Details You can cut and drag each of them manually, but this technique is very imperfect: it takes a lot of strength, and it is impossible to get two absolutely identical products. Therefore, in this material you will learn how to make the casting of plastics at home.
What can we need
For its own molding of plastics, we do not need any special tools or materials. Pretty model, a kind of matrix, we can make almost anything from metal, cardboard or wood. But regardless of which option you chose, in any case it is necessary to impregnate with a special solution before the start of work. It is especially true for wood and paper, because they actively absorb moisture and to prevent this process, we need to fill the pores, preferably liquid wax.
Silicone.
If we stopped at this option, you should buy it with the smallest viscosity - it will contribute to the best cutting part of the part. Of course, the results will be more accurate. There is a great many varieties in the modern market, and it doesn't make sense to compare them: we do not have time for it or the opportunity. We can only say with confidence that the sealant for cars is ideal for coating, preferably red. Pouring plastic at home will be much easier.
We are determined with injection molding
Honestly, the materials for casting exists even more than silicone varieties. Among them there are liquid plastic, and ordinary gypsum mixed with PVA glue, and even polyester resin. Some less popular substances are used for cold welding, light-spirited metals, and so on. But in our case, we will be based on some other characteristics of substances for casting:
- The term of their work.
- Viscosity.
Regarding the first point, it means the time, during which we can carry out manipulation with another unweathered material. Of course, if the manufacture of plastic products occurs in the factory conditions, then two minutes will be more than enough. Well, we do this at home, you need at least five minutes. And if it happened so that suitable materials You could not get it, then they can be replaced with a simple epoxy resin. Where to look for her? In auto shops or in stores for fans of aircraft modeling. In addition, such a resin is often found in ordinary shopping stores.
Making a split form
This ideal is suitable for pouring plastic with their own hands, because it is possible to pour unusual types of resins. A small cunning of such a technique can be considered that at the preliminary stage, the entire surface of the model needs to be treated with silicone, and then after the material solidifies the entire material, the matrix can be trimmed. After that, we remove its "insides" that will be useful to us for further casting. In order, we came up with the form, you should apply a three-millimeter layer of sealant, after which we just wait until the material hardens - usually it takes two hours. In this case, apply it preferably a tassel. Applying the first layer, we must try to fill with the material all irregularities or voids, so air bubbles subsequently not formed.
How is the casting process
First step.
We take a form for casting and carefully clean it - it should be dry and clean. All remnants of the material remaining after preliminary procedures must be removed.
The second step.
If there is a need, we can somewhat change the color of our composition: for this you only need to add one drop of paint into it, but in no case is not water (in liquid plastics to them personal hostility).
Third step.
There is no need for the degassing of our injection molding. This can be explained by the fact that the casting of plastics at home initially provides for the relative shortness of its "life". At the same time, in order to extract air bubbles from small-sized products, it is necessary only to carry them out after infusion.
Fourth step.
We thoroughly mix all the necessary components and pour it into the shape of the template slowly, thin jet. This should be done until the mixture will fill the entire volume and some more share of the channel for casting. And soon, when the degassing procedure occurs, the volume of this material will significantly decrease and will become as we need.
And the last advice: in order for the quality of the model to be high, cool the template is needed gradually, slowly. So, observe all instructions and everything will succeed!
Ecology of consumption. Right and technique: People learned to turn the waste treatment of natural materials into products, ahead of these materials by properties. From articles you will learn about a completely new material - a wood-polymer composite or DPK.
The last 40 years of industry development can be called "era combined Materials" Modern equipment and technologies allow you to connect, it would seem incompatible: wood, concrete, plastic, paper, metal. All of them are mixed, diffusively, they are melted with one goal - to get a new product that combines the best properties of several source materials. So, among other new products we saw " liquid tree».
What is a "liquid tree"
Speaking by technical language, this is an extruded wood-polymer composite (DPK). This means that the wood component is canned with plastic. In such a combination, the material takes the best properties:
- From wood - compressive strength, impact resistance, elasticity. At the same time, the wood component is almost free - any waste, crushed in flour, go into the course.
- From plastic - corrosion resistance, flexibility, processing accuracy. The polymer envelops wood particles and eliminates the main drawback of the tree - destructive reactions with water. The polymer in this technology is 90% secondary plastic, i.e. recycled waste.
The technological process is easy to understand, but quite complicated for execution. The polymer (plastic) is mixed in a certain proportion with wood flour and heated so that it melted. Then form in extruder, on rollers or in molds and cooled. At various stages, about 10 different additives are mixed into the mass - plasticizers, catalysts, hardensors and others. All the details of the manufacture - the grade of wood and plastic brand, the proportions of the mixture, additives, temperature modesAs a rule, make up a production secrecy. It is known that all ingredients can be purchased in a free sale, and for wood flour, the bamboo, larch and other robust breeds of the average price category are predominantly choose.
For the manufacture of DPK, special multi-stage production lines are created. They consist of a variety of devices and controllers. Collect such a machine with your own hands in the garage, unfortunately, will not work. But you can purchase a ready-made production line.
Products from DPK.
Currently, the product range is incomplete, since the material is relatively new and its properties to the end are not studied. However, several of the most sought-after positions can be mentioned now.
Terraced board or decong
It is up to 70% of all demanded products from DPK today. Most of the supplied production lines are focused on the release of this board, since this is the only alternative to the tree. The board consists of a perimeter frame, the rigid ride inside and has a puzzle fastening system. Different colors are offered.
Benefits Before traditional material: From the tree, the DPK board is beneficial to solid processes and the best physical indicators (strength, flexibility, processing accuracy). Many species dPK boards Released bilateral - with the reliefs of the wood array and ribbed cutting.
