Binder composition comprising alkaline substances for producing lignocellulosic composites, corresponding method, use and product

Abstract

Described herein is a process for producing a lignocellulosic composite material, a binder composition suitable for use in said process, as well as a lignocellulosic composite material that can be produced by the process of the invention and the use thereof. Furthermore, a kit for producing a binder composition for the production of lignocellulosic composites and a corresponding use of such a binder composition are described herein.

Description

[0001] The present invention relates to a method for producing a lignocellulose composite material, a binder composition suitable for the method, and a lignocellulose composite material that can be produced by the method of the present invention and its use. In addition, the present invention relates to a kit for producing a binder composition according to the present invention, the binder composition is used for producing a lignocellulose composite material, and to the corresponding use of such a binder composition.

[0002] Typically, in a method for producing a multilayer or monolayer lignocellulosic composite, a mixture of lignocellulosic particles (i.e. particles consisting essentially of lignocellulose) and a binder is provided or prepared. The mixture is typically dispersed, for example to obtain the first layer of a multilayer mat or to obtain a monolayer mat. When producing a multilayer composite, two or more mixtures of lignocellulosic particles are dispersed in sequence to obtain a mat having two or more individual layers. The resulting mat is then compacted, and during or after compaction, the compacted mat or mixture is hardened, i.e. the mixture is treated in such a way that the binder undergoes a hardening process.

[0003] There is an industrial need for an improved process for producing multi-layer or single-layer lignocellulosic composites, in which binder components can be used which can be obtained to the greatest possible extent from non-petrochemical resources, preferably from renewable resources, and which are suitable for reducing or avoiding potentially harmful substances, like formaldehyde and isocyanates or substances that release formaldehyde, like for example N-methylol compounds, during or after the production process of the composite materials.

[0004] The following documents relate to certain aspects of the method for producing multi-layer or single-layer lignocellulosic composite materials:

[0005] Document US 2011 / 0262648 A1 describes durable thermosets from reducing sugars and primary polyamines.

[0006] Document WO 2015 / 177114 A1 relates to a pre-reacted binder composition based on water-soluble carbohydrate-polyamino acids.

[0007] Document EP 3611225 A2 relates to adhesive compositions, articles and methods for producing articles.

[0008] In view of the existing prior art, there is still a need for improved methods of producing multi-layer or single-layer lignocellulosic composites, wherein binder components obtainable from non-petrochemical resources, preferably from renewable resources, are used as much as possible and wherein harmful or potentially harmful substances are reduced or avoided.

[0009] Accordingly, the main object of the present invention is to provide an improved method for producing a multi-layer or single-layer lignocellulosic composite material, in particular such a method, wherein the resulting lignocellulosic composite material has increased strength when compared to a similar lignocellulosic composite material not produced by the method according to the present invention, or wherein shorter heating and / or pressing times are required to obtain a lignocellulosic composite material having a strength comparable to that of a similar lignocellulosic composite material not produced by the method according to the present invention.

[0010] Another object of the present invention is to provide a binder composition suitable for use in an improved process for producing a multi-layer or single-layer lignocellulosic composite material, and a lignocellulosic composite material produced by said process.

[0011] Yet another object of the present invention is to provide a method for producing a multi-layer or single-layer lignocellulosic composite material and a corresponding binder composition, wherein the binder composition will contain a certain proportion of bio-based components, which proportion should be as high as possible in order to reduce or avoid the emission of harmful or otherwise undesirable volatile compounds during or after production and to allow safe disposal and / or reduce potentially environmentally harmful waste.

[0012] It has now been found that the main object and other objects of the present invention can be achieved by a method for producing a lignocellulose composite material comprising one (particularly a "single-layer lignocellulose composite material") or a plurality of lignocellulose composite layers (particularly a "multi-layer lignocellulose composite material"), the method comprising at least the following steps:

[0013] S1) providing or preparing a mixture comprising at least:

[0014] -Lignocellulosic particles

[0015] as well as

[0016] - a binder composition, preferably an aqueous binder composition (ie a binder composition comprising water), which comprises at least the following as components preferably for hardening the binder or binder composition:

[0017] c1) one or more amino acid polymers having two or more primary amino groups,

[0018] Wherein preferably, the one or more amino acid polymers having two or more primary amino groups are the polymerization products of amino acid monomers and optionally other monomers,

[0019] c2) one or more α-hydroxycarbonyl compounds, and

[0020] c3) One or more pK B Alkaline substances with a value of ≤3,

[0021] S2) compacting the mixture from step S1) to obtain a compacted mixture,

[0022] as well as

[0023] S3) preferably during and / or after compaction in step S2), heat and / or pressure is applied to the mixture so that the binder of the binder composition (preferably the binder or the curable component of the binder composition) hardens and produces a lignocellulosic composite material (or multiple lignocellulosic composite layers).

[0024] The invention as well as preferred variations and preferred combinations of its parameters, features and elements are defined in the appended claims. Preferred aspects, details, modifications and advantages of the invention are also defined and explained in the following description and in the examples shown below.

[0025] The inventors have now found (and shown in the following examples) that the method for producing a multilayer or single-layer lignocellulosic composite material according to the present invention as described herein shows certain improvements over similar methods known from the prior art. In particular, the method according to the present invention produces a lignocellulosic composite material with increased strength (increased internal bond strength) when compared to a similar lignocellulosic composite material not produced according to the method of the present invention, or wherein a shorter heating and / or pressing time is required to obtain a lignocellulosic composite material with a strength comparable to that of a similar lignocellulosic composite material not produced according to the method of the present invention.

[0026] If not stated otherwise, preferred embodiments, aspects or features of the invention may be combined with other embodiments, aspects or features, in particular with other preferred embodiments, aspects or features, regardless of the category to which the embodiments, aspects or features relate. A combination of a preferred embodiment, aspect or feature with other preferred embodiments, aspects or features in each case again results in a preferred embodiment, aspect or feature.

[0027] As used herein, the term "lignocellulose particles" refers to and includes lignocellulose particles of any type, size and shape, such as fiber, debris, strand, flake, sawmill shavings and sawdust or its mixture. In addition, any type of lignocellulose biomass such as birch, beech, alder, pine, spruce, larch, eucalyptus, basswood, poplar, ash, fir, tropical wood, sisal, jute, flax, coconut, kenaf, hemp, banana, straw, cotton stalk, bamboo etc. can be used as the source of the lignocellulose particles. Lignocellulose particles from both primary wood and / or waste wood (such as old furniture) can be used to produce lignocellulose composite materials of the present invention. According to the present invention, a mixture of different types of lignocellulose particles can be used in the production of lignocellulose composite materials.

[0028] As used herein, the term "single-layer lignocellulosic composite" (i.e., a lignocellulosic composite comprising one lignocellulosic composite layer) designates and includes any single-layer composite material containing lignocellulosic particles and a hardened binder that binds the lignocellulosic particles. In addition, the term "single-layer" designates that the lignocellulosic composite material comprises only one layer of lignocellulosic material and a binder, wherein the single-layer is preferably produced by a method comprising a single step of dispersing the lignocellulosic particles. The "single-layer lignocellulosic composite" can have any shape, such as a rectangle, a square, a circle, a triangle, etc. The "single-layer lignocellulosic composite" can also have any thickness, density and color, as long as it contains lignocellulosic particles and a hardened binder. The "single-layer lignocellulosic composite" can also contain several other compounds that are different from the lignocellulosic particles and the binder. The lignocellulosic particles used to produce the "single-layer lignocellulosic composite" are lignocellulosic biomass of the same type or different types (preferred types are described above).

[0029] As used herein, the term "multilayer lignocellulosic composite" (i.e., a lignocellulosic composite comprising more than one lignocellulosic composite layer) designates and includes any multilayer composite material containing lignocellulosic particles and a hardened binder for bonding the lignocellulosic particles, and wherein distinguishable (separate) layers are present within the composite material. The multilayer lignocellulosic composite material preferably comprises at least two distinguishable (separate) layers within the same composite material, in particular a core layer and an upper and lower surface layer; or four or more layers. Adjacent layers of the multilayer lignocellulosic composite material are distinguishable in terms of their composition, density, color or any other characteristic, and the adjacent layers contain the same type of lignocellulosic particles and / or binder or different types of lignocellulosic particles and / or binder. These (separate) layers may also contain or consist of the following materials different from the lignocellulosic particles and / or binder: such as plastics, fabrics, paint coatings, etc., for example foreign matter derived from waste wood. The lignocellulosic particles used to produce the separate layers of the "multilayer lignocellulosic composite material" are lignocellulosic biomass of the same type or different types (preferred types see above). The lignocellulosic particles used to produce the separate / individual layers of the "multi-layer lignocellulosic composite" are of the same or different type of lignocellulosic biomass (preferred types see above) or of the same or different mixtures of two or more such types of lignocellulosic biomass. Furthermore, the term "multi-layer" specifies that the lignocellulosic composite comprises at least two separate layers, wherein at least one, preferably two or more of these separate layers comprise lignocellulosic material and a binder, wherein one or more or all of the layers are preferably produced in a multi-step process which, for each (separate) layer of lignocellulosic material and binder, comprises a step of dispersing the lignocellulosic particles.

