Multifunctional Hydrogels. From Basic Concepts to Advanced Applications

Cover
Half Title
Multifunctional Hydrogels: From Basic Concepts to Advanced Applications
Copyright
Contents
Preface
Editor Biographies
Contributors
1. Multifunctional Hydrogels: An Introduction
	1.1 Introduction
	1.2 Chemistry and Properties of Hydrogels
	1.3 Applications of Hydrogels
		1.3.1 Hydrogels for Energy Production
		1.3.2 Hydrogels for Energy Storage
		1.3.3 Hydrogels for Sensors
		1.3.4 Hydrogels for Biomedicals
	1.4 Conclusion
	References
2. Hydrogels Based on Natural and/or Synthetic Polymers
	2.1 Introduction
	2.2 Natural Hydrogels
		2.2.1 Cellulose and Starch
		2.2.2 Alginates
		2.2.3 Non-Vegetable Sources
			2.2.3.1 Chitin and Chitosan
			2.2.3.2 Collagen and Gelatin
			2.2.3.3 Silk Fibroin
			2.2.3.4 Fibrin
			2.2.3.5 Hyaluronic Acid
	2.3 Synthetic Hydrogels
		2.3.1 Polyesters and Polyamides
		2.3.2 Polyacrylates and Polymethacrylates
		2.3.3 Polymer Amines
		2.3.4 Polyvinyl Alcohol Hydrogels
	2.4 Conclusions
	Acknowledgments
	References
3. Nanocomposite Hydrogels
	3.1 Introduction
	3.2 Synthesis of Nanocomposite Hydrogels
		3.2.1 Carbon Nanostructure-Based Nanocomposite Hydrogels
		3.2.2 Polymeric Nanoparticle-Based Nanocomposite Hydrogels
		3.2.3 Metal Nanoparticle-Based Nanocomposite Hydrogels
		3.2.4 Inorganic Nanoparticle-Based Nanocomposite Hydrogels
	3.3 Natural Polymer-Based Nanocomposite Hydrogels
		3.3.1 Polysaccharide-Based Nanocomposite Hydrogels
		3.3.2 DNA-Based Nanocomposite Hydrogels
		3.3.3 Protein Nanocomposite Hydrogels
	3.4 Properties of Nanocomposite Hydrogels
		3.4.1 Stimuli Response
		3.4.2 Mechanical Properties
		3.4.3 Electrical Properties
		3.4.4 Magnetic Properties
		3.4.5 Thermal Properties
		3.4.6 Swelling Properties
	3.5 Conclusion and Future Trends
	References
4. Synthesis of Hydrogels: Physical and Chemical Cross-Linking
	4.1 Introduction
	4.2 Cross-Linking
	4.3 Chemical Cross-Linking
		4.3.1 Chain Growth Polymerization or Addition Polymerization
			4.3.1.1 Condensation Polymerization or Step-Growth Polymerization
		4.3.2 Radiation Cross-Linking
			4.3.2.1 Photo-Cross-Linking Radiation
		4.3.3 Graft Copolymerization
		4.3.4 Free-Radical Polymerization
			4.3.4.1 Photo-Cross-Linking Radiation
			4.3.4.2 Graft Copolymerization
		4.3.5 Free-Radical Polymerization
		4.3.6 Interpenetrating Networks
	4.4 Physical Cross-Linking
		4.4.1 Crystallization (Freeze/Thaw Cycles)
		4.4.2 Hydrophobic Interactions
		4.4.3 Amphiphilic Copolymers
		4.4.4 Charge Interactions
		4.4.5 Interactions by Hydrogen Bonds
		4.4.6 Stereocomplex Formation
		4.4.7 Protein Interactions
	4.5 Conclusion
	References
5. Fabrication Techniques of Hydrogels
	5.1 Introduction
	5.2 Fabrication Techniques of Hydrogels
	5.3 Electrospinning
		5.3.1 Solution Electrospinning
		5.3.2 Melt Electrospinning
		5.3.3 Electrospinning Parameters
	5.4 Gas Foaming
	5.5 Sol-Gel Method
	5.6 Three-Dimensional Printing
		5.6.1 Laser Printing
		5.6.2 Stereolithography
		5.6.3 Two-Photon Polymerization
		5.6.4 Laser-Induce Forward Transfer
		5.6.5 Inkjet Printing
		5.6.6 Extrusion Printing
	5.7 Melt Molding
		5.7.1 Freeze-Drying
	5.8 Other Methodologies
		5.8.1 Grafting
			5.8.1.1 Plasma Treatment
		5.8.2 High-Energy Electron Beam Irradiation
