In modern construction, transparent materials are widely used, often completely forming the appearance of buildings. Along with the usual glass, monolithic polycarbonate properties have become widespread, and the use of which allows creating unique building structures. This plastic has excellent technical characteristics, which makes it indispensable in the construction of buildings for various purposes.
This material was first obtained at the end of the XIX century as a by-product in the process of synthesizing medicines for pain relief. A completely logical question arises: what is polycarbonate monolithic, and what properties does it have? It is an insoluble compound in water and many other liquids that can compete with high-quality silicate glass for transparency.
Monolithic polycarbonate technical characteristics, which are at the highest level, belongs to the group of thermoplastics. The most widespread aromatic compounds synthesized from bisphenol A. In turn, this substance is obtained by condensation of relatively inexpensive components of acetone and phenol. This circumstance makes possible its widespread use in construction and other fields.
Consumer polycarbonate is supplied to the consumer as a sheet material with a thickness from 1 to 12 mm of a standard size of 205 * 305 mm. By special order it is possible to manufacture panels with other geometrical parameters while maintaining the width. This limitation is due to the standard dimensions of the extruder used to make the polymer.
Industrial production of monolithic polycarbonate is carried out in accordance with TU 6-19-113-87. This provides the material with the necessary characteristics in terms of the following parameters: tensile strength, toughness and resistance to low and high temperatures. Currently, the nomenclature of polycarbonates produced in our country and abroad consists of dozens of items.
In this list, the following brands of this material, different in some properties and characteristics:
In addition to transparent monolithic polycarbonates, the industry offers the consumer panels with a low degree of light transmission in a variety of colors.
Indicators of the resistance of polymer panels to climatic conditions are determined by the relevant Russian and international standards. Monolithic polycarbonate has a significant frost resistance, it is allowed its use for the manufacture of external structures. The latter can be used at temperatures up to –50 ° C under the condition that there are no mechanical loads; at –40 ° C this material is able to withstand even shock effects.
The heat resistance of most polycarbonate grades is up to + 120 ° C for individual samples; this indicator reaches +150 ° C. Like all materials when heated, the polymer increases in size, the coefficient of thermal linear expansion is determined by a special method. For monolithic polycarbonate, its value is 6.5 * 10-5 m / ° C, which makes it possible to use it for the manufacture of especially important exterior structures. They successfully work in conditions with significant temperature differences.
Monolithic polycarbonate is a polymer that can effectively withstand destructive environmental factors. The material is inert with respect to many aggressive media, and its given ability depends on the temperature and concentration of substances.
Panels are notable for high chemical resistance with respect to the following compounds:
However, some chemical compounds are able to react with the polymer, which leads to the gradual destruction of the panels.
For the convenience of the reader, information on the resistance of polycarbonate to certain liquids is presented in the form of a table:
Acetic acid | + | Hexane | + |
Common Salt | + | Hydrogen peroxide, concentration up to 30% | + |
Butyl alcohol | + | Gasoline, diesel and mineral oils | + |
Ethanol | + | Ammonia | - |
Hydrochloric acid , up to 20% | + | Butyl acetate | - |
Propane | + | Diethyl alcohol | - |
Boric acid | + | Methyl alcohol | - |
Potassium permanganate, max. conc. 10% | + | Alkaline solutions | - |
The sign "+" in the table means the material's resistance to long-term exposure to the specified substance. |
Panels are characterized by their ability to withstand the most diverse loads for a considerable period of time. Certification of polycarbonate in terms of mechanical strength is made in accordance with the requirements of Russian, American and international standards.
The advantages of this material should include the following:
Polycarbonate sheet is highly resistant to shock. Thus, when conducting tests without preliminary incision of the material, it remained intact at maximum loads achievable in laboratory conditions. Especially durable panels are used to manufacture protective products and means to ensure the safety of citizens and law enforcement officers.