DPK terraced board on video
Facing facade panels or plaquene
By and large, they can be correlated with vinyl siding - the principle of installation and the structure of the panel they are very similar. But the DPK panel is much thicker and tough, respectively, has a greater weight and the best physical properties.
Advantages over traditional material: a more durable and durable facade, sinuses in the panels and thick walls are better kept warm and absorb noise.
Fences, fences, perilla, balustrades
Molds of small architecture from "Liquid Tree" for decorative finish Exterior and landscape. Have a good bearing capacity and suitable for intensive operation (in crowded places).
Such products were made to perform from wood (short-lived and requiring care) or concrete (heavy, cold and not always reliable). Wood-composite forms make national teams, and all the details are designing in advance. There remains on the spot only to assemble them with the help of a grinder and screwdriver. Such a fence does not require a powerful foundation, constant coloring. In case of damage to the site or structure element, it can be easily replaced by making an additional number of parts.
The overall advantage is the absolute insensitivity to atmospheric wear (moisture, frost, overheating in the sun), insect, fungi and abrasion.
The overall drawback is relatively large oscillations when heating and cooling. The expansion of the DPK terrace board can be up to 6 mm per 1 m (with gradual heating to +40 ° C).
Prices for facade panels from Liquid Tree
| Name | Manufacturer | Characteristics | Price 1 m 2, y. e. |
| Duo Fuse FPS-22 | Belgium | 2800x220x22 mm, PVC | 35 |
| "Multiplast" | Russia | 3000x166x18 mm, PE | 20 |
| Rindek. | Russia | 3400x190x28 mm, PVC | 22 |
| Multideck Chalet. | China | 2900x185x18 mm, PE | 17 |
| Cm Cladding | Sweden | 2200x150x11 mm, PVC | 28 |
| ITP ("INTEKHPLAST") | Russia | 3000x250x22 mm, PVC | 26 |
| Dortmax. | Russia | 4000x142x16 mm, PE | 18 |
How to choose a terraced DPK board
Any kind of "liquid wood" is made of wood flour, the composition of which is not so important. But the composition of the polymer, which is added to it may be crucial:
- Polymer based on polyethylene. Easier and cheaper in production. Contains a greater amount of sawdust, due to which it is cheaper analogs. Prone to UV radiation (without additives).
- Polymer based on PVC. More resistant to temperature drops, ultraviolet, large fire safety. Durable 2 times compared with other compositions.
By the type of profile, terraced boards are divided into two types:
- Forty. Consider significant shock loads. It is well suited for places with a large passability - summer cafes and verandas, decks of ships, embankments and piers.
- Hollow. Have low weight. Suitable for terraces of private houses.
By type of connection board, DPK are divided into:
- Suture. Mounted with a gap of 3-5 mm and provide a good removal of water. Mashed metal or plastic cleans.
- Seamless. Create a solid durable surface by mutual clutch. Must with self-drawing, clemmers are not required. Suitable for summer sites of a cafe - small things, heels, etc. do not fall into the gaps, etc.
By type of anti-slip or processing:
- Treated with brushes ("Brashring" from English. Brush - brush, brush). The surface created by a metal brush (artificial aging).
- Grinded. The surface is processed by the emery web.
- Embossed. Typically, executed in the structure of the tree. Good decorative ViewBut in the passable places the drawing is grieving and it becomes noticeable.
- Co-extrusion. The upper layer is performed from high strength composition and is structured during the extrusion of the board itself.
- Co-extrusion with deep embossing (from English. EMBOSSING - embossing). Embossing on the upper layer imitates the valuable wood species.
To pay attention regardless of the type of board selected:
- Height Ryube. It depends on the strength of the board.
- The number of ribbiness. It affects the flexural strength - than them more, the higher the strength.
- Wall thickness. Thin walls (2-3 mm) do not keep loading loads.
- Width of the board. The wider the board or panel, the faster and easier to install and less will be fixed.
Video - How to choose a terraced DPK board
It is absolutely possible to accept these tips in relation to facade panels And other DPK products for plane cladding.
The industry provides an average opportunity to make its choice - use the new natural material to which they go natural resources (wood, stone) or apply recycling products. Today, people have learned to convert natural material processing waste into products, ahead of these materials by properties. However, the choice remains beyond a person - either dispose of garbage, acquiring the DPK, or create it more and more, giving preference natural materials. Published
In this article we will tell how to make a popular construction material Under the name of the liquid tree with their own hands, as well as we describe all its advantages.
Any homework knows that wood products are afraid of negative impacts of a variety of operational factors, which reduces their service life. At the same time, the tree is loved by many people and professional builders. It is environmentally friendly, looks great, charging a person with positive energy, has many other advantages.
Liquid wood product
For these reasons, experts tried quite a long time to come up with a natural wood substitute, which would be visually and physical properties Not different from the tree, surpassing the last on its quality and resistance to influence natural phenomena. Studies ended with success. Modern chemical industry was able to create a unique material - a liquid artificial tree. It literally broke into the construction markets of the whole world. Now such a tree is sold under the DPK abbreviation (wood-polymer composite). The material you are interested in is made of the following components:
- Crushed wood base - essentially processing waste natural tree. In one or another composite, they can be contained from 40 to 80%.
- Thermoplastic chemical polymers - polyvinyl chlorides, polypropylene and so on. With their help, the wood base is collected into a single composition.
- Additives, called additives. These include colorants (staining the material into the required shade), lubricators (increase the resistance to moisture), biocides (protect products from mold and insect pests), modifiers (preserve the form of the composite and provide its high strength), foaming (allow you to reduce the mass of the DPK ).
