Conjugated Polymers: The Novel Science and Technology of Highly Conducting and Nonlinear Optically Active Materials

ISBN-13: 9789401055369 / Angielski / Miękka / 2012 / 624 str.

J. L. Bredas; R. Silbey

Opis

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."

Recenzje

` The book ought to be compulsory reading for anybody proposing to work in the area and should be followed by a short exam before a `practitioners licence' is issued. '
Chemistry & Industry
'This book is a recommended addition to scientific libraries and to scientists interested in remaining abreast of recent advances....' Polymers News 17 1992

Spis treści

Conjugated Polymers: The Interplay Between Synthesis, Structure, and Properties.- 1. Introduction.- 2. Structural Features of Conjugated Polymers.- 3. Polymer Synthesis: Basic Methods.- 3.1 Step-Growth Polymerization.- 3.2 Chain-Growth Polymerization.- 3.3 Ring-Opening Polymerization.- 4. Direct Synthetic Methods.- 4.1 Electrochemical Synthesis.- 4.2 Synthesis by Step-Growth Polymerization.- 4.2.1 Polyaniline (PAN).- 4.2.2 Poly(Phenylene Sulfide).- 4.2.3 Polythiophene and its Derivatives.- 4.2.4 Other 5-membered Heterocyclic Derivatives.- 4.2.5 Polyparaphenylene (PPP).- 4.2.6 Polysilanes.- 4.2.7 Polymers of Phthalocyanines.- 4.2.8 Other Conjugated Metal Coordination Polymers.- 4.2.9 Ladder Polymers.- 4.3 The Unusual Topochemical Polymerization to form Polydiacetylenes.- 4.4 Chain-Growth Polymerizations.- 4.4.1 Polyacetylene via Ziegler-Natta Polymerization.- 4.4.2 Ring-Opening Metathesis Polymerization Routes to Polyacetylenes.- 5. Polymers from precursors.- 5.1 Polyparaphenylene (PPP).- 5.2 Poly(Phenylene Vinylene) (PPV) and Other Vinylene Polymers.- 5.3 Precursors to Polyacetylene.- 6. Extentions of these Methods in the Synthesis of “Small-Bandgap” Polymers.- 7. Conjugated Polymer Matrices.- 8. Conclusions and Caveats.- Acknowledgements.- References.- Properties of Highly Conducting Polyacetylene.- 1. Introduction.- 2. Sample Synthesis, Morphology and Properties.- 2.1 Standard Routes of Synthesis.- 2.2 Naarmann-Type Polyacetylene.- 3. Conductivity: Experimental.- 3.1 The Standard Four-Probe and Montgomery Techniques.- 3.2 Test of Sample Homogeneity.- 3.3 Conductivity Measurement.- 3.4 Sample Preparation.- 4. Conductivity Measurements: Experimental Results.- 4.1 General Remark.- 4.2 Temperature Dependence of ? and ??.- 4.3 Conductivity at Very Low Temperatures (14mK – 4.2 K).- 4.4 Anisotropy and Stretching Ration.- 4.5 Aging Effects in ?(T).- 4.6 Anisotropy and Aging.- 4.7 Dependence of ?(T) on the Dopant Concentration.- 4.8 Doping with FeCl3.- 4.9 Pressure Dependence.- 5. Discussion of ?(T).- 5.1 Experimental Prerequisites for a Model of Charge Transport for T > 400 mK.- 5.2 The Failure of Conventional Models.- 5.3 Description with the Sheng Formula.- 5.4 Limits of the Applicability of Sheng’s Model.- 5.4.1 Low Temperature Limit.- 5.4.2 Image Charge Correction Parameter A.- 5.4.3 Possible Temperature Dependence of ?$$\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{\infty }$$.- 5.4.4 Paasch’s Approach.- 5.5 Evaluation within a Phenomenological Model.- 5.6 Influence of the Barriers on ? (300 K).- 5.7 The Influence of Phonon Scattering on the Conductivity.