- Description and chemical composition
- Polymer to wood ratio
- Material advantages
In construction and in the manufacture of furniture, new high-tech materials are used with improved properties compared to conventional materials of the same class, and their price is lower. One of these materials is wood-polymer composite (WPC). Now it is widespread due to its availability and low price. It is cheaper than regular wood, but has the same durability.
In the manufacture of the composite, natural wood and polymer are used, which does not harm human health. Typically, WPC is produced by casting, which significantly increases its strength.
The composite can be used when laying flooring. It is used when installing railings on open terraces, in gazebos, on balconies, since it is resistant to temperature extremes, any precipitation, and mechanical stress. This makes the WPC versatile. The material has a beautiful structure.
WPC is common in the USA, where it is actively used in the construction of cottages.... Production technology, characteristics are important to know if you have chosen this material. If you know the features of the process of making liquid wood, then you can make a composite with your own hands.
Description and chemical composition
Wood-polymer composite, called liquid wood, is a man-made material made by mixing wood and monomer. During the manufacturing process, extrusion takes place to form a polymer. In a similar way, a polymer board is made, which is superior in strength to ordinary wood, but slightly inferior ceramic tiles... The boards themselves take shape during the casting process.
"Liquid wood" is produced by adding binder polymers to the shavings: polystyrene, polyethylene, polypropylene and polyvinyl chloride. WPC got the name "liquid tree" because of its flexibility and ductility.
"Liquid wood" is used in the production of floorboards, siding, pipes (for water supply, sewerage), furniture.
The chemical composition of WPC includes only 3 components:
- Small particles of wood (shavings, sawdust, shredded wood, abroform, cheap models come across sunflower cake, shredded plywood). The amount of the additive can vary in composition from 1/3 to 4/5 of the total mass.
- Polymer additive - polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP).
- Special chemical additives that significantly improve technical properties, appearance(dyes, varnishes). The volume of these additives is 0.1–4.5% of the total mass.
Polymer to wood ratio
The proportions of the ratio of polymer and wood can be different. The selection is carried out taking into account what technical indicators of the WPC are required.
Wood (abroform) to polymer has a ratio of 2: 1. This ratio gives the WPC the properties of wood - the mass will contain more wood fibers. Boards made of such material will swell from moisture, which significantly reduces the service life in a humid climate. For middle lane and southern Russia it will be 5-10 years. WPC turns out to be relatively fragile, which limits its use, however, the building material has a beautiful wood texture and "corrugated" surface.
The ratio of wood to polymer, like 2: 3, significantly degrades the appearance of WPC boards, which limits the use of boards for decorative purposes. The board feels like ordinary plastic to the touch, and the surface becomes smoother (sometimes slippery).
If the wood-polymer composite has a ratio of wood fibers (abroform) to polymer 1: 1, the board acquires optimal performance... The texture is beautiful, with a rough surface, non-slip. The casting process is simplified: there is no need to heat the components to the required temperature. The preparation of WPC in this way does not transfer the properties of wood to the material: it does not absorb moisture, does not swell, and is relatively durable in use.
Liquid wood is poured into special forms, which provide for the presence of thorns and grooves for fixing the boards.
Material advantages
WPC is resistant to ultraviolet radiation: it does not crack, does not deform. It does not change its structure when low temperatures air, exposure to moisture, acids and other negative environments.
The material is resistant to mold, insects do not start in the WPC, it is not a bait for mice, rats and other rodents. For greater stability, it can be covered with a special polymer film.
Another plus is a higher strength (it allows you to withstand more than 5 centners per 1 m 2). This makes it possible to place any heavy furniture on the boards.
Liquid wood is a flexible material that can be easily processed... It can be sawn, planed. This is taken into account in the production of polymers or in the casting process.
Liquid wood - ecologically clean material, since the abroform and polymer used do not emit toxic substances and do not pose a danger to humans. WPC is non-flammable and does not support combustion.
Is it possible to make it yourself?
It is possible to make a "liquid tree" (abroform) at home, while a hand-made WPC will have the necessary characteristics. Blanks are suitable for restoration work (furniture), rough flooring for auxiliary rooms, gazebos, terraces.