These components are mixed in certain proportions, heated is strongly heated (as long as the composition does not become liquid), the polymerization of the mixture is made, and then it is fed into special forms under high pressure and cooled. As a result of all these actions, a composition is obtained that has flexibility and excellent corrosion resistance, elasticity and impact resistance. And the main thing - the DPK has the magic aroma of natural wood, as well as the color and texture, identical to the present tree.
We hope that from our short review you understood how the liquid tree is produced, and figured out what it is. Described wood and polymeric products are characterized by a number of operational advantages. We present the main of them further:
- increased resistance to the damage to the mechanical plan;
- resistance to temperature drops (operating products from the DPK can also be +150 ° C, and at -50 °);
- high moisture resistance;
- ease of self-processing and installation (for these purposes, use a tool to be operated with natural wood);
- long service life (minimum 25-30 years);
- large selection of color solutions;
- resistance to fungus;
- easy maintenance (composite is easy to clean, it can be cycled, vapor, painted in any color).
Decoration from woodoplastic
An important advantage of the voplastic is that it has a completely affordable cost. This is achieved through the use of recycling products during the production of DPK products (crushed plywood, sawdust, chips). Disadvantages in the material under consideration are difficult to find, but they are. And how without it? There are only two minuses at the vapoplastic. First, when using it in residential rooms it is necessary to equip high-quality ventilation. Secondly, the DPK is not recommended to be used in cases where high humidity and high air temperature are constantly present at the same time.
Special characteristics of a composite of wood and plastic allow you to make various from it construction products. This material goes to the production of outdoor siding, smooth, hollow, corrugated and solid decong (in other words, a terraced board). From the DPK make gorgeous balustrades, coupling railing, reliable fences, luxurious arbors and many other designs. The trees will allow you to luxuriously equip interiors in a residential room and make your country plot truly beautiful.
The cost of the composite described depends on which polymer is used for its manufacture. If the manufacturer makes the DPK from polyethylene raw materials, the price of finished products will be minimal. But it is worth noting that such products do not have resistance to ultraviolet. But polyvinyl chloride polymers give the leafoplastic high resistance to fire and UV rays, and also make it very durable. Products from DPK (in particular, Decing) is customary to divide on seamless and seams. The first are mounted without curvatures, screws and other hardware. Such boards simply adhere to each other by forming a solid solid surface.
Wood-plastic material
But for the installation of products with seams, it is necessary to use plastic or metal fasteners (most often in the role of such a blessing). DPK-slabs or boards can be hollow and full. For arrangement, the veranda of private houses is better to use products with voids. They are light, work with them yourself very simple. Full-time vest plastic, which is able to withstand essential loads, is more suitable for laying in in public places (Naberezhnye, summer restaurants and bars, ship decks), where there is a high passability of people.
When choosing boards from the DPK, pay attention to the thickness of their walls (it should be at least 4-5 mm), the height of the rigidity ribs (than they are higher, the more reliable in operation will be products) and their number (the more ribs, the stronger it turns out design).
It should also be reasonably choosing the width of composite panels and boards. Here you need to understand one moment. C.all wider products you buy, the easier it will work with them, because for mounting such boards will need less than the fasteners . Several Yet useful Soviets For you. Specify from the sellers, from which sawdust was manufactured by the DPK. If the manufacturer used coniferous wood for these purposes, better look for another material. Why? For the reason that composites on a conifer-based basis are considered fire hazard. Yes, and the strength characteristics of such products leave much to be desired. The DPK on the basis of waste from the processing of deciduous trees is deprived of these shortcomings.
In cases where the bright bodies or plots, the operational reliability of products will be well visible on the composite panels (boards, plates). Most likely, the manufacturer used the wood flour of low quality, and, moreover, badly grinding. Such panels tend to have a small waterproof rate. It is impossible to use them on the street. The presence of inhomogeneous color (divorces, well-visible shades transitions) on its insufficient quality of the DPK.
And now the most interesting. If you wish, you may well at home to make a decent analog of DPK. Homemade vest plastic is made from sawdust and conventional PVA-glue and is used to restore parquet boards, repairing laminate on the floor, restoration of others wooden coatings. It can also be used for the manufacture of coarse flooring for floors in the arbors and in the premises of the auxiliary.
CamPositic material from sawdust and glue
DPK is done with their own hands according to the following scheme:
- Grind wood sawdust in a coffee grinder or hand-made kitchen mill to dust condition.
- Add to crushed PVA glue (30% proportions - 30%) and mix these components until you get a mixture with pasta consistency.
- In the made composition pour dye (it is recommended to use additives used for ordinary water-emulsion paint). Mix everything again.
So you made homemade vestovers! Boldly fill in the composition of the hole in wooden polits. After soaring the DPK, the renovated plot will only be altered using emery with small grain. The composition made by their own hands can also be applied to arrange new floors. Collect, make homemade DPK in the desired quantities and pour them the formwork design. The thickness of homemade boards in this case should be equal to at least 5 cm. Dress!
- Description I. chemical composition
- Polymer and Tree ratio
- Benefits of material
On construction and in the manufacture of furniture, new high-tech materials with improved properties are applied, compared with the usual of the same class, and their price is lower. One of these materials is a wood-polymer composite (DPK). Now it is widespread, which is associated with accessibility and low cost. It is cheaper than ordinary tree, but has the same strength.
In the manufacture of the composite use natural wood and a polymer that does not harm human health. Usually, the DPK is obtained by casting method, which significantly increases its strength.
Composite can be used when laying flooring. It is used when installing the railings on open terraces, in gazebos, in balconies, because resistant to temperature drops, any precipitation, mechanical exposure. This makes the DPK universal. The material has a beautiful structure.
DPK is distributed in the USA, where it is actively used in the construction of cottages. Production technology, characteristics It is important to know if you chose this material. If you know the features of the process of manufacturing a liquid tree, then you can make a composite with your own hands.
