Employment of polyisocyanates compositions as binders for composite lignocellulose materials

FIELD: composite materials.

SUBSTANCE: in particular, invention relates to employment of polyisocyanates compositions as binders for composites containing lignocellulose fibers such as oriented wood chipboard.

EFFECT: improved performance characteristics regarding detachment of product as compared to conventional polyisocyanates employed for binding lignocellulose material.

11 cl, 7 tbl, 8 ex

 

The technical field.

This invention relates to the use of polyisocyanate compositions suitable as a binder in obtaining composite lignocellulosic materials, particularly composites containing fiber lignocellulose, such as oriented particleboard. Polyisocyanate compositions of this invention contain specific, the polyisocyanate prepolymer, optionally mixed with a base polyisocyanate.

Background of the invention.

The use of organic polyisocyanates as a binder for lignocellulosic material in the manufacture of sheets or molded products such as waffle plate, chipboard, fibreboard and plywood, are well known and commercially desirable because of the resulting composites have high adhesive and cohesive strengths, their properties flexibly adapt to changes in the wood, they are universal in terms of the temperature and the speed of curing, the resulting composites have excellent structural properties and the ability to link lignocellulosic materials with a water content higher than normally used for polycondensation resins, such as phenol-formaldehyde resin.

However, p and using the standard isocyanate binders meet difficulties when processing high levels of moisture content in the composition, that may adversely affect the processing of composites. One method used for data difficulties to a minimum, is to use only lignocellulosic materials, the moisture content of which is low (i.e., with a moisture content in the range from approximately 3 to approximately 8%). This low moisture content in General is achieved by drying the original cellulosic feedstock to reduce the moisture content. However, the cost of such drying is high, and this has a significant impact on the economic parameters of the method. The use of materials with low moisture content is also disadvantageous, because the panels of the obtained composite material tends to absorb moisture and swell when used in wet environments.

Accordingly, there is a clear need for the creation of the polyisocyanate compositions of the binder that can be applied to the utilization of lignocellulosic raw materials with high moisture content, greatly reducing, thus, the total energy demand, going on drying in a production setting. At the same time, the polyisocyanate composition of the binder must provide composites having superior dimensional stability, when the product will be poked the th operation of pressing, and, thus, to a lesser extent undergoes shrinkage/return to equilibrium. The polyisocyanate composition of the binder should also allow to achieve higher stickiness of the Mat, thus ensuring the best stability of the Mat before pressing operation.

Another difficulty encountered in the extrusion of composite panels using conventional polymer diphenylmethanediisocyanate (pMDI), is that during the processing of the lower homologues in pMDI can leave the press together with excess steam at the stage of decompression. Accordingly, there is a need to ensure the feasibility of the method at lower pressures and shortened cycles pressing. Lower temperature extrusion results in a decrease in discharge at the stage decompression through the creation of a much lower gas pressure in the composite due to lower levels of presence of steam formed during extrusion at low temperatures or in shortened cycles pressing. Cutting cycles pressing provides the possibility of increasing the production capacity for existing installations without significant needs for investment in the new installation.

Reducing the number of required pressure during pressing while RA is the notes installation processing of the composite at higher levels of moisture content in the composition will result in reduce energy demand and potentially for those who would like to invest in new funds, to reduce the requirements to the pressure on the entire action of the press, which significantly reduces capital costs. Reduced requirements for hydraulic pressure to achieve the target thickness makes it possible for lignocellulosic composites at higher densities without the need for modification of existing equipment for pressing. In addition, the lower temperature extrusion and time cycles in the resulting product with a significantly reduced degree of degradation of the surface or charring arising from the use of external lubricants for forms, and therefore with excellent appearance, resulting in treatment after extrusion, such as grinding grinding skin will need less.

The isocyanate prepolymers are among the isocyanate materials that are used in the binder compositions for solving various problems of processing. For example, U.S. patent No. 4100328 describes prepolymers with terminal isocyanate groups, which improve tipanie finished product from the mold. U.S. patent No. 4609513 also describes a binder, which is a prepolymer with terminal isocyanate groups, improving tipanie the finished product. U.S. patent No. 5179143 picavet composition of the binder, in order to improve adhesion at room temperature is used the concrete type of the isocyanate prepolymer.

All of the above objectives have now been achieved and the benefits realized in the use of the polyisocyanate compositions of the present invention. This invention relates to the use of polyisocyanate compositions suitable as a binder in obtaining composite lignocellulosic materials, particularly composites containing fiber lignocellulose, such as oriented particleboard. Polyisocyanate compositions of this invention contain specific, the polyisocyanate prepolymer, optionally subjected to mixing.

Polyisocyanate compositions of the present invention allow to obtain a material whose properties can be adjusted in such a way as to achieve technological advantages/benefits in the properties of the final composite, required by the customer. The polyisocyanate prepolymer is obtained using hydroxyl-containing systems, introducing a prepolymer of communication that enhance the suitability of the final polyisocyanate compositions for binding lignocellulosic material. The composition of the present invention, thus, enables Alacati composites based on wood in a much more abbreviated cycles pressing compared with those that would have been possible even in the case of catalyzed isocyanate binder at lower temperatures and pressing pressures and at higher moisture content in the supply of lignocellulosic material in comparison with what would be possible during traditional processing of lignocellulosic composites. It was also found that the polyisocyanate composition of the present invention can achieve improved operational properties otlipaniya finished product in comparison with standard polyisocyanates, currently used for binding lignocellulosic material. Data improved performance properties are characterized by significantly lower levels of use of external lubricants for forms, such as wax or soap, to achieve the same operational properties otlipaniya finished product as standard polyisocyanate systems used in combination with significantly higher levels of loading the same external lubricants for forms. All of the above makes it obvious that the composition corresponding to the present invention, provide the manufacturer of composites based on lignocellulosic materials achieving several significant advantages.

Detailed description of the present invention.

