One of the most popular modern building materials can be called polycarbonate. How he earned his popularity, we will try to tell in this article, which describes its characteristics and use cases, recommendations on how to determine high-quality polycarbonate suitable for further operating conditions.

What is polycarbonate for greenhouses?

This is a thermoplastic polymer, or, in other words, polymer plastic, which has the form of granules and remains in this form until processing.

It and molding are produced in several ways:

• injection molding - for the manufacture of products;
• blow molding - to create volumetric vessels;
• extrusion - for profile and film;
• molding of fibers from the melt.

The composition of the substance includes:

• carbonic acid;
• dihydric phenol;
• water;
• dyes;
• solvents.

Polycarbonate is created on the basis of bisphenol A as a result of synthesis by condensation of phenol and acetone. In its pure form, the product is transparent, colorless or yellowish, but dyes are often used in production to produce colored products. For convenience, the term "polycarbonate" is often abbreviated to the abbreviation PC, or in the English version - PC. Cellular polycarbonate is successfully used for glazing:

• greenhouses;
• verandas, arbors, loggias;
• pools;
• roofing sports facilities.

This choice of material contributes to energy savings and reduces the cost of heating greenhouses.

In addition, it is used for the manufacture of:

• stops and awnings;
• acoustic screens;
• shockproof doors and windows.

Polycarbonate Properties for Greenhouses

This synthetic material has the following characteristics:

• high light transmission;
• transparency ~ 90%;
• good thermal insulation;
• good gas permeability and vapor permeability;
• light weight - the density of the material is 1.2 g / cm³;
• good flexibility, can be used for arched structures;
• low cost;
• Duration of operation - more than 10 years without loss of properties;
• fire resistant, has the property of self-extinguishing;
• durable, not inferior to aluminum, at the same time, a reinforced, multi-layer monolithic appearance can protect against a shot from a firearm;
• it is an eco-friendly material - it is safe, non-toxic, complies with FDA and EC requirements, and may come into contact with food;
• does not lose its properties at high temperatures, up to + 60 ° C, and at significant temperature fluctuations;
• holds ultraviolet rays thanks to a special protective agent included in its composition;
• does not require protection against mechanical damage.

Polycarbonate becomes brittle only at very low temperature values ​​- below –50 ° C, which are not encountered during operation.

Important! When exposed to high temperature, the material can expand up to 4 mm, which is important to consider when creating a project and using it in construction.

You should know that this type of plastic is not resistant to the action of such chemicals:

• ethanol;
• petrol;
• ammonia;
• kerosene;
• solvents and varnishes.

With their prolonged aggressive action, it can partially soften, dissolve or absorb the substance. Cracks may appear, especially if the PC is in a stressed or deformed state. Based on this, it is worth remembering that care for polycarbonate should be carried out by means that do not contain the above components.

Types of polycarbonate for greenhouses

Next, it is worth considering the question of what polycarbonate is used for the manufacture of greenhouses:

• monolithic;
• profiled;
• cell phone.

The main difference between these types is the structure of the material:

• monolithic - continuous, smooth, transparent sheet;
• cellular - with partitions between hollow cells;
• profile - corrugated, wavy, corrugated structure.

PC release form, as a rule, is a sheet of standard sizes. For the construction of greenhouses, cellular polycarbonate is most often used, since empty honeycombs help maintain precious heat inside the greenhouse, while internal partitions make the structure more rigid and durable.

Monolithic polycarbonate

It is recommended to use this type of polycarbonate instead of silicate glass, since this material has the following advantages:

• high impact resistance - 20–21 kg / m²;
• good ultraviolet absorption;
• flexibility;
• transparency;
• safety during a fire;
• durability of use - the service life can reach 15 years, with a 10-year manufacturer’s warranty.

This is the best transparent, and at the same time durable material that exists on the modern building materials market. It is 250 times more durable than ordinary glass.A monolithic PC has a coating with a sun-protection function on both sides, which is an advantage compared to cellular polycarbonate, since it allows more economical use of the material during installation.

Profiled Polycarbonate

In fact, this type of polycarbonate is identical to monolithic, but it has a modified shape in the form of a corrugation or wave. As a rule, its thickness is 7-14 mm. A profiled PC is used to replace metal corrugated board.

This type of material has the following characteristics:

• high strength;
• good light transmission due to transparency;
• resistance to weather changes, including temperature fluctuations and the effects of the elements in the form of a hurricane, snowfall, etc .;
• flexible;
• easy;
• wear resistant;
• reflects ultraviolet light;
• presented in a wide range of colors;
• when mounting structures there are no difficulties;

A distinctive feature of a profiled PC from other forms is:

• increased strength due to the presence of stiffeners - withstands up to 300 kg / m² of snow cover on the roof of the greenhouse;
• attractive appearance due to the color scheme and structure of the material;
• resistance to condensation.

Profiled polycarbonate is obtained by forcing a plastic that is viscous in consistency through a forming hole, giving the profile a wave shape.

This type of PC can be:

A profiled profile may take the form:

• waves - then the PC is called plastic slate;
• trapezoidal - similar in appearance to corrugated board;
• U-shaped - also similar to corrugated board, but has reinforced stiffening ribs.

Cellular Polycarbonate

A distinctive characteristic of this type of PC is its shape: 2 parallel thin plates are interconnected by thin jumpers that act as stiffening ribs - this way hollow honeycombs or cells are obtained between the plastic sheets. A high-quality cellular PC has very strong stiffening ribs and weighs heavier than the cheaper and lighter options.