Polycarbonate monolithic, unlike glass, is able to bend under normal environmental conditions. This property of the material is widely used in the manufacture of various kinds of rounded structures: sheds, fences, and the like. This quality is characterized by a maximum bending radius, which depends on the thickness of the sheet.
Detailed information on this issue is presented in the graph:
Dependence of the maximum possible bending radius on the thickness of the monolithic polycarbonate sheet.
The industry offers an extensive range of transparent and opaque panels of a wide variety of colors. Monolithic polycarbonate characteristics, which are unique in many respects, have a density of 1200 kg / m3. This is significantly lower than window glass, which has more than twice the specific gravity. This circumstance makes it possible to greatly facilitate many building structures, provided that their mechanical strength is maintained at an appropriate level.
Knowledge of such an indicator as the weight of one square meter of monolithic polycarbonate is necessary to determine the mass of the roofing material when carrying out design work.
The mass value of monolithic polycarbonate will depend on the thickness of the sheet of material: its thickness.
Polycarbonate monolithic panels have selective light transmission. To achieve this effect, a protective coating is applied to the surface of the sheet by extrusion.The thickness of this layer is sufficient for delaying and absorbing radiation from the ultraviolet part of the spectrum, while visible and soft infrared light freely penetrates the barrier. Depending on the brand of plate, the protective coating is applied on one or both sides.
The extrusion technology used eliminates the possibility of peeling it from the substrate due to the interpenetration of materials. Another technology to protect the panel from exposure to UF radiation is the use of special additives stabilizers in the volume of plastic. This method of protecting the polymer is more expensive, but its effectiveness is much higher.
To protect the monolithic polycarbonate from damage during storage and transportation, it is glued over with plastic wrap. It indicates the brand of the panel and the side on which the protective coating is applied. The film is removed directly during installation or immediately after it, otherwise it will be difficult to remove from the surface of the panel.
Polycarbonate under the influence of an open flame and when a certain temperature is exceeded, it begins to melt and it ignites. At the termination of external influence this process spontaneously fades out. Polymer panels have the following features in terms of fire safety:
Polycarbonate monolithic belongs to the category of self-extinguishing materials. This allows it to be classified as V-1 (B1) for fire safety in accordance with the requirements of UL-94 and DIN 4102. At the same time, no flame retardants and other additives are used in the production process of the material.
Monolithic polycarbonate panels are made from pellets by extrusion or injection molding.
The life of this material is determined by the following factors:
Different manufacturers declare their terms of use of the material, and the minimum figure exceeds 10 years. Studies conducted in a specialized laboratory, showed long-term exposure (more than 2000 hours) causes a decrease in the permeability of the panel by less than 10%. This corresponds to approximately 20 years of operation of polycarbonate in the desert regions of Arizona or Israel.
As mentioned above, monolithic polycarbonate is produced from raw granules on special equipment with a closed technological cycle. This method of manufacturing panels allows you to minimize the negative impact on the environment. By itself, the material is chemically inert and does not emit any harmful and dangerous substances for humans and animals.
Monolithic polycarbonate in its environmental characteristics is recommended for indoor use. Special brands of panels are made specifically for use in medicine and the pharmaceutical industry. Allow the use of this material in construction for the execution of exterior and interior decoration.
The industry produces several types of polycarbonate with different permeability indices for sunlight and artificial lighting. For light transmission transparent panels have the following indicators from 86 to 89%. At the same time, the introduction of special additives into the material makes it possible to change the optical properties of the material and to achieve maximum absorption of the ultraviolet rays of the spectrum.
Other optical indicators of polycarbonate characterize the degree of its transparency. Thus, the yellowness index for colorless samples is no more than one unit, and the degree of turbidity does not exceed 0.5%. The panels of this polymer are in no way inferior to silicon glass, and along with other advantages, they retain their characteristics throughout the entire life cycle.
Monolithic polycarbonate does not belong to the category of materials intended to reduce energy loss through the building envelope. However, these panels have a lower thermal conductivity than ordinary window glass. For polycarbonate, this characteristic has a value of 0.2 W / mK, measurements were made according to the method approved by DIN 52612. Window glass also has a high thermal conductivity.
