EP1716995B1 - Composition based on fatty acids and paraffin derivatives for protecting lignocellulosic materials - Google Patents

Description

The present invention relates to composite materials of wood particles mixed with plastic and / or adhesive.

The composites of the invention have as a base plastic and / or adhesive in admixture with wood material having a C6 to C40 hydrocarbon comprising hydroxyl reactive groups.

State of the art

It is known that lignocellulosic materials, in particular wood and wood-based materials absorb ambient moisture and are subject to dimensional changes in the case of fluctuations in the moisture content. This leads in particular to wood for swelling and shrinking, as a result to cracking and plating applied to their chipping. Furthermore, lignocellulosic materials, in particular wood, the infestation by fungi, on the one hand by wood-destroying fungi such as Basidiomycetes, on the other hand by discolouring fungi, such as blue fungus and mold.

Known wood preservatives on an organic basis are used to prevent fungal attack. These are generally used for wood in hazard classes 2 and 3 according to DIN 68800/3 and EN 335, have a relatively low molecular weight and are monomeric. They are absorbed by the microorganisms and have a biocidal effect. These are, for example, 3-iodo-2-propynyl-butyl-carbamate (IPBC), triazoles (propiconazole, tebuconazole) or copper salts.

A disadvantage of these biocidal wood preservatives is that the dimensional stability of wood is not improved in the event of moisture fluctuations.

The WO 03/024680 describes a wood preservative comprising a mixture of tall oil with at least 10% by weight of rosin acids, in particular for pressure impregnation of wood, followed by a heating step to at least 100 ° C.

The DE 198 29 037 discloses preservatives for wood from montan wax, terpene-containing montan wax fractions, paraffin, optionally hydrocarbon wax, optionally carboxylic acids (stearic acid) and optionally other water-repellent substances with the example of coffee wax. As the biocidal active ingredient, furthermore, copper, chromium and arsenic compounds, aroma, bitter and / or other pest repellents, for example essential oils, may be present as customary.

The DE 40 36 508 discloses active ingredients for oily wood preservative formulations directed against wood destroying and wood discoloring fungi.

Hill et al. (Wood Research 427-433 (1998 )) describe the chemical modification of softwood with dicarboxylic acid anhydrides to increase the dimensional stability.

The WO 2005/009700 A1 describes hydrophobing with a sizing agent, for example alkyl ketene dimer and / or alkenyl succinic anhydride.

The WO 01/23154 A1 describes the treatment of lignocellulosic materials with hydrophobing agents, for example hydrophobic hydrocarbon chains or a fluoroalkyl polymer.

The DE 1 492 507 describes the treatment of wood materials with isocyanates or diisocyanates for hydrophobing.

The GB 2 200 917A describes the preparation of a plastic woody material from wood particles treated with a polybasic acid anhydride and an unsaturated monoepoxy compound at 120 ° C to 180 ° C under pressure.

The summary of the JP 19870008799 describes the impregnation of wood with an alkyl ketene dimer followed by heat treatment to increase the weathering resistance.

The summary of the JP 19900173798 describes the impregnation of wood with substituted succinic anhydrides to react with hydroxyl groups of the wood.

The DE 921 051 describes moldings made of wood parts, which are glued together by means of urethanes and formaldehyde to form so-called chipboard. In addition to the urethanes and formaldehyde, condensable methylol compounds can still be used as resins.

The DE 100 48 197 A1 describes wood fiber boards of wood particles, which are first acetylated by impregnation with a solution of acetic anhydride and then dried at 140 ° C. The acetylated wood fibers are sprayed with a binder resin and then pressed at elevated temperature to a fiberboard.

The DE 39 27 108 A1 discloses a microbicidal wood preservative with water-soluble cationic or cationizable microbicidal compounds which are water-insoluble by binding to a rosin acid or its derivative. As a microbicidal compound coupled to rosin acid, there are mentioned chloroacetamide, quaternary ammonium compounds such as substituted dimethylbenzylammonium salt, eg, alkyldimethylbenzylammonium chloride.

The WO 98/24603 relates to the use of boric acid triesters of hydrophobic hydrocarbon acids having from 5 to 60 carbon atoms, which may optionally be hydroxy-, carboxy- and / or amino-functionalized, for the hydrophobization of wood.

