1;Preface;5 2;Authors Brief Biography;8 3;Foreword;10 4;Contents;11 5;1 Introduction;14 5.1;1.1 Definition and Application of Hydrogel;14 5.2;1.2 Historical Development of Modelling Hydrogel;16 5.2.1;1.2.1 Steady-State Modelling for Equilibrium of Smart Hydrogels;17 5.2.1.1;1.2.1.1 Mathematical Models and Simulations;18 5.2.1.2;1.2.1.2 Key Parameters in Steady-State Modelling for Equilibrium of Hydrogels;33 5.2.2;1.2.2 Transient Modelling for Kinetics of Smart Hydrogels;42 5.2.2.1;1.2.2.1 Mathematical Models and Simulations;44 5.2.2.2;1.2.2.2 Key Parameters in Transient Modelling for Kinetics of Hydrogels;50 5.2.3;1.2.3 A Theoretical Formalism for Diffusion Coupled with Large Deformation of Hydrogel;56 5.2.4;1.2.4 Remarks;58 5.3;1.3 About This Monograph;58 5.4;References;60 6;2 Multi-Effect-Coupling pH-Stimulus (MECpH) Model for pH-Sensitive Hydrogel;69 6.1;2.1 Introduction;69 6.2;2.2 Development of the MECpH Model;69 6.2.1;2.2.1 Electrochemical Formulation;70 6.2.1.1;2.2.1.1 Ionic Flux;71 6.2.1.2;2.2.1.2 Electrical Potential;73 6.2.1.3;2.2.1.3 Fixed Charge Group;77 6.2.2;2.2.2 Mechanical Formulation;79 6.3;2.3 Computational Domain, Boundary Condition and Numerical Implementation;83 6.4;2.4 Model Validation with Experiment;88 6.5;2.5 Parameter Studies by Steady-State Simulation for Equilibrium of Hydrogel;90 6.5.1;2.5.1 Influence of Initially Fixed Charge Density of Hydrogel;93 6.5.2;2.5.2 Influence of Young's Modulus of Hydrogel;97 6.5.3;2.5.3 Influence of Initial Geometry of Hydrogel;103 6.5.4;2.5.4 Influence of Ionic Strength of Bath Solution;107 6.5.5;2.5.5 Influence of Multivalent Ionic Composition of Bath Solution;114 6.6;2.6 Remarks;120 6.7;References;123 7;3 Multi-Effect-Coupling Electric-Stimulus (MECe) Model for Electric-Sensitive Hydrogel;127 7.1;3.1 Introduction;127 7.2;3.2 Development of the MECe Model;127 7.2.1;3.2.1 Formulation of the MECe Governing Equations;128 7.2.2;3.2.2 Boundary and Initial Conditions;138 7.3;3.3 Steady-State Simulation for Equilibrium of Hydrogel;139 7.3.1;3.3.1 Numerical Implementation;139 7.3.2;3.3.2 Model Validation with Experiment;143 7.3.3;3.3.3 Parameter Studies;144 7.3.3.1;3.3.3.1 Influence of Externally Applied Electric Voltage;146 7.3.3.2;3.3.3.2 Influence of Initially Fixed Charge Density of Hydrogel;149 7.3.3.3;3.3.3.3 Influence of Concentration of Bath Solution;154 7.3.3.4;3.3.3.4 Influence of Ionic Valence of Bath Solution;156 7.4;3.4 Transient Simulation for Kinetics of Hydrogel;156 7.4.1;3.4.1 Numerical Implementation;159 7.4.2;3.4.2 Model Validation with Experiment;162 7.4.3;3.4.3 Parameter Studies;163 7.4.3.1;3.4.3.1 Variation of Ionic Concentration Distribution with Time;164 7.4.3.2;3.4.3.2 Variation of Electric Potential Distribution with Time;172 7.4.3.3;3.4.3.3 Variation of Hydrogel Displacement Distribution with Time;172 7.4.3.4;3.4.3.4 Variation of Hydrogel Average Curvature with Time;179 7.5;3.5 Remarks;182 7.6;References;183 8;4 Multi-Effect-Coupling pH-Electric-Stimuli (MECpHe) Model for Smart Hydrogel Responsive to pH-Electric Coupled Stimuli;185 8.1;4.1 Introduction;185 8.2;4.2 Development of the MECpHe Model;186 8.3;4.3 Numerical Implementation;192 8.4;4.4 Model Validation with Experiment;194 8.5;4.5 Parameter Studies by Steady-State Simulation for Equilibrium of Hydrogel;196 8.5.1;4.5.1 Influence of Solution pH Coupled with External Electric Voltage;196 8.5.2;4.5.2 Influence of Initially Fixed Charge Density of Hydrogel;203 8.5.3;4.5.3 Influence of Ionic Strength;211 8.5.4;4.5.4 Influence of Ionic Valence;221 8.6;4.6 Remarks;226 8.7;References;229 9;5 Multi-Effect-Coupling Thermal-Stimulus (MECtherm) Model for Temperature-Sensitive Hydrogel;231 9.1;5.1 Introduction;231 9.2;5.2 Development of the MECtherm Model;231 9.2.1;5.2.1 Free Energy;232 9.2.2;5.2.2 Poisson--Nernst--Planck Formulation;235 9.3;5.3 Numerical Implementation;235 9.4;5.4 Model Validation with Experiment;240 9.5;5.5 Parameter Studies by Steady-State Simulation for Thermo-Sensitive Ionized Hydrog