The floor of the isocyanate composition according to the present invention, used for binding lignocellulosic material may contain a polyisocyanate prepolymer, and specified the prepolymer is a reaction product of MDI and polyol, wherein the content of free unreacted diisocyanate groups in the polyisocyanate composition is at least 8 wt.%. Preferably, at least 60%, more preferably from 70 to 86% of the content of free unreacted diisocyanate groups accounted for 4,4'-diphenylmethanediisocyanate.

The polyisocyanate composition of the binder is preferably characterized by the number of free NCO groups in the range from about 15 to about 30 wt.%, and more preferably from 20 to 30% wt. As described herein, it consists of a prepolymer with terminal isocyanate groups. This prepolymer is a reaction product of an excess of organic MDI and polyol.

The organic polyisocyanate which is used to obtain the prepolymer of the present invention, preferably is diphenylmethanediisocyanate (MDI), for example, 4,4'-MDI, 2,4'-MDI, polymeric MDI, MDI variants and mixtures thereof.

MDI is preferred to obtain the prepolymer is 4,4'-MDI or a mixture of 4,4'-MDI and 2,4'-MDI, where the mixture contains at least 50% 4,4'-MDI, preferably is in the quantity greater than about 75 wt.%, more preferably greater than about 90% wt. and most preferably greater than about 95% wt. Additionally, you can add "polymeric MDI". By "polymeric MDI" means polymethylenepolyphenylisocyanate contained in the polyisocyanate compositions, and functionality which are equal to at least a 2.5. Polymeric MDI is commercially available and is produced by postironium mixtures of polyamines obtained by condensation of aniline and formaldehyde in a suitable ratio. For the purposes of this invention particularly suitable polymeric MDI, the functionality of which is in the range of 2.5-3.5, and preferably 2,5-3,1.

The polyol used to obtain, contain from 2 to 8 hydroxyl groups. The preferred polyols are polyester polyols. The term "polyester polyol", in turn, could mean a mixture of these different products, subjected to alkoxycarbonyl. Preferred polyols include those compounds in which there are depolimerizovannogo parts of propylene oxide and/or depolimerizovannogo units of ethylene oxide. These links can be combined with a statistical distribution in the form polietilenoksidnoy blocks within the chain and/or ends.

In highly preferred polyester p is Lily, suitable for the production of the prepolymer with terminal isocyanate groups contain at least about 15 wt.%. ethyleneoxide groups, and more preferably from 50 to 100 wt.%. ethyleneoxide groups. Polyester polyols are different average nominal functionality in the range of 2-6, and preferably 2-4. Their srednekislye equivalent weight is from about 700 to about 5000, the preferred equivalent weight is from about 1000 to about 4000, more preferably from about 1200 to about 3500, and most preferably from about 1500 to about 3000.

Polyester polyols to be used in obtaining prepolymer with terminal isocyanate groups include products obtained by polymerization of ethylene oxide with other cyclic oxide, for example propylene oxide, in the presence of polyfunctional initiators; however, this product must meet the requirements described earlier in this description. Suitable connections initiators contain several active hydrogen atoms and include water and low molecular weight polyols, for example ethylene glycol, propylene glycol, diethylene glycol, dipropyleneglycol, cyclohexanedimethanol, resorcinol, bisphenol a, glycerol, trimethylolpropane, 1,2,6-GE is Cantril, the pentaerythritol and the like. You can use a mixture of initiators and/or cyclic oxides.

Particularly suitable polyester polyols include poly(oxyethylenenitrilo)diols and/or trioli obtained in the step of joining propylene and ethylenoxide to bi - or trifunctional initiators as fully described in the prior art. Also suitable mixtures of these diols and triolo, the most preferred diols.

A prepolymer with terminal isocyanate groups produced by the reaction between excess amount of MDI and polyether polyol. The number of MDI and polyether polyol, known as effective in obtaining prepolymer having the specified number of NCO groups, using methods known in the art. For example, the prepolymer can be obtained by the reaction of organic MDI and polyether polyol with subsequent dilution of the modified polyisocyanate defined herein, in the case of the latter. Alternatively, the modified polyisocyanate can be mixed with unmodified polyisocyanate prior to the reaction with the polyol. Such reactions give the opportunity to proceed at temperatures effective to receive the prepolymer, such as in the range of from about 40°With up to approximately 100°and in General the use of a catalyst is optional. The relative amounts of organic MDI and polyol depend on the desired number of NCO groups of the prepolymer, the number of NCO groups of the MDI and the number HE polyol, and they will easily be able to calculate a specialist in this field.

At least 90% of the groups resulting from the reaction of MDI and polyether polyol in the process of synthesizing the prepolymer are urethane groups. To thus obtained the prepolymers can be added to the polyisocyanate or its variant with the proviso that the number of NCO groups will remain in the specified range described above in this description. The base polyisocyanate or an option can be selected from the compounds listed above. Preferred aromatic polyisocyanates and particularly polyisocyanates based on MDI. Even more preferably, the addition of modified MDI and even more preferably, the base polyisocyanate was the version of the MDI used to carry out the reaction with the polyol.

The base polyisocyanate.