Description and chemical composition
Polymer composite, which is called a liquid tree, is an artificial material obtained by mixing wood and monomer. In the process of manufacture, an extrusion is taken forming a polymer. Similar method made a polymer board, the strength is superior to the usual tree, but a little inferior ceramic tiles. The boards themselves acquire the form in the casting process.
The "liquid tree" is produced by adding bonding polymers to chips: polystyrene, polyethylene, polypropylene and polyvinyl chloride. The name "Liquid Tree" DPK received due to flexibility and plasticity.
The "Liquid Tree" is used in the production of genital boards, siding, pipes (for water supply, sewage), furniture.
The chemical composition of the DPK includes only 3 components:
- Small wood particles (chips, sawdust, crushed wood, abroform, in cheap models come across the cake from sunflower seeds, crushed plywood). The number of additives 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 greatly improve technical properties, appearance (dyes, varnishes). The volume of these additives is 0.1-4.5% of the total mass.
Polymer and Tree ratio
The proportions of the ratio of polymer and wood can be different. The selection is carried out with what technical indicators of the DPK are required.
Tree (Abroform) to the polymer belongs as 2: 1. This ratio gives the DPK of the Wood Properties - the mass will contain more fibers of the tree. Boards from such material will swell from moisture, which significantly reduces the service life in the humid climate. For the middle strip and south of Russia, it will be 5-10 years old. The DPK is relatively fragile, which limits its application, but the building material has a beautiful texture of the tree and the "corrugated" surface.
The ratio of wood to the polymer, like 2: 3, significantly worsens the appearance of the DPK Board, which limits the use of boards in decorative purposes. On the touch, the board resembles ordinary plastic, and the surface becomes smoother (sometimes slippery).
If the wood-polymeric composite has the ratio of the fibers of the tree (Abroform) to the polymer 1: 1, the board acquires optimal characteristics. The texture is beautiful, with a rough surface, non-slip. The casting process is simplified: it is not necessary to warm the components to the desired temperature. Preparation of DPK this way does not transmit the properties of the tree material: it does not absorb moisture, does not swell, relatively durable in use.
The liquid tree is poured into special forms that provide for the presence of spikes and grooves for fastening boards.
Benefits of material
The DPK is resistant to the effects of ultraviolet: it is not cracking, not deformed. It does not change its structure at low air temperatures, the impact of moisture, acids and other negative environments.
The material is resistant to mold, insects are not breeding in the DPK, it is not bait for mice, rats and other rodents. For greater stability, it can be covered with a special polymer film.
Another plus is higher strength (it allows you to withstand more than 5 c per 1 m 2). This makes it possible to place any heavy furniture on the boards.
Liquid wood - flexible material that is easy to process. It can be cut, overshoot. This is taken into account in the production of polymers or in the process of casting.
Liquid tree is an environmentally friendly material, since the used abroforms and the polymer are not distinguished poisonous substances And do not pose a danger to a person. DPK is not a fuel and does not support burning.
Is it possible to make it yourself?
You can make a "Liquid Tree" (Abroform) at home, with DPK, made with your own hands, will have the desired characteristics. Billets are suitable for restoration works (furniture), rough flooring for auxiliary premises, arbors, terraces.
To make a liquid tree, you need to take woody sawdust and chop them with homemade mills or coffee grinding. PVA adhesive is added to the mixture (the ratio of sawdust and glue 70:30). The resulting mixture should be thick. In order for the material to have the desired color, it is recommended to add the paint (enamel) of suitable color.
The resulting mass is an analogue of the DPK. The material can be applied to damaged parquet areas, laminate, furniture.
If you pour the floor with such material, then it is necessary to make a formwork for it, and the mixture itself is prepared in the desired volume. Then you can proceed to the fill. Recommended thickness of the future board - 50 mm.
480 rub. | 150 UAH. | $ 7.5 ", Mouseoff, Fgcolor," #FFFFCC ", BGColor," # 393939 ");" Onmouseout \u003d "Return nd ();"\u003e Dissertation period - 480 rub., Delivery 10 minutes , around the clock, seven days a week and holidays
Savinovsky Andrey Viktorovich. Obtaining plastics from wood and vegetable waste in closed molds: the dissertation ... Candidate of Technical Sciences: 05.21.03 / Savinovsky Andrei Viktorovich; [Place of protection: Ural State Forestry University] .- Ekaterinburg, 2016.- 107 p.
Introduction
Chapter 1. Analytical Overview 6
1.1 Wood-composite materials with synthetic binders 6
1.2 Lignoral and Piezotermoplasty 11
1.3 Methods for modifying wood particles 14
1.4 lignin and lignorant complex 19
1.5 cavitation. Cavitational processing of vegetable raw materials 27
1.6 Bioactivation of wood and vegetable particles enzymes .. 33
1.7 Selection and Justification of Research Directions 35
Chapter 2. Methodical Part 36
2.1 Characteristics of the starting materials 36
2.2 Meeting Methods 41
2.3 Preparation of bioactivated press raw materials 41
2.4 Production of DP-BS 41 samples
2.5 Cooking Snake Press Raw Materials for Plastic 42
Chapter 3. Obtaining and studying the properties of wood plastics without binding using modifiers 43
Chapter 4. Influence of the chemical modification of wheat husks on the properties of RP-BS 57
Chapter 5. Obtaining and studying the properties of wood plastics without binder using bioactivated press raw materials 73
Chapter 6. Technology for receiving DP-BS 89
6.1 Extruder Performance Calculation 89
6.2 Description of the production process of production 93
6.3 Cost estimate finished products 95
Conclusion 97.
