Method of producing nontoxic chipboards
FIELD: process engineering.
SUBSTANCE: invention relates to woodworking industry. Proposed method comprises preparing wood particles, drying and sorting them, making modifying carbamide-formaldehyde resin-based binder, mixing it with wood particles, producing carpet and moulding plates. Carbamide-formaldehyde resin modifier is made up of PVAC dispersion-based composition with ratio of components in wt % as follows: carbamide-formaldehyde resin - 67-92; PVAC dispersion - 5-20; carbamide - 1-5: plasticiser - 1-5, and curing agent - 1-3.
EFFECT: reduced toxicity of chipboards.
7 ex, 1 tbl
The invention relates to woodworking industry and can be used in the manufacture of non-toxic wood fibre boards.
A known method of manufacturing particle boards, namely, that in the mixture of wood particles and resin is injected under stirring leather particles (see RF patent №2032533, CL 27 No. 3/02, 1992).
A disadvantage of the known solutions is the high toxicity of the produced particle Board.
The closest known technical solution to the claimed is a method of manufacturing particle boards, consisting in adding a binder on the basis of urea-formaldehyde resin modifying agent, followed by mixing of the modified binder with wood particles, the formation of the Mat and press plates, at the same time as modifying additives in the resin using a silica Sol (see RF patent №2132272, CL 27 No. 3/00, 1997).
A disadvantage of the known solutions is the lack of decrease in toxicity of the plates.
The objective of the proposed solutions is to reduce the toxicity of chipboard.
The solution of this problem is that in the method of manufacturing a non-toxic particle boards, including manufacturing, drying, sorting of wood particles, the preparation of mo is aficionado binder based on urea-formaldehyde resin, mixing it with wood particles, the formation of the Mat and press plates, as a modifier of urea-formaldehyde resin use composition based on polyvinyl acetate dispersions in the following ratio of components of the modified binder, parts by weight:
|polyvinyl acetate dispersion||5-20|
The invention is illustrated by the following examples.
The finished chips from a mixture of coniferous and deciduous wood is dried to a moisture content of 1-3% and sorted. After that prepare a binder by mixing urea-formaldehyde oligomer and modifying additives in the following proportions, parts by weight:
|polyvinyl acetate dispersion||5|
Mixing the chips with a binder produced in the mixer at its normal dosing on absolutely dry residue 12% relative to the weight of absolutely dry wood shavings. Plate is pressed density of 700 kg/m3under the following operating parameters:
Temperature - 130°C; duration of 0.35 min/mm
Testing of physical and mechanical properties of the plates is carried out according to GOST 10632-2007. The content of free formaldehyde in the plates check method "Punch". Test data plates with a density of 700 kg/m3shown in table 1.
Example 2. Perform in example 1.
|polyvinyl acetate dispersion||12|
Example 3. Perform in example 1.
|polyvinyl acetate dispersion||20|
Example 4. Perform in example 1. The duration of pressing -0,45 min/mm
Example 5. Perform according to example 2. The duration of pressing -0,45 min/mm
Example 6. Perform in example 1. The temperature of the pressing - 160°C.
Example 7. Perform according to example 2. The temperature of the pressing - 160°C.
Thus, the invention allows the manufacture of particle Board with a low content of free formaldehyde.
|The test results of chipboard.|
|# example||The ultimate tensile stress perpendicular to the plate, MPa.||The content of free formaldehyde mg/100 g plate|
A method of manufacturing a non-toxic chipboard, including manufacturing, drying, sorting of wood particles, the preparation of the modified binder based on urea-formaldehyde resins, mixing it with wood particles, the formation of the Mat and press plates, characterized in that as a modifier of urea-formaldehyde resin use composition based on polyvinyl acetate dispersions in the following ratio of components of the modified binder, parts by weight:
|polyvinyl acetate dispersion||urea||1-5|
FIELD: process engineering.
SUBSTANCE: invention relates to using wax water dispersion as oil-wetting agent in producing wood-base materials. Wax dispersion contains soft wax with content of oil exceeding 20% by wt as solid phase or its component. Note here that soft wax is solid at, at least, 10°C and below, and features softening temperature below 65°C, and contains 0.5-10 % by wt of urea per wax dispersion weight. Soft wax-to-urea weight ratio varies from 100:0.3 to 100:6. Wax dispersion is brought in contact with wood chippings or fibers. Invention covers also wood-base material produced in using binders, soft wax and urea, and method of its production.
