Composite materials: what they are, properties, production and application. Rules for performing work
In this article we will tell you how you can make a popular construction material called liquid tree with your own hands, and we will also describe all its advantages.
Any home craftsman knows that wood products are afraid negative impacts various 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, charges a person with positive energy, and has many other advantages.
Liquid wood product
For these reasons, experts have been trying for quite a long time to come up with a substitute for natural wood that would visually and physical properties was no different from wood, surpassing the latter in its quality and resistance to influence natural phenomena. The research was successful. The modern chemical industry has been able to create a unique material - liquid artificial wood. It literally burst into construction markets all over the world. Now such wood is sold under the abbreviation WPC (wood-polymer composite). The material we are interested in is made from the following components:
- Shredded wood base is essentially processing waste natural wood. A given composite may contain from 40 to 80% of them.
- Thermoplastic chemical polymers - polyvinyl chlorides, polypropylenes and so on. With their help, the wood base is assembled into a single composition.
- Additives called additives. These include colorants (color the material in the required shade), lubricators (increase resistance to moisture), biocides (protect products from mold and pests), modifiers (preserve the shape of the composite and ensure its high strength), foaming agents (allow you to reduce the weight of WPC ).
These components are mixed in certain proportions, heated strongly (until the composition becomes liquid), the mixture is polymerized, and then it is fed into special forms under high pressure and cool. The result of all these actions is a composition that has flexibility and excellent corrosion resistance, elasticity and impact resistance. And most importantly, WPC has a magical aroma of natural wood, as well as color and texture identical to real wood.
We hope that from our short review you understood how liquid wood is produced and figured out what it is. The described wood-polymer products are characterized by a number of operational advantages. We present the main ones below:
- increased resistance to mechanical damage;
- resistance to temperature changes (WPC products can be used at both +150 °C and -50 °C);
- high moisture resistance;
- ease of self-processing and installation (for these purposes, use a tool that works with natural wood);
- long service life (minimum 25–30 years);
- large selection of colors;
- resistance to fungus;
- ease of maintenance (the composite is easy to clean, it can be scraped, varnished, painted in any color).
Wood plastic decoration
An important advantage of wood-plastic is that it has a very affordable price. This is achieved through the use of recycled products (crushed plywood, sawdust, shavings) in the production of WPC. It is difficult to find shortcomings in the material we are considering, but they exist. What would we do without this? Wood-plastic has only two disadvantages. Firstly, when used in living rooms needs to be equipped high-quality ventilation. Secondly, WPC is not recommended for use in cases where there is simultaneously and constantly high humidity and elevated temperature air.
The special characteristics of a composite of wood and plastic make it possible to manufacture various construction products. This material is used for the production of external siding, smooth, hollow, corrugated and solid decking (in other words, deck boards). WPC is used to make chic balustrades, elaborate railings, secure fences, luxurious gazebos and many other structures. Wooden plastic will allow you to luxuriously arrange the interiors of your living space and make your own suburban area truly beautiful.
The cost of the described composite depends on what polymer is used for its manufacture. If a manufacturer makes WPC from polyethylene raw materials, the price for finished products will be minimal. But it is worth noting that such products are not UV resistant. But polyvinyl chloride polymers give wood plastic high resistance to fire and UV rays, and also make it very durable. Products made from WPC (in particular, decking) are usually divided into seamless and with seams. The first ones are mounted without clamps, screws and other hardware. Such boards simply adhere to each other, forming a strong, continuous surface.
Wood plastic material
But to install products with seams, it is necessary to use plastic or metal fasteners (most often, clamps act as such). WPC slabs or boards can be hollow or solid. For arranging the verandas of private houses, it is better to use products with voids. They are lightweight and very easy to work with on your own. Solid wood-plastic, which can withstand significant loads, is more suitable for installation in in public places(embankments, summer restaurants and bars, ship decks), where there is a high traffic volume of people.
When choosing WPC boards, pay attention to the thickness of their walls (it should be at least 4–5 mm), the height of the stiffening ribs (the higher they are, the more reliable the products will be in operation) and their number (the more ribs, the stronger the result). design).
You should also choose the width of your composite panels and boards wisely. One point needs to be understood here. H The wider the products you buy, the easier it will be for you to work with them, because installing such boards will require significantly fewer fasteners . Several Yet useful tips for you. Check with the sellers what sawdust the WPC was made from. If the manufacturer used coniferous wood for these purposes, it is better to look for another material. Why? For the reason that coniferous-based composites are considered fire hazardous. Yes and strength characteristics Such products leave much to be desired. WPCs based on waste from processing deciduous trees do not have these disadvantages.
In cases where composite panels(boards, slabs) light veins or areas are clearly visible, operational reliability products will be low. Most likely, the manufacturer used wood flour of low quality, and, moreover, poorly ground. Such panels, as a rule, have low water resistance. They cannot be used outdoors. The insufficient quality of the WPC is also indicated by the presence of a non-uniform color on its surface (stains, clearly visible shade transitions).
Now comes the fun part. If you wish, you can easily make a worthy analogue of WPC with your own hands at home. Homemade wood-plastic is made from sawdust and ordinary PVA glue and is used for restoration parquet board, repair of laminate flooring, restoration of other wooden coverings. It can also be used for the manufacture of rough flooring in gazebos and auxiliary premises.
Composite material made from sawdust and glue
WPC is made by hand according to the following scheme:
- Grind sawdust in a coffee grinder or hand-held kitchen grinder until dusty.
- Add PVA glue to the crushed sawdust (proportions - 30 to 70%) and mix these components until you get a mixture with the consistency of a paste.