The DE 40 20 495 A1 uses isocyanate-modified linseed oil mixed with a siccative in a solvent of aliphatic, hydrocarbon-free liquids in admixture with a finely divided paraffin, wax or polyolefin dispersion. In addition, N, N-diaryl-N'-aryl-N '- (trihalomethylthio) sulfamide may be added as biocide.

The US 4,360,385 discloses wood treatment compositions comprising a hydrophobic substance from the group of α-olefins or paraffin fractions, as well as a preservative from the group of wood preservatives, alkyd resins, quaternary ammonium halides, sulfates and hydroxides, as well as alkyl and aryl esters of phosphorus-containing and sulfur-containing acids in mixture with organic solvent.

The summary of JP 01174404 A describes an agent for treating wood with epoxidized higher fatty acid esters obtainable by reacting epoxidized linseed oil with PT-octylphenol and formalin in acid. By impregnating wood and drying at 140 ° C, the wood is first modified by the epoxidized fatty acid ester, which then polymerize and cure epoxidized fatty acid esters and novolac resin.

The WO 03/024681 A1 relates to a wood preservative based on fatty acids and / or resin acids which are at least partially saponified, with the counterion being calcium and / or aluminum.

Furthermore, from the DE 1492507 known to produce particleboard by sticking wood particles, being used as an adhesive in particular formaldehyde resin. However, this frequently used, because inexpensive adhesive has the disadvantage that chips produced therewith swell in high humidity, especially when in contact with water.

Object of the invention

The object of the present invention is to provide wood-plastic composite materials (WPCs) which have a reduced water absorption, in particular in connection with substantially constant or improved Strength properties compared to conventional WPCs. Such composite materials contain, in addition to wood particles, a synthetic polymer, for example a thermoplastic such as polyethylene, polypropylene, other polyolefins, polystyrene, polyvinyl, polyvinyl chloride or copolymers thereof, alternatively thermosets, for example polyamides, alkyd or phenolic resins.

General description of the invention

To solve the above object, the invention provides preservatives for the treatment of wood mixed with plastic and / or adhesive based on hydrocarbons in the form of functionalized reactive fatty acid derivatives, which are dispersed by protective colloids as dispersion or emulsion and in admixture with zirconium and / or Aluminum salt in aqueous mixture are available.

The protective agent can be applied to the lignocellulosic material by impregnation, for example under applied vacuum or pressure, dipping or brushing.

The present invention provides protective agents based on fatty acid derivatives and paraffin, which are particularly suitable for protecting lignocellulosic materials, since they can be applied or impregnated in aqueous and / or solvent-containing composition or from supercritical CO ₂ on the lignocellulosic material On the other hand, they bind with the lignocellulosic material, which can be attributed to physical interactions and, as the inventors believe, to chemical interactions. As a result, the lignocellulosic materials according to the invention a durable protection against attack by microorganisms, especially against molds, and in combination with the fungicidal effect increased dimensional stability in the event of moisture fluctuations.

The use of these protectants to treat wood particles in particle board or WPCs increases their resistance to moisture and liquid water, as well as their resistance to fungal attack. The strength properties of these composite materials are not significantly impaired by the inventive protective agents, preferably improved.

In a preferred embodiment, the protective agents of the invention may be used as aqueous preparations, i. aqueous mixtures, or dispersion / emulsion of hydrocarbons, which are reinforced by derivatization or by mixing with metal cations for the treatment of wood and wood-based materials in their hydrophobizing and fungi-action against conventional water repellents. The hydrocarbon portion of the protecting agent, i. the fatty acid radical is preferably straight-chain with 8 to 50, preferably to 40 or to 20 carbon atoms and unsaturated, preferably saturated. The hydrocarbon moiety is substituted, preferably derivatized with branched, preferably straight-chain, saturated or unsaturated hydrocarbon chains.

According to the invention, the derivatization of the hydrocarbon portion is carried out so that the protective agent has groups that can react with lignocellulose, namely N-methylol groups.

In a preferred embodiment, the protective agents contain catalysts which promote the reaction of the derivatized hydrocarbon moiety with lignocellulosic hydroxyl groups. Catalysts for protecting agents containing reactive N-methylol groups are metal salts from the group of metal halides, metal sulfates, metal nitrates, Metalltetrafluoroborate, metal phosphates or mixtures thereof. examples are Magnesium chloride, zinc chloride, lithium chloride, lithium bromide, boron trifluoride, aluminum chloride, aluminum sulfate, zinc nitrate, sodium tetrafluoroborate or mixtures thereof. Suitable catalysts are also ammonium salts from the group of ammonium chloride, ammonium sulfate, ammonium oxalate, diammonium phosphate or mixtures thereof. Other suitable catalysts are organic or inorganic acids, for example maleic acid, formic acid, citric acid, tartaric acid, oxalic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, boric acid or mixtures thereof. Magnesium chloride, zinc chloride, magnesium sulfate, magnesium nitrate and / or aluminum sulfate are preferably used, particularly preferably magnesium chloride.

