A super strong and tough densified wood structure is formed by subjecting a cellulose-based natural wood material to a chemical treatment that partially removes lignin therefrom. The treated wood retains lumina of the natural wood, with cellulose nanofibers of cell walls being aligned. The treated wood is then pressed in a direction crossing the direction in which the lumina extend, such that the lumina collapse and any residual fluid within the wood is removed. As a result, the cell walls become entangled and hydrogen bonds are formed between adjacent cellulose nanofibers, thereby improving the strength and toughness of the wood among other mechanical properties. By further modifying, manipulating, or machining the densified wood, it can be adapted to various applications.

A heat insulation material is provided that is produced by drying a fibrous matrix impregnated with a solution of pseudo-peptides of formula (I), wherein: R is a side-chain of a natural or synthetic amino acid , R1 is either a linear or branched (C.sub.1-C.sub.3)alkyl group, or a linear or branched (C.sub.1-C.sub.3)alcoxy group, or an aryl group, or an aryl(C.sub.1-C.sub.3)alkyl group, or an aryloxy group, or a saturated or unsaturated heterocycle, n=1 or 2, and A is an aromatic or heteroaromatic group with at least one cycle.

A two-part flame-retardant, a flame-retardant oriented strand (OSB) and method for forming a flame-retardant OSB is provided. The two-part flame-retardant composition includes an aqueous solution containing a water-soluble flame-retardant and a flame-retardant powder that is incorporated into an oriented strand board without substantially affecting the mechanical properties of the oriented strand board. The method includes applying the aqueous solution containing a water-soluble flame-retardant to an oriented strand board furnish and applying a flame-retardant powder to the wetted furnish, without requiring an additional drying step.

The disclosure relates to a method for continuous acetylation of wood elements. The acetylation is conducted with an acetylation medium at a pressure of at least 1.5 barg in a substantially oxygen free environment. Alternatively, the method includes the steps of: (a) feeding wood elements in a substantially oxygen free environment to a continuous acetylation reactor, and (b) treating the wood elements with an acetylation medium in the continuous acetylation reactor under wood acetylation reaction conditions, at a pressure of at least 1.5 barg. The process can acetylate wood elements to a high acetyl content in an efficient way, without compromising on the quality of the material. The acetylated wood elements can be used in the production of medium density fibreboards with superior qualities such as dimensional stability and durability.

A process for the production of acetylated wood elements, a cooling system and a wood acetylation plant are described. A process for the production of acetylated wood elements comprises acetylating wood elements and cooling the acetylated wood elements wherein the cooling comprises supplying liquid water to the acetylated wood elements to provide wetted wood elements and exposing the wetted wood elements to a gas flow.

A super strong and tough densified wood structure is formed by subjecting a cellulose-based natural wood material to a chemical treatment that partially removes lignin therefrom. The treated wood retains lumina of the natural wood, with cellulose nanofibers of cell walls being aligned. The treated wood is then pressed in a direction crossing the direction in which the lumina extend, such that the lumina collapse and any residual fluid within the wood is removed. As a result, the cell walls become entangled and hydrogen bonds are formed between adjacent cellulose nanofibers, thereby improving the strength and toughness of the wood among other mechanical properties. By further modifying, manipulating, or machining the densified wood, it can be adapted to various applications.

A two-part flame-retardant, a flame-retardant oriented strand (OSB) and method for forming a flame-retardant OSB is provided. The two-part flame-retardant composition includes an aqueous solution containing a water-soluble flame-retardant and a flame-retardant powder that is incorporated into an oriented strand board without substantially affecting the mechanical properties of the oriented strand board. The method includes applying the aqueous solution containing a water-soluble flame-retardant to an oriented strand board furnish and applying a flame-retardant powder to the wetted furnish, without requiring an additional drying step.

The present invention provides a method for the acetylation of wood comprising treating the wood with an acetylation medium under wood acetylation reaction conditions and drying the acetylated wood, wherein the drying comprises at least two steps, wherein the wood is first dried with a first drying medium and then with a second drying medium.

A flexible structure is formed by subjecting cellulose-based natural wood material to a chemical treatment that partially removes hemicellulose and lignin therefrom. The treated wood has a unique 3-D porous structure with numerous channels, excellent biodegradability and biocompatibility, and improved flexibility as compared to the natural wood. By further modifying the treated wood, the structure can be adapted to particular applications. For example, nanoparticles, nanowires, carbon nanotubes, or any other coating or material can be added to the treated wood to form a hybrid structure. In some embodiments, open lumina within the structure can be at least partially filled with a non-wood substance, such as a flexible polymer, or with entangled cellulose nanofibers. The unique architecture and superior properties of the flexible wood allow for its use in various applications, such as, but not limited to, structural materials, solar thermal devices, flexible electronics, tissue engineering, thermal management, and energy storage.

A durable palm fiber composite material is obtained by impregnating an unprocessed palm bark in a resin adhesive solution prepared by using a palm leaf as a raw material and then hot-pressing. The palm bark is dried under a natural state without additional processing. The palm leaf is made into a tannin resin adhesive solution under the effect of additives such as furfuryl alcohol, paraformaldehyde, and others. A pH value of the adhesive solution is controlled to be 9-11. A solid content is 40-60%. An adhesive amount applied to the palm bark by the resin adhesive solution is 800-1500 g/m.sup.2. Odd number of layers (three or more layers) of palm barks that are impregnated by the resin adhesive solution and are hot-pressed to the composite material. Hot-pressed parameters are as follows: the temperature is 150-180° C. the unit pressure is 0.8-1.5 MPa, and the time is 10-30 s/mm.