Method of manufacturing composite products comprising a carbohydrate-based binder

Abstract

The present invention relates to the use of an amine compound comprising at least one, preferably at least two amine functions, wherein the amine functions are primary or secondary amines, to reduce the level of furfural and/or hydroxymethylfurfural in a carbohydrate-based binder or binder composition and/or escaping in the course of preparation, cross-linking and/or curing of carbohydrate-based binders. Preferably, the carbohydrate-based binder is obtained from a carbohydrate-based binder composition comprising a carbohydrate component and a cross-linker and possibly reaction product of carbohydrate component and cross-linker, wherein the cross-linker is selected from ammonium salts of inorganic acid, carboxylic acids, salts, ester or anhydride derivatives thereof, and/or combinations thereof.

1 . A method for the preparation of a composite product comprising fibers and/or particles and/or sheet material bonded with a carbohydrate-based binder comprising (i) providing a binder composition comprising a carbohydrate component and at least 10% by dry weight of the binder composition and less than 50% by dry weight of the binder composition of a cross-linker and, optionally, a reaction product of the carbohydrate component and the cross-linker, wherein the carbohydrate component is derived from higher molecular weight carbohydrates wherein the level of C5-sugars or five membered ring sugars varies from 10 to 70 wt. %, and wherein the cross-linker is selected from ammonium salts of inorganic acids, carboxylic acids, ammonium salts thereof, ester or anhydride derivatives thereof, and/or combinations thereof, (ii) adding to the binder composition an additional amount of from 0.5 to 10 wt. % (based on the total dry weight of the binder composition) of an amine compound comprising at least two amine functions, wherein the amine functions are primary or secondary amines, and the amine compound is selected from (a) aliphatic monoamines, the aliphatic group being a straight or branched saturated or unsaturated alkyl or hetero-alkyl chain having 2 to 24 C-atoms or cycloalkyl or cyclohetero-alkyl or an aromatic carbon ring structure, each optionally substituted by hydroxy, carboxyl, halo, cyanate, sulfonyl or thiol, (b) compounds of general formula H 2 N-Q-NH 2  wherein Q is a straight or branched alkyl or heteroalkyl having 2 to 24 C-atoms, cycloalkyl, or cylcoheteroalkyl, an aromatic carbon ring structure, optionally substituted by hydroxy, carboxyl, halo, cyanate, sulfonyl and/or thiol, (c) whey or soy protein, optionally modified or denatured, (d) poly(primary amines) having a molecular weight of 5000 or less and 10 wt. or more of primary amine groups based on the weight of the polyamine, (e) polyamino acids selected from lysine, ornithine, diaminobutyric acid and diaminopropionic acid, or (f) urea, (iii) applying the composition obtained under (ii) onto the fibers, particles and/or sheet material, and (iv) subjecting the product obtained under (iii) to heat and optionally pressure to effect drying and/or curing. 
     
     
         2 . The method according to  claim 1 , wherein the cross-linker is ammonium sulphate or ammonium phosphate. 
     
     
         3 . The method according to  claim 1 , wherein the cross-linker is a carboxylic acid, ammonium salts thereof, or ester or anhydride derivatives thereof. 
     
     
         4 . The method according to  claim 1 , wherein the carbohydrate is selected from monosaccharides, disaccharides, oligosaccharides and polysaccharides and/or combinations thereof. 
     
     
         5 . The method according to  claim 1 , wherein the carbohydrate component is a polysaccharide selected from or derived from molasses, starch, starch hydrolysates, dextrines and derivatives thereof, cellulose hydrolysates, hemicellulose hydrolysates or mixtures thereof. 
     
     
         6 . The method according to  claim 1 , wherein the carbohydrate component is present in an amount ranging from 30% by dry weight of the binder composition to less than 97% by dry weight of the binder composition. 
     
     
         7 .- 11 . (canceled) 
     
     
         12 . A method to reduce the level of furfural and/or hydroxymethylfurfural in a carbohydrate-based binder composition or binder and/or escaping from carbohydrate-based binders in the course of preparation, cross-linking and/or curing thereof, comprising the addition of an amine compound comprising at least two amine functions, wherein the amine functions are primary or secondary amines, to the binder composition during binder preparation and prior to curing, wherein the amine compound is selected from (a) aliphatic monoamines, the aliphatic group being a straight or branched saturated or unsaturated alkyl or hetero-alkyl chain having 2 to 24 C-atoms or cycloalkyl or cyclohetero-alkyl or an aromatic carbon ring structure, each optionally substituted by hydroxy, carboxyl, halo, cyanate, sulfonyl or thiol, (b) compounds of general formula H 2 N-Q-NH 2  wherein Q is a straight or branched alkyl or heteroalkyl having 2 to 24 C-atoms, cycloalkyl, or cylcoheteroalkyl, an aromatic carbon ring structure, optionally substituted by hydroxy, carboxyl, halo, cyanate, sulfonyl and/or thiol, (c) whey or soy protein, optionally modified or denatured, (d) poly(primary amines) having a molecular weight of 5000 or less and 10 wt. % or more of primary amine groups based on the weight of the polyamine, (e) polyamino acids selected from lysine, ornithine, diaminobutyric acid and diaminopropionic acid, or (f) urea, wherein the carbohydrate-based binder is obtained from a carbohydrate-based binder composition comprising a carbohydrate component and at least 10% by dry weight of the binder composition and less than 50% by dry weight of the binder composition of a cross-linker and, optionally, a reaction product of the carbohydrate component and the cross-linker, wherein the cross-linker is selected from ammonium salts of inorganic acids, carboxylic acids, ammonium salts thereof, ester or anhydride derivatives thereof, and/or combinations thereof, wherein the carbohydrate component is derived from carbohydrates wherein the level of C5-sugars or five membered ring sugars varies from 10 to 70 wt. %, and wherein the amine compound is used in an amount of from 0.5 to 10 wt. % based on the total dry weight of the binder composition. 
     
     
         13 . The method according to  claim 12 , wherein the amine compound is a poly(primary amine) having a molecular weight of 5000 or less and 10 wt. % or more of primary amine groups based on the weight of the polyamine, wherein the poly(primary amine) is selected from polyetheramines, polyethyleneimines, polyethyleneimine-containing copolymers and block copolymers, polyvinylamines, and (co)polymers of aminoethyl methacrylate. 
     
     
         14 . The method according to  claim 12 , wherein the carbohydrate component is present in an amount ranging from 30% by dry weight of the binder composition to less than 97% by dry weight of the binder composition. 
     
     
         15 .- 24 . (canceled) 
     
     
         25 . The method according to  claim 1 , wherein the amine compound is a poly(primary amine) having a molecular weight of 5000 or less and 10 wt. % or more of primary amine groups based on the weight of the polyamine, wherein the poly(primary amine) is selected from polyetheramines, polyethyleneimines, polyethyleneimine-containing copolymers and block copolymers, polyvinylamines, and (co)polymers of aminoethyl methacrylate.