The polyisocyanates intended for use as a basic MDI, can be any organic derivative MDI or a mixture of organic deposition is different MDI provided these compounds contain at least 2 isocyanate groups. Organic polyisocyanates include diisocyanates, in particular aromatic diisocyanates, and isocyanates of higher functionality. Examples of organic polyisocyanates which can be used in the compositions of the present invention include aliphatic isocyanates such as hexamethylenediisocyanate; and aromatic isocyanates such as m - and p-delete the entry, toluylene-2,4 - and toluylene-2,6-diisocyanate, difenilmetana-4,4'-diisocyanate, chlorphenesin-2,4-diisocyanate, naftilan-1,5-diisocyanate, diphenylene-4,4'-diisocyanate, 3,3'-dimethyldiphenyl-4,4'-diisocyanate, 3-methyldiphenylamine-4,4'-diisocyanate diisocyanate and simple diphenyl ether; and cycloaliphatic diisocyanates such as cyclohexane-2,4 - and -2,3-diisocyanate, 1-methylcyclohexyl-2,4 - and -2,6-diisocyanate and mixtures thereof, and bis(isocyanatophenyl)methane, and triisocyanate, such as 2,4,6-triisocyanate and simple 2,4,4'-triisocyanate ether. Also can be used and modified polyisocyanates containing which, carbodiimide or uretonimine group. In addition, you can use the blocked polyisocyanates, such reaction product of phenol or oxime and MDI, the temperature of the release of which is below the temperature when using the polyisocyanate composition. You can use a mixture of isocyanates, for example, a mixture of isomers tolylenediisocyanate, such as commercially available mixtures of 2,4 - and 2,6-isomers and a mixture of bifunctional polyisocyanates and polyisocyanates of higher functionality, the resulting vosganian the condensation products of aniline/formaldehyde. Such mixtures are well known in the art and include not subjected to further processing after receiving the products vosganian containing polyphenylalanine with methylene bridging groups, including diisocyanate, triisocyanate and polyisocyanates of higher functionality, together with any by-products of vosganian. Preferred isocyanates for use in the present invention are isocyanate, which is an aromatic diisocyanate or polyisocyanate of higher functionality, such as the net diphenylmethanediisocyanate or a mixture of polyphenylalanine with methylene bridging groups containing diisocyanates, triisocyanate and polyisocyanates of higher functionality. Polyphenylalanine with methylene bridging groups are well known in the art. They are postironium appropriate mixtures of polyamines, which are the result of what ondensate of aniline and formaldehyde. For convenience, the polymer mixture of polyphenylalanine with methylene bridging groups containing diisocyanate, triisocyanate and polyisocyanates of higher functionality later in this description referred to as polymeric MDI. Suitable polyisocyanates include SUPRASEC™ DNR, SUPRASEC™ 2185, RUBINATE™ M and RUBINATE™ 1840, all manufactured by Huntsman Polyurethanes. The polyisocyanate preferably is a liquid at room temperature. Polyisocyanate mixture can be obtained in accordance with any of the techniques known in the art. If necessary, the content of isomers diphenylmethanediisocyanate can be brought to the required ranges, using techniques that are well known in the art.

In order to further improve or stability during storage polyisocyanate composition of the present invention, or cost effectiveness in the present invention, the composition can be added to the diluent. Suitable diluents include plasticizers of the type described in "Taschenbuch der Kunststoff-Additive", Ed. by R. Gachter and H. Muller, Carl Hanser Verlag Munchen, third edition, 1989. Preferred diluents are phthalates, aliphatic carboxylates, esters of fatty acids, linseed oil, soybean oil, and propylene carbonate. These add thinners in quantities, the composition is shining from 1 to 40 mass parts per 100 mass parts of MDI, and preferably in quantities of from 1 to 15 mass parts per 100 mass parts of MDI. The composition may further contain commonly used additives such as flame retardants, preservatives for lignocellulose, fungicides, waxes, sizing tools, fillers, surfactants, thixotropic additives, and other binders, such binder based on formaldehydefree polycondensation resins and lignin (optional in combination with lignin solvent, such as described in patent application PCT No. ER/00924). Particularly preferred additive for use in the polyisocyanate composition of the present invention is a binding agent, such as organo-functional silane (for example, Dynasylan AMEO, purchased the company Huls). Adding a polyisocyanate composition such agent binding allows to achieve improved properties of manufactured boards. The binding agents on the basis of organo-functional silane is used in amounts comprising from 0.01 to 3%, preferably from 0.1 to 2% wt. based on the polyisocyanate. Polyisocyanate composition of the present invention can be obtained by simple mixing of the ingredients at room temperature before applying the MDI on the lignocellulosic material.

Specific prepolymer on the Snov certain mixture of isomers, relevant to the present invention, receive as a result of the introduction of the first hydroxyl-containing substances to enter the link corresponding to the type of the prepolymer. This operation is carried out under vigorous stirring with or without the use of heat depending on the nature of substances and usually this operation is carried out in an inert atmosphere (nitrogen or dry air). Then the final polyisocyanate system designed for use as a binder for lignocellulosic material is obtained by introducing the required quantity of prepolymer defined in this invention, in another polyisocyanate defined by this invention. This can be achieved with or without the use of included in the processing line of mixing equipment, or any other methods known to the person skilled in the art. The final polyisocyanate composition is then applied to the lignocellulosic material with or without added compounds-solvents and/or with or without the use of heat to reduce the viscosity of the material before application. Then, as a result of the use of pressure and temperature for a certain period of time the material utverjdayut to obtain the final composite material.

Describes the e lignocellulosic material.

Lignocellulosic materials, which can bind the polyisocyanate prepolymer of the present invention include: wood, bark, cork, sugar cane bagasse, straw, flax, bamboo, Esparto, skin rice grains, fiber sisal, coconut fiber, wood chips, wood fiber, wood chips, wood dust, wood flour, hemp, nut shell, the husk of the grains of cereals, such as rice and oats. Particularly preferred wood, straw and squeezed sugar cane. To obtain a composite material containing polyisocyanate of the present invention, it is possible to use any mixture of the above materials. In addition, lignocellulosic materials can be mixed and other materials in the form of particles or fibers, such as chopped thrown in the waste foams (for example, crushed thrown in the waste polyurethane foam, mineral fillers, glass fiber, mica, rubber, thrown in the waste textiles, such as fiber and fabric of plastic. These materials can be used in the form of pellets, shavings or chips, fibers, fibers, spheres or powder. The moisture content of these materials may be in the range from 2% to 50%, preferably from about 5% to 20%, and most preferably from 8% to 20%. When applying the polyisocyanate compositions of this is bretania on lignocellulosic material mass ratio of the polyisocyanate/lignocellulosic material will vary depending on the bulk density used lignocellulosic material. So polyisocyanate compositions can be applied in such quantities as to obtain the mass ratio of the polyisocyanate/lignocellulosic material in the range from 0.1:to 99.9 to 20:80, preferably in the range of from 0.5:of 99.5 to 10:90, and most preferably in the range of from 3:97 to 8:92. If desired, in combination with the polyisocyanate composition of the present invention can be used, and other commonly used binders such as binder based on formaldehydefree polycondensation resins.