To make liquid wood, you need to take sawdust and grind it using home mills or coffee grinders. PVA glue is added to the mixture (sawdust to glue ratio 70:30). The resulting mixture should be thick. In order for the material to have the desired color, it is recommended to add paint (enamel) of a suitable color.
The resulting mass is an analogue of the WPC. The material can be applied to damaged areas of parquet, laminate, furniture.
If you fill the floor with such material, then formwork must be made under it, and the mixture itself must be prepared in the required volume. Then you can start pouring. The recommended thickness of the future board is 50 mm.
The production of ligno-carbohydrate wood plastics is a new industry. The problem of obtaining plastic materials from crushed wood particles without the addition of binders due to decomposition products of wood components has long occupied researchers. Many options for piezothermal treatment of wood particles were proposed, which differed in modes, but essentially all these methods involved the treatment of wood particles with high pressures and press temperatures, in hermetically sealed molds. Subsequently, the plastics obtained in this way were called piezothermoplastics.
Currently, in our country, two methods have been proposed for obtaining piezothermoplastics:
1. The one-stage method, developed at the Belarusian Technological Institute, provides for grinding wood to a state close in particle size to wood flour, and pressing it in sealed molds at a pressure of 250-300 kg / cm 2 and a temperature of 190-200 ° C. subsequent cooling to 20 ° C without relieving pressure.
2. The two-stage method, developed at the Leningrad Forestry Academy, involves preliminary partial aqueous hydrolysis of wood particles in an autoclave followed by pressing the dried, partially hydrolyzed material in a mold in a hot press. Preliminary hydrolysis will reduce the pressing pressure for pressing materials made from wood of some hardwoods to 150 kg / cm 2 and the temperature of hot pressing to 160 ° C.
At the department of wood science and construction business and in the problem laboratory of wood plastics of the Ural Forestry Institute under the guidance of prof. From 1962 to the present, V.N.Petri has been conducting versatile studies of new materials - ligno-carbohydrate wood plastics, obtained by using the reactivity of wood components (natural lignins and polysaccharides), without adding thermosetting resins or other binders to wood particles.
The authors of the new method, in contrast to the proponents of piezothermoplastics, believe that when obtaining plastics, wood should not be subjected to deep destruction, but only by mild effects during piezothermal treatment, in which at the first stage of processing there is a partial hydrolysis of polysaccharides (primarily water-soluble and easily hydrolyzed) with the formation of some quantities of organic acids, which carry out the hydrolytic cleavage of the natural ligno-carbohydrate complex, since it is known that at least small amounts of an acid catalyst are required to destroy the chemical bond between lignin and carbohydrates.
As a result of these processes, not monomers appear, but larger molecules that retain the natural reactivity of the main components of wood - carbohydrates and lignin. In the manufacture of plastics, wood should not be subjected to deep destruction, since this destroys the reactive components of natural wood.
In the process of piezothermal treatment, it is also necessary to provide opportunities for subsequent interaction between the reactive components of individual wood particles in order to synthesize new ligno-carbohydrate complexes. Thanks to this, the formation of durable and water-resistant plastic from wood particles occurs. New materials named ligno-carbohydrate wood plastics(LUDP). Ligno-carbohydrate wood plastic (LUDP) is a new board material obtained by hot pressing wood particles without the addition of binders. Ligno-carbohydrate wood plastics have a number of features that make their production economically viable:
1. The main advantage of LUDP, from this point of view, is that there is an unlimited amount of raw materials for their manufacture. These are wood particles of any of the most common conifers (pine, larch, spruce, cedar, fir) and deciduous species (birch, aspen, etc.), as well as their mixtures.
The production of LUDP can be established in any region of our country where logging and woodworking enterprises operate, since plastics can be made from any waste from logging and wood processing, as well as from firewood (without limiting the content of rot and bark).
On the basis of technical and economic calculations, it has been established that the minimum capacity of the workshop for the production of LUDP is 3.5-4 thousand m 3 of plates per year; the demand for raw materials for such a shop is 10-12 thousand m 3. Consequently, the production of LUDP, in contrast to the production of particle boards, can be organized in small enterprises.
2. Ligno-carbohydrate wood plastics are obtained by using the reactivity of the components of the wood itself, ie, without adding thermosetting resins or other binders to wood particles.
3. The technological process of LUDP production in comparison with the production of particle boards is simpler, since there are no technological operations for the preparation of binders and mixing them with wood particles.