[0030] As used herein, the term "one or more amino acid polymers having two or more primary amino groups" (component c1 of the binder composition) designates a polymer compound (i.e., one or more polymer compounds) which is a polymerization product (i.e., a plurality of polymerization products) of an amino acid (preferably an amino acid monomer, more preferably two or more amino acid monomers) and optionally other monomers (wherein the monomers of the polymer compound are preferably linked or bonded to each other via an amide bond), these other monomers are preferably selected from the group consisting of:

[0031] a) an amine comprising at least two amino groups, wherein the amines are not amino acids, and

[0032] b) organic compounds having at least two carboxyl groups, preferably selected from the group consisting of organic dicarboxylic acids and organic tricarboxylic acids, wherein preferably these organic compounds having at least two carboxyl groups are not amino acids,

[0033] Wherein preferably at least 50 wt.-%, preferably at least 75 wt.-%, preferably at least 85 wt.-%, preferably at least 90 wt.-%, preferably at least 95 wt.-%, preferably at least 97.5 wt.-%, preferably at least 99 wt.-%, preferably 100 wt.-% amino acids (preferably amino acid monomers) are used as monomers for the polymerization reaction, based on the total amount (weight) of monomers to form one or more amino acid polymers having two or more primary amino groups.

[0034] As used herein, the terms "wt.-%" and "mass %" are used synonymously.

[0035] Typically and for the purposes of the present invention, the one or more amino acid polymers having two or more primary amino groups may include or consist of dimers (n=2), trimers (n=3), oligomers (n=4-10) and / or macromolecules (n>10), where n is the number of monomers (preferably amino acid monomers) that have been reacted to form the dimers, trimers, oligomers and macromolecules of the one or more amino acid polymers having two or more primary amino groups.

[0036] One skilled in the art will select monomers for producing the amino acid polymer(s) having two or more primary amino groups so as to obtain the desired amino acid polymer(s) having two or more primary amino groups.

[0037] As used herein, the term "one or more amino acid polymers having two or more primary amino groups" also includes derivatives obtained by modifying the one or more amino acid polymers having two or more primary amino groups after polymer synthesis. The modification can be carried out by reacting with the following reagents:

[0038] i) alkyl or alkenyl carboxylic acids such as, for example, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, hexadecenoic acid, stearic acid, oleic acid, linoleic acid and / or linolenic acid and / or Li, Na, K, Cs, Ca or ammonium salts thereof, and / or

[0039] ii) polyalkylene oxides terminated by amino groups and / or acid groups and having one, two or more functionalities, preferably polyethylene oxide, polypropylene oxide and / or polyethylene oxide-propylene oxide, and / or

[0040] iii) alkylene oxides, such as ethylene oxide, propylene oxide and / or butylene oxide, and / or

[0041] iv) lactones, such as ε-caprolactone, δ-valerolactone, γ-butyrolactone, and / or

[0042] v) Alcohols, such as alkanols, for example oleyl alcohol.

[0043] One or more amino acids that can be present as monomers in one or more amino acid polymers with two or more primary amino groups are organic compounds comprising at least one primary amine (-NH2) functional group and at least one carboxyl (-COOH) functional group. The one or more amino acids are preferably selected from the group consisting of: lysine, histidine, isoleucine, leucine, methionine, phenylalanine, threonine, tryptophan, valine, arginine, aspartic acid, glutamic acid, serine, asparagine, glutamine, cysteine, selenocysteine, glycine, α-alanine, β-alanine, tyrosine, γ-aminobutyric acid, ε-aminocaproic acid, ornithine, diaminopimelic acid, 2,3-diaminopropionic acid, 2,4-diaminobutyric acid or its mixture. Amino acid can be used in its L- or D- or racemic form. Amino acid can also be used in its cyclic lactam form, such as ε-caprolactam.

[0044] Preferred amino acids for the polymerization reaction (as monomers for forming the one or more amino acid polymers having two or more primary amino groups) are diamino acids comprising two amine groups, preferably two primary amine groups (-NH2) and at least one carboxyl group (-COOH). Such diamino acids are preferably selected from the group consisting of ornithine, diaminopimelic acid, 2,3-diaminopropionic acid, 2,4-diaminobutyric acid and lysine. Lysine is preferred as an amino acid monomer for forming the one or more amino acid polymers having two or more primary amino groups. For this purpose, L-lysine is even more preferred.

[0045] Preferably, the one or more amino acid polymers having two or more primary amino groups have a molecular weight of 800 g / mol ≤ M w ≤10000 g / mol, preferably 1000 g / mol≤M w ≤8000 g / mol, more preferably 1000 g / mol≤M w ≤5000 g / mol, and still more preferably 1000 g / mol≤M w Weight average molecular weight in the range of ≤3500g / mol.

[0046] The one or more amino acid polymers having two or more primary amino groups may be linear or branched or partially linear and partially branched.

[0047] For the purposes of the present invention, preferred amino acid polymer(s) having two or more primary amino groups are described below.

[0048] As used herein, the term "α-hydroxycarbonyl compound" (component c2) of the binder composition) designates a compound capable of reacting with an amine compound and optionally a further crosslinker to form a hardened binder. The α-hydroxycarbonyl compound may comprise at least one reducing sugar.

[0049] According to the common meaning in the art, the term "reducing sugar" indicates one or more sugars that contain a free aldehyde group, or can be isomerized (ie, tautomerized) to contain a free aldehyde group.

[0050] To be used in component c2) in the binder composition, such one or more alpha hydroxycarbonyl compounds must be capable of reacting with the amino acid polymer having two or more primary amino groups used in component c1).

[0051] The binder composition comprises components c1) one or more amino acid polymers having two or more primary amino groups, and c2) one or more α-hydroxycarbonyl compounds as components preferably used to harden the binder or binder composition. Components c1) and c2) are also referred to herein as "curable components", preferably as "heat-curable components" of the binder or binder composition. More specifically, components c1) and c2) are also collectively referred to herein as "binders", and individually referred to as "curable components", preferably "heat-curable components" of the binder.

[0052] Preferred is the process of the invention as described herein (or as described herein as preferred process of the invention), wherein one or at least one of the plurality of α-hydroxycarbonyl compounds which is component c2) is selected from the group consisting of glycolaldehyde, glyceraldehyde, 1,3-dihydroxyacetone, hydroxyacetone, arabinose, xylose, glucose (dextrose), mannose, fructose, sucrose, ribose, lyxose, galactose, allose, altrose, talose, gulose, idose, psicose, sorbose, maltodextrin, tagatose and mixtures thereof.

[0053] For the purposes of the present invention, more preferred α-hydroxycarbonyl compounds are described below.

[0054] As used herein, the term "pK B "Basic substances with a pK value ≤ 3" include organic and inorganic substances. For the purpose of the present invention, preferred are B Inorganic alkaline substances, especially inorganic hydroxides, having a pK value of ≤ 3. For the purposes of the present invention, the more preferred pK values ​​are described below. B Alkaline substances with a value ≤ 3.

[0055] Preferred is the method of the invention as described herein (or as described herein as preferred method of the invention), wherein the one or more amino acid polymers of component c1) of the binder composition comprises or is one or more polylysine,

[0056] Preferably, one or more polylysine

[0057] - having a weight average molecular weight M of ≥800 g / mol, preferably ≥1000 g / mol, more preferably ≥1150 g / mol w ;

[0058] and / or

[0059] - having a weight average molecular weight M of ≤10000 g / mol, preferably ≤8000 g / mol, more preferably ≤5000 g / mol, and still more preferably ≤3500 g / mol w ;

[0060] and / or

[0061] -With a temperature of 800g / mol≤M w ≤10000 g / mol, preferably 1000 g / mol≤M w ≤8000 g / mol, more preferably 1000 g / mol≤M w ≤5000 g / mol, and still more preferably 1000 g / mol≤M w Weight average molecular weight M within the range of ≤3500g / mol w ;

[0062] and / or

[0063] - contains ≥10 mass %, preferably ≥20 mass %, of lysine monomers as monomers integrated into its polymer structure, based on the total mass of the polymer;

[0064] and / or

[0065] - comprises at least 85 mass %, preferably at least 95 mass %, more preferably at least 99 mass % and still even more preferably 100 mass % of lysine monomers as monomers integrated in the polymer structure, based on the total mass of its polymer structure.