Bibliography
Introduction to work
Relevance of the research topic. The production volumes of wood and vegetable raw materials processing are constantly increasing. This increases the number of different waste of wood processing (sawdust, chips, lignin) and agricultural plants (straw and sheath of cereals).
In many countries, there are production of wood composite materials using synthetic thermosetting and thermoplastic organic and mineral binders as a polymer matrix, as fillers - crushed waste of plant origin.
Known the possibility of obtaining wood composite materials with flat hot pressing from woodworking waste without adding synthetic binders, which were called Piezotermo-Plastics (PTP), ligno-household wood plastics (LoudP). It notes that the initial press compositions have low indicators of plastic viscous properties, and the resulting composites have low indicators of physicomechanical properties, especially water resistance. And this requires the search for new ways to activate the lignin-carbohydrate complex.
Thus, work aimed at the use of wood and vegetable waste without using synthetic binders to create products are relevant.
The work was carried out on the task of the Ministry of Education and Science of the Russian Federation, Project No. 2830 "Getting Wood Plastics from Tree Biomass and Agricultural Plant Waste" for 2013-2016.
Purpose and task of work. The aim of the work is to obtain plastics from wood (DP-BS) and agricultural waste (RP-BS) without adding synthetic binders with high operational properties.
To achieve the goal, it is necessary to solve the following tasks:
Investigate the process of forming a DP-BS and RP-BS based on wood (pine sawdusts) and vegetable (wheat husks) waste.
To study the influence of chemical modifiers, as well as technological parameters (temperature, humidity) on the physico-mechanical properties of the DP-BS and RP-BS.
Determine the rational conditions for obtaining DP-BS and RP-BS from wood and vegetable waste.
Establish the effect of bioactivation of press raw materials active il on physical
co-mechanical properties of DP-BS.
The degree of development of the topic of study. The analysis of scientific and technical and patent literature showed a very low degree of development of issues related to the laws of formation of the structure and properties of wood plastic without a synthetic binder.
Scientific novelty
The DSC methods are established kinetic patterns of the process of the formation of DP-BS and RP-BS (activation energy, pre-exponential factor, reaction procedure).
The influence of chemical modifiers (hydrogen peroxide, urotropin, isomethyltetrahydrofthali anhydride, cavitation lignin, hydrolysis lignin) on the speed of the DP-BS formation process and RP-BS is established.
Kinetic patterns of obtaining DP-BS using bioactivated wood waste were obtained.
Theoretical significance The work is to establish patterns of influence of a number of modifiers and humidity of press-raw materials from wood and agricultural waste on the physico-mechanical properties of the DP-BS and RP-BS.
Practical significance The work is to use renewable raw materials and experimental proof of the possibility of obtaining DP-BS and RP-BS with elevated physical and mechanical properties. A recipe for DP-BS and RP-BS has been proposed. DP-BS products have low formaldehyde emissions.
Methodology and research methods. The work used the traditional methodology of scientific research and modern methods Studies (differential scanning calorimetry, IR Fourier spectroscopy, PMR 1 H).
The defense is taken out
Results of the study of thermocinetics of the formation of DP-BS, RP-BS and the influence of modifiers and humidity on this process.
The patterns of the formation of the properties of the DP-BS and RP-BS in closed molds under the influence of temperature, moisture content of press raw materials and its chemical modification.
The degree of reliability of research results Provided by multiple repetition of experiments, using the methods of statistical processing of the obtained measurement results.
Approbation of work. The results of the work are reported and discussed at the VIII International Scientific and Technical Conference "Scientific Creativity Youth - Forest Complex" (Ekaterinburg, 2012), the IX International Scientific and Technical Conference "Scientific Creativity Youth - Forest Complex" (Ekaterinburg, 2013), International Conference "Composition Materials on wood and other fillers "(Mischi, 2014).
Publications. According to the dissertation materials published 12 articles, including 4 articles in publications recommended by VAC.
Workload
The thesis is preserved on 107 pages of machine-visiting text, contains 40 tables and 51 drawings. The work consists of introduction, 6 chapters, conclusion, a list of references, including 91 references to domestic and foreign work.
Lagnogogo-water and piezotermoplasty
Lagnogogo-water and piezoteroplasty. These materials are manufactured from wood sawdust or other vegetable raw materials with high-temperature handling of the mold without entering special synthetic binders. The technological process of the production of ligno-household wood plastics consists of the following operations: preparation, drying and dosing of wood particles; Forming a carpet, its cold subressive, hot pressing and cooling without pressure removal. In preparing the mold, wood particles are sorted, then the fraction of greater than 0.5 mm is further crushed, the conditioned sawdust is entered into the dryer, and then into the pallium machine. The carpet is formed on pallets coated with a layer of talc or anti-adhesion fluid. First, the finished carpet is fed to the press for a cold subressive, which lasts for 1.5 minutes at a pressure of 1-1.5 MPa, after which it is sent to a hot pressing at a pressure of 1.5-5 MPa and a temperature of 160-180 C. Pressing plates 10 mm thick for 40 minutes.
Under the influence of temperature, partial hydrolysis of wood polysaccharides and the formation of organic acids, which are catalysts that contribute to the destruction of the ligno-household complex are occurring. Formed chemically active products (lignin and carbohydrates) interact with each other when pressing. As a result, a more dense and durable material is formed than wood.
Raw materials for the production of ligno-breed wood plastic are obtained by the processing of wood coniferous and hardwood. Along with sawdust, machine chips, shot, to obtain plastic, the bark can be used in a mixture with wood, crushed forest waste and some weighted agricultural waste. The impurities in the raw materials of partially rotten wood improve the physicomechanical properties of ligno-household plastics.