EFFECT: higher oil-wetting effect and better physical and chemical properties.
28 cl, 1 tbl, 2 dwg, 1 ex
SUBSTANCE: invention relates to wood material in which a nitrogen-containing compound is distributed, where the said compound forms a cellular structure and is a product of condensation of formaldehyde in form of a cellular structure formed in amount (N) of at least 1 wt % in terms of nitrogen, relative the total weight of the wood material. The coefficient (FA/N) which is expressed as the ratio of extraction of formaldehyde (FA), determined using a method in a closed volume in accordance with EN 717, part 3, to the quantitative content of nitrogen (N) has maximum value of 3.5×10-3, and the hold level of the nitrogen-containing compound is higher than 73%. The method of obtaining the wood material involves a) saturating wood material with an aqueous composition containing i) at east one nitrogen-containing compound which forms a cellular structure and ii) at least one substance which catalyses formation of the cellular structure, b) treating the saturated wood material at high temperature in order to remove water and to form a cellular structure from the nitrogen-containing compound which forms a cellular structure. Step b) of the process involves treatment of the saturated wood material at least once with superheated water vapour, followed by treatment at least once at temperature higher than 110°C and with relative humidity of the gaseous medium surrounding the wood material of not more than 20%. The nitrogen-containing compound which forms the cellular structure is selected from: 1,3-bis(hydroxymethyl)-4,5-dihydroxyimidazolidin-2-one, 1,3-bis(hydroxymethyl)-4,5- dihydroxyimidazolidin-2-one, which is modified by an alkanol with 1-6 carbon atoms, a polyol with 2-6 carbon atoms or oligoalkyleneglycol, 1,3-bis(hydroxymethyl)urea, 1,3-bis(methoxymethyl)urea, 1- hydroxymethyl -3-methylurea, 1- hydroxymethyl-3-methyl-4,5- dihydroxyimidazolidin-2-one, 1- hydroxymethyl -4,5- dihydroxyimidazolidin-2-one, 1,3-bis(hydroxymethyl) imidazolidin-2-one, 1,3-bis(hydroxymethyl)-1,3-hexahydropyrimidin-2-one, 1,3-bis(methoxymethyl)-4,5- dihydroxyimidazolidin-2-one, tetra(hydroxymethyl)acetylenediurea, low-molecular melamine-formaldehyde resins and low-molecular melamine-formaldehyde resins which are modified with alkanol with 1-6 carbon atoms, polyol with 2-6 carbon atoms or oligoalkyleneglycol, mixtures of said compounds with each other, mixtures of said compound with not less than one compound V', which contains at least one free NH- group, and mixtures of said compounds with at least one compound V" which contains at least one hydroxyl group which is not part of the CH2OH group.
EFFECT: wood material has low release of formaldehyde.
19 cl, 19 ex
SUBSTANCE: composition contains polyethylene production and/or household wastes, beet pulp and bentonite as a processing additive.
EFFECT: disclosed composition has rheological characteristics which meet requirements for polymeric materials for their possible processing on conventional equipment, as well as required operational characteristics, including biodegradability.
4 ex, 2 tbl
SUBSTANCE: invention describes a composition for a wood-polymer composite material containing the following, wt %: furfural-acetone resin 14-20, benzene sulphonic acid 3-5, andesite flour 47-57, technical soot 2.5-5.7, wood chips 16-20, broken glass or loose glass yarn 0.3-0.5, modified low molecular weight styrene-containing copolymer based on still bottoms from distillation of recycled solvent from production of polybutadiene 2.0-6.0 wt % maleic acid 1-5, and polyatomic alcohol 0.3-1.5.
EFFECT: composition enables to obtain wood-polymer composite material with high strength and frost resistance.
2 tbl, 6 ex
FIELD: process engineering.
SUBSTANCE: invention relates to treatment of vegetable lignocelluloses raw material to produce plate construction materials to be used in construction and furniture production. Vegetable lignocelluloses raw material with high content of lignin and hemicelluloses is treated for 15 s - 10 min by water steam at not over 1 MPa and 150-250°C. Treatment by water steam is instantly terminated. Said vegetable lignocelluloses raw material thus treated is mixed with untreated fibrous vegetable lignocelluloses raw material. Content of vegetable lignocelluloses raw material treated by water steam in produced mix makes 2-60 wt %. Produced mix is formed into mats. Water is extracted from said mats. Vegetable lignocelluloses raw material treated by water steam can be dried to moisture content of 5-10%. Resultant matter is mixed with untreated vegetable lignocelluloses raw material. Mats are produced from obtained mix and subjected to hot pressing. To produced solid plate material.