- 5.8 Low Temperature Behaviour and Aging.- 5.8.1 Describing ?(T) with Sheng’s Formula.- 5.8.2 Influence of Finite Chain Lenghts.- 5.9 Conclusions.- 6. Morphology and Charge Transport.- 6.1 SEM on Freshly-Prepared Samples.- 6.1.1 Sample Preparation for SEM.- 6.1.2 Results.- 6.2 Local Density and Bulk Density.- 6.3 Geometrical and Electrical Anisotropy.- 6.4 Influence of Oxygen Aging and Iodine Doping.- 6.4.1 Oxidation by Oxygen (“Aging”).- 6.4.2 Oxidation by Iodine (“Doping”).- 6.4.3 Charging Effects.- 6.5 TEM on Individual Polyacetylene Fibrils.- 6.5.1 Experimental.- 6.5.2 Results.- 7. Conductivity Barriers and Morphology: a Comparison.- 8. Summary and Outlook.- Acknowledgements.- Literature.- Electronic Properties of Heavily Doped Trans-Polyacetylene.- 1. Introduction.- 2. Models for the Metallic State of Heavily Doped Trans-(CH)x.- 3. Methodology.- 3.1 Hamiltonian.- 3.2 Self-Consistent Calculation Scheme.- 3.3 Description of the Optimized Systems.- 3.4 Polaron Lattice.- 3.5 Density of States.- 4. Results and Discussion.- 4.1 Optimized Geometry using the Conwell-Mizes-Jeyadev Potential.- 4.2 The Effect of Intra-Chain Electron-Electron Interactions.- 4.3 Disordered System.- 4.4 Polaron Lattice.- 4.5 Evolution of the Energy Gap as a Function of Doping Level.- 4.6 Density of States.- 5. Summary and Conclusion.- Acknowledgements.- References.- Solution Processing of Conducting Polymers: Opportunities for Science and Technology.- I. Introduction.- A. Conducting Polymers: Materials with a Unique Combination of Electrical and Mechanical Properties.- B. Conducting Polymers: Approaches to Processing.- C. Blends of Conducting Polymers with Saturated Polymers.- II. Conducting Polymers in Solution.- A. Electronic Structure (and Conformation) of the Neutral Polymers in Solution.- B. Electronic Structure (and Conformation) of the Doped Polymers in Solution.- III. Electrical and Mechanical Properties of Oriented Poly(3-alkylthiophenes) Processed from Solution.- A. Fiber Spinning and Drawing.- B. Characterization of the Drawn P3OT Fibers.- C. Effect of Side-Chain Length.- IV. Gels and Blends of the P3AT’s Processed from Solution.- A. Conducting Polymer Blends of Soluble Polythiophene Derivatives in Polystyrene.- B. Conducting Polymer Gels: A Self Assembling Conducting Network with Remarkably Low Percolation Threshold.- V. Electrical and Mechanical Properties of Polyaniline and Blends of Polyaniline with PPTA Processed from Solution in Sulfuric Acid.- A. Preparation of the PANI/PPTA Blends and PANI/PPTA Fiber Spinning.- B. Properties of the PANI/PPTA Fibers.- VI. Electrical and Mechanical Properties of PTV and PDMPV.- A. Preparation of Precursor Polymers, Fiber Spinning, Drawing and Conversion of PTV and PDMPV.- B. Electrical and Mechanical Properties of PTV.- C. Electrical and Mechanical Properties of PDMPV.- VII. Mechanical and Electrical Properties of Polyacetylene Films Oriented by Tensile Drawing.- A. Polymerization and Tensile Drawing.- B. X-Ray Diffraction.- C. Mechanical Properties.- D. Electrical Conductivity.- VIII. Correlation between Electrical Conductivity and Mechanical Properties.- IX. Conclusion.- Acknowledgement.- References.- The Polyanilines: Model Systems for Diverse Electronic Phenomena.