Compared to the chickens, ligno-house plastics have a number of advantages: they are not exposed to aging due to the destruction of organic binder and their strength indicators are not reduced over time; When operating there are no toxic secretions in environment. The essential disadvantages of the production of ligno-car plastics are the need for powerful pressing equipment and the duration of the pressing cycle.
It is noted that under the influence of pressure and temperature, the crushed vegetable raw materials acquires the ability to form durable and solid dark color material, which can be molded. This material was called Piezoteroplasty (PTP).
The initial raw material, along with sawdust, can serve a crushed wood of coniferous and hardwood, linen and hemp fire, reed, hydrolysis lignin, edain.
There are several ways to obtain PTPs who have undergone profound elaboration and introduction into production, but not found further use due to high energy consumption: 1) one-step method of obtaining PTP (A.N. Minin. Belarusian Institute of Technology); 2) a two-stage method of obtaining plastics from hydrolyzed sawdust (N.Y. Skorenik, Leningrad LTA); 3) technology of obtaining ligno-carca water plastics (LUDP) (VN. Petri, Ural LTI); 4) the vapor explosion technology (Ya.a. Gravitis, the Institute of Wood Chemistry. Latvian An). Piezoteroplasty are divided into insulating, semi-solid, solid and superhard.
With an average density of 700-1100 kg / m3, piezotermic plastics made of birch sawdust have a strength of static bending 8-11 MPa. With an increase in the average density to 1350-1430 kg / m3, the strength of static bending reaches 25-40 MPa.
The high physico-mechanical properties of piezotermoplasty allow them to apply them for the manufacture of floors, doors, as well as as a finishing material. The type of wood plastics is vibroite, the technological features of which are in partial grinding of sawdust and shallow shavings on the vibro produce, stirring a thinly ground mass with water and then we get sludge. From a mixture of sludge with particles of 0.5-2 mm, a carpet dehydrated by a vacuum pump is formed in the refrigerated machine. The resulting press mass enters cold and hot pressing. The finished plates are transported to the hardening chamber, where for 3-5 hours at a temperature of 120-160 s, they are subjected to heat treatment, as a result of which their water absorption is reduced almost 3 times and more than 2 times - swelling.
Vibroite is used for black flooring, partition devices, lining of wall panels in public buildings, manufacturing built-in furniture and shield doors.
Since the 30s, many researchers were engaged in the USSR by obtaining slaughter materials in the USSR to obtain plate materials without the use of traditional binders. Works were carried out in the following directions: 1) the pressing of natural, no treated sawdust; 2) the pressing of sawdust subjected to pre-autoclave treatment with water vapor (predagrolysis) or water vapor with a catalyst (mineral acid); 3) pressing sawdust, pre-treated with chemical reagents: a) gelatinating the mold (chlorine, ammonia, sulfuric acid, etc. substances) for its partial hydrolysis and enrichment with substances with the binding properties; b) chemical polycondensation of the mold with the participation of other chemicals (Furfurol, phenol, formaldehyde, acetone, alkaline and hydrolysis lignins, etc.).
Preparation of bioactivated press raw materials
The endothermic minimum corresponds to the process of hydrolysis of the lignin - a carbohydrate complex and a lung-hydralyzable part of cellulose (polysaccharides).
The exothermic maximum corresponds to polycondensation processes, which determine the process of formation of the DP-BS. Since the process is catalyzed by acids, which are formed in the pyrolysis of wood, as well as due to the presence of resin acids contained in the composition of extractive substances - is the reaction of N-th order with auto-calm.
For wood waste with modifying additives (hydrogen peroxide, urotropin, imgf) maxima of peaks on DSC curves shifted to the left, which indicates that these compounds act as catalysts of the above processes (T1 100-120 ° C), T2 180-220 0 Accelerating the process of hydrolysis of wood polysaccharides, as well as the lignin-carbohydrate complex.
Table.3.2 shows that in the first stage with an increase in the humidity of the press, the effective activation energy (from 66.7 to 147.3 kJ / mol) increases, which indicates a greater degree of hydrolytic wood destruction. The use of modifiers leads to a decrease in the effective activation energy, which indicates their catalytic effect.
The values \u200b\u200bof the effective activation energy in the second stage of the process for a modified press-raw material with an increase in humidity varies slightly.
The use of modifiers leads to a decrease in the effective activation energy and in the second stage of the process. Analysis of kinetic equations showed that best model At the first stage of the process, the reaction of the N-order, in the second stage - N-order with auto-resistant: A 1 b 2 C.
Using the kinetic process parameters, T50 and T90 were calculated (the time required to achieve the degree of conversion 50 and 90%) for non-modified and modified press-raw materials (Table 3.3), and the curves of the degree of transformation (Fig.3.4-3.6) .
The dependence of the degree of conversion from time at various temperatures (pine, the initial moisture content of the press-raw material - 8%) Figure 3.5 - the dependence of the degree of transformation from time at various temperatures (pine, modifier - urotropin, the original moisture of press raw materials - 12%)
The dependence of the degree of conversion from time at various temperatures (pine, modifier - hydrogen peroxide, the initial moisture content of the press raw material - 12%) Table 3.3 - the time of the time of reaching the degree of conversion of 50% and 90% at different temperatures No. p / p. Degree of transformation of press raw materials With a humidity of 8% press-raw materials of 12% (modifier -1.8% H2O2,%) Press-raw fracture of 12% (modifier - 4% C6H12N4,%)
The use of hydrogen peroxide leads to the acceleration of the process in the first stage more than 4 times than when modifying the press-raw materials of urotropin. Similar pattern is observed in the second stage of the process. Under the total time of formation of DP-BS, the activity of the press of raw materials can be positioned in the following row: (unmodified press raw material) (mold-raw material modified by urotropin) (press-raw material modified hydrogen peroxide). In order to establish the effect of humidity and the content of the amount of modifier in press raw materials on operational properties DP-BS, a mathematical planning of the experiment was carried out. Previously conducted the effect of humidity of the original press-raw material on the physico-mechanical properties of the DP-BS. The results are shown in Table. 3.4. It has been established that the greater the initial moisture content of the press raw material, the less physicomechanical properties, such as bending strength, hardness, module of elasticity in bending. In our opinion, this is due to a greater degree of thermohydrolitic destruction of the ligno-carbon complex. Table 3.4 - Physico-mechanical properties of the DP-BS obtained at different moisture content of the press material
Thus, the physico-mechanical properties of the DP-BS depend on the recipe and the conditions for its preparation. So for plastic with high physicomechanical properties, it is necessary to use the following composition: Lignin content 3%, NTGFA content 4%, the initial moisture content of press-raw material and hot pressing temperature 1800c. For plastic with low water absorption and swelling values, it is required to use the composition: Lignin content 68%, NTGFA content of 2%, the initial moisture content of press-raw materials 17% and hot pressing temperature 195 C0.