4. For the manufacture of LUDP use standard pressing and other equipment used for the production of particle boards and serially produced by the domestic industry.
Basic technical properties of flat single-layer LUDP the following:
1. Appearance and color... After pressing, LUDP boards have a middle, darker (conditioned) part and a light edge along the periphery, or substandard part of the board. The substandard part of the slab under optimal pressing conditions does not exceed 10 cm. When using large slabs, the 10 cm wide edge makes up only 2-5% of the area of the pressed slab. For example, with the size of the pressed plates 3100X1100 mm, the edge with a width of 10 cm is 2.5% in area. The width of the substandard part of the slabs can be reduced.
The color of the conditioned part of the board, pressed under optimal conditions, depends on the tree species from which the plastics are made, but is always much darker than that of the original wood and ranges from light to dark brown. The bark disturbs the uniformity of color. By coloring the wood particles of the outer layers of the formed carpet and making slabs faced with various decorative materials, the color and appearance of the slabs can be changed.
2. Surface quality... Boards made of fine and flat wood particles have a smoother and flat surface than boards compressed from thick and coarse wood particles. When pressing plastics from small wood particles on well-finished (better polished) pallets, the boards have a smooth, shiny surface.
3. Warping... The warpage of the LUDP depends on the thickness and design of the slabs. Thin slabs tend to warp more than thick slabs. Three-layer slabs warp less than single-layer slabs, and slabs lined with veneer are slightly more warped than non-lined ones. In order to avoid warping of the LUDP boards during conditioning, the rules for laying the boards must be strictly followed and the modes of their conditioning - drying must be observed.
4. Density... The density of ligno-carbohydrate wood plastics cannot be less than 1 g / cm 3. Only at this density is the minimum degree of compaction of the pressed mass ensured, at which the necessary contact and the possibility of chemical interaction between individual wood particles are achieved.
5. Moisture absorption... LUDP to a certain extent retains one of the main features of wood - to absorb moisture from moist air. With an increase in the content of hygroscopic moisture in plastics, their mechanical properties decrease:
a) LUPD with a density of not less than 1.2 g / cm 3 have a swelling of 7-10%, water absorption of 5-12%, a total moisture content of 20-22%;
b) LUDP with a density of 1.20-1.15 g / cm 3; swelling 10-12%, water absorption 12-15%;
c) LUDP with a density of 1.15-1 g / cm 3; swelling 18-25%, water absorption 20-26%.
6. Thermal properties... The material used for floors in residential and industrial buildings is characterized by a coefficient of heat absorption, which should not exceed 10 kcal / m 2.
Lignocarbon wood plastics with a thickness of 10-11 mm allow you to arrange floors by directly laying them on a concrete base.
7. Biostability... LUDP have a high anti-rotting resistance, which is 4-5 times higher than that of pine wood.
Mechanical properties of LUDP... Flat single layer uncoated LUDP slabs can be divided into three groups.
Group A - ultimate strength in static bending not less than 270 kg / cm 2 (density more than 1.2 g / cm 3), group B - ultimate strength in static bending not less than 220 kg / cm 2 (density 1.2-1, 18 g / cm 3); group B - ultimate strength in static bending not less than 120 kg / cm 2 (density 1.15-1 g / cm 3).
The physical and mechanical properties of ligno-carbohydrate wood plastics obtained from spruce logging residues are as follows: the ultimate strength in static bending is 170-190 kgf / cm 2, the swelling in 24 hours is 8-11%, and the density is 1.2 g / cm 3. Plastics made from crushed (1: 1 mixture) birch and aspen have a static bending strength of 176 kgf / cm 2, swelling in 24 hours - 16% and a density of 1.18 g / cm 3.
Manufacturing process is generally the same for all types of single layer, unfaced lignocarbohydrate plastics. The only difference is that for each specific type of raw material used for the manufacture of LUDP, different preparation of raw materials and different modes of pressing and conditioning of plastics are required. Therefore, the organization of industrial production of plastics at a particular enterprise should be preceded by research, aimed at clarifying the technology of their manufacture from available raw materials. These studies can be carried out in parallel with the design and construction of the plastics manufacturing plant.
