Biomedical Applications of Electroactive Polymer Actuators (eBook)

Federico Carpi, Elisabeth Smela (Herausgeber)

eBook Download: PDF

2009 | 1. Auflage
496 Seiten
Wiley (Verlag)
978-0-470-74468-0 (ISBN)

Infos

Giving fundamental information on one of the most promising families of smart materials, electroactive polymers (EAP) this exciting new titles focuses on the several biomedical applications made possible by these types of materials and their related actuation technologies. Each chapter provides a description of the specific EAP material and device configuration used, material processing, device assembling and testing, along with a description of the biomedical application.

Edited by well-respected academics in the field of electroactive polymers with contributions from renowned international experts, this is an excellent resource for industrial and academic research scientists, engineers, technicians and graduate students working with polymer actuators or in the fields of polymer science.

 

Dr. Ing. Federico Carpi is a postdoctoral researcher at the Interdepartmental Research Center, E. Piaggio, at the University of Pisa (Italy). He gained his degree and PhD at the University of Pisa. His main research interests include the design, the study, the development, the fabrication and the characterization of innovative electromechanical devices based on electroactive polymer (EAP) materials. Dr. Carpi is also founder and co-coordinator for the European Scientific Network for Artificial Muscles.

Elisabeth Smela is an Associate Professor in the Department of Mechanical Engineering at the University of Maryland (USA). She received her BS in physics from MIT and completed her PhD in electrical engineering at the University of Pennsylvania in 1992. She then worked at Linköping University in Sweden and at Riso National Lab in Denmark developing microfabricated conjugated polymer devices. In 1999 she joined the start-up company Santa Fe Science and Technology in New Mexico as Vice President of Research and Development. She joined the faculty of the Department of Mechanical Engineering at the University of Maryland in September 2000. She was awarded the Presidential Early Career Award for Scientists and Engineers (PECASE) in 2004 for research in dielectric elastomer actuators for microrobotics. She also received the DuPont Young Professor Award in 2003, the engineering school's Kent Teaching Award for Junior Faculty in 2004, and the university's Outstanding Invention of 2004. Her research interests are in polymer MEMS and bioMEMS, and more generally in combining organic materials with conventional inorganic materials to make new micro-scale devices.