- 1. Introduction.- 2. Leucoemeraldine Base (LEB).- 3. Ring Rotation Polarons and Solitons.- 4. Emeraldine Base.- 5. Pernigraniline Base.- 6. “Metallic” Polyaniline.- 7. Effects of Derivitization.- 8. Summary.- 9. Acknowledgement.- 10. References.- Structural Characterization of Conjugated Polymer Solutions in the Undoped and Doped State.- 1. Introduction.- 2. Polymer Solutions.- 2.1 Models for Single Chains.- 2.1.1 Ideal Chain.- 2.1.2 Real Chain in Good Solvent.- 2.1.3 Chain with Local Stiffness: Kratky-Porod-Model.- 2.2 Notion of Theta and Good Solvent for Linear Saturated Polymer.- 2.2.1 Mean Field Picture.- 2.2.2 Osmotic Pressure.- References.- 3. Structural Studies with Small Angle Scattering.- 3.1 Basic Principles.- 3.2 Scattering at Small Angle.- 3.3 Small Angle Scattering from Polymers in Solution.- 3.3.1 Incompressibility and Contrast Factor.- 3.3.2 Form Factor.- 3.4 Models for Polymer Chains.- 3.4.1 Ideal Chains.- 3.4.2 Chain in Good Solvent, Flexible Chain with Interactions.- 3.4.3 Scattering Function of Chain with Persistence Length.- 3.5 Scattering Measurements in Real Polymer/Solvent Systems.- 3.5.1 Polydispersity Effect.- 3.5.2 Models for Chain Cross Section.- References.- 4. Soluble Conjugated Polymers.- 4.1 Conjugated Polymers with Substituents.- 4.1.1 Substituted Polyacetylenes.- 4.1.2 Poly-n-alkylthiophenes.- 4.1.3 Polydiacetylenes.- 4.2 Diblock Copolymers and Graft Copolymers.- 4.2.1 Graft Copolymer.- 4.2.2 Sequence of Block-Copolymer.- References.- 5. Polydiacetylenes.- 5.1 Introduction.- 5.2 Statistical Conformation in Good Solvent: Yellow Solution.- 5.3 Origin of. the Blue and Red Shifts in Good Solvent: Chain Conformation and Solvatochromism.- 5.4 Color Transition: Aggregation versus Single Chain Process.- References.- 6. Study of Dopable Polymers: PANI and Poly-n-Alkylthiophenes.- 6.1 Doped Polymers in the Solid Phase.- 6.2 Doped Polymers in Solution: Poly-n-Alkylthiophene.- 6.2.1 Structure of Poly-3-butylthiophene in the Neutral State.- 6.2.2 Charged Poly-n-alkylthiophene in Solution.- References.- 7. Does Conjugated Polymer Behave Like Saturated One.- 7.1 Conformation of Soluble Conjugated Polymers: Origin of the Local Rigidity.- 7.1.1 Thermal behavior of the PDA PTS12 in Good Solvent.- 7.1.2 Experimental Evidence of the Influence of the Side-Group Extension.- 7.2 Aggregation Process for Conjugated Polymers.- 7.2.1 Observed Conformations for Polymers in Good Solvent.- 7.2.2 Model for Conjugated Polymers.- Acknowledgement.- References.- Processable Conducting Poly(3-Alkylthiopenes).- 1. Introduction.- 2. Synthesis.- 2.1 Monomer Synthesis.- 2.2 Polymerization.- 3. Characterization.- 3.1 Infrared Spectroscopy.- 3.2 NMR.- 3.3 Elemental Analysis.- 3.4 Thermal Analysis.- 3.5 Molecular Weight.- 3.6 Optical Spectra.- 3.7 X-Ray Diffraction.- 4. Processability-polymer Blends.- 4.1 Processability.- 4.2 Polymer Blends.- 5. Electronic Structure and Conformational Excitations.- 5.1 Electronic Structure.- 5.2 Conformational Excitations: Thermochromism and Solvatochromism.- 6. Doping and Stability.- 6.1 Methods of Doping.- 6.2 Conductivity.- 6.3 Dedoping.- 7. Transport Properties.- 7.1 Field Effect Transistors for Transport Property Studies.