This catalyst is used in a concentration of 0.1 to 10 wt .-%, preferably 0.2 to 8 wt .-%, particularly preferably 0.3 to 5 wt .-%, based on the protective agent.

In addition to the abovementioned hydrocarbons, paraffins according to the invention are used in admixture with zirconium and / or aluminum salt in an aqueous mixture. The aqueous mixture of paraffin is a finely divided suspension or a colloidal mixture of paraffin in water. To stabilize this finely divided mixture or colloidal distribution or emulsion emulsifiers or detergents can be used, but preferably protective colloids. Because protective colloids make it possible to break the emulsion or the colloidal fine distribution on the wood or wood-based material and to deposit the paraffin. In contrast to emulsifiers or detergents, the protective colloids have a lower tendency to leach, so that the hydrophobing and antiperspirant effect of the paraffin is more stable or durable. The addition of zirconium or aluminum salts to the aqueous paraffin mixture leads to the use of paraffin alone to increase the hydrophobizing effect. Moreover, the content of the aqueous paraffin mixture of aluminum and / or zirconium salt also leads to an increase in the fixation of the hydrocarbon and thus to increase the resistance to leaching of hydrocarbons, e.g. Paraffin in wood and wood-based material. At present, this effect of aluminum and / or zirconium salt is attributed to the formation of hydrogen bonds between hydrocarbon and wood or wood content in the wood material.

Preferably, aluminum and / or zirconium salts in proportions of 0.01 to 3 wt .-%, preferably 0.1 to 1 wt .-%, more preferably used to 0.3 wt .-% of the emulsion. Preferred salts are aluminum hydroxide, aluminum phosphate, aluminum acetate and formate, Al ₂ O ₃ in formic or acetic acid or aluminum chloride, alum, zirconium chloride, oxychloride, acetate and zirconium sulfate.

Detailed description of the invention

The protective agents from which an aqueous dispersion or emulsion can be prepared are obtainable inter alia by reacting fatty acids with melamine which is at least partially reacted with formaldehyde, the reaction product optionally being reactable with methanol. For this reaction, it is also possible to use fatty acid amides and / or fatty alcohols instead of fatty acids.

Furthermore, preservatives are obtainable by reacting fatty acid amides with formaldehyde or by reacting fatty acid-urea compounds with formaldehyde.

According to the invention, the protective agent contains hydrocarbons which are obtainable by reaction of fatty acids and / or fatty acid amides and / or fatty alcohols with N-methylolated amino compounds, preferably melamine which is at least partially reacted with formaldehyde, in accordance with the reaction scheme shown below by way of example:

Furthermore, reaction products with N-methylolated amino compounds, e.g. Melamine, oligomeric or polymerize to form oligomers or polymers. The formation of these oligomers or polymers preferably proceeds autocatalytically and can be enhanced by the addition of bifunctionalized compounds which act as crosslinkers, e.g. C1 to C8 diaminoalkanes and / or urea.

As a further modification of reaction products with N-methylolated amino compounds, e.g. Melamine, is substoichiometrically added to the free amino groups formaldehyde, so that the reaction products still have at least one free amino group, which react with the added fatty acids and / or fatty acid anhydrides or chlorides. As a result, amide bonds are also formed between N-methylolated amino compound and fatty acid residue.