Effect of chemical modification of wheat husks on the properties of the RP-BS
The depth of the thermohydrolitic destruction of the lignin of wood and vegetable raw materials depends on the type of chemical modifier used.
We spent studies of the formal kinetics of plastics show that lignin coniferous rocks (pine) has a greater reactivity than Lignin annual plants (Wheat husks). These results are consistent with the results of the oxidation of model compounds of lignin of coniferous, hardwood and lignin of plant origin. The analysis of the literature showed that the theoretical studies of the peculiarities of the transformation of wood in the enzymatic effects made it possible to develop biotechnology of wood plastics based on partial biodegradation of the ligno-carbon complex.
It is known that biotransformed wood particles substantially change their plasticity. Also, the pioneer of wood raw materials has a significant impact on the physico-mechanical properties of plastic.
Bioactivated Woodwater Treatment various species Lagno-developing mushrooms, bacteria, in our case active il, is promising for the manufacture of press raw materials for DP-BS (AI).
Initially, the patterns of the process of obtaining DP-BS (AI) were studied on the basis of wood waste using active yals (Fig. 5.1) with a different period of bioactivation. 0.5 7 days 14 days
The study of the process of forming a DP-BS (AI) by the DSC method showed that on curves w \u003d f (t) (Fig. 5.2) there are two exothermic maxima. This indicates that the process can be represented as two parallel reactions corresponding to the bioactivated and non-activated press-raw materials, i.e. A 1 B and C 2 D. At the same time, the reactions 1 and 2 are N-order reactions).
The kinetic parameters of the DP formation process of the DP-BS (AI) are determined. The results are shown in Table. 5.1. Table 5.1 - Kinetic Parameters of the Education Process of the DP-BS (AI)
At the second stages of the process of obtaining DP-BS (AI), the effective activation energy values \u200b\u200bof the activation is the same order as for wood press raw materials (see ch. 3). This indicates that this exothermic peak corresponds to non-bioactivated wood press raw materials. Using the kinetic process parameters, T50 and T90 were calculated (the time required to achieve the degree of conversion of 50 and 90%) of the modified press-raw material (Fig.5.3, 5.4).
Figure 5.3 - Turning time of the conversion of DP-BS (AI) at different temperatures (bioactivation time of 7 days) Figure 5.4 - The values \u200b\u200bof the conversion of DP-BS (AI) at different temperatures (bioactivation time 14 days)
In order to establish the effect of active yla and cavitation lignin on the physico-mechanical properties of the DP-BS (AI), a matrix of experiment planning on the basis of regression fractional mathematical planning of the form 25-1 was compiled (see Table 5.2).
As independent factors were used: Z 1 - the content of cavitation lignin,%, z 2 - the temperature of the hot pressing, C, Z 3 - the consumption of active yals,%, z 4 - the duration of the exposure (bioactivation), day; Z 5 - the initial moisture content of press raw materials,%.
Over the output parameters: density (P, kg / m3), bending strength (P, MPA), hardness (T, MPa), water absorption (B), swelling (L,%), module of elasticity with bending (EI, MPa ), shock viscosity (A, KJ / M2).
According to the experiment plan, samples were made in the form of disks and their physicomechanical properties were determined. Experimental data were treated and examined by the equation of regression in the form of a linear, polynomial 1 and 2 degrees with an assessment of the significance of factors and the adequacy of the equations that are presented in Table 5.2-5.4. Table 5.2 - the planning matrix and the results of the experiment (three-tier five-factor mathematical plan) a) hot pressing temperature and content of cavitation lignin; b) consumption of the silo mixture and pressing temperature; c) humidity of press raw materials and duration of bioactivation; d) the duration of bioactivation and the content of cavitation lignin.
The DP-BS (AI) density (AI) was established with an increase in the content of cavitation lignin in press raw materials wearing an extreme character: the minimum density of 1250 kg / m3 is achieved when the CL content is 42%. The dependence of the DP-BS (AI) density on the duration of the bioactivation of press raw materials is also extreme and maximum value is achieved at 14 days of bioactivation (Fig. 5.5V).
Evaluation of the cost of finished products
Conducted studies on obtaining DP-BS, DP-BS (AI) and RP-BS (see HL. 3,4,5) show that the physico-mechanical properties of plastic depend on the recipe of press raw materials, the type of chemical modifier and the conditions of its manufacture .
In tab. 6.1 The physicomechanical properties of plastics (DP-BS, DP-BS (AI) and RP-BS) obtained under rational conditions are presented.
From the analysis of the results obtained (Table 6.1) it can be seen that for the manufacture of products having high physical and mechanical properties, the press composition of the following composition is recommended: wood waste (Pine sawdust), modifier - hydrogen peroxide (consumption - 1.8%) Original humidity - 12%.
