Acetylated Wood and Method of Making Same

• Main Authors: Van Dommele, Stefan, Kappen, Theodorus Gerardus Marinus Maria
• Format: Patent
• Language: English
• Published: 27.05.2021
• Subjects: CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW ORSIMILAR MATERIALS; CHEMISTRY; COMPOSITIONS BASED THEREON; DERIVATIVES OF NATURAL MACROMOLECULAR COMPOUNDS; METALLURGY; NAILING OR STAPLING MACHINES IN GENERAL; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FORIMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILARMATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITHPERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL

Disclosed is a process for the acetylation of wood. The wood to be acetylated is first subjected to an extraction step. The resulting extracted wood particularly has a reduced hemicellulose content. This extracted wood is subjected to contact with an acetylation agent. The extraction can be done with an extraction fluid which is, e.g., water, acetone, ethanol, methanol, or acetic acid. The water can be pure water, such as tap water or demineralised water, or it can be a dilute salt solutions (e.g. water containing ammonium oxalate or sodium sulphite). Hot water extraction is preferred. The resulting acetylated extracted wood, particularly wood elements, have a desirable swelling behaviour at lower acetyl contents than conventional acetylated wood. The wood can be in the form of wood elements, solid wood, or wood veneers.