Inhalt

Biomedical Applications of Electroactive Polymer Actuators 3
Contents 7
Preface 17
List of Contributors 19
Introduction 23
SECTION I POLYMER GELS 27
1 Polymer Gel Actuators: Fundamentals 29
1.1 Introduction and Historical Overview 29
1.2 Properties of Gels 30
1.2.1 Biological Gels 30
1.2.2 Mechanical Properties of Simple, Single-Phase Gels 31
1.2.3 Elastic Moduli 32
1.2.4 Strength 32
1.2.5 Multi-Phase Gels 34
1.2.6 Double Network Gels 35
1.2.7 Transport Properties 36
1.2.8 Drying 37
1.3 Chemical and Physical Formation of Gels 38
1.4 Actuation Methods 41
1.4.1 Thermally Driven Gel Actuators 41
1.4.2 Chemically Driven Gel Actuators 42
1.4.3 Gels Driven by Oscillating Reactions 44
1.4.4 Light Actuated Gels 45
1.4.5 Electrically Driven Gel Actuators 45
1.4.6 Electro- and Magneto-Rheological Composites 47
1.4.7 LC Elastomers 48
1.5 Performance of Gels as Actuators 48
1.6 Applications of Electroactive Gels 52
1.6.1 Gel Valves and Pumps 52
1.6.2 Light Modulators 52
1.6.3 Gel Drug Delivery 53
1.6.4 Gel Sensors 54
1.7 Conclusions 54
References 55
2 Bio-Responsive Hydrogels for Biomedical Applications 65
2.1 Introduction 65
2.2 Chemical Hydrogels 66
2.3 Physical Hydrogels 66
2.4 Defining Bio-Responsive Hydrogels 66
2.5 Bio-Responsive Chemical Hydrogels 68
2.5.1 Actuation Based on Changing the Cross-Linking Density 68
2.5.2 Actuation Based on Changes in Electrostatic Interactions 71
2.5.3 Actuation Based on Conformational Changes 73
2.6 Bio-Responsive Physical Hydrogels 75
2.6.1 Enzyme-Responsive Physical Hydrogels 75
2.7 Electroactive Chemical Hydrogels 78
2.8 Conclusion 79
References 79
3 Stimuli-Responsive and ‘Active’ Polymers in Drug Delivery 83
3.1 Introduction 83
3.2 Drug Delivery: Examples, Challenges and Opportunities for Polymers 84
3.2.1 Oral Drug Delivery Systems 84
3.2.2 Parenteral Drug Delivery 85
3.2.3 Topical and Transdermal Drug Delivery 85
3.2.4 Delivery Challenges for Biomolecular Drugs and Cell Therapeutics 86
3.2.5 Peptides and Proteins 86
3.2.6 Nucleic Acids 87
3.2.7 Cell Delivery 87
3.3 Emerging State-of-the-Art Mechanisms in Polymer Controlled Release Systems 89
3.3.1 Technologies for Controlled Drug Release 89
3.3.2 Polymer–Drug Conjugates 89
3.3.3 Polymer–Protein Conjugates 89
3.3.4 Polymer–Nucleic Acid Conjugates 90
3.3.5 Polymer–Nucleic Acid Complexes 90
3.4 Responsive or ‘Smart’ Polymers in Drug Delivery 95
3.4.1 Soluble Smart Polymers 95
3.4.2 Responsive Polymer–Drug Conjugates 98
3.4.3 Responsive Polymer–Protein Conjugates 98
3.4.4 Responsive Polymers for DNA Delivery 99
3.5 Recent Highlights of Actuated Polymers for Drug Delivery Applications 100
3.6 Conclusions and Future Outlook 102
References 103
4 Thermally Driven Hydrogel Actuator for Controllable Flow Rate Pump in Long-Term Drug Delivery 111
4.1 Introduction 111
4.2 Materials and Methods 112
4.3 Hydrogel Actuator 112
4.3.1 Thermo-Mechanical Gel Dynamics 113
4.3.2 Experimental Results 115
4.4 Pump Functioning 119
4.5 Conclusion 120
References 120
SECTION II IONIC POLYMER–METAL COMPOSITES (IPMC) 123
5 IPMC Actuators: Fundamentals 125
5.1 Introduction 125
5.2 Fabrication 126
5.2.1 Ionic Polymer 126
5.2.2 Plating Methods 127
5.3 Measurement 130
5.4 Performance of the IPMC Actuator 132
5.5 Model 135
5.6 Recent Developments 138
5.7 Conclusion 139
References 140
6 Active Microcatheter and Biomedical Soft Devices Based on IPMC Actuators 143
6.1 Introduction 143