As an alternative to treatment with the protective agent lignocellulosic material is treated with the reaction components of the protective agent, eg mixtures of the fatty acid reacted hydrocarbon with the derivatizing component of the fatty acid, for example melamine, which is at least partially N-methylolated by reaction with formaldehyde, or fatty acid amide or Fatty acid urea with formaldehyde as derivatizing ingredient. Preferably, the mixtures of the reaction components of the protective agent are used to treat the lignocellulosic material in combination with a catalyst which catalyzes the reaction with the lignocellulosic hydroxyl groups. Also suitable for this embodiment of the invention are metal salts from the group of metal halides, metal sulfates, metal nitrates, metal tetrafluoroborates, metal phosphates or mixtures thereof. Examples are magnesium chloride, zinc chloride, lithium chloride, lithium bromide, boron trifluoride, aluminum chloride, aluminum sulfate, zinc nitrate, sodium tetrafluoroborate or mixtures thereof. Suitable catalysts are also ammonium salts from the group of ammonium chloride, ammonium sulfate, ammonium oxalate, diammonium phosphate or mixtures thereof. Other suitable catalysts are organic or inorganic acids, for example maleic acid, formic acid, citric acid, tartaric acid, oxalic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, boric acid or mixtures thereof. Preferably, magnesium chloride, zinc chloride, magnesium sulfate, aluminum sulfate are used, more preferably magnesium chloride.

In a first variant of the treatment of lignocellulosic material, this is treated with a mixture of a fatty acid amide with formaldehyde and catalyst, in a second variant with a mixture of a fatty acid urea compound with formaldehyde and in a third variant with a mixture of melamine, formaldehyde, catalyst and fatty acid, fatty amine, fatty amide and / or fatty alcohol.

Instead of paraffin, which may generally have a melting point of about 40-80 ° C, especially 50-60 ° C, wax, ceresin, lanolin, Japan wax, Vaselineöle, artificial or natural resins and latex can be used, likewise in aqueous emulsion in combination with a zirconium and / or aluminum salt.

The mixtures according to the invention can be used instead of the aqueous mixture in a mixture with water or completely in organic solvent or supercritical CO ₂ for the treatment of lignocellulosic materials.

In the preferred embodiment, the lignocellulosic material, in particular wood, treated with the protective agent and / or its reaction components and then dried at temperatures up to 200 ° C.

In a further preferred embodiment, the protective agent in addition to fatty acid derivative as a reactive hydrocarbon derivative additionally contains unfunctionalized hydrocarbons in Mixture with aluminum and / or zirconium salts, for example paraffin, waxes or other hydrophobing agents.

To produce chipboards or WPCs according to the invention, the wood particles of these materials are likewise treated with the protective agent and then bonded in a known manner or introduced into a mixture with synthetic polymers. Subsequent to the hydrophobization of the wood particles for chipboard or WPCs, a coupling component may be added to the mixture with adhesive or synthetic polymer, preferably maleic anhydride, more preferably by reaction with maleic anhydride modified polypropylene (MAPP).

Particle boards made with wood particles treated with preservative show a higher resistance to moisture, or a lower water absorption and swelling, while the strength properties, in particular the tensile strength, are only insignificantly influenced. Also in comparison with chipboard whose wood particles were treated before bonding with paraffin alone instead of the protective agent according to the invention, the particle board or WPCs according to the invention have a higher resistance to moisture fluctuations, improved resistance to fungal attack and improved strength properties, in particular tensile strength.

Suitable protective colloids are, for example, glues, gelatin, cellulose ethers, e.g. Tylose, Cellapret, gums, mucilages, starch and dextrin, but preferably glue. Suitable emulsifiers include, inter alia, methoxylated or ethoxylated C 12 -C 20 -hydrocarbons, for example methoxylated or ethoxylated fatty acids, in particular ethoxylated stearic acid.

It is preferred that protective colloids or substances used as emulsifier do not form precipitates with the aluminum or zirconium salts. Further compounds which can be used as emulsifier are monoesters of higher molecular weight fatty acids with polyvalent alcohols, for example polyethoxylated vegetable oil (available under the name Emulphor), alkylphenol ethoxylates (available under the name Igepal), diglycol stearate or higher aliphatic or hydroaromatic alcohols. Furthermore, as emulsifier salts of higher molecular weight aliphatic and aromatic sulfonic acids, for example Suitable alkylnaphthalenesulfonic acids, as well as known under the name Lamepon A fatty acid (eg oleic acid) protein (eg collagen or oligopeptides from collagen) condensation product or the collagen surfactant Lamepon F.