The composition of the present invention optionally may contain commonly used additives such as lubricants for forms, such as waxes, catalysts, flame retardants, stabilizers for lignocellulose, fillers, surface-active substances.

Description method of producing lignocellulosic composites.

1. Getting lignocellulosic material.

In the method of the present invention obtained lignocellulosic material is first dried to the desired moisture content. Since the moisture content required when using aromatic MDI of the present invention, is significantly higher in any apparatus for drying requires a much smaller amount of time, resulting in a significant increase in performance installation for drying in status the ve unit for production of a composite. In addition, higher levels of moisture, which is valid for the polyisocyanates of the present invention, means that there will be significantly reduced volatile organic compounds from drying normal production installation.

2. The coating composition polyisocyanate binder for lignocellulosic material.

In the method of the present invention the polyisocyanate composition of the binder add to intended for binding lignocellulosic material in an amount constituting from 1 to about 20% (mass.) the total weight of binder plus lignocellulosic material, preferably from 2 to about 10% wt.

3. Prior mats/pre-forms.

The resulting mixture of the lignocellulosic material and MDI can then be molded from obtaining "preliminary mats" for the manufacture of panels or obtaining any other required forms. The use of MDI of the present invention can be used to increase the level of "stickiness", thus making possible a more efficient delivery of finished products by improving consistency Mat/form as a complete system prior to pressing. As a result, it can reduce the level of losses due to the poor distribution of lignier the vines.

4. Pressing pre-Mat/pre-forms.

Under the action of heat and pressure can then extruding pre-Mat/preliminary form to get the panels or three-dimensional molded product with the attached form. Suitable for a method of pressing temperature in the General range from approximately 70 to approximately 250°C, preferably from about 130 to about 205°and most preferably from 140 to 180°C. the Pressure used in the methods of pressing to obtain the required dimensions of the product are in the range of from about 50 to about 300 bar, which is much lower than the pressures required for normal receipt of the composite. Needless to say, the pressing time will depend on thickness of the obtained product. In the use of the polyisocyanate compositions of the present invention, it was found that the need to use methods with steam injection is absent, even for composites with thickness exceeding 25 mm in a Similar way of veneer, paper or woven materials can be obtained laminate or molded products as a result of processing layers of a binder as described above, then pressing in the General case, at elevated temp is the temperature and pressure. In such methods, in General, the preferred temperature, directly affecting the surface of the composite in the range from 100 to 240°With the most preferred temperature in the range from about 140 to 220°C. To ensure composites with desired dimensional stability and physical characteristics when using the polyisocyanate composition of the present invention, the temperature to which exposed the core of the composite can be in the range from 70 to 140°With a preferred temperature of from 80 to 130°and the most preferred temperature from 85 to 120°C. the Initial pressure is preferably in the range from approximately 50 to 300 bar, while most preferably the initial pressure in the range from 50 to 200 bar. In addition, the polyisocyanate composition of the present invention are extremely effective in terms of minimizing the undesirable adhesion to the pillows of the press, the press plates, embossed plates of the press and other surfaces with which the treated lignocellulosic material may come into contact when used in combination with systems external lubricants for forms.

5. The product after extrusion/final product.

HDMI is fair products based on wood, obtained by using the binder of the present invention, an excellent appearance due to the considerably lower temperature extrusion in combination with reduced times of the loops, allowing you to achieve a much lower level of degradation of the surface or charring external lubricants for forms. In addition, receive excellent properties internal linking, good dimensional stability and excellent durability appearance of the resulting materials, and thus they can be used in any situation in which typically use such products.

In prior art accessible and more detailed descriptions of methods of obtaining products on the basis of the lignocellulosic material. Techniques and equipment commonly used, can be adapted for use for the polyisocyanate compositions of the present invention.

The invention is illustrated but not limited by the following examples:

Example 1.

A prepolymer was obtained by reaction between 83,7 mass parts Suprasec DNR (standard polymeric MDI) and 16.3 mass parts Volpo G26, glycerine initiated polyether polyol, terpolymerization with 100% ethylene oxide (EO) until then, until reaching the MM, 1200 (HE=140 mg KOH/g). The response time was R the VNO of 1.5 hours in an oven at 85 aboutWith air circulation. The resulting product according to the dimension was characterized by a content of NCO groups, equal to 24%, and contained 23.1% of free unreacted MDI, in which 93,9% 4,4'-MDI. Then the prepolymer, was applied by spraying in the mixer with a rotating drum on pine wood shavings containing 25% N2On (based on dry weight). The binder concentration was 6% (based on dry wood. After molding Mat extruded panel of oriented particle Board with dimensions of 400 mm x 400 mm x 14 mm and a density of 650 kg/m3. The temperature of the press plates was equal to 150aboutWith the odds pressing was 11 sec/mm, while the stage of pressing and degassing took 20 seconds. The strength of internal linking panel in the dry state (V20-IB) was equal 673 kPa, and swelling after 24 hours was 9.1%.

The NCO content in the prepolymer (%)24
Type polyolGlycerol + SW
MM1200
The concentration of binder (%)6
The density of the panel (kg/m3)650
Panel thickness (mm)14
The moisture content of wood (%) 25
Temperature pressing (aboutC)150
The coefficient pressing (s/mm)11
The strength of internal linking V20-IB (kPa)673
Swelling after 24 hours (%)9,1

Example 2.

Used the same binder as described in example 1 under similar conditions, but when the temperature of the press plates, 100°and a higher value of the coefficient of compression is 17 sec/mm Strength internal linking in the dry state was equal to 412 kPa, and swelling after 24 hours was 10%.

Example 3.