[0066] Preferably, the wt.-% proportion (weight percent) or mass-% proportion (mass percent) of lysine (monomer), preferably L-lysine, in the one or more polylysines can be determined in a manner known per se, for example by complete hydrolysis of the polylysine and subsequent analysis of the resulting monomers by HPLC / MS.

[0067] The weight average molecular weight M of the one or more amino acid polymers (including polylysine) having two or more primary amino groups is w It is preferably determined by size exclusion chromatography (SEC), as generally known in the art and described in more detail in the Examples section below.

[0068] The one or more polylysines may be linear or branched or partially linear and partially branched.

[0069] As used herein, the term "polylysine(s)" designates the polymerization product of the monomeric lysine, preferably L-lysine, and optionally additional monomers selected from the group consisting of:

[0070] a) amino acids,

[0071] b) amines comprising at least two amino groups, wherein these amines are not amino acids,

[0072] as well as

[0073] c) dicarboxylic acids which are not amino acids and tricarboxylic acids which are not amino acids,

[0074] Among them, preferably

[0075] The proportion of lysine used as a monomer for the polymerization reaction to produce polylysine (in mass % (wt.-%)) is ≥10 mass %, preferably ≥20 mass %, based on the total amount of monomers used for the polymerization reaction to produce polylysine,

[0076] or

[0077] At least 85 mass %, preferably at least 95 mass %, more preferably at least 99 mass % and still even more preferably 100 mass % of lysine, based on the total amount of monomers used, is used as monomer for the polymerization reaction to produce the polylysine.

[0078] Preferred for the purposes of the present invention as one or more polylysines are homopolymers of lysine, preferably homopolymers of L-lysine.

[0079] Typically and for the purposes of the present invention, polylysine may include or consist of dimers (n=2), trimers (n=3), oligomers (n=4-10) and / or macromolecules (n>10), where n is the number of lysine monomers that have reacted to form one or more dimers, trimers, oligomers and macromolecules of polylysine. In addition, lysine monomers may be present in a limited amount in a mixture with polylysine, for example due to incomplete conversion of monomers during the polymerization reaction to produce polylysine.

[0080] In the present context, the term polylysine preferably also includes polylysine derivatives which are or can be prepared by: (i) modification reaction of amino groups present in polylysine obtained by polymer synthesis with (ii) electrophiles like carboxylic acids, epoxides and lactones, wherein the total amount of amino groups reacted in the modification reaction is 20% or less, preferably 10% or less, based on the total amount of amino groups in the polylysine obtained in the polymer synthesis (i.e. before modification).

[0081] In our experiments it has been found that the method according to the invention wherein the binder composition comprises as component c1) an amino acid polymer having two or more primary amino groups (in particular one or more polylysines) is suitable for producing a lignocellulose composite material which exhibits increased strength (or requires a shorter pressing time to achieve a similar strength) when compared to similar lignocellulose composite materials in which other amino-functionalized compounds are used in the binder composition. For example, it is reported in WO 2015 / 177114 A1 that a binder composition comprising a lysine monomer and hexamethylenediamine (HMDA) as an amino-functionalized component does not harden satisfactorily in the presence of reducing sugars and sodium hydroxide.

[0082] Also preferred is a method of the invention as described herein (or as described herein as a preferred method of the invention), wherein

[0083] - one or at least one of the plurality of α-hydroxycarbonyl compounds of component c2) of the binder composition is selected from the group consisting of glycolaldehyde, glyceraldehyde, 1,3-dihydroxyacetone, hydroxyacetone, arabinose, xylose, glucose, mannose, fructose, sucrose and mixtures thereof,

[0084] Preferably selected from the group consisting of glycolaldehyde, glyceraldehyde, 1,3-dihydroxyacetone, hydroxyacetone, and mixtures thereof;

[0085] More preferably, one or at least one of the plurality of α-hydroxycarbonyl compounds is hydroxyacetone;

[0086] and / or

[0087] - The ratio of the total mass of (i) one or more amino acid polymers of component c1) of the binder composition: (ii) the total mass of one or more α-hydroxycarbonyl compounds of component c2) of the binder composition or used to prepare the binder composition is in the range of ≥60:40 to ≤90:10, preferably ≥65:35 to ≤80:20, and more preferably ≥65:35 to ≤75:25.

[0088] In our experiments it has been found that particularly high internal bond strengths can be achieved in the lignocellulosic composites produced by the process according to the invention when hydroxyacetone (also known as 1-hydroxy-2-propanone, CAS RN 116-09-6) is used as α-hydroxycarbonyl compound of component c2), or shorter pressing times are required to achieve a defined internal bond strength when compared to the use of a similar binder in which another α-hydroxycarbonyl compound is used instead of hydroxyacetone. Particularly good results (in terms of internal bond strength and / or reduced pressing times) are achieved in the process according to the invention when one or more polylysines are used as component c1) of the binder composition and hydroxyacetone is used as component c2) of the binder composition.

[0089] Similarly, in our experiments it has been found that the best practical results are achieved for the lignocellulosic composites produced by the method according to the invention when the ratio of (i) the total mass of one or more amino acid polymers of the binder composition as component c1): (ii) the total mass of one or more α-hydroxycarbonyl compounds of the binder composition as component c2) is selected within the preferred range outlined above.

[0090] The method of the invention as described herein is also preferred (or as described herein as a preferred method of the invention) wherein

[0091] - One or more pK B Alkaline substances with a pK value ≤ 3 are one or more B Value ≤ 2.5, preferably pK B Substances with a value ≤ 2;

[0092] and / or

[0093] -pK B One or at least one of the plurality of alkaline substances having a value ≤ 3, preferably all of the plurality of alkaline substances are selected from the group consisting of:

[0094] ■ an alkali metal hydroxide, preferably selected from the group consisting of LiOH, NaOH, KOH and mixtures thereof; more preferably NaOH;

[0095] as well as

[0096] ■ an alkaline earth metal hydroxide, preferably selected from the group consisting of Mg(OH)2 and Ca(OH)2 and mixtures thereof, more preferably Ca(OH)2;

[0097] and / or

[0098] - binder composition or component c3) for preparing the binder composition; one or more pK BThe total amount of alkaline substances with a value ≤ 3 (preferably selected from alkali metal hydroxides and alkaline earth metal hydroxides as defined above) is in the range of ≥3 mass % to ≤9 mass %, preferably ≥4 mass % to ≤8 mass %, and more preferably in the range of ≥5 mass % to ≤7 mass %, relative to the total amount of component c1) one or more amino acid polymers of the binder composition and component c2) one or more α-hydroxycarbonyl compounds of the binder composition.

[0099] Furthermore, it has been found in our experiments that the use of one or more pK B Alkaline substances with a value ≤ 3 lead to a still further improvement in the internal bond strength of the lignocellulosic composite material produced by the process according to the invention (or respectively a reduction in the pressing time for achieving a defined internal bond strength), irrespective of the α-hydroxycarbonyl compound used as component c2).

[0100] Furthermore, the method of the invention as described herein is preferred (or as described herein as a preferred method of the invention), wherein the binder composition provided or prepared in step S1) further comprises a carrier liquid, preferably water,

[0101] Among them, preferably

[0102] - component c1) one or more amino acid polymers are present in the binder composition or used for the preparation of the binder composition in a total amount ranging from ≥20 mass % to ≤50 mass %, preferably from ≥25 mass % to ≤45 mass %, and more preferably from ≥25 mass % to ≤40 mass %, relative to the total mass of components c1) to c3) and the carrier liquid;

[0103] and / or

[0104] - Component c2) One or more α-hydroxycarbonyl compounds are present in the binder composition or used for the preparation of the binder composition in a total amount in the range of ≥3 mass % to ≤20 mass %, preferably ≥5 mass % to ≤15 mass %, and more preferably ≥7 mass % to ≤12 mass %, relative to the total mass of components c1) to c3) and the carrier liquid.

[0105] In our experiments it has been found that the best practical results are achieved for the lignocellulosic composite materials produced by the process according to the invention when the binder composition has components c1) and / or c2) in the above defined proportions.

[0106] Furthermore, preferred is the method of the invention as described herein (or as described herein as a preferred method of the invention), wherein in the mixture provided or prepared in step S1) of the method,

[0107] The total amount of component c1) of the binder composition, one or more amino acid polymers, and component c2) of the binder composition, one or more α-hydroxycarbonyl compounds

[0108] The binder composition is present in or used for the preparation of the binder composition in a range of ≥3 mass % to ≤8 mass %, preferably ≥3.5 mass % to ≤7.5 mass %, and more preferably ≥4 mass % to ≤6.5 mass %, relative to the total amount of wood-dried cellulose particles in the mixture.

