSIS 628

24.3 DRUG/CHEMICAL DELIVERY 631

PROBLEMS AND EXERCISES 634

CHAPTER 25: MEMBRANES 637

25.1 INTRODUCTION 637

25.2 ION PERMEATION AND EXCHANGE 638

25.3 CHEMICAL/DRUG PERMEATION 640

25.4 GAS SEPARATION 640

PROBLEMS AND EXERCISES 644

LITERATURE CITED 645

CONDUCTING POLYMERS: Fundamentals and Applications xxiii

INDEX 703

ABOUT THE AUTHOR 719