6.2 Fabrication of the IPMC Device 144
6.3 Applications to the Microcatheter 146
6.4 Other Applications 149
6.4.1 Sheet-Type Braille Display 149
6.4.2 Underwater Microrobot 152
6.4.3 Linear Actuators for a Biped Walking Robot 156
6.5 Conclusions 157
References 157
7 Implantable Heart-Assist and Compression Devices Employing an Active Network of Electrically-Controllable Ionic Polymer–Metal Nanocomposites 159
7.1 Introduction 159
7.2 Heart Failure 161
7.3 Background of IPMNCs 162
7.4 Three-Dimensional Fabrication of IPMNCs 163
7.5 Electrically-Induced Robotic Actuation 164
7.6 Distributed Nanosensing and Transduction 166
7.7 Modeling and Simulation 168
7.8 Application of IPMNCs to Heart Compression and Assist in General 171
7.9 Manufacturing Thick IPMNC Fingers 177
7.10 Conclusions 179
References 179
8 IPMC Based Tactile Displays for Pressure and Texture Presentation on a Human Finger 183
8.1 Introduction 183
8.2 IPMC Actuators as a Tactile Stimulator 184
8.3 Wearable Tactile Display 186
8.4 Selective Stimulation Method for Tactile Synthesis 187
8.5 Texture Synthesis Method 189
8.6 Display Method for Pressure Sensation 190
8.6.1 Method 190
8.6.2 Evaluation 190
8.7 Display Method for Roughness Sensation 191
8.7.1 Method 191
8.7.2 Evaluation 192
8.8 Display Method for Friction Sensation 193
8.9 Synthesis of Total Textural Feeling 194
8.9.1 Method 194
8.9.2 Experiments 194
8.10 Conclusions 195
References 195
9 IPMC Assisted Infusion Micropumps 197
9.1 Introduction 197
9.2 Background of IPMCs 198
9.3 Miniature Disposable Infusion IPMC Micropumps 199
9.3.1 Configuration of the IPMC Infusion Pump 200
9.3.2 The Control System 202
9.3.3 Performance Testing 203
9.4 Modelling for IPMC Micropumps 203
9.4.1 Equivalent Bimorph Beam Model for IPMC Actuators 203
9.4.2 IPMC Diaphragm 204
9.5 Conclusions 211
References 211
SECTION III CONJUGATED POLYMERS 215
10 Conjugated Polymer Actuators: Fundamentals 217
10.1 Introduction 217
10.2 Molecular Mechanisms of Actuation in ICPs 219
10.3 Comparison of Actuation Performance in Various ICPs 222
10.4 Electrochemistry of ICPs 223
10.5 Effect of Composition, Geometry and Electrolyte on Actuation of PPy 226
10.5.1 Effect of the Dopant Ion 226
10.5.2 Effect of Solvent 228
10.5.3 Charge Transfer Processes 230
10.5.4 Effect of Porosity/Morphology 234
10.6 Mechanical System Response 234
10.7 Device Design and Optimization 239
10.7.1 How to Tailor Actuator Performance to Meet Design Requirements 239
10.7.2 Design of a Swimming Device 241
10.7.3 Device Testing 243
10.8 Future Prospects 244
References 245
11 Steerable Catheters 251
11.1 Introduction 251
11.2 Catheters: History and Current Applications 251
11.3 Catheter Design Challenges 253
11.3.1 Biocompatibility 253
11.3.2 Small Size 254
11.3.3 Low Cost 254
11.3.4 Structural Rigidity 254
11.4 Active Steerable Catheters 256
11.4.1 Non-EAP Based Steerable Catheters 256
11.4.2 EAP Based Steerable Catheters 257
11.4.3 Conjugated Polymer Based Steerable Catheters 259
11.5 Discussion and Conclusion 268
References 268
12 Microfabricated Conjugated Polymer Actuators for Microvalves, Cell Biology, and Microrobotics 271
12.1 Introduction 271
12.2 Actuator Background 272
12.3 Microfabrication 273
12.4 Single Hinge Bilayer Devices: Flaps and Lids 275
12.4.1 Bilayer Actuators 276
12.4.2 Drug Delivery 276
12.4.3 Cell Manipulation 277
12.4.4 Cell-Based Sensors 278
12.5 Multi-Bilayer Devices: Positioning Tools 279