EFFECT: lower production costs.
5 cl, 3 ex
FIELD: process engineering.
SUBSTANCE: invention relates to production of plate materials based on cellulose-containing particles impregnated with glue base on carbamide-formaldehyde resin to be used woodworking industry. Cellulose-containing particles are mixed with glue based on carbamide-formaldehyde resin and acid solidifier. Said cellulose-containing particles represent flax boon. Note here that said glue comprises additionally modifier butanol-1 in amount of 1.4…1.6% of carbamide-formaldehyde resin weight.
EFFECT: production of new structural material with increased physical and mechanical properties.
1 cl, 2 tbl, 2 dwg
SUBSTANCE: aqueous solution of the product of reacting a composition used for products made from recycled wood material, essentially consisting of an acid source with pKa in water ranging from 2 to 8, a base source with pKb in water ranging from 2 to 6 and urea, in which the composition contains from 0.1 to 70 wt % acid, from 0.1 to 50 wt % base and from 1 to 55 wt % urea, where the rest is water, is effective for enhancing polymerisation of urea-formaldehyde resin. The composition which is capable of hardening urea-formaldehyde resin can contain urea-formaldehyde resin which is capable of hardening and the above described composition and can be obtained by mixing the resin with the said composition. A panel made from recycled wood material can be made by mixing crushed lignocellulosic material and the said urea-formaldehyde resin which is capable of hardening and hardening the resin. The concentrate for preparing the polymerisation enhancing composition used for products made from recycled wood material contains an acid source with pKa in water ranging from 2 to 8, a base source with pKb in water ranging from 2 to 6 and urea.
EFFECT: increased resistance to breaking up of the plates during hot piling and further hot pressing.
19 cl, 6 ex, 9 tbl
FIELD: mechanical engineering.
SUBSTANCE: invention can be used in mechanical engineering for fabrication of big size bearing and sliding elements of light and medium loaded friction units operating with organic lubricant. Here is disclosed antifriction wood-polymer material made out of composition containing crumbled wood, polymer binding - mixture of polyethylene and polypropylene, modifier of polymer binding - maleic anhydride, lubricant - mixture of mineral oil and polyethylene wax and additionally - fly ash.
EFFECT: raised impact strength and tribo-resistance at wear, reduced water absorption of antifriction material.
2 cl, 2 tbl, 5 ex
FIELD: construction industry.
SUBSTANCE: invention refers to wood-working, furniture and construction industry. In order to develop non-toxic plate material, it is proposed to use moulding material from plant raw material without using synthetic binders. Moulding material in the form of plant raw material particles containing cellulose, lignine, easy- and difficult-to-hydrolyse polysaccharides and carboxyl groups is obtained by means of cavitation treatment of plant raw material; at that, it contains easy- and difficult-to-hydrolyse polysaccharides 13-18% and 28-37%, correspondingly, cellulose with copper index of 1.7-2.9 g/100 g - 53-58 %, lignine (Komarov) 31-37% and carboxyl groups 0.6-4.9 %.
EFFECT: cheap plate materials having high ecological and physic and mechanical properties are obtained from moulding material.
6 cl, 1 ex, 5 tbl
SUBSTANCE: invention is related to the field of composite materials on the basis of lignocellulose materials, in particular to press-compositions, and may be used in wood processing and construction. Composite material is produced from binder - acetylated wood of aspen with additional introduction of additive - powdery inorganic substance from the following group: Al, AlCl3*6H2O, Al(OH)3, at the following weight ratio of components, wt %: Lignocellulose binder - from 30 to 70, additive - the rest.
EFFECT: invention assists in increase of composite materials compositions, increase of strength, heat resistance and water resistance of composites.
4 ex, 2 tbl, 3 dwg
FIELD: process engineering.
SUBSTANCE: proposed method comprises crushing chipwood into shavings. The latter is dried, glue is applied thereon and shavings is filled thereon to produce shavings carpet to be compressed thereafter at certain temperature. Prior to cutting, water steam is fed onto wood chipwood. Wood chipwood, at least, frozen partially through is used. Prior to cutting, it is thawed and dried. Proposed device comprises machine tool to produce chipwood, chipwood drier, appliance for glue application and press. Proposed device differs from known designs in that in incorporates hopper intended for feeding steam onto chipwood contained therein, steam temperature and amount regulator, and chipwood drier. Note here that steam temperature and chipwood amount are controlled to implement above described method.