[0109] Surprisingly, with relatively low total amounts of components c1) and c2) as specified above, sufficiently stable and strong lignocellulosic composites can be obtained for use as lignocellulosic composite boards in many applications, for example in the furniture industry.

[0110] Typically, in step S1) for preparing the mixture, the lignocellulosic particles may be blended with one or more or all components of the binder composition, and / or one or more or all components of the binder composition may be sprayed onto the lignocellulosic particles, with or without premixing of the components of the binder composition prior to blending or spraying.

[0111] However, the method of the invention as described herein is preferred (or as described herein as preferred method of the invention), wherein in step S1), components c1) one or more amino acid polymers having two or more primary amino groups and c3) one or more pK B premixing the alkaline substances with a value of ≤3 with each other, and subsequently contacting the resulting premix with the lignocellulosic particles, preferably spraying them onto the lignocellulosic particles,

[0112] Preferably, component c2) one or more α-hydroxycarbonyl compounds and the premix are contacted with the lignocellulose particles separately, preferably sprayed onto the lignocellulose particles separately,

[0113] Preferably said mixture is allowed to produce.

[0114] Preferably, the composition comprises components c1) one or more amino acid polymers having two or more primary amino groups, and c3) one or more pK BThe premix of an alkaline substance with a value ≤ 3, and preferably water (thereby producing an aqueous premix) has a pH value (after preparation, preferably immediately after preparation and before contacting the premix with the lignocellulosic particles and / or component c2)) in the range of 10 to 14, preferably 11 to 14, more preferably 11 to 13. Preferably, the pH value of the premix, preferably the aqueous premix, is determined at 22°C using an ion-sensitive field effect transistor sensor (preferably Endress+Hauser "Tophit CPS441" model).

[0115] In the method of the present invention, the binder composition may further comprise one, two or more compounds independently selected from the group consisting of alkali metal salts and alkaline earth metal salts (preferably sodium nitrate), hydrophobic agents (preferably paraffin and mixtures containing paraffin, more preferably paraffin emulsions), dyes, pigments, antifungal agents, antibacterial agents, rheology modifiers, fillers, release agents, surfactants and tensides.

[0116] Preferred is the method of the present invention (preferably, as defined herein above as preferred), wherein the method for producing the lignocellulosic composite material comprises steps that are carried out batchwise and / or steps that are carried out continuously. Therefore, the method of the present invention is suitable for a wide variety of different production facilities and provides a variety of options for producing the desired lignocellulosic composite material, i.e. a multilayer lignocellulosic composite material or a single-layer lignocellulosic composite material comprising one or more, preferably two or more, lignocellulosic composite material layers. As a preferred method of the present invention, batch production is selected to produce individual lignocellulosic composite materials, for example with different shapes, thicknesses, etc., while a fully continuous method is preferably selected for the production of more uniform lignocellulosic composite materials, for example with similar shapes, thicknesses, etc.

[0117] The preferred method of the present invention can also and preferably comprises one or more steps carried out in batches, and one or more steps carried out continuously. A preferred example of such a combined method is to produce a single-layer lignocellulose composite material in a method step carried out continuously, and then use the continuously produced single-layer lignocellulose composite material as a starting material (e.g. as the core layer of the multi-layer lignocellulose composite material) to produce a multi-layer lignocellulose composite material in batches (and preferably separately).

[0118] The method of the invention as described herein is also preferred (or as described herein as a preferred method of the invention), wherein the lignocellulosic composite material is a lignocellulosic board selected from the group consisting of:

[0119] - High-density fiberboard (HDF);

[0120] - Medium density fiberboard (MDF);

[0121] - Low-density fiberboard (LDF);

[0122] - wood fiber insulation boards;

[0123] - Oriented Strand Board (OSB);

[0124] - particleboard; and

[0125] - natural fiberboard, preferably with fibers from the group consisting of sisal, jute, flax, coconut, kenaf, hemp, banana and mixtures thereof;

[0126] The wood cellulose board is

[0127] - single-layer wood cellulose board, or

[0128] -Multi-layer wood cellulose board,

[0129] A multi-layer lignocellulosic board having a core layer and having an upper surface layer and a lower surface layer is preferred.

[0130] According to a preferred aspect of the method of the invention, the production method produces a lignocellulosic composite material, i.e. preferably a single-layer lignocellulosic board or a multi-layer lignocellulosic board, more preferably a multi-layer lignocellulosic board. The multi-layer lignocellulosic board is more preferably a board having at least a core layer and an upper surface layer and a lower surface layer. The total number of layers is then three or more. If the number of layers is four or more, one or more intermediate layers are present. Preferred is a three-layer board having a core layer, an upper surface layer and a lower surface layer.

[0131] Therefore, a preferred aspect of the present invention relates to a method for producing high density fiberboard (HDF), medium density fiberboard (MDF), low density fiberboard (LDF), wood fiber insulation board, oriented strand board (OSB), particleboard or natural fiberboard, wherein the board is preferably a single-layer lignocellulosic board or a multi-layer lignocellulosic board, more preferably a multi-layer lignocellulosic board, most preferably a three-layer lignocellulosic board.

[0132] In step S3) of the method of the present invention, preferably during and / or after compacting the mixture in step S2) (preferably during and after compacting the mixture in step S2) or after compacting the mixture in step S2)), heat and / or (preferably "and") pressure is applied to the mixture so that the binder of the binder composition hardens and a lignocellulosic composite material is produced.

[0133] Preferably, a temperature in the range of 80°C to 300°C, more preferably 120°C to 280°C, and even more preferably 150°C to 250°C is applied in step S3) and / or (preferably "and") a pressure in the range of 0.1 to 10 MPa, preferably 0.5 to 8 MPa, and more preferably 1 to 6 MPa is applied in step S3).

[0134] Preferably, the temperature applied in step S3) is measured at the center of the (three-dimensional) lignocellulosic composite material produced at the end of step S3). The lignocellulosic composite material ("board") can be cooled in a star cooler or more slowly by hot stacking. For example, step S3) can be carried out in a conventional hot press.

[0135] The temperature in the center of the lignocellulose composite material can be measured according to known methods, in particular according to the method described by Meyer / Themen, Holz als Roh- und Werkstoff [European Journal of Wood and Wood Products]] (2007) 65, pp. 49-55, or Thomemen, 2010, “Vom Holzzum Werkstoff–Grundlegene Untersuchungen zur Herstellung und Struktur von Holzwerkstoffen [From wood to materials-basic investigations for the preparation and the structure of wood-based materials]]”, ISBN 978-3-9523198-9-5, pp. 24 to 30 and 78 to 85. For wireless measurement of the temperature, sensors such as the CONTI LOG sensor or the EASYlog sensor from Fagus-Grecon Greten GmbH & Co. KG can be used, which can be inserted into the mixture for producing the lignocellulosic composite material, for example, during or after step S1 ).

[0136] In a preferred variant of the method of the invention, step S3) comprises applying a high-frequency electric field to the mixture, preferably during and / or after compaction in step S2), so that the binder hardens and bonds the lignocellulosic particles so as to produce a lignocellulosic composite material (or layers of a multilayer lignocellulosic composite material).

[0137] As used herein, the term "high frequency electric field" designates and includes any kind of high frequency electric field or electromagnetic field, such as microwave radiation or a high frequency electric field, which is generated after applying a high frequency alternating voltage at a plate capacitor between two capacitor plates. Suitable frequencies for high frequency electric fields are in the range of 100kHz to 30GHz, preferably 6MHz to 3GHz, more preferably 13MHz to 41MHz. Particularly suitable and preferred are corresponding domestically and internationally recognized frequencies, such as 13,56MHz, 27,12MHz, 40,68MHz, 2,45GHz, 5,80GHz, 24,12GHz, more preferably 13,56 and 27,12MHz. In the method of the present invention, the electric power for generating such high frequency electric fields is preferably in the range of 10 to 10.000kWh, more preferably 100 to 5.000kWh, most preferably 500 to 2.000kWh.

