Hydrogel Micro and Nanoparticles

The book provides experienced as well as young researchers with a topical view of the vibrant field of soft nanotechnology. In addition to elucidating the underlying concepts and principles that drive continued innovation, major parts of each chapter are devoted to detailed discussions of potential and already realized applications of micro– and nanogel– based materials. Examples of the diverse areas impacted by these materials are biocompatible coatings for implants, films for controlled drug release, self–healing soft materials and responsive hydrogels that react to varying pH conditions, temperature or light.

List of Contributors XIII Foreword XIX Preface XXIII 1 Thermally Sensitive Microgels: From Basic Science to Applications 1 He Cheng and Guangzhao Zhang 1.1 Introduction 1 1.2 Theoretical Background 2 1.3 Basic Physics of Microgels 7 1.4 Applications 25 1.5 Conclusions 27 References 29 2 Thermosensitive Core – Shell Microgels: Basic Concepts and Applications 33 Yan Lu and Matthias Ballauff 2.1 Introduction 33 2.2 Volume Transition in Single Particles 35 2.3 Concentrated Suspensions: 3D Crystallization 40 2.4 Particles on Surfaces: 2D Crystallization 41 2.5 Concentrated Suspensions: Rheology 42 2.6 Core–Shell Particles as Carriers for Catalysts 45 2.7 Conclusion 53 References 54 3 Core – Shell Particles with a Temperature–Sensitive Shell 63 Haruma Kawaguchi 3.1 Introduction 63 3.2 Preparation of Core–Shell Particles with a Temperature–Sensitive Shell 63 3.4 Properties, Functions and Applications of Core–Shell Particles with a Temperature–Sensitive Shell 75 3.5 Conclusions 78 References 79 4 pH–Responsive Nanogels: Synthesis and Physical Properties 81 Beng Hoon Tan, Jeremy Pang Kern Tan, and Kam Chiu Tam 4.1 Introduction 81 4.2 Preparation Techniques for pH–Responsive Nanogels 82 4.3 Structural Properties of pH–Responsive Nanogels 85 4.4 Swelling of pH–Responsive Nanogels 87 4.5 Rheological Behavior of pH–Responsive Nanogels 96 4.6 Approach to Model pH–Responsive Nanogel Properties 97 4.7 Osmotic Compressibility of pH–Responsive Nanogels in Colloidal Suspensions 106 4.8 Conclusions and Future Perspectives 109 References 110 5 Poly( N –Vinylcaprolactam) Nano– and Microgels 117 Cheng Cheng and Andrij Pich 5.1 Introduction 117 5.2 Poly(N–Vinylcaprolactam): Synthesis, Structure and Properties in Solution 117 5.3 Thermal Behavior of Poly(N–Vinylcaprolactam) in Water 120 5.4 PVCL Nano– and Microgels 123 5.5 Conclusions 137 References 137 6 Doubly Crosslinked Microgels 141 Brian R. Saunders 6.1 Introduction 141 6.2 Methods of Preparation 145 6.3 Methods of Characterization 148 6.4 Morphology 155 6.5 Properties 157 6.6 Potential Applications 162 6.7 Conclusion 165 References 166 7 ATRP: A Versatile Tool Toward Uniformly Crosslinked Hydrogels with Controlled Architecture and Multifunctionality 169 Jeong Ae Yoon, Jung Kwon Oh, Wenwen Li, Tomasz Kowalewski, and Krzysztof Matyjaszewski 7.1 Incorporating Crosslinking Reactions into Controlled Radical Polymerization 169 7.2 Effect of Network Homogeneity on Thermoresponsive Hydrogel Performance 171 7.3 Gel Networks Containing Functionalized Nanopores 176 7.4 Toward Micro– and Nano–Sized Hydrogels by ATRP 180 References 184 8 Nanogel Engineering by Associating Polymers for Biomedical Applications 187 Yoshihiro Sasaki and Kazunari Akiyoshi 8.1 Introduction 187 8.2 Preparation of Associating Polymer–Based Nanogels 188 8.3 Functions of Self–Assembled Nanogels 194 8.4 Application of Polysaccharide Nanogels to DDS 197 8.5 Integration of