• Figur 1 die Wasseraufnahme mit Schutzmittel auf Basis N-methylolierter Stearinsäure imprägnierten Buchenholzes bei einem Tauchtest zeigt,
• Figur 2 die Aufnahme von Schutzmittel auf Basis eines reaktiven Fettsäurederivats und den Masseverlust von A) Kiefernholzproben und B) Buchenholzproben zeigt, die mit erfindungsgemäßem Holzschutzmittel behandelt worden sind, im Anschluss an die Inkubation mit holzzerstörenden Pilzen über 16 Wochen,
• Figur 3 die Bewertung verschiedener Holzarten hinsichtlich ihres Befalls zeigt, die mit erfindungsgemäßem Schutzmittel auf Basis eines reaktiven Fettsäurederivats behandelt wurden und anschließend für 6 Wochen dem Bläuepilz Aureobasidium pullulans ausgesetzt worden,
• Figur 4 Fotografien von Holzproben, die mit erfindungsgemäßem Schutzmittel auf Basis eines reaktiven Fettsäurederivats bzw. Wasser (Kontrolle) behandelt waren, im Anschluss an die 6-wöchige Inkubation mit Aureobasidium pullulans entsprechend Figur 3 zeigt,
• Figur 5 Fotografien von Holzproben zeigt, die mit erfindungsgemäßem Schutzmittel auf Basis eines reaktiven Fettsäurederivats bzw. Wasser (Kontrolle) behandelt sind, vor und nach Schnellbewitterung (QUV).

The invention will now be described in more detail by way of example with reference to the accompanying drawings, in which:

• FIG. 1 shows the water absorption with protective agent based on N-methylolated stearic acid impregnated beech wood in a dip test,
• FIG. 2 shows the inclusion of protective agent based on a reactive fatty acid derivative and the mass loss of A) pine wood samples and B) beech wood samples treated with wood preservative according to the invention, following incubation with wood-destroying fungi over 16 weeks,
• FIG. 3 the assessment of various types of wood in terms of their infestation, which were treated with protective agent based on a reactive fatty acid derivative according to the invention and then exposed to the blue fungus Aureobasidium pullulans for 6 weeks,
• FIG. 4 Photographs of wood specimens treated with reactive fatty acid derivative-based (water) control agent according to the present invention following the 6-week incubation with Aureobasidium pullulans, respectively FIG. 3 shows,
• FIG. 5 Photographs of wood samples treated with protective agent of the invention based on a reactive fatty acid derivative or water (control) before and after rapid weathering (QUV).

Example 1: Preparation of a protective agent for lignocellulosic materials of fatty acid-substituted cationic N-methylol compounds

As the reactive fatty acid derivative, a fatty acid-substituted cationic N-methylol compound (melamine stearyl ether) having an addition of the Lewis acid aluminum sulfate of 0.3% by weight was used as a catalyst to obtain an aqueous composition having a concentration of 5% by weight.
As an example of lignocellulosic material, wood samples are dipped in the aqueous emulsion, with times of 1 to 48 hours producing satisfactory results. It is then dried and fixed at a temperature of 120 ° C in a drying oven. It can be shown that this leads to a reduction of the water absorption in the subsequent immersion test and a superficial hydrophobing is achieved.

Example 2: Reduction of water absorption of wood by impregnation with protective agent according to the invention

Beech wood samples measuring 5 × 10 × 30 mm (radial, tangential, longitudinal) were fully soaked in conventional vacuum pressure impregnation (120 mbar, 12 bar) with emulsions according to Example 1 within three hours. By heating from 40 ° C to 120 ° C over a period of 4 days in a drying oven, the preservatives are hardened and fixed in the wood. The reduction in water uptake was determined by immersing the impregnated beech wood samples in the immersion test for 96 hours followed by vacuum, each with different concentrations of the protective agent in the watering solution used in FIG. 1 are indicated. The water absorption in percent of the total weight is in FIG. 1 shown, the treated with water instead of protective agent suspension beech wood sample shows the highest water absorption as a comparison. The water absorption was determined by weight determination of the beech wood samples.

As an example of N-methylolated fatty acid stearic acid was used here. When impregnating beechwood samples with a fatty acid-substituted (stearic acid) cationic water-based N-methylol compound into the in FIG. 1 % by weight in aqueous composition was also demonstrated with a subsequent heat treatment at 40 ° C to 120 ° C for 4 days in a drying oven, a reduction in the water absorption capacity of the beech wood samples.

The results of the 96 hours immersion test with subsequent vacuum are in FIG. 1 shown and show that the water absorption with increasing content of Impregnating solution of inventive protective agent, the water absorption capacity of the lignocellulosic material decreases.