- 7.2 Poly(3-Alkylthiophene) Blends.- 8. Stretch Orientation of Poly(3-Alkylthiophenes).- 9. Applications.- 9.1 Applications through Processability.- 9.2 Electronic Devices: Transistors and Diodes.- 9.3 Nonlinear Optical Properties.- 10. Conclusions.- Acknowledgements.- References.- Controlled Molecular Assemblies of Electrically Conductive Polymers.- 1. Introduction.- 2. Fabrication of Monolayer and Multilayer Thin Films of Electrically Conductive Polymers.- 3. Molecular and Supermolecular Organizations of LB Films Containing Conducting Polymers.- 3.1 X-Ray Diffraction Studies.- 3.2 Orientation Studies by FTIR.- 3.2.1 Orientation Studies of LB Films Fabricated with the Poly(3-alkylthiophenes).- 3.2.2 Orientation Studies of LB Films Fabricated with Surface Active Pyrroles and Polypyrrole.- 3.3 Orientation Studies by NEXAFS.- 4. Electrical Properties of LB Films Containing Conducting Polymers.- 4.1 In-Plane and Transverse Conductivities.- 4.2 Dielectric Properties.- 4.3 Evaluation of Electroactive LB Films as Active Components of Thin Film Devices.- 5. Conclusions.- 6. Acknowledgements.- 7. References.- Electronic Properties of Linear Polyenes.- 1. Introduction.- 2. Terms and Concepts.- 2.1 Electronic States.- 2.2 Vibronic Spectra.- 3. Overview of Polyene Singlet States.- 4. Interpretative Model.- 5. The Ground State S0 (l1Ag).- 5.1 Geometry.- 5.2 Vibrational Frequencies.- 6. The Lowest Energy Excited Singlet State S1 (21Ag).- 6.1 Representative Spectra.- 6.2 S, Excitation Energies.- 6.2.1 Conformational Dependence.- 6.2.2 Dependence on Local Polarizability.- 6.3 S1 Vibronic Development.- 6.4 S1 Dynamical Behavior.- 7. The Strongly Allowed Excited Singlet State S2 (11Bu).- 7.1 Representative Spectra.- 7.2 S2 Excitation Energies.- 7.2.1 Conformation Dependence.- 7.2.2 Dependence on Local Polarizability.- 7.3 S2 Vibronic Development.- 7.4 Relaxation Energy.- 7.5 S0-S2 Transition Dipoles.- 8. Concluding Remarks.- 9. Acknowledgement.- 10. References.- Vibrational Spectroscopy of Polyconjugated Aromatic Materials with Electrical and Non Linear Optical Properties - A Guided Tour.- 1. Introduction.- 2. Spectroscopy vs. Material Science.- 3. Spectroscopic Observables.- 3.1 Vibrational Frequencies.- 3.2 Infrared Absorption Intensities.- 3.3 The Raman Spectra.- 4. The Vibrational Force Field. Classical vs. Quantum Mechanical Calculations.- 5. Spectroscopic Characteristics Peculiar to Poly-conjugated Materials.- 5.1 Materials in the Pristine (Insulating) State.- 5.2 Materials in the Doped (Electrically Conducting) State.- 5.3 Materials in the Photoexcited State.- 6. Theoretical Aspects of the Vibrational Spectra of Poly-conjugated Molecules.- 7. Worked-Out Study Cases.- 8. Polypyrrole.- 8.1 Structure, Symmetry and ECC Theory.- 8.2 Calculations and Comparison with the Experiments.- 8.3 Raman Spectrum of Doped PPy.- 8.4 Characterisation of PPy.- 9. Polythiophene.- 9.1 Experimental Data.- 9.2 The Structure of PTh and of its Oligomers.- 9.3 Vibrational Analysis.- 9.4 Structural Characterisation of PTh.- 10. Polyalkylthiophenes.- 10.1 Structure, Group Theory and Spectroscopic Predictions.- 10.1.1 Perfect Planar Structure.- 10.1.2 Conformationally Distorted Structure.- 10.2 EEC Theory.- 10.3 Spectroscopy and Structure of Polyalkyl-Thiophenes.