[0138] Preferred is the process of the invention as described herein (or as described herein as preferred process of the invention), wherein the process for producing a lignocellulosic composite material comprises one, two, three, more than three or all of the following steps

[0139] - preparing a layer of the mixture provided or prepared in step S1), preferably by dispersing, and compacting the layer in step S2),

[0140] - for the preparation of a multilayer lignocellulosic composite material comprising one or more lignocellulosic composite layers at least a first and a second separate mixture are provided or prepared and said first and second separate mixtures are used for making a first layer and a second layer of the multilayer lignocellulosic composite material, wherein the first layer and the second layer are preferably in contact with each other and / or wherein the first and the second separate mixtures have the same composition or have different compositions,

[0141] - for the preparation of a multilayer lignocellulosic composite material, two or more layers are prepared, preferably by dispersing individual layers on top of each other, each layer comprising lignocellulosic particles and a binder, wherein in the two or more layers the lignocellulosic particles and / or the binder are identical or different,

[0142] - in step S2), the mixture is compacted in two stages, wherein in a first stage the mixture is pre-compacted to obtain a pre-compacted mat, and wherein in a second stage the pre-compacted mat is further compacted,

[0143] - hot pressing the mixture during or after compaction in step S2),

[0144] as well as

[0145] - In step S3) a temperature in the range of 80°C to 300°C and a pressure in the range of 0.1 to 10 MPa are applied to the mixture, preferably to the compacted mixture from step S2).

[0146] According to a preferred aspect of the method of the present invention, the method for producing a lignocellulose composite material of the present invention comprises one, two, three or more preferred steps, which are specific embodiments of step S1), S2) or S3), or additional steps. Each of these preferred steps is optional and can be performed alone or in combination with one or more of the other preferred steps.

[0147] One of the preferred steps involves a step S1 of preparing the mixture comprising or consisting of the lignocellulosic particles and the binder composition. According to this preferred aspect, the lignocellulosic particles are blended with one or more or all components of the binder composition, or one or more or all components of the binder composition are sprayed onto the lignocellulosic particles. Specifically, the components of the binder composition are blended or sprayed onto the lignocellulosic particles simultaneously (e.g. in a mixture with each other) or sequentially, preferably sequentially, as further described and outlined above.

[0148] Another preferred step of the invention is the step of preparing a layer of the mixture provided or prepared in step S1), preferably by dispersing, and compacting the layer in step S2). Preparing the layer by dispersing is a preferred additional step for producing the lignocellulosic composite material.

[0149] According to a preferred aspect of the present invention, in order to prepare a multilayer lignocellulose composite material, at least a first and a second separate mixture is provided or prepared. The first and second separate mixtures are then used to make the first layer and the second layer of the multilayer lignocellulose composite material. Preferably, the first layer and the second layer are in contact with each other. According to this preferred aspect, the first and second separate mixtures have the same or different compositions, and even more preferably the first and second separate mixtures have different compositions. Therefore, different separate mixtures and / or layers of the prepared multilayer lignocellulose composite material are preferably different in specific properties such as density, color, etc. and / or they are different in their composition, wherein different compositions are obtained by using different binders, lignocellulose particles and / or other (additional) components such as plastics, fabrics, paint coatings, etc. (e.g., foreign matter derived from waste wood). The separate layers preferably (i) contain different binders and different lignocellulose particles, or (ii) contain the same binder but different lignocellulose particles, or (iii) contain the same binder and the same lignocellulose particles but different ratios.

[0150] According to the preferred method related to the technology of the present invention, the preparation of the multilayer lignocellulose composite material comprises the preparation of two, three or more layers, each layer comprising lignocellulose particles and a binder. Preferably, the lignocellulose particles and / or the binder in the two, three or more layers are the same or different, even more preferably, the lignocellulose particles are different and the binder is different.

[0151] Preferably, in the step S2) of compacting the mixture provided or prepared in the step S1), the compacting of the mixture is performed in two stages. This means that in a first stage the mixture is pre-compacted to obtain a pre-compacted mat, and in a second stage the pre-compacted mat is further compacted. Preferably, the first stage of pre-compacting the mixture to obtain a pre-compacted mat is performed before the step S3) of applying heat and / or pressure. The second stage of further compacting the pre-compacted mat is preferably performed during the step S3) of applying heat and / or pressure. This two-stage compaction allows a flexible method for producing a lignocellulosic composite material or a layer of a lignocellulosic composite material.

[0152] In a preferred method of the present invention, the preparation of a single-layer lignocellulose composite material or a multi-layer lignocellulose composite material comprises the following steps:

[0153] - providing or preparing one, two or more than two mixtures comprising at least lignocellulosic particles according to the invention and a binder,

[0154] - dispersing the mixture / mixtures to obtain one, two or more than two layers, wherein the layer(s) form a mat,

[0155] - in a first compaction step, the single-layer or multi-layer mat is pre-compacted to obtain a pre-compacted mat, and thereafter

[0156] - In a second compaction step, the pre-compacted mat is compacted while applying heat and / or pressure.

[0157] The invention also relates to a binder composition for producing a lignocellulosic composite material as used and defined above in relation to the process according to the invention for producing a lignocellulosic composite material (or to a corresponding binder composition of the invention as described herein as preferred).

[0158] Generally, all aspects of the invention discussed herein in the context of the process for producing a lignocellulosic composite material according to the invention apply mutatis mutandis to the binder composition of the invention, and vice versa.

[0159] The invention further relates to the use of a binder composition according to the invention (or the use of a corresponding binder composition according to the invention as described herein as preferred) in a method for producing a lignocellulosic composite material.

[0160] Generally, all aspects of the invention discussed herein in the context of the method for producing a lignocellulosic composite material according to the invention and / or in the context of the binder composition of the invention apply mutatis mutandis to the binder composition of the invention and vice versa.

[0161] The present invention further relates to a lignocellulosic composite material obtainable or obtained according to the method according to the invention as described herein (or according to the method according to the invention as described herein as preferred), or a building product comprising such a lignocellulosic composite material,

[0162] Wherein preferably, the lignocellulosic composite material is a lignocellulosic board selected from the group consisting of:

[0163] - High Density Fiberboard (HDF),

[0164] - Medium Density Fiberboard (MDF),

[0165] - Low-density fiberboard (LDF),

[0166] - wood fiber insulation boards,

[0167] -Oriented Strand Board (OSB),

[0168] - Particleboard, and

[0169] - natural fiberboard, preferably with fibers from the group consisting of sisal, jute, flax, coconut, kenaf, hemp, banana and mixtures thereof,

[0170] Wherein preferably the lignocellulosic board is

[0171] - single-layer wood cellulose board, or

[0172] -Multi-layer wood cellulose board,

[0173] A multi-layer lignocellulosic board having a core and having an upper surface layer and a lower surface layer is preferred.

[0174] Generally, all aspects of the invention discussed herein in the context of the method for producing a lignocellulosic composite material according to the invention, and / or the binder composition of the invention, and / or the use of the binder composition of the invention apply mutatis mutandis to the lignocellulosic composite material of the invention, and vice versa.

[0175] As used herein, the term "building product" designates a product used in construction such as decking, doors, windows, floors, panels, furniture or furniture parts. The building product of the present invention is preferably selected from the group consisting of furniture and furniture parts.

[0176] As used herein, the term "furniture" designates all kinds of furniture. In the context of the present invention, furniture is preferably selected from the group consisting of chairs, tables, desks, closets, beds and shelves.

[0177] As used herein, the term "building element" designates a lignocellulose composite product (e.g. a board, see above) constituting a part (element) of a building product (e.g. a furniture part). Such building element is preferably a furniture part, and more preferably such furniture part is selected from the group consisting of a shelf, a table top, a side panel or shelf or door of a cabinet and a side wall of a bed.

[0178] The lignocellulosic composite material, in particular the flooring, of the present invention, in particular if it is an element of the building product of the present invention, preferably comprises lignocellulosic particles selected from the group consisting of fibers, chips, strands, flakes, sawmill shavings and sawdust or mixtures thereof. These lignocellulosic particles are preferably derived from any type of lignocellulosic biomass, such as birch, beech, alder, pine, spruce, larch, eucalyptus, linden, poplar, ash, fir, tropical wood, sisal, jute, flax, coconut, kenaf, hemp, banana, straw, cotton stalks, bamboo, etc. or mixtures thereof.

[0179] The lignocellulosic composite material (preferably a board) of the present invention obtainable or obtained according to the method of the present invention is preferably a single-layer lignocellulosic board or a multi-layer lignocellulosic board, more preferably a single-layer lignocellulosic board. The multi-layer lignocellulosic board of the present invention is a board comprising at least two distinguishable (individual) layers. The multi-layer lignocellulosic board is preferably a board having at least one core layer and an upper surface layer and a lower surface layer. The total number of layers is then three or more. If the number of layers is four or more, one or more intermediate layers are present. Preferred is a three-layer board having a core layer, an upper surface layer and a lower surface layer. This is particularly suitable if the lignocellulosic composite material, preferably a board of the present invention is an element of the building product of the present invention.