To increase productivity, an extrusion method is proposed that allows you to make jigging products.
The dissertation work discusses the production of plinth. To comply with the conditions defined during hot pressing in closed molds, the extrusion head consists of two parts (heated part of the head and the second - without heating). At the same time, the residence time of the press composition in the heated part of the extrusion head is 10 minutes.
To determine the annual production volume, the performance of the extruder was calculated.
For a single-screw extruder from a variable (decreasing) deep cutting of a spiral channel, the calculation of volumetric performance (q, cm3 / min) can be carried out as follows:
Here A1, B1, C1 - constant, respectively, directly and two reverse flows at a variable depth of cutting auger, cm3; Table 6.1 - Physical and Mechanical Properties of DP-BS, DP-BS (AI) and RP-BS (Summary Table) No. P / P1245 6 Indicator HumidityPress-Raw Materials,% DP-BS Modifier (AI) DP-BS RP-BS 12 % (4% -C6H12N4) 12% (1.8% -N202) CL - 3% Consumption AI-37% Humidity - 10% GL - 3% of NMHFFa-4% Humidity - 6% GL - 68% NITGFA-2, 5% humidity-17.9% humidity - 12% ch - 3% peroxide-0.06% humidity - 12% ch - 35% peroxide - 5% humidity- 12%
Bending strength, MPa 8 12.8 10.3 9.6 12.0 - 8 9.7 hardness, MPa 29 29.9 27.7 59 69 20 19 34 Module of elasticity with bending, MPa 1038 2909,9 1038, 6 732,6,154 1402 1526 1915 Water absorption,% 59.1 148 121.7 43 59 34 143 139 Blowjob,% 6.0 12 8 3 5.0 1.0 7 7.0 1 K is the geometric shape coefficient, K \u003d 0.00165 cm3; n - the speed of rotation of the screw, n \u003d 40 rpm. where T is a pitch of cutting, cm is taken t \u003d 0.8d; - the number of signs of cutting auger, \u003d 1; E - the width of the ridge of the screw, see; E \u003d 0.08d; - The coefficient of geometric parameters of the auger:
The coefficients, A, B depend on the geometric sizes of the auger. They are easy to calculate if there is a shne drawing, from which the following values \u200b\u200btake: H1 - the depth of the spiral canal at the beginning of the power zone, cm; H2 - the depth of the spiral canal at the beginning of the compression zone, see; H3 - the depth of the spiral canal in the dosing zone, see; If the sizes of the auger are unknown (with the exception of D and L, which are known from the extruder brand), then take H1 \u003d 0.13D. After that, the remaining parameters are calculated: where L is the length of the auger, cm; L0 - Schneck length to compression zone, cm; where LN is the length of the screw part of the auger, see; LN \u003d 0,5L. where і is the degree of compression of the material; І \u003d 2.1. The results of calculations on the above formulas allow you to calculate some other auger parameters.
Wood waste is sorted by vibrositis (pos.1) from large particles, then wood particles pass metal detector (pos.3). The large fraction enters the hammer crusher (pos.2) and then returns to the vibrating line (pos.1). With vibrosite, small particles are fed into the cyclone (pos.4), and then in the bunker (pos.5), from where the portion screw conveyor is supplied to the drum dryer (pos.6), wood particles are dried to a humidity of 6%. Crumpled wood waste is entered into the cyclone (pos. 7), then in the bunker of dry ground waste (pos.8) with a screw conveyor, by which they are fed to ribbon scales (pos.9).
Preparation of hydrogen peroxide solution occurs in the tank (pos.10) for mixing with water. Hydrogen peroxide is dosed using weights (pos.10). The supply of the required amount of water is regulated by the flow meter. The concentration of hydrogen peroxide should be 1.8%. Ribbon scales are supplied with the required amount of chopped wood particles into a continuous mixer (pos.12), which also flows a certain amount of solutions of modifiers. In the mixer, a thorough mixing of components is carried out, the moisture content of press raw materials should be 12%.
Then the press raw material falls into the distribution funnel (pos.13), from where it goes to the bunker (pos.14) of the finished press of raw materials. The bunker is the main buffer warehouse to ensure uninterrupted installation operation. The bunker (pos 14) is equipped with a screw dispenser (pos.15), with which the finished composition is loaded into the hopper of the extrusion unit (pos.16), with which the finished composition is supplied to the extrusion head.
The Extrusion Installation Channel (pos.17) is heated to a temperature of 1800C, the time of stay in the heated part is 10 minutes, in the unheated also for 10 minutes.
The pressed product (pos.18) is sent to the trimming stage, chosen and sorting, then enters the mechanical processing stage. After the stage of control, finished products are sent to the finished product warehouse. Figure 6.1 Technological scheme for the production of the product in the form of a Plintus DP-BS from Woodworking Waste without adding binders by extrusion
Table 6.2 presents the calculation of the annual need for raw materials for the production of plinth. The estimated annual productivity of the production line of this type of production is 1 ton. Table 6.3 - Calculation of raw materials and materials Type of raw material Cost rate (1 ton), cost 1 kg of raw materials, rub. The amount of costs for 1T products, thousand rubles. Pine sawdust 0,945 8 7,56 TECHNICAL WATER 0.048 7 0.33 hydrogen peroxide 0.007 80 0.56 Total: 8.45 The amount of costs to acquire raw materials by one ton of finished production production will be 8.456 thousand rubles. Compared to the production of this type of products from DPT, which amounted to 47.65 thousand rubles. Thus, the production of Plinth from DP-BS is economically appropriate. In the production of 50 t / g, saving for raw materials will be 1.96 million rubles.