V general view The technological process of LUDP production consists of the following main operations: preparation of raw materials, drying of raw materials, dosage of wood particles, formation of a carpet (package), cold pre-pressing of a carpet (package), hot pressing and cooling, hot pressing mode, trimming boards, conditioning - drying boards - plastics.
Scheme of the technological process for the production of LUDP by hot pressing from sawmilling and woodworking waste using one hydraulic press.
Branches, small-sized trunks, rotten spitting out of firewood, etc. are crushed on a chipper or crusher and fed by a conveyor or pneumatic conveyor into a hopper for a stock of chopped wood pulp, which can also receive sawdust, shavings or screenings from technological chips, chip production, etc. To obtain conditioned wood particles, wood pulp, previously cleaned of metal inclusions using a metal detector, is passed through a DO-5.7 flaking machine, and then through cross-shaped mills of the DM-3 brand. The openings of the sieve drum of mills for some rocks are reduced to 3 mm. After crushing, wood particles are sucked in by a fan and transported to a cyclone installed under the metering hopper.
The dosing device of this hopper allows you to change the amount of dispensed chips per unit of time, which is necessary to maintain the required temperature regime in the chamber of the drying plant.
The shavings are loaded into the installation chamber by a screw conveyor.
The fluidized bed dryer consists of two parallel sections. The drying agent is heated air. Air is blown in by fans. Crushed crushed to the required moisture content through the drain thresholds of the drying chambers enters the sluice feeders, and then into the suction pneumatic conveying pipeline. The air, passing through the layer of shavings in the drying chambers, carries away dust, which settles in the cyclone with an increased cleaning coefficient. Air cleaned of dust, but with high humidity is emitted into the atmosphere, and dust is sent together with the bulk of the material to the dry chip bin.
From this hopper, the shavings are uniformly fed by the dispensing device onto the belt conveyor 2 to the feeders and are distributed over the forming machines with fractionating rollers. The machines are laying the carpet on pallets. The formation of the sides of the carpet is carried out by two, vertical belt conveyors. Then the pallet with the loose carpet laid on it is moved by another section of the chain conveyor to press the carpet into a cold pressing press. The carpet is pressed under a pressure of 25 kg / cm 2 for 1 minute.
Before loading the package into a cold press, a duralumin gasket is placed on top using a rebar with suction cups. This contributes to uniform heating of the package and allows you to get a board with a high-quality surface on both sides.
Packages are collected in the press loading rack. After the stack is completely filled, all press spans are loaded simultaneously.
After the end of pressing, all plastic plates are simultaneously unloaded into an unloading stacker, from which they successively, starting from the bottom, are fed to the longitudinal and transverse conveyors.
Plates of plastic are transferred from the lower pallet to the three-sawing machine by the removal mechanism. The pallets, after cleaning and applying talcum powder, are directed under the forming machines.
Plates of plastic, after trimming the light edges, are sorted. Rejected slabs are cut into smaller ones with cutting out defective places. After sorting, high-quality slabs are stacked on pads and loaded into the conditioning and drying chambers using a traverse trolley. After unloading from the chambers, the slabs are placed in dense stacks in a heated room. Then they are packed and sent to the finished product warehouse for shipment to the consumer. (Technological operations following the cutting of plastic slabs are not shown in the diagram.) It is possible to increase the productivity of the LUDP workshop by increasing the size of the slabs, the number of stories of presses or their number.
High physical and mechanical properties of LUDP, beautiful appearance and the ability to manufacture large slabs allow them to be used in construction as a structural and finishing material for flooring, filing ceilings, manufacturing of built-in furniture, installation of partitions, door leaves, window sill boards, for wall cladding and panels in public buildings, in kitchens and corridors of residential buildings, etc., in furniture and other industries, as well as as a substitute for solid wood, chipboard and fiberboard and other sheet materials. Plates have a smooth surface and are well finished with transparent and opaque varnishes and paints using conventional technology. Finishing with transparent furniture varnishes can be done with preliminary surface tinting with water-soluble and other dyes in any color while preserving the texture of the boards.
Thus, when crushing branches and small size, the yield of conditioned chips is on average 50% of the total crushed mass. These conditioned chips can be used to make semi-cellulose, make particle boards and fibreboards, and 50% substandard chips can be used to make ligno-carbohydrate wood plastics or fertilizers.