12.5.1 Microtools 279
12.5.2 Microrobot 279
12.6 Swelling Film Devices: Valves 280
12.6.1 Out-of-Plane Actuation Strain 281
12.6.2 Microvalve 281
12.7 Lifetime 282
12.8 Integrated Systems 282
12.9 Conclusions 283
References 283
13 Actuated Pins for Braille Displays 287
13.1 Introduction 287
13.2 Requirements for the Electronic Braille Screen 288
13.3 Mechanical Analysis of Actuators Operating Against Springs 290
13.4 Polypyrrole Actuators for Electronic Braille Pins 293
13.5 Other Polymer Actuation Systems for Electronic Braille Pins 296
13.6 Summary 297
Acknowledgements 298
References 298
14 Nanostructured Conducting Polymer Biomaterials and Their Applications in Controlled Drug Delivery 301
14.1 Introduction 301
14.2 Nanostructured Conducting Polymers 302
14.2.1 Fabrication 302
14.2.2 Biomedical Application 304
14.3 Conducting Polymer Nanotubes for Controlled Drug Delivery 307
14.3.1 Electrospinning 308
14.3.2 Electrospinning of Dexamethasone-Loaded Template PLGA Nanofibers 309
14.3.3 Electrochemical Deposition of PEDOT Nanotubes 310
14.3.4 Controlled Drug Delivery from PEDOT Nanotubes 311
14.4 Conclusions 315
Acknowledgements 315
References 315
15 Integrated Oral Drug Delivery System with Valve Based on Polypyrrole 323
15.1 Introduction 323
15.2 System Concept 325
15.3 Osmotic Pressure Pump 327
15.3.1 Valve Closed 327
15.3.2 Valve Open 328
15.4 Polypyrrole in Actuator Applications 329
15.4.1 Why PPy in the IntelliDrug System 329
15.4.2 Actuation of PPy 330
15.5 Valve Concepts Evaluated in the Course of the IntelliDrug Project 332
15.5.1 Wafer-Level Fabricated Membrane Valve 332
15.5.2 Micro-Assembled Membrane Valve 333
15.6 Total Assembly and Clinical Testing of the IntelliDrug System 336
Acknowledgement 337
References 338
SECTION IV PIEZOELECTRIC AND ELECTROSTRICTIVE POLYMERS 339
16 Piezoelectric and Electrostrictive Polymer Actuators: Fundamentals 341
16.1 Introduction 341
16.2 Fundamentals of Electromechanical Materials 342
16.2.1 Piezoelectric Effect 342
16.2.2 Electrostrictive Effect 343
16.2.3 Other Effects 345
16.3 Material Properties Related to Electromechanical Applications 346
16.3.1 Electromechanical Coupling Factor (k) 347
16.3.2 Elastic Response 348
16.3.3 Frequency and Temperature Responses 348
16.4 Typical Electromechanical Polymers and Their Properties 350
16.4.1 Piezoelectric Polymers 350
16.4.2 Electrostrictive Polymers 352
16.4.3 Maxwell Stress Effect Based Polymers 354
16.4.4 Practical Considerations 354
16.5 Conclusions 354
References 354
17 Miniature High Frequency Focused Ultrasonic Transducers for Minimally Invasive Imaging Procedures 357
17.1 Introduction 357
17.2 Coronary Imaging Needs 359
17.2.1 Vulnerable Plaques 359
17.2.2 Stent Thrombosis 361
17.3 High Resolution Ultrasonic Transducers 362
17.3.1 Polymer Transducers 363
17.4 Fabrication Techniques 364
17.5 Testing Methods 367
17.6 Results 368
17.7 Conclusion 373
References 373
18 Catheters for Thrombosis Sample Exfoliation in Blood Vessels Using Piezoelectric Polymer Fibers 379
18.1 Introduction 379
18.2 Piezoelectricity of Polymer Film and Fiber 380
18.3 Simple Measurement Method for the Bending Motion of Piezoelectric Polymer Fiber 383
18.4 Piezoelectric Motion of Poly-L-Lactic Acid (PLLA) Fiber 384
18.5 Elementary Demonstration of Prototype System for Catheters Using Piezoelectric Polymer Fiber 385
18.5.1 Preliminary Demonstration 386