Example 3: Increasing the resistance of lignocellulosic material to wood-degrading fungi

Wood samples with the dimensions 5 × 10 × 30 mm (radial, tangential, longitudinal) were treated in an aqueous protective agent suspension according to Example 1, namely in vacuum pressure impregnation (120 mbar, 12 bar) for 3 hours with a 9 wt. % suspension saturated, then treated with increasing temperature of 40 ° C to 120 ° C for 4 days in a drying oven.

Subsequently, the wood samples were exposed to wood degrading fungi for 16 weeks. Beech wood specimens of a culture of Trametes versicolor (white rot) and pine wood specimens were exposed to a culture of Coniophora puteana (brown rot). The loss of mass, which could be determined after 16 weeks, is in FIG. 2 presented for A) impregnated pine wood after removal by Coniophora puteana and B) beechwood after removal by Trametes versicolor. The sample designated as a control was treated the same in each case, except that instead of the protective agent according to the invention alone water was used. The inscribed pillar in FIG. 2 A) and B) shows the weight gain of the respective wood samples after the vacuum pressure impregnation with subsequent heat treatment before the degradation test.

The results in FIG. 2 show with the example of pine wood of beech wood clearly that the degradation of the lignocellulosic material is greatly reduced by wood-destroying fungi when impregnated with the protective agent.

Example 4: Increasing the resistance to fungal fungi by protective agents

Platelets of various types of wood (40 × 40 × 5 mm) were treated by vacuum pressure impregnation (120 mbar, 12 bar) with an aqueous emulsion according to Example 1 with a content of 3 or 9% by weight of the protective agent. Subsequently, the plates were heat-treated at 40 ° C for 72 hours and at 120 ° C for 16 hours. In this heat treatment, water was first dried and carried out at higher temperatures, a reaction of the protective agent with the lignocellulosic material. Subsequently, the samples were conditioned after sterilization for about 2 weeks at 20 ° C and 65% relative humidity.

Subsequently, the platelets were placed in agar dishes colonized with Aureobasidium pullulans . A second inoculation of the platelets was done by placing a small round slice of agar, also colonized with Aureobasidium pullulans , on the top surface of the wood sample. Each agar dish contained two treated wood samples as well as two control samples which had been treated in parallel with water instead of the preservative. After an incubation period of 6 weeks, the infestation of the wood samples was evaluated on an arbitrary scale from 0 (no infestation) to 4 (heavily stained).

The result is in FIG. 3 represented for the different types of wood. It is clear that, with the exception of the pine wood sample, a higher concentration of the protective agent in the impregnating solution leads to a lower infestation of the lignocellulosic material by fungal fungi.

In FIG. 4 For example, photographs of the wood slides treated with a 9% by weight suspension of the preservative of Example 1 are shown after subsequent incubation with Aureobasidium pullulans over 6 weeks.

Example 5: Increase of the weathering resistance of lignocellulosic material

As an example of lignocellulosic material, pine wood samples were treated by vacuum pressure impregnation (120 mbar, 12 bar) with an aqueous emulsion according to Example 1 with 9 wt.% Protective agent. Thereafter, the samples were thermally treated at 40 ° C for 72 hours and at 120 ° C for 16 hours, whereby water was dried off and the protective agent reacted with the lignocellulosic material.

Subsequently, the wood samples as well as for comparison with water treated control samples were tested in the accelerated weathering device (Weathering Tester - Model QUV / Spray, Pausch Messtechnik GmbH, Haan, Germany).

The set weathering consisted of irradiation with UVA light (maximum absorption at 340 nm, 0.77 W / (m ² nm) with a fluorescence source over 48 cycles with 2.5 h UV radiation at 60 ° C and 30 minutes spraying with cold water (6 to 7 L / min) FIG. 5 are photographs of wood samples before and after rapid weathering, namely wood samples treated in the first line, control samples treated in parallel with water in the second row, where column A is the surfaces before weathering shows column B after 24 hours condensation with 24 subcycles (2.5 h QUV + 0.5 h spray), column C after 24 hours condensation + 30 subcycles (2.5 h QUV + 0.5 h spray), and Column D after 24 h condensation + 48 subcycles (2.5 h QUV + 0.5 h spray).

The photographs of FIG. 5 clearly show that lignocellulosic material obtains a higher weathering resistance by treatment with a protective agent according to the invention, as evidenced inter alia by the reduced cracking and the less graying (without added microorganisms).