[0180] Particularly preferred is the single-layer lignocellulosic board of the invention which is a medium density fiberboard (MDF) or a particleboard, even more preferably a medium density fiberboard (MDF), and corresponding building products comprising such a single-layer lignocellulosic board.

[0181] The present invention also relates to the use of a lignocellulosic composite material according to the invention as described herein (or to a corresponding lignocellulosic composite material as described herein as preferred) as a construction element in a building product, preferably selected from products for construction selected from the group consisting of decks, doors, windows, flooring, panels, furniture and furniture parts.

[0182] Generally, all aspects of the invention discussed herein in the context of the method for producing a lignocellulosic composite material according to the invention, and / or the binder composition of the invention, and / or the use of the binder composition of the invention, and / or the lignocellulosic composite material of the invention apply mutatis mutandis to the lignocellulosic composite material of the invention, and vice versa.

[0183] The present invention therefore also relates to a kit for producing a binder composition for the production of lignocellulosic composites, the kit comprising at least the following as spatially separated individual components:

[0184] k1) one or more amino acid polymers having two or more primary amino groups as used in the process for producing a lignocellulosic composite material according to the invention and as defined above in relation to component c1) of the binder composition (or as described herein as preferred corresponding amino acid polymers);

[0185] k2) one or more α-hydroxycarbonyl compounds as used in the process for producing a lignocellulosic composite material according to the invention and as defined above in relation to component c2) of the binder composition (or as described herein as preferred corresponding α-hydroxycarbonyl compounds);

[0186] as well as

[0187] k3) one or more pK B Alkaline substances with a value ≤ 3 as used in the method for producing a lignocellulosic composite material according to the invention and as defined above in relation to component c3) of the binder composition (or as described herein as preferred corresponding alkaline substances).

[0188] Generally, all aspects of the invention discussed herein in the context of the method according to the invention for producing a lignocellulosic composite material, and / or the binder composition of the invention, and / or the use of the binder composition of the invention, and / or the lignocellulosic composite material of the invention, and / or the use of the lignocellulosic composite material of the invention apply mutatis mutandis to the kit of parts of the invention, and vice versa.

[0189] Examples :

[0190] The following examples are intended to further explain and illustrate the present invention without limiting the scope thereof.

[0191] Material:

[0192] The following materials were used in the experiments described below:

[0193] 1) Dextrose monohydrate, Sigma Aldrich, Spain;

[0194] 2) L-lysine solution (50% in water), Archil Daniels Midland Animal Nutrition (ADManimal Nutrition), USA;

[0195] 3) Hydroxyacetone (95%), Alfa Aesar (now ThermoFisher);

[0196] 4) Sodium hydroxide (97% powder), Sigma-Aldrich, USA;

[0197] 5) Spruce wood chips and fibers (lignocellulose particles) from the Institute of Wood Technology Dresden, Germany (Institut für Holztechnologie Dresden):

[0198] Spruce wood chips are produced in a disc chipper. Spruce trunk segments from Germany (length 250 mm) are pressed with their long sides against rotating steel discs, into which radially and evenly distributed knife boxes are inserted, each consisting of a radially arranged cutting knife and several scoring knives placed at right angles thereto.

[0199] The cutting knife separates the chips from the logs, and the scoring knife limits the chip length at the same time. The produced chips are then collected in a silo and subsequently conveyed to a cross impact mill (with screens) for re-shredding according to the chip width. The re-shredded chips are then conveyed to a flash dryer and dried at about 120°C. The chips are then sieved into two useful fractions ("B": ≤2.0mm x 2.0mm and >0.32mm x 0.5mm; "C": ≤4.0mm x 4,0mm and >2.0mm x 2.0mm), a re-shredded coarse fraction ("D": >4.0mm x 4.0mm) and a fine fraction ("A": ≤0.32mm x0.5mm). Part B is suitable as surface layer chips (surface layer chips) for three-layer particle boards, a mixture of 60 wt.-% part B and 40 wt.-% part C is used as chips for single-layer particle boards, but is also suitable as core layer chips (core layer chips) for three-layer particle boards.

[0200] method:

[0201] 1. Measurement of residual particle moisture content

[0202] The moisture content of the lignocellulosic particles (chips or fibers, see above) before applying the binder is measured in accordance with EN 322: 1993 by placing the particles in a drying oven at a temperature of (103 ± 2) ° C until a constant mass is reached. The water content of the particle / binder composition mixture obtained in step S1) is determined in an analogous manner. For this purpose, samples (about 20 g) of the corresponding mixture are weighed under moist conditions (m1) and after drying (m0). The mass m0 is determined by drying at 103 ° C to a constant mass. The water content is calculated as follows: Water content [in wt.-%] = [(m1–m0) / m0]·100.

[0203] 2. Measurement of suppression time factor

[0204] To determine the pressing time factor, a conventional hot press is used. For the purposes of the present invention, the "pressing time factor" is determined as the "pressing time" (i.e. the time from closing to opening of the press) divided by the "target thickness" of the lignocellulosic composite material (board). The target thickness is the thickness of the lignocellulosic composite material at the end of step S3) and is adjusted by the pressing conditions, i.e. by the distance between the top and bottom press plates, which is adjusted by the automatic distance control of the press.

[0205] The pressing time factor is given below in "[sec / mm]", i.e. the time from closing to opening of the press (in [sec]): the target thickness of the pressed board (in [mm]). For example, when making a 10 mm particle board with a pressing time of 120 sec, a pressing time factor of 12 sec / mm is produced.

[0206] 3. Measurement of Density of Lignocellulosic Composites

[0207] The density of the lignocellulosic composites (boards) was measured according to EN 323:1993 and is reported herein as the arithmetic mean of ten 50 x 50 mm samples of the same lignocellulosic composite (board).

[0208] 4. Measurement of transverse tensile strength (“internal bond strength”) of lignocellulosic composites

[0209] The transverse tensile strength ("internal bond strength") of the lignocellulosic composites (boards) was determined according to EN 319:1993 and is reported herein as the arithmetic mean of ten 50 x 50 mm specimens of the same lignocellulosic composite (board).

[0210] 5. Determine the amount of binder or binder composition

[0211] The amounts of binder or binder composition in the examples shown below are reported as the total weight of the sum of the respective components of the binder or binder composition in wt.-%, based on the total dry weight of the lignocellulosic particles (wood particles).

[0212] 6. Determine the weight average molecular weight (M) of polylysine w )

[0213] The weight average molecular weight (M) of polylysine prepared according to this example is w ) is determined by the generally known size exclusion chromatography method under the following conditions:

[0214] Solvent and eluent: 0.1% (w / w) trifluoroacetate, 0.1 M NaCl in distilled water

[0215] Flow rate: 0.8ml / min

[0216] Injection volume: 100 μl

[0217] The samples were filtered using a Sartorius Minisart RC 25 (0,2 μm) filter.

[0218] Column material: Hydroxylated polymethacrylate (TSKgel G3000PWXL)

[0219] Column size: inner diameter 7.8mm, length 30cm

[0220] Column temperature: 35℃

[0221] Detector: DRI Agilent 1100UVGAT-LCD 503 [232nm]

[0222] Calibration was performed using poly(2-vinylpyridine) standards (from Polymer Standards Service GmbH, Mainz, Germany) with molar masses ranging from 620 to 2,890,000 g / mol and pyridine (79 g / mol).

[0223] The upper limit of integration was set to 29.01 mL.

[0224] M w The calculations include lysine oligomers and polymers as well as monomeric lysine.

[0225] Example 1: Synthesis of polylysine

[0226] Example 1a :With M w 2100 Poly-L-Lysine

[0227] 2200g of L-Lysine solution was heated in an oil bath (external temperature 140°C) under stirring. Water was distilled off and the oil bath temperature was raised by 10°C per hour until a temperature of 180°C was reached. The reaction mixture was stirred for another hour at 180°C (oil bath temperature), and the pressure was then slowly reduced to 200 mbar. After reaching the target pressure, distillation was continued for 2 hours. The product was poured out of the reaction vessel while hot, crushed and dissolved in water after cooling to obtain a 50wt.-% poly-L-Lysine aqueous solution (hereinafter "poly-Lysine solution 1a"). The weight-average molecular weight of the resulting poly-L-Lysine was 2100 (see above for determination method).

[0228] Example 1b :With M w 3690 Poly-L-Lysine

[0229] The experiment of Example 1a as described above was repeated. Unlike Example 1a, distillation was continued for 4 hours (instead of 2 hours) after reaching the target pressure. Finally, a 50 wt.-% poly-L-lysine aqueous solution (hereinafter "poly-lysine solution 1b") was obtained. The weight average molecular weight of the obtained poly-L-lysine was 3690 (see above for the determination method).