A prepolymer was obtained, using a technique similar to example 1, using standard polymeric MDI and PEG 600, glycerine initiated polyether polyol, terpolymerization with 100% ethylene oxide (EO) until then, until reaching the MM, 600 (the number HE=140 mg KOH/g). The reaction time was equal to 1.5 hours in an oven at 85aboutWith air circulation. The resulting product according to the dimension was characterized by a content of NCO groups, equal to 28%, and contained 32.8 per cent free of unreacted MDI, which was 94.2% 4,4'-MDI. Mats of wood chips for the oriented particle Board coated with this product, applied as in CA is re 1, it was possible to process at a temperature of extrusion 130aboutWith, the coefficient pressing 17 sec/mm and a moisture content of 25%.

Example 4.

A prepolymer was obtained, using a technique similar to example 1, using standard polymeric MDI and PEG 600, glycerine initiated polyether polyol, terpolymerization with 100% ethylene oxide (EO) until then, until reaching the MM, 600 (the number HE=140 mg KOH/g). The reaction time was equal to 1.5 hours in an oven at 85aboutWith air circulation. The resulting product according to the dimension was characterized by a content of NCO groups, equal to 22%, and contained 15.2% of free unreacted MDI, in which 94,1% 4,4'-MDI. Mats of wood chips for the oriented particle Board coated in the form of this product, applied as in example 1, was treated at the temperature of extrusion 130aboutWith, the coefficient pressing 17 sec/mm and a moisture content of 25%.

Example 5.

The prepolymer of PEG 600 and standard polymeric MDI was obtained analogously to example 1. The resulting product according to the dimension was characterized by an NCO content equal to 20%, and contained 10% of free unreacted MDI, in which 93,5% 4,4'-MDI. Panel oriented particle Board can be obtained from chips, containing the 25% moisture, with the application by means of spraying the binder concentration equal to 6%, at the temperature of the press plates 190aboutAnd the coefficient pressing 5.3 seconds/mm

The NCO content in the prepolymer (%)20
Type polyolGlycol + SW
MM600
The concentration of binder (%)6
The density of the panel (kg/m3)550
Panel thickness (mm)14
The moisture content of wood (%)25
Temperature pressing (aboutC)190
The minimum coefficient of pressing (s/mm)5,3
The strength of internal linking V20-IB (kPa)494
Swelling after 24 hours (%)8,4

Example 6.

A prepolymer with 8% NCO was obtained from 4,4'-isomer Monomeric MDI and polyether polyol Arcol 2580. The latter is represented by a compound derived from glycerol and EO/PO with the statistical distribution of 75% SW and MM, equal 4007. This prepolymer is then mixed with Suprasec DNR to obtain a material with a NCO content equal to 25%. This product contained 32.8 per cent free of unreacted MDI, in which 94.5% of his who ilos on 4,4'-MDI. This product using spray was applied to the wood chips and processing of data was performed by the method similar to example 5, except that the moisture content was lower at 18%. Reached the same minimum coefficient pressing, as in the previous example: 5.3 seconds/mm

The NCO content in the prepolymer (%)25
Type polyolGlycerol+EO/PO (75/25)
MM4007
The concentration of binder (%)6
The density of the panel (kg/m3)615
Panel thickness (mm)14
The moisture content of wood (%)18
Temperature pressing (aboutC)190
The minimum coefficient of pressing5,3
(sec/mm)
The strength of internal linking V20-IB(kPa)561
Swelling after 24 hours (%)7,8

Example 7.

Conducted a comparison between the prepolymer described in example 6 (=PP1), and standard polymeric MDI, not included in the scope of the present invention, but is usually used to obtain composite panels (=PP2). Appropriate tie the matter with a concentration of 6% per wood was applied by spraying and received panel 400 mm x 400 mm x 14 mm with a density of 650 kg/m 3. Registered coefficients pressing to separation at a temperature of 100°for forprimary system (PP1) and the temperature of the pressing 190°With standard MDI (PP2). When using the prepolymer of the present invention, based on 75% of SW (PP1) composites can be obtained in a close ratios pressing, but at temperatures that were 90°lower compared to those that are required for standard MDI.

The minimum achievable coefficient pressing (s/mm)
Content

moisture (%)*
Temperature pressing (°)PP1PP2
1510013
1519010
2510014
2519012

Recorded and maximum hydraulic pressure laboratory press Siempelkamp for pressing mats (400 mm x 400 mm x ± 150 mm) to the target thickness is 14 mm, when using a binder PP1. At higher levels of moisture content in Yerba mate (25%) required the th for the compaction energy was reduced by ± 100% compared to a lower level of moisture content in the material (15%).

MC (moisture content) (%)*Temperature pressing (aboutC)Maximum hydraulic pressure (bar)
15100130
2510065
* Calculated on dry wood. The measured values in the calculation of the mixture represent 12% and 19%, respectively.

The results demonstrate the significant effect of the availability to handle panel with a higher level of moisture content on demand in the hydraulic pressure required to achieve the final thickness of the Mat. While obtaining panels containing composition of the present invention, at the end of the pressing cycle recorded and the maximum temperature of the core, which is provided in the panel. Registration was performed using a temperature probe connected to the software ATR press Siempelkamp. In panels obtained when the temperature of the press plates 100aboutWith, directly prior to decompression in the core was achieved max 90aboutC.

MC (moisture content) (%)*Temperature press the s ( aboutC)The maximum temperature of the core (aboutC)
1510090
2510090
* Calculated on dry wood. The measured values in the calculation of the mixture represent 12% and 19%, respectively.

The results demonstrate that the composition of the present invention makes it possible to obtain composites, in which the internal temperature does not reach 100°S. It's amazing for any expert in the field of composites, where the maximum temperature of the core to decompression above 100°it is considered a necessary condition for obtaining composites with suitable performance characteristics.

Example 8.

A prepolymer was obtained and processed in accordance with the conditions of example 5. On steel press plates were made 15%aqueous solution of potassium oleate at a concentration of 4 g/m2. Quality operating properties otlipaniya finished product after pressing numbered in a scale from 0 to 5, where the latter value was a complete lack of adhesion to the plates. Category 5 was consistently made seven panels, after which the experiment was stopped.