EFFECT: high process rate using perfected device for production of particle boards.
16 cl, 2 dwg
FIELD: wood working industry.
SUBSTANCE: invention relates to the field of production of wood-particle composite materials and relates to wood-particle composite material and method of its manufacturing. Material contains pressed wood-particle filler and binder, material has monolithic low-porosity structure characterized by achieved density of up to 2 g/cm3, thickness of chips makes from 0.1 to 1.0 mm, pores of wood-particle filler are fully filled with binder, such as wood resinous substances that are released from chip filler in process of its hot pressing as composite material is made. Method of manufacturing consists in the fact that filler is pressed as wood chips in presence of binder, at the same time binder is used, which is released from chips as it is pressed with pressure of 2-5 MPa, besides puncheon and die of press are pre-heated to temperature of 220-300°C, and process of hot pressing is carried out in cyclic loading mode.
EFFECT: invention makes it possible to increase efficiency of wood-particle composite material manufacturing method and to improve quality, due to increased strength, water resistance and fire resistance of manufactured wood-particle composite materials.
FIELD: technological processes.
SUBSTANCE: method for manufacturing of boards from chip or fibre material, in particular chip boards, LDF, MDF, HDF and OSB boards, includes the following stages: (S2) - production of dried chip or fibre material, (S3a, S3b) - plasma treatment of dried chip or fibre material, (S4a, S4b) - application of glue onto plasma-processed chip or fibre material and (S5) - pressing chip or fibre material, on which glue is applied into boards. Technological gas used at stage (S3a, S3b) of plasma treatment contains fluorine as additional component. Board contains not more than 50 kg of hard glue per cubic metre.
EFFECT: invention improves quality of boards.
13 cl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to production of construction and heat insulation materials. Proposed complex comprises crusher, hopper, mixer, reed powder hopper, reed powder feed conveyor for production sandwich panels with vacuum-powder insulation or materials made from cheff or reed powder heated to 190-200°C to separate resin-based adhesive, rolls, molds and acclimatizator heated to over 200°C and oscillating at preset rate, and arranged under said conveyor. Note here that hopper is furnished with mixer and hot water circulation jacket and jacket with branch pipe to feed heat carrier and to dry cheff to 90-95°C. Mixer is communicated with vertical heated mill furnished with hot water circulation jacket.
EFFECT: production of new heat insulation material.
2 cl, 6 dwg
SUBSTANCE: invention is related to epoxide-wood composition for production of pressed boards used to cover foam polystyrene plates from external and internal sides on glue in order to protect them against external impact and to increase their service life. Composition includes the following components, with their following ratio, wt %: 37.2-43.5 of epoxide-diane resin ED-20, 3.7-4.3 of amine hardener of polyethylene polyamine, 43-52.1 of pine woodchip filler, 6.3-11.9 of polymer filler. Polymer filler used in composition is foam polystyrene chips - wastes of heat insulation production.
EFFECT: invention makes it possible to increase physical and mechanical characteristics of composition, to recycle wastes of wood processing and heat insulation materials.
2 tbl, 3 dwg
FIELD: technological processes.
SUBSTANCE: invention is intended for woodworking and construction industry, and also environmental protection, and may be used in production of different construction materials, furniture panels, etc. Particles of organic filler, in particular wastes of woodworking industry, are ground to size of 1-0.25 mm, fractioned and dried to moisture extent of 3% and below. Then particles of this component and thermoplastic binder are charged with opposite electric charges by means of their supply to surface of rotor that rotates with circumferential speed of 80-120 m/s. As thermoplastic binder you can use domestic waste, such as polyethylene bags, containers. Charged particles of filler and binder are mixed. Mass prepared in mixer is sent through overbridge equipped with bipolar ioniser. Length and diametre of overbridge are such that they provide time of 10-12 sec for mass staying, which is sufficient to achieve residual charge of static electricity by voltage value of 20-500 V/cm. Invention makes it possible to produce cheap items by simple method with density of 0.99-1.00 g/cm3 and flexural length of at least 42 MPa, to recycle wastes, improve ecology and reduce toxicity of items.
EFFECT: production of cheap items by simple method with density of 0,99-1,00 g/cm3 and flexural strength of at least 42 MPa, recycling of wastes, improved ecology and reduced toxicity of products.