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Purpose: the invention relates to the production of wood plastic products. The essence of the invention: a gap is preliminarily formed along the entire perimeter of the inner working part of the mold, into which a layer of wood-polymer material containing 10 - 30% of a thermoplastic binder is placed, after which the remaining volume of the mold is covered with wood particles with a moisture content of 6 - 25% ... Hot pressing is carried out at a pressure of 70 - 120 kg / cm 2 and at a temperature of 170 - 200 o C, and the ratio of the thickness of the layer of wood-polymer material and the thickness of the product is (1-2): (5-50). Wood particles are poured into a mold with a size of not more than 0.5 mm, and a layer of wood-plastic material can be formed by stacking pre-made plates of wood-plastic material. 7 p.p. f-crystals, 5 dwg., 1 tab.
The invention relates to the field of production of wood plastics from waste wood processing industrial production and can be used as building materials / facing boards, flooring, tiles, in furniture production /. There is a known method of manufacturing from woody and other plant substances, in which wood particles are placed in a sealed mold, heated without air access and the release of vapors and gases under a pressure of 1-50 MPa and kept at a maximum pressure of 3 to 70 minutes (SU, ed. St. N 38290, class E 04 C 2/10, 1934). The disadvantage of this method is the low value of the physical, mechanical and operational characteristics of the resulting products. The closest in technical essence and the achieved result is a method of manufacturing building products from wood plastics, including shredding wood, heating it to 170 - 270 o C and pressing in a sealed mold without air access and the release of vapors and gases at a pressure of 5 - 50 MPa within 3 - 70 min / SU, ed. St. N 38070, cl. E 04 C 2/10, 1934 /. These methods have the following disadvantages: the complexity of solving the issue of sealing the mold during hot pressing under pressure, the instability of the properties of products in violation, at least partially, of sealing, the appearance of open porosity when using reduced pressing, in which it is easier to ensure sealing. The presence of open pores impairs the physical, mechanical and operational characteristics of the wood plastic product, in particular, water absorption. The objective of the invention is to simplify the sealing of the mold while increasing its reliability and improving the physical, mechanical and other operational properties of products made of wood plastics. The task of creating reliable tightness of the mold is carried out by placing a layer of wood-polymer mass in the gap between the dies and punches. When the mold is heated to the pressing temperature, the wood-polymer mass acquires plasticity, flows under the pressing pressure into the gap between the die and the punches, which ensures reliable tightness of the mold. The required viscosity of the mass, ensuring reliable tightness, depends on the amount of thermoplastic binder and is determined by the pressing pressure, as well as the pressure of vapor and gases arising from the hydrolysis of wood particles. An increase in performance, in particular a decrease in porosity, is achieved by creating a layer of wood-polymer waterproof material on the surface of the wood plastic. This layer during the manufacture of the product ensures the sealing of the mold during pressing. The surface waterproof layer is formed during the pressing process by layer-by-layer loading of the mold: first, the lower horizontal layer containing wood particles and 5 - 30 wt.% Of thermoplastic binder, then a layer of wood particles and an upper horizontal layer similar to the lower one. The surface horizontal waterproof layer can be formed from thin sheets of wood-polymer material pre-made by pressing, containing 5 - 30% of a thermoplastic binder, and their subsequent laying in layers in a mold: the bottom and top layer - wood-polymer material, between them - wood particles. A sheet of wood-plastic material is placed between the walls of the mold and the layer of wood particles. The filling of the mold according to the prototype and according to the invention is carried out according to the schemes shown in FIG. 1-5. FIG. 1 shows a diagram of the charge backfilling according to the prototype, in which the entire mold 2 is filled with the pressed mixture 1, and the compaction is carried out by installing rubber seals 3 placed in the gap between the matrix and the punch around the entire perimeter of the inner working part of the mold. FIG. 2 shows a diagram of filling a mold, according to which, first, a layer 1 of wood-polymer material containing 10 - 30% of a binder is poured around the entire perimeter of the inner working part of the mold, and the remaining volume is filled with wood particles 2 with a moisture content of 6 - 25%. FIG. 3 shows a diagram of the filling of the mold, according to which, first, pre-made plates 1 of wood-polymer material containing 10 - 30% of a binder are laid around the entire