		5.8.3 Hydrogel Nanocomposites Formation
			5.8.3.1 Blending Method
			5.8.3.2 In Situ Method
	5.9 Conclusion
	References
6. Hydrogel-Based Sensors with Advanced Properties
	6.1 Introduction
	6.2 Hydrogels with Self-Healing Properties
	6.3 Hydrogels with Shape Memory Properties
	6.4 Hydrogels with Hydrophobic and Superhydrophobic Properties
	6.5 Hydrogels with Conductive Properties
	6.6 Hydrogels with Magnetic Properties
	6.7 Future Trends on Hydrogels with Advanced Properties
	6.8 Conclusions
	Acknowledgments
	References
7. Chemical-Responsive Reversible Hydrogels
	7.1 Introduction
	7.2 Chemically Responsive Hydrogels
		7.2.1 pH-Responsive Hydrogels
		7.2.2 Ion-Responsive Hydrogels
		7.2.3 Chemical- and Biochemical-Responsive Hydrogels
		7.2.4 Molecular Recognition
	7.3 Functionality and Applications
	7.4 Conclusion and Outlook
	References
8. Hydrogels with Electrical Properties
	8.1 Introduction
	8.2 Ion-Conducting Hydrogels
	8.3 Electronically Conducting Hydrogels
	8.4 Semi-Interpenetrated Conducting Hydrogels
	8.5 Metallic Nanomaterials
	8.6 Carbon Nanomaterials
	8.7 Other Conducting Nanomaterials: Mxenes and Conducting Polymers
	8.8 Conclusions
	References
9. Hydrogels with Magnetic Properties
	9.1 Introduction
	9.2 Preparation of Magnetic Hydrogels
		9.2.1 In situ Synthesis
		9.2.2 Ex situ Synthesis
	9.3 The Future of Magnetic Nanomaterials
	9.4 Recent Advances of Magnetic Hydrogels
		9.4.1 Cancer Theranostics
		9.4.2 Diabetes
		9.4.3 Wearable Devices
		9.4.4 Soft Robotics
		9.4.5 Gas Detection System
	9.5 Challenges and Future Prospects
	9.6 Concluding Remarks
	References
10. Hydrogels with Thermal Responsiveness
	10.1 Introduction
	10.2 Thermoresponsive Behavior in Polymers
		10.2.1 Hydrogels with VPTT Based on LCST
		10.2.2 Hydrogels with VPTT Based on UCST
		10.2.3 Hydrogels with VPTT Based on Both LCST and UCST Behavior
	10.3 Dual Thermo- and pH-Responsive Hydrogels
	10.4 Thermosensitive Nanocomposite Hydrogels
		10.4.1 Natural Thermosensitive Polymeric Matrixes for Nanocomposite Hydrogels
		10.4.2 Synthetic Thermosensitive Polymeric Matrixes for Nanocomposite Hydrogels
	10.5 Thermo- and Dual-Responsive Hydrogels with Nanomaterials as Fillers
		10.5.1 Thermo- and pH-Responsive Hydrogels
		10.5.2 Thermo- and Light-responsive Hydrogels
		10.5.3 Thermo- and Electrical Responsive Hydrogels
		10.5.4 Thermo- and Magnetic-Responsive Hydrogels
	10.6 Dual-Responsive Temperature-Sensitive Hydrogels for Specific Applications
	10.7 Conclusions and Future Perspectives
	References
11. Mechanical Properties of Multifunctional Hydrogels
	11.1 Introduction to Mechanical Properties of Multifunctional Hydrogels
	11.2 Mechanical Modeling of Hydrogels
		11.2.1 Rubber-like Elasticity
		11.2.2 Viscoelasticity
		11.2.3 Equilibrium Swelling Theory
	11.3 Experimental Methods for Mechanical Characteristics
		11.3.1 Stress-Strain Tests
		11.3.2 Creep and Stress Relaxation
		11.3.3 Cyclic deformation
		11.3.4 Fracture Processes
		11.3.5 Dynamic Mechanical Analysis
			11.3.5.1 Amplitude Sweep
			11.3.5.2 Frequency Sweep
			11.3.5.3 Temperature Sweep
			11.3.5.4 Time Sweep
	11.4 Tuning and Control of the Mechanical Properties of Multifunctional Hydrogels
		11.4.1 Multifunctional Hydrogel Network Types
