Adhesives for Wood and Lignocellulosic Materials. R. N. Kumar

      5  Index

      6  End User License Agreement

      Guide

      1  Cover

      2  Table of Contents

      3  Begin Reading

      List of Illustrations

      1 PrefaceFigure 1 Basic wood elements from largest to smallest (i.e., breakdown of solid wood into…

      2 Chapter 1Figure 1.1 Earlywood and latewood [5].Figure 1.2 Schematic model of the cell wall layers [16].Figure 1.3 Chemical composition of wood.Figure 1.4 The three monolignols.Figure 1.5 Radicals and units—nomenclature.Figure 1.6 Various degradation products of lignin.Figure 1.7 Enzymatic dehydrogenation of coniferyl alcohol yielding phenoxy radicals.Figure 1.8 Typical dilignol structures [25].Figure 1.9 Arrays of cells aligned along the longitudinal and radial directions.

      3 Chapter 2Figure 2.1 Potential energy diagram for different forces [4].Figure 2.2 Various wood elements.Figure 2.3 Wetting phenomenon.Figure 2.4 Wetting, spreading, and dewetting for different contact angles.Figure 2.5 Equilibrium contact angle based on balance of forces.Figure 2.6 Zisman’s plot…Figure 2.7 Different links in adhesive bonding.

      4 Chapter 3Figure 3.1 Reaction between urea and formaldehyde: mononuclear methylol ureas.Figure 3.2 Reaction mechanism.Figure 3.3 Effect of pH on the rate of addition and condensation reactions [24].Figure 3.4 Reaction chemistry.Figure 3.5 Reaction mechanism for chain extension.Figure 3.6 Monomeric species.Figure 3.7 Oligomeric species.Figure 3.8 General chemical structure of commercial UF resin.Figure 3.9 Cross-linked structure of cured UF resin.Figure 3.10 Synthesis of PILs.Figure 3.11 Structure of polyamines.

      5 Chapter 4Figure 4.1 Ammeline, ammelide, and cyanuric acid.

      6 Chapter 5Figure 5.1 Resol, resitol, and resite.Figure 5.2 Resonance structures of phenol.Figure 5.3 Formation of ortho-methylolphenol.Figure 5.4 Mononuclear phenol alcohols.Figure 5.5 Mechanism of methylolphenol formation in alkaline medium.Figure 5.6 Chain extension.Figure 5.7 A dinuclear structure.Figure 5.8 Formation of quinine–methide as intermediate.Figure 5.9 Typical structure of a commercial phenolic resol.Figure 5.10 Structure of ammonia-catalyzed resol.Figure 5.11 Three-dimensional response surface relating the heat of P–F condensation…Figure 5.12 Interaction of resin synthesis, structure, and property relationships [36].

      7 Chapter 6Figure 6.1 Reaction of resorcinol with formaldehyde through its different methylol derivatives…Figure 6.2 Possible quinone methide intermediates formed by reaction of resorcinol with…Figure 6.3 Reaction of resorcinol with formaldehde to form HMR trimer.

      8 Chapter 7Figure 7.1 Isocyanurate and allophenate.Figure 7.2 Aliphatic isocyanates.Figure 7.3 Biuret of HDI.Figure 7.4 TDIs 2,4 and 2,6 isomers (65:35).Figure 7.5 TDIs 2,4 and 2,6 isomers (80:20).Figure 7.6 Polymeric MDI.Figure 7.7 Catalysts for reactions of isocyanates.Figure 7.8 Multiple pathways for the formation of a wood/isocyanate adhesive bond.Figure 7.9 MDI reaction with wood hydroxyls.Figure 7.10 Schematic reaction of formation of a PU from a polyisocianate and a polyol.Figure 7.11 “Green” pressure-sensitive PU adhesive prepared from glycerol and…Figure 7.12 Reaction of P. pinaster bark tannin with propylene oxide to produce…Figure 7.13 Formation of PU adhesive and resins by reaction of a hydroxypropylated polypheno…Figure 7.14 Reaction of the flavonoid tannin/formaldehyde system with isocyanates to form…Figure 7.15 Formation of PU by reaction of a glyoxalated flavonoid tannin with a polyisocyan…Figure 7.16 Non-isocyanate PU formation by reaction of a dicyclic organic carbonate with a…Figure 7.17 Non-isocyanate diurethane obtained by reacting a precarbonated flavonoid tannin…Figure 7.18 Non-isocyanate urethane bridge linking a precarbonated flavonoid tannin dimer…Figure 7.19 Non-isocyanate diurethane obtained by reaction of a carbonated carbohydrate…Figure 7.20 Non-isocyanate diurethane obtained by reaction of a carbonated carbohydrate…Figure 7.21 Examples of linear and branched oligomer structures identified for glucose-based…

      9 Chapter 10Figure 10.1 Hydrophobization of wood.Figure 10.2 Sol-gel reaction scheme.

      10 Chapter 11Figure 11.1 MALDI mass spectrum of (a) natural mimosa tannin extract. (b) Details of the 600…Scheme 11.1

      11 Chapter 12Figure 12.1 Schematic representation of the decomposition of hexamine to iminoamino methylen…Figure 12.2 Dry IB strength as a function of tannin solution pH of laboratory particleboards…Figure 12.3 Dry IB strength of laboratory particleboards prepared with mixtures of different…Figure 12.4