Wood Adhesion and Adhesives
نویسنده
چکیده
9.1 General..................................................................................................................................216 9.2 Wood Adhesive Uses............................................................................................................217 9.3 Terminology..........................................................................................................................219 9.4 Application of the Adhesive.................................................................................................220 9.4.1 Adhesive Application to Wood ................................................................................220 9.4.2 Theories of Adhesion ...............................................................................................221 9.4.3 Wood Adhesion ........................................................................................................225 9.4.4 Wood Surface Preparation........................................................................................225 9.4.5 Wood Bonding Surface ............................................................................................226 9.4.6 Spatial Scales of Wood for Adhesive Interaction ....................................................229 9.4.7 Wetting and Penetration in General .........................................................................230 9.4.8 Wetting, Flow, and Penetration of Wood .................................................................231 9.5 Setting of Adhesive ..............................................................................................................234 9.5.1 Loss of Solvents .......................................................................................................235 9.5.2 Polymerization ..........................................................................................................236 9.5.3 Solidification by Cooling .........................................................................................237 9.6 Performance of Bonded Products ........................................................................................238 9.6.1 Behavior under Force ...............................................................................................238 9.6.2 Effect of Variables on the Stress-Strain Behavior of Bonded Assemblies..............................................................................................241 9.6.3 Bond Strength...........................................................................................................242 9.6.4 Durability Testing .....................................................................................................245 9.7 Adhesives..............................................................................................................................246 9.7.1 Polymer Formation ...................................................................................................246 9.7.2 Self-Adhesion ...........................................................................................................248 9.7.3 Formaldehyde Adhesives..........................................................................................249 9.7.3.1 Phenol Formaldehyde Adhesives ..............................................................250 9.7.3.2 Resorcinol and Phenol-Resorcinol Formaldehyde Adhesives..................252 9.7.3.3 Urea Formaldehyde and Mixed Urea Formaldehyde Adhesives .............254 9.7.3.4 Melamine Formaldehyde Adhesives .........................................................255 9.7.4 Isocyanates in Wood Adhesives ...............................................................................257 9.7.4.1 Polymeric Diphenylmethane Diisocyanate...............................................258 9.7.4.2 Emulsion Polymer Isocyanates .................................................................260 9.7.4.3 Polyurethane Adhesives ............................................................................260 9.7.5 Epoxy Adhesives ......................................................................................................261 9.7.6 Polyvinyl and Ethylene-Vinyl Acetate Dispersion Adhesives.................................263 9.7.7 Biobased Adhesives ..................................................................................................265
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