Sample The bottom plateTop plate
The number of times
155
255
355
455
555
655
755

Category regarding otlipaniya finished product was assigned as values in the range from 1 to 5, have the following meanings:

1 - full adhesion, the plate material cannot be removed without destruction of the plate material.

2 - stick with the destruction of timber in excess of 50%.

3 - stick with the destruction of the wood, less 25%, but a large 5%.

4 - stick with the destruction of the wood, less 5%. Removal of plate material requires little effort.

4, 5 - adhesion without destroying the wood, kept the plate material. Removal of plate material effort is not required.

5 - excellent tipanie finished product plate material otlipat spontaneously.

1. Polyisocyanate composition used for binding lignocellulosic materials containing a polyisocyanate prepolymer, where the decree is hydrated prepolymer is a reaction product of MDI and polyol carried out at elevated temperature such as a temperature in the range from 40 to 100°C, optionally in the presence of a catalyst, and where the content of free unreacted diisocyanate polyisocyanate in the composition is at least 8 wt.%, and, at least 60% of the content of free unreacted diisocyanate accounted for 4,4'-diphenylmethanediisocyanate.

2. Polyisocyanate composition according to claim 1, where from 70 to 86% of the content of free unreacted diisocyanate accounted for 4,4'-diphenylmethanediisocyanate.

3. Polyisocyanate composition according to claims 1 and 2, where the polyol is a polyester polyol containing from 2 to 8 hydroxyl groups, where the polyester polyol contains depolimerizovannogo alkylene links, including at least 15% ethylenoxide links.

4. Polyisocyanate composition according to claims 1-3, where this polyisocyanate composition further comprises polyvinylpolypyrrolidone.

5. Polyisocyanate composition according to claims 1-4, where the NCO content in full polyisocyanate composition is from 20 to approximately 30%.

6. The method of binding lignocellulosic material, comprising the stages of (a) bringing the lignocellulosic material in contact with the polyisocyanate composition according to claims 1-5, (b) if necessary, drawing paper pokr is ment directly on the surface of the Mat or lubrication for forms-based wax or metal-containing solution of soap on the surface of the lignocellulosic composite or metal plates equipment for pressing before application of pressure to the surface of the Mat in the equipment for pressing, c) then create the conditions specified material for the flow binding.

7. The method according to claim 6, in which the polyisocyanate composition according to claims 1 to 5 is brought into contact with the lignocellulosic material and the thus obtained combination is subjected to hot pressing between metal plates at a temperature in the range from 100 to 250°and the typical pressure in the range from 1 to 8 MPa to obtain a composite material with a density of from 500 to 900 kg/m3.

8. The method according to claim 7, in which the polyisocyanate composition according to claims 1 to 5 is brought into contact with the lignocellulosic material and the thus obtained combination is subjected to hot pressing between metal plates at a temperature in the range from 150 to 200°and the typical pressure in the range from 2 to 6 MPa to obtain a composite material with a density of from 590 to 750 kg/m3.

9. The method according to claim 6, in which the polyisocyanate composition according to claims 1 to 5 is brought into contact with the lignocellulosic material and the thus obtained combination is subjected to hot pressing between metal plates at a temperature in the range from 100 to 250°and the typical pressure in the range from 1 to 8 MPa, where the measured temperature of the core of the composite during pressing is in the range from 80 to 130° C.

10. The method according to claim 6, where the specified combination is subjected to hot pressing.

11. The method according to PP-10, in which the polyisocyanate composition is applied in such quantity to obtain the mass ratio of polyisocyanate composition to the lignocellulosic material in the range from 0.1:to 99.9 to 20:80.



 

Same patents:

FIELD: polymer materials.

SUBSTANCE: invention relates to polyurethane-polyol compositions comprising product of reaction of a polyol and Herbert alcohol, the two containing In average 12 carbon atoms. Preferred polyols are α,β-diols and α,β-diols. Polyurethane-polyol compositions exhibit very low viscosity and are particularly suitable in coating compositions with very low content of volatile organics. Hardened coating obtained from claimed compositions ensure high resistance to cracking and can be applied on various substrates such as metal, plastic, wood, glass, ceramics.

EFFECT: increased strength of coatings on a variety of substrates.

5 cl, 3 tbl

FIELD: coating compositions.

SUBSTANCE: invention relates to composition used for coating applying and comprising polyisocyanate compound, hydroxyl-functional film-forming polymer and nonvolatile branched monoatomic alcohol wherein the aliphatic branched monoatomic alcohol is preferable but long-chain nonvolatile branched monoatomic alcohols are more preferable. This provides preparing compositions for applying coatings that possess the improved indices of fluidity and can be used for preparing coatings with the improved appearance and without the negative effect on other properties. Also, invention relates to the multiple composition fir applying coatings. The multicomponent composition for applying coatings represents the bicomponent composition for applying coatings preferably that comprises the polyisocyanate component in addition to hydroxyl-functional film-forming polymer comprising nonvolatile branched monoatomic alcohol also. Also, invention relates to a method for car finishing comprising applying compositions for applying coating on car and to a method for preparing the multilayer coating.

EFFECT: valuable properties of composition.

30 cl, 1 tbl, 2 ex

FIELD: chemistry of polymers.

SUBSTANCE: invention relates to aromatic polyurethane polyols used as components of priming compositions. Invention describes the priming composition comprising aromatic polyurethane polyol including product of reaction: (a) at least one diol component among number of α,β-diols, α,γ-diols and their mixtures; (b) at least one triisocyanate; (c) at least one diisocyanate wherein at least one isocyanate is aromatic one, and molecular mass or aromatic polyurethane polyol is 3000 Da, not above, and a cross-linking agent also. Prepared aromatic polyurethane polyol shows viscosity value by Brookfield at the level 8260 centipoises, OH-number 192.6 KOH/g and the dispersity (Mn/Mw) at the level 3.0. Priming compositions prepared by using indicated aromatic polyurethane polyol are useful in finishing large means of transportation, for example, trains, trucks, buses and airplanes, in particular, in vehicle body works. Also, invention relates methods for applying priming compositions on support comprising applying indicated compositions, and to a method for finishing car in repairs comprising applying the indicated priming composition.