1 dwg, 1 tbl
FIELD: wood industry.
SUBSTANCE: invention pertains to production of chipboards. The board includes bottom and top surface layers with fine particles, and an intermediate layer with more coarse particles is placed between these surface layers. The intermediate layer has various density in the areas, where the board is supposed to be attached to an other object. The chipboard production method includes even distribution of fines followed by generation of the first particle matrix to form a bottom surface layer, distribution of more coarse particles followed by generation of the second particle matrix above the fine particle matrix using a distribution device so that at least in one zone the coarse particles are applied in a more thick layer than at least in one surrounding area, even distribution of the fine particles followed by generation of the third coarse particle matrix to form a top surface layer and compression of the first, second and third matrices, whereby the intermediate layer thickness remains virtually unchanged, so the intermediate layer has various density.
EFFECT: produced chipboards feature increased soundproof and heat-insulating properties, and light weight, that facilitates efficient shipment of the processed boards.
9 cl, 13 dwg
SUBSTANCE: method of construction beam production out of modified wood involves wood modification by squeezing fine metal powder into lumber cavity, with further formation of lumber face by rolling even surface before feeding it into reverse mold, where lumber is put by metal faces together. Then ultra high frequency (UHF) current is applied to beam ends to mollify metal powder, and modified materials are connected in reverse mold by pressing, at the moment of which UHF current is switched off, and obtained seam is cooled, finished beam is extracted from reverse mold freeing it for next beam pressing.
EFFECT: obtainment of construction beams of specified shape and strength properties.
1 dwg, 1 tbl
SUBSTANCE: converted timber or chip plate is made of eucalyptus breeds and connected by means of binding substance containing isocyanatic or phenol polymeric compound. Eucalypti of the following species were selected: Bluegum (E. Globulus), Karri (E. Diversicolor), Sydney Bluegum (E. Saligna), Marri (E. Calophylla) or Jarrah (E. Marginata).
EFFECT: high surface strength, wet resistance and low swelling ratios.
10 cl, 1 dwg
FIELD: technological processes.
SUBSTANCE: method includes grinding of woodworking wastes or plant materials, mixing with binder and subsequent pressing. Binder is liquid sodium glass that contains dry substance of glass 30-70; water 70-130 wt parts; at that cold pressing is executed, and binder is taken in amount of 20-50 wt parts per 100 wt parts of wastes. Binder may additionally contain hardener - salts of mineral acids in amount of 3-5 wt parts, in this case liquid sodium glass is preliminarily homogenised with hardener.
EFFECT: invention makes it possible to prepare ecologically clean, thermally resistant and moisture resistant items.
8 cl, 3 tbl
FIELD: wood-working industry; production of pressed building items.
SUBSTANCE: the group of inventions is pertinent to the field of production of pressed building items made out of plant roughage and may be used in wood-working construction industries and other branches of economy. The panel made by pressing out of a carpet without synthetic binding materials consists of a mixture of a birchen bark ground up to a faction of 40-5000 microns and a filler predominantly out of cellulose filaments at the following ratios in respect to the total dry solid matter (in mass %): a birchen bark - 60-95, cellulose filaments - 5-40. In an alternative version of the panel, which is made the same way as the above, the outer surfaces of the carpet are strengthened with lingo-cellulose-polymeric compound including an excelsior and the KF-EC resin with a hardener or an excelsior and triturated secondary polymer taken in amount of 10-12 mass % to the weight of the excelsior. At that the share of the lingo-cellulose-polymeric compound makes 20-40 % to the total dry weight of the carpet. The method allows to use a ground birchen bark without synthetic binding agents for shaping a carpet and its consequent pressing. At that for a carpet formation they use the birchen bark ground up to a faction of 40-5000 microns, and a filler mainly made out of cellulose filaments taken in the following ratio in respect to the total dry weight(in mass %): a birchen bark-60-95, cellulose filaments - 5-40. Before formation of the carpet the filler is moistened up to 18-20 % of absolute humidity and is mixed with ground birchen bark. The carpet is formed with a thickness equal to 200-300 % of the thickness of a finished panel. The group of the inventions ensures simplification of the production process, reduction of its cost, expansion of the range of the List of items.
EFFECT: group of the inventions ensures simplification of the production process, reduction of its cost, expansion of the range of the List of items.
8 cl, 1 tbl