[0230] Example 1c :With M w 6270 Poly-L-Lysine

[0231] The experiment of Example 1a as described above was repeated. Unlike Example 1a, distillation was continued for 4.5 hours (instead of 2 hours) after reaching the target pressure. A 50 wt.-% poly-L-lysine aqueous solution (hereinafter "poly-lysine solution 1c") was finally obtained. The weight average molecular weight of the obtained poly-L-lysine was 6270 (see above for the determination method).

[0232] Example 2: Single-layer wood cellulose composite material poly-L-lysine / hydroxyacetone (for comparison)

[0233] Example 2a :With M w 2100 poly-L-lysine / hydroxyacetone monolayer wood cellulose composite (for comparison)

[0234] In a mixer, 499 g of polylysine solution 1a (for preparation, see Example 1a above) were sprayed onto 5.56 kg (5.40 kg dry weight plus 160 g water from the residual particle moisture content) of spruce core chips (moisture content 3.0 wt.-%) while mixing. Immediately while mixing, 149 g of hydroxyacetone solution (50 wt.-% in water) were sprayed onto the mixture. Finally, 90 g of water were sprayed onto the mixture while mixing to adjust the final moisture of the resinated chips. After the addition of the water, mixing was continued for 3 min.

[0235] The term "resin-treated crumb" is used herein for a mixture of crumb with a binder composition and additionally added water (and similarly "resination").

[0236] The amount of binder (or the proportion of binder in the final lignocellulosic composite) is calculated as follows:

[0237] [499 g x 0.5 of component c1)] + [149 g x 0.5 of component c2)]: 5400 g of lignocellulosic particles = 6.0%

[0238] The ratio of the binder components is calculated as follows:

[0239] [499 g x 0.5 of component c1)]:[149 g x 0.5 of component c2)] = 77:23

[0240] The moisture content of the mixture provided or prepared in step S1) is calculated as follows:

[0241] Total weight of water = 499 g x 0.5 (from polylysine solution 1a) + 149 g x 0.5 (from hydroxyacetone solution) + 90 g (from additional water) + 160 g (from crumb moisture) = 574 g

[0242] Total weight of solids = 499 g x 0.5 (from polylysine solution 1a) + 149 g x 0.5 (from hydroxyacetone solution) + 5400 g (dry crumbs) = 5724 g

[0243] The moisture content obtained = 574g / 5724g = 10.0%

[0244] The water content was checked and confirmed by a method similar to that performed in EN 322:1993, resulting in a water content of 10%.

[0245] Immediately after the resin treatment, 1.10 kg of the mixture was dispensed into a 30 x 30 cm mold and heated under ambient conditions (0.4 N / mm 2). Subsequently, the pre-pressed chip mat thus obtained was taken out of the mold, transferred to a hot press and pressed to a thickness of 16 mm to obtain a particleboard as a single-layer lignocellulose composite material (referred to as "SLC 2a C (HA)" in Table 1) (pressing plate temperature 210°C, maximum pressure 4 N / mm 2 , the pressing time is shown by the pressing time factor in Table 1 below).

[0246] Example 2b :With M w 3690 poly-L-lysine / hydroxyacetone monolayer wood cellulose composite (for comparison)

[0247] The experiment of Example 2a described above was repeated. Unlike Example 2a, 499 g of polylysine solution 1b was used (for preparation, see Example 1b above). From this experiment a single-layer lignocellulose composite material (referred to as "SLC 2b C(HA)" in Table 1) was obtained.

[0248] Example 2c : Single-layer wood cellulose composite material of poly-L-lysine / hydroxyacetone with Mw=6270 (for comparison)

[0249] The experiment of Example 2a described above was repeated. Unlike Example 2a, 499 g of polylysine solution 1c (for preparation, see Example 1c above) was used. From this experiment a single-layer lignocellulose composite material (referred to as "SLC 2c C(HA)" in Table 1) was obtained.

[0250] Example 3: Single-layer lignocellulose composite material poly-L-lysine / hydroxyacetone (according to the present invention)

[0251] Example 3a :With M w 2100 poly-L-lysine / hydroxyacetone monolayer wood cellulose composite material (according to the present invention)

[0252] 20.0 g of sodium hydroxide was added to 499 g of the polylysine solution 1a and stirred to obtain a polylysine solution 1a-NaOH.

[0253] In the mixer, 519 g of polylysine solution 1a-NaOH were sprayed onto 5.56 kg (5.40 kg dry weight plus 160 g water from the residual particle moisture content) of spruce core chips (moisture content 3.0 wt.-%) while mixing. Immediately while mixing, 149 g of hydroxyacetone solution (50 wt.-% in water) were sprayed onto the mixture. Finally, 90 g of water were sprayed onto the mixture while mixing to adjust the final moisture of the resin-treated chips. Mixing was continued for 3 min after the addition of water.

[0254] From the binder composition prepared above, a single-layer lignocellulosic composite (referred to as "SLC 3a I (HA)" in Table 1) was prepared as described in Example 2a.

[0255] Example 3b :With M w 3690 poly-L-lysine / hydroxyacetone monolayer wood cellulose composite material (according to the present invention)

[0256] The experiment of Example 3a described above was repeated. Unlike Example 3a, 499 g of polylysine solution 1b (for preparation, see Example 1b above) was used (instead of polylysine solution 1a). From this experiment, a single-layer lignocellulose composite material (referred to as "SLC 3b C (HA)" in Table 1) was obtained.

[0257] Example 3c :With M w 6270 poly-L-lysine / hydroxyacetone monolayer wood cellulose composite material (according to the present invention)

[0258] The experiment of Example 3a described above was repeated. Unlike Example 3a, 499 g of polylysine solution 1c (for preparation, see Example 1c above) was used (instead of polylysine solution 1a). From this experiment, a single-layer lignocellulose composite material (referred to as "SLC 3c C (HA)" in Table 1) was obtained.

[0259] Example 4: Single-layer lignocellulose composite material polylysine / dextrose (for comparison)

[0260] In a mixer, 499 g of polylysine solution 1a (50 wt.-% in water) were sprayed onto 5.56 kg (5.40 kg dry weight plus 160 g water from the residual particle moisture content) of spruce core chips (moisture content 3.0 wt.%) while mixing. Immediately, 149 g of dextrose solution (50 wt.-% in water) were sprayed onto the mixture while mixing. Finally, 90 g of water were sprayed onto the mixture while mixing to adjust the final moisture of the resin-treated chips. After the addition of water, mixing was continued for 3 min.

[0261] A single-layer lignocellulosic composite (referred to as "SLC 4C (DEX)" in Table 1) was prepared as described in Example 2 from the binder composition prepared above.

[0262] Example 5: Monolayer lignocellulose composite material polylysine / dextrose (according to the present invention)

[0263] In the mixer, 519 g of polylysine solution 1a-NaOH (for preparation, see Example 3 above) were sprayed onto 5.56 kg (5.40 kg dry weight plus 160 g water from residual particle moisture content) of spruce core chips (moisture content 3.0 wt.-%) while mixing. Immediately while mixing, 149 g of dextrose solution (50 wt.-% in water) were sprayed onto the mixture. Finally, 90 g of water were sprayed onto the mixture while mixing to adjust the final moisture of the resin-treated chips. After the addition of water, mixing was continued for 3 min.

[0264] A single-layer lignocellulosic composite (referred to as "SLC 5I (DEX)") was prepared as described in Example 2 from the binder composition prepared above.

[0265] Example 6: Determination of parameters of lignocellulosic composites

[0266] For the single layer lignocellulosic composites prepared according to Examples 2 to 5, certain board parameters were determined and are shown in Table 1 below:

[0267] Table 1: Parameters of lignocellulosic composites

[0268]

[0269]

[0270] "No board" in Table 1 above means that the resulting material after pressing was not an intact particle board and showed cracking, splitting and / or bursting.

[0271] From the data shown in Table 1 above, it can be seen in particular that the pK B The presence of an alkaline substance (NaOH) with a value ≤ 3 leads to an increase in the internal bonding strength of the lignocellulosic composite material produced in the method.

Claims

1. A method for producing a lignocellulosic composite material comprising one or more lignocellulosic composite material layers, the method comprising at least the following steps: S1) providing or preparing a mixture comprising at least: -Lignocellulosic particles as well as - A binder composition comprising at least the following as components: c1) one or more amino acid polymers having two or more primary amino groups, c2) one or more α-hydroxycarbonyl compounds, and c3) One or more pK B Alkaline substances with a value of ≤3, S2) compacting the mixture from step S1) to obtain a compacted mixture, as well as S3) applying heat and / or pressure to the mixture so that the binder of the binder composition hardens and produces a lignocellulosic composite material.