EFFECT: improved and valuable properties of composition.

11 cl, 5 tbl, 12 ex

FIELD: protective coatings.

SUBSTANCE: invention relates to a method for applying onto wood substrate coating with increased resistance to effects of chemical products. Method comprises following stages: (i) addition, to aqueous polyatomic alcohol suspension, of composition based on isocyanate(s) and anionic surfactant having hydrophilic portion containing anionic group and lipophilic portion containing hydrocarbon radical, isocyanate(s)-based composition containing no more than 30% surfactant bound to isocyanate group, to form aqueous emulsion of isocyanate(s) and surfactant; (ii) applying resulting mixture onto wood surface of substrate; and (iii) aging to complete reaction of isocyanate(s) with polyatomic alcohol required to form polyurethane coating.

EFFECT: increased strength of coating (at a level of 90 units) and acquired resistance to a variety of chemical, cosmetic, and woof products according to corresponding standard.

18 cl, 4 dwg, 5 ex

FIELD: protective coatings.

SUBSTANCE: invention relates to methods for protecting metallic surfaces of geophysical instruments for exploring wells against combined action of generated acoustic field, drilling mud components, and formation fluids causing rapid wear of well instrument body. Gluing of protective polyurethane coating to cleaned and degreased metallic surface is effected by a way wherein glue composition based on triphenylmethanetriisocyanate in organic solvent is preliminarily applied onto surface as a layer with thickness 0.5-5 μm, preferably 1-3 μm, after which applied film is aged for 15-30 min at 100°C or for 12-18 h at 20-25°C and relative air humidity 30 to 98% and then protective coating based on lacquer polyurethane and/or poured polyurethane composition is deposited and hardened by a known method.

EFFECT: improved quality of received acoustic signal.

4 cl, 1 tbl, 3 ex

FIELD: building materials.

SUBSTANCE: invention relates to polyisocyanate compositions used for impregnation of concrete construction surfaces for aims of their anti-corrosive protection, and to a method for concrete impregnating by using the indicated composition. The claimed composition comprises earth-alkali metal salt dissolvable in polyisocyanate taken in the amount 0.1-5 mas. p. p. per 100 mas. p. p. of polyisocyanate. Except for, the composition can comprise additionally a hydrophobic solvent and a hydrophobic plasticizer. The claimed composition provides the deep penetration of impregnation up to 9.5 mm. The composition can be used in impregnation of brick masonry, sandy-cement covering for floors, in reconstruction of reservoirs for liquids storage and ferroconcrete constructions.

EFFECT: improved and valuable properties of composition.

6 cl, 1 tbl, 27 ex

FIELD: protective coatings.

SUBSTANCE: invention provides coating composition comprising first compound containing at least one bicyclo-ortho-ester functional group, second compound containing at least two isocyanate groups, and third compound containing at least one thiol group.

EFFECT: enlarged assortment of coatings.

19 cl, 10 tbl, 30 ex

FIELD: polymer production.

SUBSTANCE: coating composition comprising at least one compound with at least two isocyanate functional groups; at least one compound reactive to isocyanate and having at least two groups reactive to isocyanate groups, which are selected from mercapto groups, hydroxyl groups and combinations thereof; and cocatalyst consisting of phosphine and Michael acceptor, amount of catalyst constituting from 0.05 to 20% of the weight of dry residue. Invention also describes a method for coating substance with indicated composition as well as coated substrate, and adhesive containing at least one compound with at least two isocyanate functional groups and at least one compound containing at least two above defined groups reactive to isocyanate groups. Moreover, invention discloses employment of composition for finishing of great vehicles and refinishing of motor cars. Composition is characterized by drying time at a level of 20 min, modulus of elasticity 1904, Persose hardness 303, and brightness (85°C) at a level of 100.

EFFECT: expanded coating assortment.

16 cl, 16 tbl, 48 ex

FIELD: protective coatings.

SUBSTANCE: invention relates to composition to form coatings with quick-setting surface at ambient temperature for use in re-finishing industry, in manufacture of clear coating, and as primer layer in multilayer coating. Composition contains at least one latent base-type photoactivator and base-catalyzed polymerizable or hardenable organic material including isocyanate-reactive groups bearing at least one thiol group.

EFFECT: enabled preparation of compositions, which can be UV hardened and are characterized by acceptable setting velocity at ambient temperature in locations not easily accessible for UV emission.

15 cl, 11 tbl, 10 ex

Polymer composition // 2263695

FIELD: polymerizing mixtures for making water-repellent and anticorrosive coats.

SUBSTANCE: proposed polymer composition contains polyester resins, styrene, hardening agent-peroxide compounds and accelerating agent, inert substances, gel-type binder, paraffins and poly-urethanes. Proposed composition increases service life of coat due to reduction of effect of aggressive factors of outside medium on characteristics of coat.

EFFECT: increased rate of polymerization without considerable stresses in coat; facilitated procedure of applying coats on base of this composition.

23 cl, 80 ex

FIELD: polymer materials.

SUBSTANCE: invention relates to polyurethane-polyol compositions comprising product of reaction of a polyol and Herbert alcohol, the two containing In average 12 carbon atoms. Preferred polyols are α,β-diols and α,β-diols. Polyurethane-polyol compositions exhibit very low viscosity and are particularly suitable in coating compositions with very low content of volatile organics. Hardened coating obtained from claimed compositions ensure high resistance to cracking and can be applied on various substrates such as metal, plastic, wood, glass, ceramics.

EFFECT: increased strength of coatings on a variety of substrates.

5 cl, 3 tbl

FIELD: chemistry of polymers.