Example 6: Chipboard

For the production of chipboard, topcoat and middle layer chips consisting of a mixture of 85% spruce and 15% beech were treated with 1) paraffin (melting point 50-60 ° C) with aluminum salt additive (hydrophobol APK),
2) fatty acid-modified melamine according to Example 1 in admixture with paraffin (1: 1) and
3) Alkyldiketendimer
each suspended to 3 wt .-% in aqueous emulsion.

For impregnation, the chips were kept in the emulsion in a vacuum oven for about one hour at a vacuum of about 40 mbar, then the impregnating emulsion was filtered under light vacuum and the chips in the oven for 12 hours at 60 ° C predryed, finally at 110 ° C dried for 2 hours. Reference plates were made from untreated chips for comparison.

The chips were made into V20-type chipboards having a desired thickness of 20 mm and a bulk density of 0.7 g / cm ³ . The glue used was urea-formaldehyde resin (UF resin Kaurit 350, BASF, Ludwigshafen), which has a dry matter content of 66.5 ± 1%, a pH of 7.5-9.5 at 20 ° C., a density of 1.28-1.3 g / cm ³ (20 ° C) and an ex works viscosity of 350 to 600 mPas.

For the gluing of the surface layer and middle layer chips, a motorized gluing drum with a volume of approx. 0.154 m ³ with belt drive was used.

The gluing was carried out with a loading gun (Walter Pilot) with a 1.0 mm nozzle.

For hot pressing, a one-level bottom piston press (Siempelkamp) with a maximum hydraulic working pressure of 283 bar was used. The plate-shaped press punches had a format of 600 x 800 x 80 mm and could be heated to 250 ° C.

The chip moisture of the chips used for plate production was below 5%, the desired moisture after gluing 12% for the top layer and 9% for the middle layer. The initial weight was about 850 g for the cover layer and 1300 g for the middle layer for the desired bulk density of 0.7 g / cm ³ .

Leim fleets were prepared by stirring with a stirrer (Jahnke and Kunkel, type RE162). The gluing in the gluing drum after the circulation process was carried out by spraying the glue through a nozzle projecting into the drum. The scattering was carried out by means of a scattering mold (300 x 500 mm) on a press plate, which was provided with non-stick paper. After sprinkling the top layer chips on the press plate, the middle layer chips were sprinkled, then the top layer of cover shavings. Before machine pressing, the chip cake had to be precompressed manually.

The sizing liquor had the following composition: Kaurit 350 to 10% by weight for top layer, 8.5% by weight for middle layer, ammonium sulfate to 0.5% by weight for top layer, to 1% by weight for middle layer. For pressing, a pressure of 220 bar at 195 ° C over 4 min was used.

After pressing, the chipboard was allowed to cure for 24 hours, trimmed to 300 mm x 500 mm, and ground to 19 mm with a grinder.
To test the water resistance, thickness swelling to EN 317 and transverse tensile strength to EN 319 were determined; the results are summarized in Table 1: <u> Table 1: Results Water resistance and strength of particle board </ u> control Chip treatment 1 Chip treatment 2 Chip treatment 3 Bulk density [g / cm ³ ] 711 685 723 696 Thickness swelling [%] after 24 h 20.4 6.7 7.3 9.5 Transverse tensile strength [N / mm ² ] 0.78 0.59 0.66 0.72

Example 7: Wood - Plastic Composites (WPCs)

Composites characterized by the content of the wood component in a preservative were prepared from spruce wood chips treated in accordance with the present invention and polypropylene.

500 g spruce wood chips (Lignocell P super, Rettenmaier company) were in each 5 L of a 0.3 wt .-%, 0.75 wt .-% or 1.5 wt .-% emulsion of a paraffin (melting point 52 to 54 ° C) with aluminum salt (comparison, test series P), alternatively with a fatty acid-modified melamine (according to the invention, series F) and shaken horizontally for 2 hours at room temperature, then filtered off.

The impregnated chips were dried for 72 hours at 25 ° C, 60 ° C and 103 ° C. Subsequently, the chips were conditioned at 20 ° C and 65% relative humidity to constant weight and then determined the weight. An aliquot was dried at 103 ° C and weighed to determine dry weight or moisture. For comparison, chips were treated only in water (control) instead of the protective agent.

