An adhesive composition is disclosed, and includes an aldehyde-based resin selected from the group consisting of urea-formaldehyde resins, melamine-formaldehyde resins, melamine-urea-formaldehyde resins, phenol-containing resins, and mixtures, combinations, and sub-combinations thereof, and a formaldehyde scavenger selected from the group consisting of chitosan, nano-chitosan, functionalized chitosan, and mixtures, combinations, and sub-combinations thereof.

A method of manufacture of medium and high density fibreboard with moisture and mildew resistance and low formaldehyde emission, which includes the steps of: (a) providing wood chips; (b) pre-steaming; (c) refining the wood chips into fibers and adding 250-800 kg/m.sup.3 urea-formaldehyde resin adhesive, mildew inhibiting agent, fireproof bonding agent, nigrosine solution with a mass percentage of nigrosine in absolutely dried fiber of 1-1.2%, 6-8 kg/m.sup.3 refined paraffin and 1.5-2 kg/m.sup.3 curing agent; (d) feeding activated carbon of 100-200 mesh to mix with the fibers and then drying the fibers to a water content between 8-10%; (e) separating qualified fibers to measuring silo; (f) laying the fibers onto a mat formation platform uniformly to form a fiber mat by pre-pressing; (g) pre-heating the fiber mat; and (h) processing continuous hot-pressing to form a raw board. The resulting fiberboard is black in color, has good physical properties and low formaldehyde emission rate.

Composite cellulosic products and processes for making same. In some embodiments, the composite cellulosic product can include a plurality of cellulosic substrates and an at least partially cured binder. Prior to curing, the binder can include a mixture formed by combining magnesium oxide, water, and magnesium chloride. A weight ratio of the magnesium oxide to the magnesium chloride in the binder can be at least 2.2:1 to 8.5:1.

A process for the production of OSB wood-based panels including: a) producing wood strands from suitable wood logs; b) treating at least part of the wood strands with steam at a temperature between 80 C. and 120 C. and a pressure between 0.5 bar and 2 bar; c) drying the steam-treated wood strands; d) gluing the steam-treated and dried wood strands and, optionally, gluing the non-steam treated wood strands with at least one binder; e) scattering the glued wood strands onto a conveyor belt; and f) pressing the glued wood strands into an OSB wood-based board. The steam treatment takes place after the wood strands have been produced and made available, or after the wood strands have been sifted and separated according to the use of the wood strands for the middle and top layers of the panel. Also, an OSB wood-based panel made using the process.

In one embodiment, a method for making a high density structural composite includes depositing a plurality of fibrous materials on or adjacent a first plate or surface. A polymer liquid is deposited onto the plurality of fibrous materials to form a composite mixture. A first cyclic pressure is applied onto the composite mixture to compress the composite mixture. In some embodiments, the cyclic pressure may then be reduced to a valley pressure to complete a pressurization cycle. In some instances, the valley pressure may be below atmospheric pressure to induce trapped air and volatile gases to escape from the composite mixture before curing. The pressurization cycle may be repeated. A second pressure, which may be a constant pressure in some embodiments, may be applied to the composite mixture using, in some embodiments, a second plate until the polymer liquid has at least partially cured or partially solidified.

A curable aqueous composition is disclosed comprising a carbohydrate, a crosslinking agent, and an amine base, wherein the curable aqueous composition has a pH adjusted by the amine base. Further disclosed is a method of forming a curable aqueous solution.

A method for producing wood material boards with reduced emission of volatile organic compounds (VOCs), including: a) producing woodchips from suitable timbers; b) heat-treating at least one portion of the woodchips at a temperature between 150 C. and 300 C. for a period of 1 to 5 hours; c) crushing the wood chips that are not heat-treated and at least one portion of the heat-treated woodchips by machining in order to obtain wood shavings or by solubilizing in order to obtain wood fibers; d) gluing the wood shavings or wood fibers with at least one binding agent; e) applying the glued wood shavings onto a transport belt while forming a multi-layered shavings cake or applying the glued wood fibers onto a transport belt while forming a single-layer fiber cake; and f) compressing the shavings cake or the fiber cake to form a wood material board.

A method for producing a compressed cellulosic fiber product and a compressed cellulosic fiber product manufactured from cellulosic raw material using this method. The method comprises the steps of: (i) providing cellulosic raw material comprising cellulosic fibers; (ii) treating the cellulosic raw material with an adhesive composition to obtain a raw mass; and (iii) compressing the raw mass in a pre-defined form to effect condensation to obtain the compressed cellulosic fiber product.

A method of manufacture of medium and high density fibreboard with moisture and mildew resistance and low formaldehyde emission, which includes the steps of: (a) providing wood chips; (b) pre-steaming; (c) refining the wood chips into fibers and adding 200-230 kg/m.sup.3 urea-formaldehyde resin adhesive, nigrosine solution with a mass percentage of nigrosine in absolutely dried fiber of 1-1.2%, 6-8 kg/m.sup.3 refined paraffin and 1.5-2 kg/m.sup.3 curing agent; (d) feeding activated carbon of 100-200 mesh to mix with the fibers and then drying the fibers to a water content between 8-10%; (e) separating qualified fibers to measuring silo; (f) laying the fibers onto a mat formation platform uniformly to form a fiber mat by pre-pressing; (g) pre-heating the fiber mat; and (h) processing continuous hot-pressing to form a raw board. The resulting fiberboard is black in color, has good physical properties and low formaldehyde emission rate.

A method for producing wood material boards with reduced emission of volatile organic compounds (VOCs), including: a) producing woodchips from suitable timbers; b) heat-treating at least one portion of the woodchips at a temperature between 150 C. and 300 C. for a period of 1 to 5 hours; c) crushing the wood chips that are not heat-treated and at least one portion of the heat-treated woodchips by machining in order to obtain wood shavings or by solubilizing in order to obtain wood fibers; d) gluing the wood shavings or wood fibers with at least one binding agent; e) applying the glued wood shavings onto a transport belt while forming a multi-layered shavings cake or applying the glued wood fibers onto a transport belt while forming a single-layer fiber cake; and f) compressing the shavings cake or the fiber cake to form a wood material board.