perimeter of the inner working part of the mold, and the remaining volume is filled with wood particles 2 with a moisture content of 6 - 25 %. FIG. 4 shows a diagram of filling a mold, according to which, in addition to laying layer 1 of wood-polymer material containing 10 - 30% of a binder, a lower horizontal layer 2 of wood-polymer material containing 5 - 30% of a binder is poured onto the bottom of the mold, then wood particles 3 with a moisture content of 6 - 25%, on top of which a horizontal layer 4 is also poured, the composition of which is similar to the lower horizontal layer. FIG. 5 shows a diagram of filling a mold, which is similar to that of FIG. 4 with the difference that the horizontal layers 1 are not formed by filling a mixture of binder and wood particles, but by laying plates previously made of wood-polymer material. These horizontal layers, after pressing and cooling the products, form surface watertight layers. In this case, when preparing a wood-polymer mixture from a thermoplastic polymer binder, for example, polyethylene and wood particles, formic or acetic acid is introduced into the particles before mixing with the binder, and the moisture content of the particles is increased to 5-25%, and vegetable fibers can be used instead of wood particles. Samples of wood plastics were made according to the prototype method by hot pressing in a sealed mold. The gap between the die and the punches was sealed using a water-cooled gasket made of temperature-resistant rubber. Wood plastics according to the proposed method were made in a conventional mold with a gap between the punch and the matrix up to 1 - 1.5 mm. In both cases, to obtain wood plastics, coniferous wood particles with a size of -0.5 mm and a moisture content of 15% were used. To seal the matrix and create a protective water-repellent layer according to the proposed method, a press compound of the following composition was used: wood particles with a moisture content of 15% / conifers with a size of 0.5 mm / -85%, secondary polyethylene - 15% by weight. The hot pressing mode was the same for all samples of wood plastics: pressing temperature - 170 o C, pressure - 70 kg / cm 2, holding time under pressure - 30 min. The table shows the properties of wood plastics obtained by the prototype method and the proposed method. Analysis of the properties listed in the table of products made of wood plastics manufactured according to the prototype method and according to the invention in accordance with the mold filling schemes / cm. fig. 2 - 5 /, showed the following: the sealing of the mold placed in the gap between the die and the punch of the press mass is simpler and more reliable and provides higher physical and mechanical characteristics products than when using rubber seals; obtaining products with horizontal surface layers from a wood-polymer mixture ensures the waterproofing of products and an increase in their physical and mechanical characteristics.
Claim
1. A method of manufacturing products by pressing from wood plastic, including shredding wood, filling a mold, hot pressing under pressure without air access and release of vapors and gases, followed by cooling, characterized in that preliminarily, along the entire perimeter of the inner working part of the mold, a gap in which a layer of wood-polymer material containing 10 - 30% of a thermoplastic binder is laid, after which the remaining volume of the mold is covered with wood particles with a moisture content of 6 - 25%, and hot pressing is carried out at a pressure of 70 - 120 kg / cm 2 and at a temperature of 170 - 200 o C, and the ratio of the thickness of the layer of wood-polymer material and the thickness of the product is (1 - 2): (5 - 50). 2. The method according to claim 1, characterized in that wood particles, the size of which is not more than 0.5 mm, are poured into the mold. 3. A method according to claims 1 and 2, characterized in that the layer of wood-plastic material is formed by stacking pre-fabricated plates of wood-plastic material. 4. A method according to claims 1 and 2, characterized in that the layer of wood-polymer material is formed by pouring a mixture of a thermoplastic polymer binder and wood particles into the mold. 5. The method according to claims 1 to 4, characterized in that wood particles are placed between additional upper and lower horizontal layers of wood-polymer material containing 5-30% of a binder. 6. A method according to claim 5, characterized in that the horizontal layers are formed by stacking pre-fabricated wood-plastic plates. 7. The method according to claims 1 to 6, characterized in that in the preparation of wood-polymer material, before mixing with a binder, 1 to 5% of their weight formic or acetic acid is introduced into the crushed wood particles. 8. The method according to claims 1 to 7, characterized in that in the preparation of wood-polymer material, plant fibers are used as wood particles.
Hello everyone!
We have a lot of interesting plastics for decorative 3D printing. Today we will tell you about a new product - Wood from FiberForce. The price of the coil is 0.5 kg. - 3500 rubles.