18.5.2 More Realistic Model for Application of Piezoelectric Polymer Fiber to Catheter 386
18.6 Summary 389
References 389
19 Piezoelectric Poly(Vinylidene) Fluoride (PVDF) in Biomedical Ultrasound Exposimetry 391
19.1 Introduction 391
19.2 Needle Hydrophone Design 392
19.3 Spot Poled Membrane Hydrophone Design 393
19.4 Application to Diagnostic Ultrasound 394
19.5 Application to Therapeutic Ultrasound 396
19.6 Conclusion 399
References 400
SECTION V DIELECTRIC ELASTOMERS 407
20 Dielectric Elastomer Actuators: Fundamentals 409
20.1 Introduction 409
20.2 Basic Principle of Operation 410
20.3 Dielectric Elastomer Materials 411
20.4 Transducer Designs and Configurations 413
20.5 Operational Considerations 414
References 415
21 Biomedical Applications of Dielectric Elastomer Actuators 417
21.1 Introduction 417
21.2 UMA Based Actuators and Their Application to Pumps 418
21.3 Mechanical Stimulation Using Thickness-Mode Actuation 422
21.4 Implantable Artificial Diaphragm Muscle 425
21.5 Implantable Artificial Facial Muscles 427
21.6 Limb Prosthetics and Orthotics 428
21.7 Mechanical Actuation for ‘Active’ Cell Culture Assays 430
21.8 Conclusions 431
References 432
22 MRI Compatible Device for Robotic Assisted Interventions to Prostate Cancer 433
22.1 Introduction 433
22.2 Prostate Cancer Therapy 435
22.2.1 Prostate Cancer Detection 435
22.2.2 Prostate Cancer Treatment 436
22.2.3 Needle Placement in MRI Systems 437
22.3 Elastically Averaged Parallel Manipulator Using Dielectric Elastomer Actuators 437
22.3.1 Design Requirements 437
22.3.2 Manipulator Concept 439
22.3.3 Manipulator Analytical Model 440
22.4 Results 442
22.4.1 Analytical Results 443
22.4.2 Experimental Results 445
22.5 Conclusions 446
Acknowledgements 446
References 446
23 A Braille Display System for the Visually Disabled Using a Polymer Based Soft Actuator 449
23.1 Introduction 449
23.2 Fundamentals of Actuation Principle 450
23.3 Design of Tactile Display Device 452
23.4 Braille Display System 453
23.4.1 Fabrication 453
23.4.2 System Outline 454
23.4.3 Experiments 456
23.5 Advanced Applications 459
23.5.1 Wearable Tactile Display System 459
23.5.2 Virtual Reality Tactile Display 462
23.6 Conclusions 463
References 463
24 Dynamic Splint-Like Hand Orthosis for Finger Rehabilitation 465
24.1 Introduction 465
24.2 Passive Dynamic Hand Splints: State of the Art 466
24.3 Active Dynamic Hand Splints: State of the Art 467
24.4 Proposed Concept: Dynamic Splint Equipped with Dielectric Elastomer Actuators 468
24.5 Splint Mechanics 471
24.6 Dimensioning of the Actuators 471
24.7 Prototype Splint 472
24.8 Performance of the Prototype Splint 473
24.9 Future Developments 476
24.9.1 Magnetic Resonance Imaging-Compatible Hand Splint 476
24.9.2 Electromyography-Controlled Hand Splint 479
24.10 Conclusions 482
References 482
Index 485
Plates 499

Produkt-Details

• Erscheint lt. Verlag: 13.4.2009
• Sprache: englisch
• Themenwelt: Medizin / Pharmazie ► Allgemeines / Lexika
• Themenwelt: Naturwissenschaften ► Chemie ► Organische Chemie
• Themenwelt: Technik ► Elektrotechnik / Energietechnik
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: Electrical & Electronics Engineering • Electronic materials • Elektronische Materialien • Elektrotechnik u. Elektronik • Materials Science • Materialwissenschaften • Polymer Science & Technology • Polymerwissenschaft u. -technologie
• ISBN-10: 0-470-74468-5 / 0470744685
• ISBN-13: 978-0-470-74468-0 / 9780470744680