- Pour dye into the prepared composition (it is recommended to use additives used for ordinary water-based paint). Mix everything again.
So you have made homemade wood-plastic! Feel free to fill holes in the holes with this mixture. wooden floors. After the WPC has hardened, the restored area will only need to be sanded using fine-grain sandpaper. The composition, made with your own hands, can also be used for arranging new floors. Collect and make homemade WPC in required quantities and fill it with formwork structure. Thickness homemade boards in this case it should be at least 5 cm. Go for it!
Intended for the production of simple parts used for household needs, and elements of complex machines and mechanisms. In particular, the durable and lightweight material is used for the manufacture of yacht hulls, car and motorcycle body kits, and aircraft skins.
Fiberglass consists of a reinforcing element, fiberglass, and filler, polymer resin. Fiberglass is a collection of fibers arranged in a special way, soaked epoxy resin . Depending on the thickness, the material may have weight square meter from 300 to 900 grams.
Hand molding method
In modern industrial production are used various technologies production of fiberglass.
For creating fiberglass parts with your own hands, the most suitable method is hand molding. The work technology does not involve the use of complex equipment and expensive materials.
In order to make fiberglass with your own hands using the manual molding method, you must sequentially perform the following stages of work:
- selection of materials;
- cutting fiberglass;
- creating a separating layer in the matrix;
- creation of a covering layer;
- laying fiberglass in the matrix;
- application of a polymer composition;
- repeating the two previous steps required amount times (depending on the thickness of the product);
- drying of the product;
- removing the product from the mold;
- final processing (if necessary).
The main feature of the manual molding method is the high degree of dependence of the quality of the finished part on the level of skill of the performer. In order to get the most complete picture of making it yourself, it is necessary to consider each of the stages in detail.
Selection of materials
The type of matrix material is adopted depending on the number of serially produced parts. For one-time molding, the matrix can be made of gypsum. If it is necessary to produce more than a thousand samples, a steel matrix is ordered. At home, the matrix is often a cast with original model. It is most convenient to make a cast from fiberglass using the technology described above.
The choice of type of fiberglass depends on the requirements for strength and aesthetic characteristics finished product. A fabric with fine fibers will give the surface a smooth, glossy look, and the use of coarse fiberglass will provide high performance strength.
The composition of the polymer resin is also determined based on the purpose and operating conditions of the part. The polymer filler is responsible for such specifications fiberglass, such as:
- product color;
- degree of waterproofness;
- Operating temperature range;
- exposure to chemical reagents and environments;
- sensitivity to ultraviolet radiation;
- level of fragility, softness, impact resistance of the product.
Preparation of fiberglass
The cutting of fiberglass is carried out according to a template made of thick cardboard according to the dimensions of the matrix. If the product has complex shape, it is allowed, as an exception, to use fiberglass cutting consisting of several individual elements.
Depending on the thickness of the part, it is prepared required number of layers of material, which are stored in a convenient, easily accessible place, in the order of their formation in the matrix. If there is a break of several days between the processes of cutting glass fabric and molding products, it is necessary to strictly observe the storage conditions of the material.
Separating layer
The separating layer applied to the surface of the matrix mold serves to ensure the possibility of safe removal of the finished product after it has gained strength. The material from which the separating layer is made is often gel or car wax.
Cover layer
For laying the top and subsequent layers of fiberglass, epoxy or polyester resin. The components are mixed and infused according to the technological regulations of the manufacturer. The prepared composition must be used within 15 minutes, and therefore the resin is prepared anew for each subsequent layer.
The covering layer is the first layer laid in the matrix and, at the same time, the top protective layer products. Its thickness should be no more than 0.4 mm to avoid cracks during the drying process. The drying process of the coating layer lasts until it turns into a gelatinous sticky mass.
Laying fiberglass and impregnating with resin
After reaching the required consistency of the coating layer, the cutting of fiberglass fabric is laid into the matrix shape. The first layer of fiberglass is the thinnest (300 g/m2), which provides maximum smooth surface products.
The fiberglass fabric must exactly follow all the bends of the matrix shape without delamination and the formation of air pockets.
After laying, a layer of polymer resin is applied to the fiberglass, and the resulting shape is rolled with a special roller for better impregnation and squeezing out air bubbles. The next layer of fiberglass is laid without waiting for the resin to dry. Then the process of preparing and applying the polymer composition is repeated.
Depending on the thickness and required strength of the product, a different number of layers of fiberglass and impregnation are formed. Glass felt or thin finishing fiberglass fabric is used as the last layer.
Demolding and finishing
Removing the product from the matrix must be done after the material has gained strength in order to avoid its deformation and delamination. Under normal conditions, the drying time for fiberglass is from 12 to 24 hours. This time can be reduced by warming up the matrix infrared emitter, or by placing it in a drying chamber.
Finishing includes trimming and sanding the edges of the product.
If necessary, the product can be painted in desired color base paint. Finished materials can be glued to each other using polymer adhesives.
Rules for performing work
For getting quality fiberglass products, when carrying out work, the following must be taken into account:
- the surfaces of the matrix and containers for preparing polymer resin must be clean;
- air bubbles that could not be squeezed out with a roller must be removed by cutting with a blade;
- the tools used (rollers, brushes), as well as containers for mixing components, must be washed with acetone immediately after use to remove residual resin;
- the temperature in the working room should not be lower than 20 degrees to comply with the right technology resin polymerization process;
- polymer components may have toxic fumes, so work must be done in a well-ventilated area;
- Gloves should be used to protect hands;
- Smoking and using open flame sources is prohibited in the premises.
The video below explains well how to make fiberglass with your own hands. As an example, the author of the video makes “eyelashes” for car headlights.