		11.4.2 The Effect of Gel Network Compositions and Swelling Behavior on Mechanical Properties
			11.4.2.1 The Effect of Swelling on the Mechanical Behavior of Hydrogels
			11.4.2.2 The Effect of Monomer Concentration and Composition on the Mechanical Behavior of Hydrogels
			11.4.2.3 The Effect of Cross-linker Density and Type on the Mechanical Behavior of Hydrogels
			11.4.2.4 The Effect of Cross-linking Temperature on the Mechanical Behavior of Hydrogels
			11.4.2.5 The Effect of Polymer Type and Content on the Mechanical Behavior of Hydrogels
		11.4.3 Design of Composite Hydrogels for Enhancing Mechanical Properties
		11.4.4 Mechanoresponsive Hydrogels with Different Biomedical Applications
			11.4.4.1 Strain-Stiffening of Hydrogels
			11.4.4.2 Shear-Thinning and Self-Healing of Hydrogels
			11.4.4.3 Mechanochromic Hydrogels
	11.5 Conclusion
	References
12. Hydrogels for Bioelectronics
	12.1 Introduction
	12.2 Conductivity in Hydrogels
		12.2.1 Ionic Conductivity: Polyelectrolytes and Salts
		12.2.2 Electronic Conductivity: Metal/Carbon Nanostructures
		12.2.3 Electronic Conductivity: Conducting Polymers
		12.2.4 Hybrid Conductivity
	12.3 Hydrogel Materials for Bioelectronic Applications
		12.3.1 Natural Hydrogels
			12.3.1.1 Gelatin
			12.3.1.2 Chitosan
			12.3.1.3 Cellulose
			12.3.1.4 Alginate
		12.3.2 Synthetic Hydrogels
			12.3.2.1 Polyacrylamide (PAAm)
			12.3.2.2 Polyvinyl Alcohol (PVA)
			12.3.2.3 Polyethylene Glycol (PEG)
	12.4 Applications of Hydrogels in Bioelectronics: Sensing, Diagnostic, and Therapeutics
		12.4.1 On-Skin Bioelectronics
			12.4.1.1 Epidermal Bioelectronics
			12.4.1.2 Wound Patch Devices
			12.4.1.3 Biochemical Sensor
		12.4.2 Implantable Devices and Tissue Engineering
			12.4.2.1 Neurological Signal Monitoring
			12.4.2.2 Tissue Engineering
	12.5 Conclusions
	References
13. Hydrogels for Physical and (Bio)Chemical Sensors
	13.1 An Introduction to Designing Sensors and Biosensors
		13.1.1 Sensors: Definition and Classification
		13.1.2 Biosensors
		13.1.3 Hydrogel-Based Sensors
		13.1.4 Polymer Hydrogel-Based (Bio)Sensors
		13.1.5 Design and Principal
	13.2 Immobilization Techniques for Functionalization of Hydrogels
		13.2.1 Physical or Reversible Immobilization
		13.2.2 Chemical or Irreversible Immobilization
	13.3 Transducing Strategies
		13.3.1 Electrochemical Sensors
		13.3.2 Optical
		13.3.3 Microelectromechanical Systems
		13.3.4 Stimuli-Responsive Sensors
	13.4 Conclusion and Perspectives
	References
14. Hydrogels for Biomedical Applications
	14.1 Hydrogels for Biomedical and Technological Applications
	14.2 Biocompatibility of Hydrogels in Cellular Systems
		14.2.1 Purification and Sterilization of Hydrogels
		14.2.2 Seeding of Cell Cultures on Hydrogels Surfaces
		14.2.3 Isolating Cells from Hydrogels
		14.2.4 Cell and Nuclear Morphology Analysis after Contacting Hydrogels
		14.2.5 Cell Viability/Cytotoxicity Assays
		14.2.6 Intra- and Extracellular Parameters Determination
	14.3 Cell/Hydrogel Biointerface
		14.3.1 Biointerfacial Wettability and Chemical Composition of the Scaffold
	14.4 In Vivo Assessment of Hydrogels\' Biocompatibility
	14.5 Applications
		14.5.1 Nanomedicine Applications