SUBSTANCE: invention relates to aromatic polyurethane polyols used as components of priming compositions. Invention describes the priming composition comprising aromatic polyurethane polyol including product of reaction: (a) at least one diol component among number of α,β-diols, α,γ-diols and their mixtures; (b) at least one triisocyanate; (c) at least one diisocyanate wherein at least one isocyanate is aromatic one, and molecular mass or aromatic polyurethane polyol is 3000 Da, not above, and a cross-linking agent also. Prepared aromatic polyurethane polyol shows viscosity value by Brookfield at the level 8260 centipoises, OH-number 192.6 KOH/g and the dispersity (Mn/Mw) at the level 3.0. Priming compositions prepared by using indicated aromatic polyurethane polyol are useful in finishing large means of transportation, for example, trains, trucks, buses and airplanes, in particular, in vehicle body works. Also, invention relates methods for applying priming compositions on support comprising applying indicated compositions, and to a method for finishing car in repairs comprising applying the indicated priming composition.

EFFECT: improved and valuable properties of composition.

11 cl, 5 tbl, 12 ex

FIELD: chemistry of polymers.

SUBSTANCE: invention relates to formulations of polyurethane elastoplastics designating for preparing soft polyurethane materials with Shore hardness value 45-55 conditional units. Invention describes the composition comprising 74.8-78.4 wt.-% of urethane pre-polymer based on 1.8 mole of 2,4-toluylene diisocyanate and 1.0 mole of polyethylenebutylene glycoladipinate of molecular mass 2000 Da and liquid hardening agent based on aromatic amine 3,3'-dichloro-4,4'-diaminodiphenylmethane and a mixture of oligoesters - polyethylene glycoladipinate of molecular mass 800 Da and polyethylenebutylene glycoladipinate of molecular mass 2000 Da taken in the mole ratio 0.34; 0.33; 0.33 (up to 100 wt.-%). Polyurethane materials prepared on the basis of such composition show Shore hardness value at the level 45 units, rupture strength limit (at 23°C) at the level 31.2 MPa, relative elongation at rupture 1100%, and they can be exploited at temperature -10°C.

EFFECT: improved and valuable properties of composition.

4 tbl, 5 ex

FIELD: polymer materials.

SUBSTANCE: invention relates to polyurethane elastomers suited to manufacture polyurethane articles. Composition according to invention contains (i) 70.6-74.8% polyfurite urethane prepolymer prepared by reaction between 2.1 mile 2,4-tolylenediisocyanate and 1.0 mole poly(oxytetramethylene glycol) with molecular weight 1500 and (ii) liquid curing agent (to 100%), which is a mixture of 3,3'-dichloro-4,4'-diaminodiphenylmethane and poly(oxytetramethylene glycol) with molecular weight 1000 at their molar ratio 1:1. Thus obtained polyurethane elastomers show Shore hardness al a level of 93 relative units, breaking point (23°C) at a level of 38 MPa, elongation on fracture 712%, and abrasion resistance 27 mcm (according to Russian standard GOST 11529-86). Articles manufactured from these elastomers may find use for in-tube flaw inspection of oil and gas mains as well as oil storage tanks.

EFFECT: enlarged assortment of industrially useful elastomers.

4 tbl, 6 ex

FIELD: polymer production.

SUBSTANCE: coating composition comprising at least one compound with at least two isocyanate functional groups; at least one compound reactive to isocyanate and having at least two groups reactive to isocyanate groups, which are selected from mercapto groups, hydroxyl groups and combinations thereof; and cocatalyst consisting of phosphine and Michael acceptor, amount of catalyst constituting from 0.05 to 20% of the weight of dry residue. Invention also describes a method for coating substance with indicated composition as well as coated substrate, and adhesive containing at least one compound with at least two isocyanate functional groups and at least one compound containing at least two above defined groups reactive to isocyanate groups. Moreover, invention discloses employment of composition for finishing of great vehicles and refinishing of motor cars. Composition is characterized by drying time at a level of 20 min, modulus of elasticity 1904, Persose hardness 303, and brightness (85°C) at a level of 100.

EFFECT: expanded coating assortment.

16 cl, 16 tbl, 48 ex

FIELD: new associative amphiphilic cationic polymers.

SUBSTANCE: polymers of formula I dissolvable or dispersible in water, as well as method for production and application thereof are disclosed. Claimed polymers are useful as thickening agents in cosmetic and therapeutic compositions. Composition containing polymers of present invention also are disclosed.

EFFECT: polymers of improved thickening ability and cosmetic quality.

13 cl, 4 ex

The invention relates to odnoupakovochnye polyurethane film-forming, curing air moisture, which can be used as a varnish or binder in the polymer compositions having anti-corrosion properties
The invention relates to a method for producing polyol as one compositions containing material in the form of particles in dispersed form, and the amount of material in the form of particles is 30-80 wt.% calculated on the whole composition

The invention relates to a new compound NlNlN2N2N3N3-hexa(2-oksipropil)-2,4,6-triaminotoluene formula I, which can be used as a crosslinking agent upon receipt rigid and flexible foams, and the method of its production Method is that 2,4,6-triaminotoluene subjected to interaction with propylene oxide in an autoclave at a temperature of 50-100Since, in the presence of a hydroxyl-containing solvent, preferably polyester or water

The invention relates to a method for glue-based diisocyanate and epoxy resin, which can be used for bonding wood, fabric, cardboard

FIELD: polymer materials.

SUBSTANCE: invention relates to polyurethane-polyol compositions comprising product of reaction of a polyol and Herbert alcohol, the two containing In average 12 carbon atoms. Preferred polyols are α,β-diols and α,β-diols. Polyurethane-polyol compositions exhibit very low viscosity and are particularly suitable in coating compositions with very low content of volatile organics. Hardened coating obtained from claimed compositions ensure high resistance to cracking and can be applied on various substrates such as metal, plastic, wood, glass, ceramics.

EFFECT: increased strength of coatings on a variety of substrates.

5 cl, 3 tbl

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