FiberForce was founded in 2013 in Italy. In addition to ABS and PLA, FiberForce produces several types of special plastics, in particular FiberForce Carbon , which we have been supplying to Russia for a long time and which has proven itself
The indisputable advantage of these plastics is that they do not cause problems when printing, and you immediately get ready product imitating the color of metal or wood.
For example ESUN eAfill or eCopper.With these plastics, it is worthwhile to be more careful about setting the printing parameters. Incorrect parameters can lead to clogged nozzle. To "open" the filler, sometimes additional processing of the product after printing may be required.
FiberForce Wood belongs to the second type of decorative plastics. The plastic is based on conventional PLA filled with wood dust.
The bar is rough to the touch, with an interesting matte color of light wood.
The recommended temperature of the nozzle for printing is about 200 degrees, the table is 50-60 degrees. Although plastic adheres well to printing platforms that do not have heating. The main thing is not to forget to turn on the fan to blow the model =)
When printed, the plastic smells very nice of fresh sawdust.
Unlike the similar LAYWOO-D3 plastic, Fiber Wood does not change its color when the printing temperature changes, does not clog the nozzle and is very stable when printing.
LAYWOO-D3 - only managed to print stably using nozzles large diameter(from 0.8).
After 40 minutes of printing, we get such a nice typewriter)
The surface of the products looks very nice. Due to the dullness of the material, layers are almost invisible.
Surprisingly, the inside of our jar still smells like wood =)
FiberWood products are excellent for skinning and processing.
Outcomes
The main advantage of FiberWood from Fiber Force is that, unlike other similar materials with which we have printed, the risk of nozzle clogging is minimized. And all thanks to the optimal (low) wood dust content. This decorative plastic did not bother us and performed well in printing. Despite the fact that the basis of Fiber Wood is PLA plastic, it is excellent sanding, cutting and processing. This turned out to be a nice plus.
It's great for creating decorative elements, art objects or everyday objects "under the tree".
22.05.2015
Plastics from wood pulp (MDP) are produced by piezothermal treatment in molds that provide parts of the required configuration.
Materials. For the manufacture of wood press masses different types lump veneer with a thickness of 0.5-1.8 mm, humidity up to 12%, waste wood laminated plastics, waste woodworking industries - shavings and sawdust are used. Wood waste should not contain inclusions of bark and rot, and chipboard waste is cut into lengths up to 120 mm for the possibility of loading them into the crusher.
Bakelite varnishes SBS-1 and LBS-3, phenol-formaldehyde resin SFZh-3011 and phenol alcohols B and C are used as binders in the manufacture of press masses. The concentration of bakelite varnish before impregnation should be 43-45%, and phenol-formaldehyde resin 28-35%. Mineral oil, oleic acid, dyes, aluminum powder, silvery graphite, copper powder, etc. are used as additives that improve the properties of MDP products.
Technological process of TIR production. The technological process of MDP production consists of the following operations: preparation of conditioned wood particles, preparation of a working solution of a binder, dosing and mixing of wood particles with a binder and a modifier, and drying of the mass.
The peculiarities of the technological process for the production of MDP are associated with the type of wood waste used; in the manufacture of a press mass from sawdust (Fig. 106, a), they are sieved on a vibrating sieve with 10x10 mm cells for coarse fraction and 2x2 mm for fine fraction. Conditioned particles enter the dryer, where they are dried at 80-90 ° C to a moisture content of 3-8%. For drying, drum, belt and aerial dryers are used.
When lump veneer and chipboard wastes are used as raw materials, the technological process includes the operation of crushing wood in crushers (Fig. 106, b). To grind veneer, hammer crushers are used, for example, DKU-M. The veneer is crushed with knives and hammers mounted on the rotor of the machine. As they are crushed to the desired fraction, the particles are thrown out through a replaceable sieve and removed by pneumatic transport into the hopper. As a result, needle-shaped wood particles are formed with a length of 5-60 mm, a width of 0.5-5 mm, and a thickness of 0.3-2 mm. For crushing chipboard waste, a S-218 hammer crusher is used, crushing and sorting wood particles. The length of the particles after crushing is 12-36 mm, the width is 2-7 mm, the thickness is 0.5-1.2 mm. Particle sizes depend on the purpose of the MPE.