- 10.4 Conformation of the Alkyl Chains.- 10.5 Structure and Thermal Behaviour of Polyalkylthiophenes.- 11. Polyparaphenylene Vinylene.- 11.1 Spectroscopic Data.- 11.2 Structure and Group Theory.- 11.3 Effective Conjugation Length and Molecular Chain Length from Optical Data.- 11.4 Group Theory and ECC Theory.- 11.5 Structure of PPV from Spectroscopy.- 12. Conclusions.- Acknowledgement.- References.- Third Order Nonlinear Optical Effects in Conjugated Polymers.- 1. Introduction.- 1.1 Nonlinear Pplarization.- 1.2 Origin of Second Order Hyperpolarizability.- 1.3 Coherent Nonlinearities.- 1.4 Second Order Hyperpolarizability of Centro-symmetric and Non-Centrosymmetric Molecules. Influence of Polymer Length.- 1.4.1 Centrosymmetric Molecules.- 1.4.2 Non-Centrosymmetric Molecules.- 1.5 Conformational Effects.- 2. Thin Film Preparation Methods.- 2.1 Langmuir-Blodgett Technique.- 2.2 Solution Casting.- 2.3 Vacuum Evaporation-Epitaxy.- 3. Principal x(3) Characterization Techniques.- 3.1 Third Harmonic Generation.- 3.1.1 Third Harmonic Generation in Nonabsorbing Stratified Media.- 3.1.2 Harmonic Generation in Absorbing Media.- 3.1.3 Multiple Reflections.- 3.1.4 Harmonic Generation in Focused Laser Beams.- 3.2 Third Harmonic Generation in Thin Films and in Solutions.- 3.2.1 Thin Film Case.- 3.2.2 THG in Polymer Solutions.- 3.3 Electric Field Induced Second Harmonic Generation.- 3.3.1 Thin Film Case.- 3.3.2 Centrosymmetric Molecules in Solution.- 3.3.3 Non-Centrosymmetric Molecules in Solution.- 3.4 Four Wave Mixing Experiments.- 3.5 Optical and Quadratic Kerr Effect.- 3.6 Optical Stark Effect.- 3.7 Saturation Absorption.- 3.8 Photoinduced Absorption.- 4. Frequency Spectrum and Resonance Effects in x(3).- 4.1 Frequency Variation of x(3): Modelisation.- 4.2 Determination of µ01.- 4.3 Frequency Variation of x(3) (-3?;?,?,?) and x(3) (-2?;?,?,O).- 5. Multiphoton Resonances.- 6. Nonlinear Optical Dichroism.- 7. Perspectives of Applications.- 7.1 Frequency Conversion.- 7.2 Optical Switching and Directional Couplers.- 7.3 Optical Bistability.- References.- The Semiconductor Device Physics of Polyacetylene.- 1. Introduction.- 2. Electronic Excitations in Conjugated Polymers.- 3. Polymer Processing and Device Fabrication.- 3.1 The Durham Precursor Route to Polyacetylene.- 3.2 Device Fabrication.- 4. Electronic Properties of Durham-Route Polyacetylene.- 4.1 Electronic Structure.- 4.2 Electronic Transport.- 4.3 Electromodulation of Optical Absorption.- 5. Schottky Barrier Diodes.- 5.1 The Schottky Barrier.- 5.2 Electrical Characteristics.- 5.3 Electro-Optic Properties.- 5.4 Electronic States in the Polyacetylene Schottky Barrier.- 6. MIS Structures.- 6.1 The Field-Effect Device.- 6.2 Electrical Characterisation of MIS Structures.- 6.2.1 Silicon Dioxide as Insulator.- 6.2.2 Polymer Insulator Layers.- 6.3 Electro-Optical Properties of the MIS Structure.- 6.3.1 Electronic Excitations of Solitons.- 6.3.2 Vibrational Excitations of Solitons.- 6.4 Modelling of Electronic Structure in the Accumulation Layer.- 7. MISFET Devices.- 7.1 Fabrication.- 7.2 Poly n-Silicon Source and Drain Contacts.- 7.3 Charge Transport in Polyacetylene.- 8. General Discussion.- Acknowledgements.- References.