		14.5.2 Mammalian Sperm Selection by Attachment to Hydrogel Surfaces
	14.6 Conclusions
	Notes
15. Hydrogels for Drug Delivery
	15.1 Introduction
	15.2 Classification of Hydrogels
		15.2.1 Macroscopic Hydrogels
		15.2.2 In Situ Injectable Hydrogels
		15.2.3 Shear Thinning Hydrogels
		15.2.4 Microgels and Nanogels
	15.3 Mechanism of Gelation
		15.3.1 Chemical Hydrogels
			15.3.1.1 Biorthogonal Chemical Reactions
			15.3.1.2 Non-Biorthogonal Reaction
		15.3.2 Physical Hydrogels
			15.3.2.1 Physical Hydrogels Based on Hydrogen Bonding
			15.3.2.2 Physical Hydrogels Based on Hydrophobic Interaction
			15.3.2.3 Physical Hydrogels based on Ionic Bonds
	15.4 Pharmaceutical Stimuli-Responsive Hydrogels
		15.4.1 Injectable pH-Responsive Hydrogels
		15.4.2 Temperature-Responsive Hydrogels
		15.4.3 Photon-Responsive Hydrogels
		15.4.4 Enzyme-Responsive Hydrogels
		15.4.5 Electro-Responsive Hydrogels
	15.5 Regulation on Hydrogels
		15.5.1 Drug Products
		15.5.2 Barriers on Clinical Translation
	15.6 Conclusion and Future Perspectives
	References
16. Hydrogels for Anti-Pathogen Applications
	16.1 Introduction
	16.2 Hydrogels for Anti-Bacterial Therapy
	16.3 Hydrogels for Anti-Fungal Therapy
	16.4 Hydrogels for Anti-Viral Therapy
		16.4.1 Therapy against Viral Infection
		16.4.2 Perspective for Hydrogels against COVID-19 and Other Coronaviruses
	16.5 Hydrogels for Anti-Parasitic Therapy
	16.6 Conclusions and Outlook
	Acknowledgments
	References
17. Hydrogels for Environmental Applications
	17.1 Introduction
	17.2 Preparative Methods of Hydrogels to be used for Environmental Applications
	17.3 Properties of Hydrogels to be used for Environmental Applications
	17.4 Various Environmental Applications
		17.4.1 Agricultural Applications
			17.4.1.1 Soil Conditioner
			17.4.1.2 Slow-Release Fertilizer
			17.4.1.3 Soilless Cultivation
		17.4.2 Enhanced Oil Recovery
		17.4.3 Food Packaging
		17.4.4 Health and Safety
		17.4.5 Sensor
		17.4.6 Water Remediation
			17.4.6.1 Metal Ion Removal
			17.4.6.2 Dye Removal
			17.4.6.3 Pharmaceutical Removal
			17.4.6.4 Pesticide Removal
		17.4.7 Oil-Water Separation
	17.5 Conclusion
	References
18. Hydrogels for Wastewater Cleaning and Water Recovery
	18.1 Introduction
	18.2 Hydrogel Materials Applied for Wastewater Treatment and Water Purification
	18.3 Hydrogels in Oil/Water Separation
	18.4 Hydrogels in Wastewater Treatments
		18.4.1 Hydrogels in the Adsorptive Removal of Pollutants
		18.4.2 Hydrogels for Advanced Oxidation Process (AOPs) in Wastewater Treatments
		18.4.3 Hydrogels in Biological Processes of Wastewater Treatments
	18.5 Hydrogels in Water Purification
		18.5.1 Solar Water Purification
		18.5.2 Reverse Osmosis
		18.5.3 Forward Osmosis
		18.5.4 Electrodialysis
		18.5.5 Capacitive Deionization
	18.6 Future of Hydrogels in Freshwater Production and Wastewater Purification
	Acknowledgments
	References
19. Hydrogels for Soft Robotics
	19.1 Introduction
	19.2 Fundamentals of Hydrogels
	19.3 Hydrogel-Based Components of Soft Robotics
		19.3.1 Hydrogel-Based Actuators
	19.4 Morphing of Hydrogel-Based Structure for Soft Robotics
		19.4.1 Folding and Bending
		19.4.2 Micro and Meso Patterning
		19.4.3 Anisotropy using Additives and Alignment
		19.4.4 Gradients
	19.5 Conclusion
	References
Index