The composite had a chip content of 60% with 40% polypropylene. First, a mechanical mixture of the treated (P or F) and untreated (control) spruce wood chips with polypropylene was obtained by mechanical mixing with granulated polypropylene (polypropylene-polyethylene copolymer, randomly distributed, melt flow index to ISO 1133 1.8 ± 0.4 g / 10 min at 230 ° C / 2.16 kg) in the rolling mill or roll mill and then pressed. On the rolling mill homogeneous rolling skins were prepared from the mixture of granulated polypropylene and the spruce chips at 180 ° C at a speed of 25 rev / min for 5 to 10 minutes, the then in the press (plate press "Schwabendan", type Polystat 400A) were first heated without pressure over 20 min to about 180 ° C and then pressed for 30 s at 10 bar. Cooling to room temperature was carried out at maintained pressure for 20 min in the press.

The mechanical properties were determined according to ISO 180 (notched impact strength), ISO 527-2 (tensile strength) and ISO 1183-1 (density). The water retention of the composite was determined by dipping the WPCs over 1 to 14 d compared to the control. The measured values are shown in Table 2 below. <u> Table 2: Mechanical properties and water retention in immersion testing of a spruce and polypropylene composite: </ u> P 0.3% P 0.75% P 1.5% F 0.3% F 0.75% F 1.5% control Notched impact strength [J] 4.23 3.98 4.12 3.95 3.86 3.72 4.07 Modulus of elasticity [N / mm ² ] 3689 3664 3640 3734 3691 3466 3721 Tensile strength [N / mm ² ] 25.3 24.2 22.7 24.1 25.5 23.4 25.8 Density [g / cm ³ ] 1.07 1.09 1.07 1.07 1.06 1.06 1.07 WA * 1 d 1.38 1.11 0.98 1.44 1.26 1.02 2.17 WA * 3 d 2.12 1.96 1.74 2.27 2.09 1.83 3.35 WA * 7 d 2.98 2.84 2.65 3.15 2.95 2.66 5.03 WA * 14 d 4.31 4.18 3.41 4.67 4.31 3.95 6.93 WA * means water absorption after 1, 3, 7 or 14 days (d)

The measured strength values show only insignificant changes compared to the control with untreated chips for both preservatives according to the invention, while the values of water retention show that this is markedly reduced by the protective agents according to the invention. Thus, the composite materials whose wood content has been treated with protective agent according to the invention, an improved resistance to moisture, especially against liquid water.

Claims (8)

1. Derived timber product of a mixture of wood in admixture with a synthetic material and/or adhesive, characterized in that the wood has a content of a C6 - C40 hydrocarbon which comprises N-methylol groups reactive with hydroxyl groups.
2. Derived timber product according to claim 1, characterized in that the synthetic material is selected from the group comprising polyethylene, polypropylene, polyethylene - polypropylene co-polymers.
3. Derived timber product according to claim 1 or 2, characterized in that the adhesive is selected from the group comprising urea - formaldehyde resin, phenyl - formaldehyde resin, melamine - formaldehyde resin, and isocyanate resin.
4. Derived timber product according to one of the preceding claims, characterized in that the derived timber product is a chipboard, OSB, or a timber - plastics - composite material (WPC).
5. Derived timber product according to one of the preceding claims, characterized in that the C6 - to C40 - hydrocarbon, which comprises N-methylol groups reactive with hydroxyl groups, is available by conversion of fatty acids and/or fatty acid amides and/or fatty alcohols with N-methylolated amino compounds.
6. Derived timber product according to one of the preceding claims, characterized in that the C6 - to C40 - hydrocarbon, which comprises N-methylol groups reactive with hydroxyl groups, has an addition of C1 - to C8 - diamino alkanes and/or urea.
7. Derived timber product according to one of the preceding claims, characterized in that the C6 - to C40 - hydrocarbon, which comprises N-methylol groups reactive with hydroxyl groups, comprises a catalyst, which is selected from the group comprising metal halogenids, metal sulfates, metal nitrates, metal tetrafluoro borates, metal phosphates and/or mixtures thereof, ammonium chloride, ammonium sulfate, ammonium oxalate, di-ammonium phosphate and their admixtures, maleic acid, formic acid, citric acid, tartaric acid, oxalic acid, p-toluenesulfonic acid, hydrochloric acid, sulfuric acid, and boric acid.
8. Derived timber product according to one of the preceding claims, characterized in that additionally, paraffins with emulsifier, detergent, or protective colloids are used in admixture with zircionium salt and/or aluminium salt in aqueous mixture.

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