Wood particles with a binder are mixed in worm-blade mixers, and sawdust - in mixer-runners. The rollers of the runners, when moving along the layer of sawdust, crush them into fibers, which further provides increased physical and mechanical properties of MDP products. Wood particles and binder are dosed by weight. They are mixed by feeding wood particles in portions of 80-100 kg. The temperature of the impregnating solution, depending on its viscosity, is 20-45 ° C. The duration of mixing in worm mixers depends on the type of particles. Sawdust, shavings and veneer particles are mixed within 10-30 minutes, and chipboard particles - 15-20 minutes. The amount of dry resin in MDP should be 25-30% and 12-15%, respectively). The duration of mixing in jogging mixers is 30-40 minutes, and the dry resin content in the press mass is 25-35%.
Modifiers are fed into the mixers after loading the impregnating solution in the following amount,%: oleic acid 0.8-1.5, urotropin 1-3, dyes 2-5, graphite 2.5-10, aluminum powder or copper powder 1.5- 3, mineral oil 10-20.
Drying of the press mass is carried out at 40-50 ° C for 30-60 minutes to a moisture content of 5-7%. For this, the same units are used as for drying raw wood particles.
Technological process for the production of MDP products. For the manufacture of products, MDP can be used in the form of a free-flowing mass or in the form of a briquette obtained as a result of its preliminary compaction. The use of briquettes makes it possible to dose MDP more accurately, to reduce the volume of the loading chamber of the mold by 2-3 times, and to speed up the preheating process. Briquettes with a shape corresponding to the shape of the product (cylinders, parallelepipeds, etc.) are made in special briquetting presses or molds. Briquetting is carried out under a pressure of 20 MPa. At temperatures up to 25 ° C, the holding time under pressure is 1 min, at 50-60 ° C - 0.5 min.
To shorten the pressing cycle of MDP products, it is preheated. At 60-70 ° C, heating is carried out for 30-60 minutes, and at 140 ° C - up to 5 minutes. The most uniform heating is achieved in the HDTV field. Convective, induction and other types of heating are also used.
MDP products are manufactured by hot pressing in hydraulic presses in steel molds closed type... Pressing is carried out by direct and injection methods (Fig. 107). In direct compression, the pressure acts directly on the mass in the mold cavity. During injection molding, MDP flows under pressure from the loading cavity into the forming cavity; direct pressing is used in the manufacture of simple and large-sized products. Injection molding produces products with thin walls and a complex configuration. In the process of pressing, MDP heats up, softens, compresses, spreads in the cavity of the mold, and hardens.
The pressure during pressing of MDP with low fluidity depends on the configuration of the parts and the pressing method. With direct pressing of parts with a straight contour, it is equal to 40-50 MPa. During injection molding of parts with a figured contour in the process of pressing the press mass into a mold, the pressure is 80-100 MPa, during pressing - 40-50 MPa.
The temperature of the mold during direct pressing is 145 ± 5 ° С. The pressing time depends on the wall thickness of the product. For products with a wall thickness of up to 10 mm, when the matrix and punch are heated, it is equal to 1 min / mm, when only the matrix is heated, it is 1.5-2 min / mm, for products with a wall thickness of more than 10 mm, it is 0.5 and 1 min, respectively. /mm.
during injection molding, MDP is first compacted at a mold temperature of 120-125 ° C for 1-2 minutes. The mass is pressed into the mold at the same temperature. The end of this pressing period is determined by the moment the pressure starts to drop. Pressing is carried out at 145-165 ° C for 4 minutes. After the end of pressing, the products are cooled.
Products with a large contact surface with the mold are cooled with it to 40-60 ° C. Thin-walled products are cooled in a clamped state in special devices under a pressure of 0.2-0.3 MPa. Parts of simple configuration and parts, to the dimensions of which do not impose high requirements, are cooled in a free state.
Mechanical processing of MDF products consists mainly in the removal of flash and sprues. Additional machining in order to change the shape and size of parts is performed on metal-cutting machines.
In the production of 1 ton of MDP, the following is consumed: dry wood 1.8-2 m3, resin 600 kg, ethyl alcohol 340 l, steam 2 tons, electricity 70 kW * h.
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