1;Preface;6 2;Contents;8 3;About the Editors;10 4; Lignin as Potent Industrial Biopolymer: An Introduction;12 4.1;1 Introduction;13 4.2;2 Sources and Structure of Lignin;13 4.2.1;2.1 Major Sources of Lignin;13 4.2.2;2.2 Structural Composition of Lignin;15 4.3;3 Lignin Extraction from Different Types of Biomass;16 4.3.1;3.1 Biological or Enzymatic Methods;16 4.3.2;3.2 Chemical Methods;17 4.3.3;3.3 Physical Methods;17 4.3.4;3.4 Miscellaneous Processes of Lignin Extraction and Conversion;18 4.4;4 Challenges in Lignin Conversion;18 4.5;5 Lignin-Derived Products of Industrial Importance;19 4.5.1;5.1 Lignin-Based Foams;19 4.5.2;5.2 Epoxy Resins from Lignins;20 4.5.3;5.3 Lignin-Based Ethers;20 4.5.4;5.4 Lignin-Based Esters;20 4.5.5;5.5 Lignin-Based Paints and Coatings;21 4.6;6 Conclusion;21 4.7;References;22 5; Structure and Characteristics of Lignin;27 5.1;1 Introduction;28 5.2;2 Structural Features of Lignin;31 5.2.1;2.1 Monolignols/Units;31 5.2.2;2.2 Inter-Unit Linkages;34 5.2.3;2.3 Lignin-Carbohydrate Complex (LCC);37 5.2.4;2.4 Monolignol Radicals;38 5.2.5;2.5 Biosynthesis of Lignin;39 5.2.6;2.6 Computational Assays;42 5.2.7;2.7 Structural Models of Lignin;43 5.2.8;2.8 Classification of Lignins;45 5.3;3 Physicochemical Properties of Lignin;45 5.3.1;3.1 Heating Values;45 5.3.2;3.2 Molecular Weight and Polydispersity;45 5.3.3;3.3 Thermal Characterization;46 5.3.4;3.4 Solubility;47 5.3.5;3.5 Relative Density;48 5.3.6;3.6 Color;48 5.3.7;3.7 Functional Groups;48 5.3.8;3.8 Chemical Reactions;49 5.4;4 Depolymerization and Isolation Technologies;50 5.4.1;4.1 Brauns' Lignin;50 5.4.2;4.2 Milled Wood Lignin (MWL);51 5.4.3;4.3 Soda Lignin (Alkali Lignin);51 5.4.4;4.4 Kraft Lignin;52 5.4.5;4.5 Sulfite Lignin (Lignosulfonates);52 5.4.6;4.6 Organosolv Lignin;53 5.4.7;4.7 Klason Lignin;53 5.4.8;4.8 Hydrolytic Lignin;53 5.4.9;4.9 Acidolysis Lignin;54 5.4.10;4.10 Cellulolytic Enzyme Lignin (CEL);54 5.4.11;4.11 Enzymatic Mild Acidolysis Lignin (EMAL);54 5.4.12;4.12 Pyrolytic Lignin;55 5.4.13;4.13 Steam Explosion Lignin (SEL);55 5.4.14;4.14 Ionic Liquid Extraction;55 5.4.15;4.15 Derivatization Followed by Reductive Cleavage (DFRC);56 5.5;5 Instrumental Strategies;56 5.5.1;5.1 Elemental Analysis;57 5.5.2;5.2 Spectroscopic Methods;57 5.6;6 Summary and Prospects;69 5.7;References;71 6; Lignin Synthesis and Degradation;86 6.1;1 Introduction;86 6.2;2 Lignin Biosynthesis;88 6.2.1;2.1 Synthesis of Lignin Monomeric Units;88 6.2.2;2.2 Glycosylation of Monolignols Their Storage and Transport;94 6.2.3;2.3 Oxidative Polymerization;95 6.3;3 Lignin Degradation;95 6.3.1;3.1 Lignin-Modifying Enzymes;98 6.3.2;3.2 Supplementary Enzymes for Lignin Degradation (LDEs);104 6.4;4 Way Forward;113 6.5;References;115 7; Analysis of Lignin Using Qualitative and Quantitative Methods;123 7.1;1 Introduction;123 7.1.1;1.1 Lignin;124 7.1.2;1.2 Biological Role and Commercial Significance;125 7.2;2 Lignin Analysis;127 7.2.1;2.1 Qualitative Methods of Lignin Analysis;128 7.2.2;2.2 Quantitative Methods of Lignin Analysis;133 7.2.3;2.3 Future Challenge and Development;140 7.3;3 Conclusion;141 7.4;References;142 8; Chemical Modification of Lignin by Polymerization and Depolymerization;147 8.1;1 Introduction;147 8.2;2 Lignin Polymerization;149 8.2.1;2.1 Methods for the Synthesis of New Reactive Sites in Lignin Structure;149 8.2.2;2.2 Modification of Lignin's Hydroxyl Groups;154 8.2.3;2.3 Lignin-Based Polymers;159 8.3;3 Lignin Depolymerization;164 8.3.1;3.1 Depolymerization by Chemical Treatment;166 8.3.2;3.2 Depolymerization by the Thermochemical Process;170 8.3.3;3.3 Depolymerization by Biological Transformations;176 8.4;4 Conclusions;178 8.5;References;179 9; Lignin and Its Composites;189 9.1;1 Introduction;189 9.2;2 Lignin in Thermoplastic Composites;190 9.2.1;2.1 Polyethylene/Lignin Composites;190 9.2.2;2.2 Polypropylene/Lignin Composites;192 9.2.3;2.3 Polylactic Acid/Lignin Composites;195 9.3;3 Lignin in Thermoset Composites;198 9.3.1;3.1 Polyurethane/Lignin Composites;198 9.3.2;3.2