2. The method according to claim 1, wherein: The one or more amino acid polymers of component c1) of the binder composition comprise or are one or more polylysines, Preferably, the one or more polylysine - having a weight average molecular weight M of ≥800 g / mol, preferably ≥1000 g / mol, more preferably ≥1150 g / mol w ; and / or - having a weight average molecular weight M of ≤10000 g / mol, preferably ≤8000 g / mol, more preferably ≤5000 g / mol, and still more preferably ≤3500 g / mol w ; and / or -With a temperature of 800g / mol≤M w ≤10000 g / mol, preferably 1000 g / mol≤M w ≤8000 g / mol, more preferably 1000 g / mol≤M w ≤5000 g / mol, and still more preferably 1000 g / mol≤M w Weight average molecular weight M within the range of ≤3500g / mol w ; and / or - contains ≥ 10 mass %, preferably ≥ 20 mass %, of lysine monomers as monomers integrated into its polymer structure, based on the total mass of the polymer, and / or - comprises at least 85 mass %, preferably at least 95 mass %, more preferably at least 99 mass % and still even more preferably 100 mass % of lysine monomers as monomers integrated in the polymer structure, based on the total mass of its polymer structure.

3. A method according to any one of the preceding claims, wherein: - the binder composition is one or at least one of the plurality of α-hydroxycarbonyl compounds of component c2) selected from the group consisting of glycolaldehyde, glyceraldehyde, 1,3-dihydroxyacetone, hydroxyacetone, arabinose, xylose, glucose, mannose, fructose, sucrose and mixtures thereof, Preferably selected from the group consisting of glycolaldehyde, glyceraldehyde, 1,3-dihydroxyacetone, hydroxyacetone, and mixtures thereof; More preferably, one or at least one of the plurality of α-hydroxycarbonyl compounds is hydroxyacetone; and / or - The ratio of the total mass of the one or more amino acid polymers of component c1) of the binder composition to the total mass of the one or more α-hydroxycarbonyl compounds of component c2) of the binder composition or used to prepare the binder composition is in the range of ≥60:40 to ≤90:10, preferably ≥65:35 to ≤80:20, and more preferably ≥65:35 to ≤75:

25.

4. A method according to any one of the preceding claims, wherein: - the one or more pK B Alkaline substances with a pK value ≤ 3 are one or more B Value ≤ 2.5, preferably pK B Substances with a value ≤ 2; and / or -These pK B One or at least one of the plurality of alkaline substances having a value ≤ 3, preferably all of the plurality of alkaline substances are selected from the group consisting of: ■ an alkali metal hydroxide, preferably selected from the group consisting of LiOH, NaOH, KOH and mixtures thereof; more preferably NaOH; as well as ■ an alkaline earth metal hydroxide, preferably selected from the group consisting of Mg(OH)2 and Ca(OH)2 and mixtures thereof, more preferably Ca(OH)2; and / or - Component c3) the one or more pK B The total amount of alkaline substances with a value ≤3 is in the range of ≥3 mass % to ≤9 mass %, preferably ≥4 mass % to ≤8 mass %, and more preferably in the range of ≥5 mass % to ≤7 mass %, relative to the total amount of component c1) the one or more amino acid polymers of the binder composition and component c2) the one or more α-hydroxycarbonyl compounds of the binder composition.

5. A method according to any one of the preceding claims, wherein: The binder composition provided or prepared in step S1) further comprises a carrier liquid, preferably water, Among them, preferably - component c1) the one or more amino acid polymers are present in the binder composition or used for the preparation of the binder composition in a total amount ranging from ≥20 mass % to ≤50 mass %, preferably ≥25 mass % to ≤45 mass %, and more preferably ≥25 mass % to ≤40 mass %, relative to the total mass of components c1) to c3) and the carrier liquid; and / or -Component c2) The one or more α-hydroxycarbonyl compounds are present in the binder composition or used for the preparation of the binder composition in a total amount in the range of ≥3 mass % to ≤20 mass %, preferably ≥5 mass % to ≤15 mass %, and more preferably ≥7 mass % to ≤12 mass %, relative to the total mass of components c1) to c3) and the carrier liquid.

6. A method according to any one of the preceding claims, wherein: In the mixture provided or prepared in step S1) of the method, The total amount of component c1) the one or more amino acid polymers of the binder composition and component c2) the one or more α-hydroxycarbonyl compounds of the binder composition The total amount of the lignocellulosic particles in oven-dried state relative to the mixture is in the range of ≥3 to ≤8 mass %, preferably ≥3.5 to ≤7.5 mass %, and more preferably ≥4 to ≤6.5 mass %.

7. A method according to any one of the preceding claims, wherein: In step S1), components c1) and c3) are premixed with one another and the resulting premix is ​​subsequently brought into contact with the lignocellulosic particles, preferably sprayed onto the lignocellulosic particles, Preferably, component c2) and the premix are contacted with the lignocellulose particles separately, preferably sprayed onto the lignocellulose particles, Preferably said mixture is allowed to produce.

8. A method according to any one of the preceding claims, wherein: The lignocellulosic composite material is a lignocellulosic board selected from the group consisting of - High-density fiberboard (HDF); - Medium density fiberboard (MDF); - Low-density fiberboard (LDF); - wood fiber insulation boards; - Oriented Strand Board (OSB); - Particleboard; as well as - natural fiberboard, preferably with fibers from the group consisting of sisal, jute, flax, coconut, kenaf, hemp, banana and mixtures thereof; The wood cellulose board is - single-layer wood cellulose board, or -Multi-layer wood cellulose board, A multi-layer lignocellulosic board having a core layer and having an upper surface layer and a lower surface layer is preferred.

9. A method according to any one of the preceding claims, wherein: The method for producing a lignocellulose composite material comprises one, two, three, more than three, or all of the following steps: - preparing, preferably by dispersing, a layer of the mixture provided or prepared in step S1), and compacting the layer in step S2), - for the preparation of a multilayer lignocellulosic composite material comprising one or more lignocellulosic composite layers, at least a first and a second separate mixture are provided or prepared and the first and the second separate mixture are used for making a first layer and a second layer of the multilayer lignocellulosic composite material, wherein the first layer and the second layer are preferably in contact with each other and / or wherein the first and the second separate mixture have the same composition or have different compositions, - for the preparation of a multilayer lignocellulosic composite material, two or more layers are prepared, preferably by dispersing individual layers on top of each other, each layer comprising lignocellulosic particles and a binder, wherein in the two or more layers the lignocellulosic particles and / or the binders are identical or different, - in step S2), the mixture is compacted in two stages, wherein in a first stage the mixture is pre-compacted to obtain a pre-compacted mat, and wherein in a second stage the pre-compacted mat is further compacted, - hot pressing the mixture during or after compaction in step S2), as well as - In step S3) a temperature in the range of 80°C to 300°C and a pressure in the range of 0.1 to 10 MPa are applied to the compacted mixture from step S2).

10. A binder composition for use in the production of a lignocellulosic composite material as defined in any one of claims 1 to 6.

11. Use of the binder composition according to claim 10 in a method for producing a lignocellulosic composite material.

12. A lignocellulosic composite material obtainable or obtained by the method according to any one of claims 1 to 9, or a building product comprising such a lignocellulosic composite material, Preferably, the lignocellulose composite material is a lignocellulose board selected from the group consisting of -High Density Fiberboard (HDF) -Medium Density Fiberboard (MDF) -Low Density Fiberboard (LDF) -Wood fiber insulation board -Oriented Strand Board (OSB) - Particleboard, and - natural fiberboard, preferably with fibers from the group consisting of sisal, jute, flax, coconut, kenaf, hemp, banana and mixtures thereof, Wherein preferably the lignocellulosic board is - single-layer wood cellulose board, or -Multi-layer wood cellulose board, A multi-layer lignocellulosic board having a core and having an upper surface layer and a lower surface layer is preferred.

13. Use of the lignocellulosic composite material according to claim 12 as a construction element in a building product, preferably selected from products for construction selected from the group consisting of decks, doors, windows, floors, panels, furniture and furniture parts.

14. A kit for producing a binder composition for the production of lignocellulosic composite materials, the kit comprising at least the following as spatially separated individual components: k1) one or more amino acid polymers as defined in any one of claims 1 or 2 having two or more primary amino groups; k2) one or more α-hydroxycarbonyl compounds as defined in any one of claims 1 or 3; as well as k3) one or more pK as defined in any one of claims 1 or 4 B Alkaline substances with a value ≤ 3.

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