Nanogels 199 8.6 Conclusion and Perspectives 202 References 202 9 Microgels and Biological Interactions 209 Michael H. Smith, Antoinette B. South, and L. Andrew Lyon 9.1 An Introduction to Polymer Biomaterials 209 9.2 Drug Delivery 213 9.3 Biomaterial Films 221 9.4 Conclusion 228 References 229 10 Oscillating Microgels Driven by Chemical Reactions 237 Daisuke Suzuki 10.1 Introduction 237 10.2 Types of Oscillating Microgels 238 10.3 Synthesis and Fabrication of Oscillating Microgels 240 10.4 Control of Oscillatory Behavior 241 10.5 Flocculating/Dispersing Oscillation 251 10.6 Concluding Remarks 254 References 254 11 Smart Microgel/Nanoparticle Hybrids with Tunable Optical Properties 257 Matthias Karg and Thomas Hellweg 11.1 Introduction 257 11.2 Synthesis of Hybrid Gels 258 11.3 Characterization of Hybrid Gels 260 11.4 Hybrid Microgels with Plasmon Properties 261 11.5 Photoluminescent Hybrid Microgels 269 11.6 Summary 272 References 274 12 Macroscopic Microgel Networks 281 Todd Hoare 12.1 Introduction and Motivation 281 12.2 Preparation of Microgel Networks 284 12.3 Applications of Microgel Networks 301 12.4 Conclusions and Future Outlook 310 References 311 13 Color–Tunable Poly ( N –Isopropylacrylamide) Microgel–Based Etalons: Fabrication, Characterization, and Applications 317 Michael J. Serpe, Courtney D. Sorrell, Matthew C.D. Carter, Ian N. Heppner, Janelle B. Smiley–Wiens, and Liang Hu 13.1 Introduction 317 13.2 Microgel–Based Photonic Materials 319 13.3 Conclusions and Future Directions 330 References 332 14 Crystals of Microgel Particles 337 Juan José Liétor–Santos, Urs Gasser, Jun Zhou, Zhibing Hu, and Alberto Fernández–Nieves 14.1 Introduction 337 14.2 Theoretical Background and Experimental Methods 339 14.3 Determining and Modeling the Particle Form Factor 353 14.4 Structure Factor of Concentrated Suspensions 357 14.5 Final Remarks and Future Directions 365 References 366 15 Dynamical Arrest and Crystallization in Dense Microgel Suspensions 369 Priti Mohanty, Divya Paloli, Jerome Crassous, and Peter Schurtenberger 15.1 Introduction 369 15.2 Methods 372 15.3 Synthesis and Responsive Properties 374 15.4 Structural and Dynamic Properties of Neutral Microgels 379 15.5 Structural and Dynamic Properties of Soft and Weakly Charged Microgels 388 15.6 Conclusions and Outlook: Probing Anisotropic Interactions 391 References 394 Index 397

L. Andrew Lyon is Professor in the School of Chemistry and Biochemistry at the Georgia Institute of Technology, Atlanta, USA. After his PhD in Physical Chemistry from Northwestern University he joined Penn State University as a postdoctoral research associate before pursuing his academic career at the Georgia Institute of Technology. Professor Lyon has authored more than 100 articles, contributed to nine books and holds seven patents. His research interests center around the development and implementation of new materials, particularly hydrogel nanoparticles, for photonics, bioanalysis, and biomimetics. Michael J. Serpe is Professor in the Department of Chemistry at the University of Alberta, Canada. He did his PhD in Analytical Chemistry at the Georgia Institute of Technology and then held positions as postdoctoral fellow at the University of Melbourne, Australia, at World Precision Instruments, Inc., and at the Duke University, USA. Professor Serpe has published more than 25 articles for one of which he received an outstanding research paper award. His group is interested in studying the behavior and fundamental properties of soft, responsive, functional, polymeric materials.