It should be borne in mind that the insulating properties of the material increase with increasing its thickness.So, all other things being equal, a sheet of monolithic polycarbonate at 8 mm is almost 20% more efficient than similar glass. An even greater difference is observed when installing two or more panels with an air gap between them. In recent years, this polymer is increasingly used in glass packs instead of traditional glass.
Glazed balcony with monolithic polycarbonate.
Monolithic polycarbonate has a viscous internal structure of the plate and, due to this feature, is able to effectively absorb sounds. According to the results of measurements, the level of noise insulation for slabs with a thickness of 4 to 12 mm varies within the limits with a minimum value of 18 dB and a maximum value of 23 dB.
Polycarbonate monolithic has a lower density than window glass and as a result is capable of significantly attenuating sound waves in a particularly low frequency range. This property of the material allows its use for the manufacture and installation of sound-absorbing screens along busy highways.
Monolithic polycarbonate is non-hygroscopic, in other words, the polymer does not absorb water. This property makes it possible to use it in rooms with high humidity in greenhouses, hotbeds, pools and other facilities of this kind. To prevent the formation of condensate on the inner surface of the plate during the production process, a special polymer film can be applied. Special material marks have a corresponding designation on the protective film and are coated with the coating inwards during installation.
Monolithic polycarbonate manufacturers offer their customers, in addition to transparent sheets, also painted. In different companies, the color range of plates may differ significantly from the products of competing enterprises.
The most common are the following colors of plates:
Transparent
Bronze
Black
Red
Milky
Green
The dyeing of the panel is made by introducing pigment into the mass of material immediately prior to molding. This technology provides high color uniformity and significant durability. The coloring composition is evenly distributed in the entire volume of the panel, which prevents it from burning out. Some companies, manufacturers of this material offer other color solutions for individual orders.
Transparent and painted plastic panels are becoming increasingly popular with the consumer and are increasingly becoming a substitute for silicate and quartz glass. Monolithic polycarbonate, the use of which in construction is constantly expanding, is also in demand in other industries.
The main areas of use for transparent and colored panels are as follows:
1. Production of domes in buildings and on the street.
2. Glazing of vertical surfaces in the construction of houses and public buildings.
3. Device canopies, canopies over the entrance doors and stops of the route transport.
4. Glazing of terraces and other structures of complex shape with bending panels.
5. The device domes over outdoor pools.
6. Production of sound-absorbing barriers along highways, which can significantly reduce the level of noise.
7. Production of greenhouses, greenhouses and winter gardens.
8. Installation of partitions in offices, retail, museum and exhibition halls, as well as in industrial plants.
9. Production of outdoor advertising tools and scoreboards at stadiums, train stations and other public places.
10. The device of transparent floors with lighting.
11. Fences for stairs and balconies.
12. Installation of protective barriers over the sides of hockey rinks.
In recent years, the scope of use of monolithic polycarbonate panels has been expanding. The material is also used in medical institutions for the device boxes with sterile conditions and the production of other special equipment.
This material is distinguished by simplicity and convenience in the manufacture, molding and fastening of parts. Manual or electric tools with a steel cutting surface can be used to work with monolithic polycarbonate. It is important that circular or band saws have the correct sharpening. For professional use, carbide or carbide tipped tools are recommended for cooling the cutting point or drilling with compressed air.
In the manufacture of monolithic polycarbonate structures, the following material processing methods are allowed:
Monolithic polycarbonate sheets can be cold and hot formed. In this case, the minimum allowable bending radius should be 150 times the thickness of the panel. Sheet rounding should be carried out exclusively along the extrusion line. The correct direction of bending is necessarily indicated on the protective film, which is removed during installation.
Fastening sheets to building structures can be carried out using self-tapping screws with a press washer and polymer or rubber gaskets. Separate panels are interconnected using special solvents, welding and other means. Proper installation of monolithic polycarbonate provides the possibility of its use during the entire period of operation.