Did you know? Polycarbonate is used in optics for the manufacture of glasses, since it almost 200 times other than glass, and at the same time perfectly transmits light.

Cellular polycarbonate is made by extrusion, melting plastic granules and giving the mass the necessary structure. The thickness of the sheet can be even 0.3 mm, despite the fact that it will have high strength and flexibility.

Transparent Cell PC Features:

• can pass up to 92% of sunshine - due to which it enjoys increased popularity in the construction of greenhouses;
• not prone to ignition, does not emit toxic substances when burned;
• easy;
• bends well, takes the necessary shape, is easily mounted;
• good shock resistance;
• has protection against ultraviolet radiation;
• It tolerates temperature fluctuations and any weather conditions.

In addition, it is considered the best thermal insulation, in comparison with monolithic and profiled sheets, due to the air gap in the combs. 4 or 6 mm thick profiles retain 2–3 times more heat than silicate glass, optimizing energy consumption by 30–40%, therefore they are used to construct greenhouses;

Polycarbonate Selection Options

The choice of the manufacturer and the parameters of polycarbonate are primarily determined by the scope of its use.

In order to choose the right PC, you need to pay attention to such characteristics:

• density;
• thickness;
• profile weight;
• profile color;
• bending radius;
• the presence of UV protection;
• percent light transmission.

It is necessary to inspect the plastic sheets: they must be even, and also have a film with a protective UV coating on one side of the sheet. They should not have any deformations in the form of waves and bends.It is also worth noting that such a parameter as the thickness of the profile is selected based on the scope of its further application:

• 4 mm - awnings and small greenhouses, shop windows and billboards;
• 6 mm - small-area greenhouses, stained-glass windows, peaks;
• 8 mm - large greenhouses, roofing, partitions;
• 10 mm - front glazing, processing of large vertical areas;
• 16 mm - on the roof over large spans, due to high rigidity it can be used in greenhouse complexes;
• 20 mm - glazing of swimming pools, conservatories, greenhouses.

The optimum thickness for a medium-sized greenhouse is 6 mm thick, especially in regions with moderate snow activity. If the greenhouse is planned as a room for growing early vegetables, then you can use a 4-mm profile.

Density

This parameter is very important when choosing polycarbonate, since the physical qualities of the material depend on it:

• strength;
• the ability to withstand weather conditions and temperature extremes;
• profile weight.

A change in density, following the laws of physics, entails an increase or decrease in the weight of the profile, which, in turn, affects the price of the building material. So, a product with a low density can be cheaper, but it will be inferior in quality to a more expensive option, provided that profiles of the same dimensions are compared. With increasing density, the strength of the material grows, its ability to withstand more significant loads.Monolithic sheets have an average of 1.81–1.2 g / m³, honeycomb sheets of 0.52–0.82 g / m³, since the thickness of the stiffeners in honeycomb polycarbonate determines the density of the material. For the construction of greenhouses, the recommended density is 0.72 g / m³ with a thickness of 4 mm, however, if it is a seasonal structure that will not be exposed to natural elements, for example, snow pressure, then you can take a softer material, which means cheaper .

Weight

The mass of polycarbonate, like any other building material, is very important both during the creation of the project, when the load on the foundation and the total mass of the building are calculated, and at the installation stage. The undoubted advantage of PC, in relation to other materials, is its low weight, so polycarbonate is used to make structures easier, even taking into account the maximum density of the material.

The weight of the sheet profile affects its life. The weight parameter is more important when choosing cellular polycarbonate, since its weight is affected by the thickness of the interchannel partitions, which is difficult to visually assess. For a cellular PC of different thicknesses, such weight measures per 1 m² sheet were taken:

• 4 mm has an average weight of 800 g;
• 6 mm - 1.3 kg;
• 8 mm - 1.5 kg;
• 10 mm - 1.7 kg;
• 16 mm - 2.7 kg.

The weight of the sheet determines its rigidity and strength, which means that it can provide the force of impact of a strong wind, hail, and the load from snowfall. Lighter materials cannot provide good load bearing capacity. Accordingly, heavier and stronger sheets can not be cheap, and this should be taken into account when choosing offers in the building materials market and comparing profiles with similar dimensions.

UV protection

Carbon profiles require protection from ultraviolet radiation, since under its prolonged exposure they can become more cloudy and deteriorate. For this, the thinnest protective film is applied to the surface of a polycarbonate sheet by coextrusion, in other words, by spraying.

Important! During the installation of the structure, it is necessary to carefully control the way the sheets are placed - it is necessary to mount so that the side with the UV protective film is outside.

This protection makes the cost of plastic a little higher, but ensures its longer operation, while maintaining transparency. The thickness of the protective layer is tens of microns, so the protective coating is not so easy to see with the naked eye. In order not to confuse the sides of the sheets, you must:

• leave an identification mark on the side of the sheet from which the packaging with the corresponding marking was removed before installation;
• illuminate the blue light of the UV banknote detector.

Some unscrupulous manufacturers may say that substances that protect against the negative effects of sunlight were added to the plastic mass during its formation, but this is not true and will not provide any protection. As a result, such sheets can last only 2-3 years and soon lose their strength and lose transparency, becoming yellow and cloudy.

Bending radius

Polycarbonate profiles have a very valuable quality - they can bend without heating, without losing their other properties, while remaining as durable.

In order to find out how much you can bend the sheet for mounting the structure, you need to use a formula that will help to establish the maximum bending radius:

R = t × 175,

where R is the bending radius, t is the sheet thickness.

Based on this, it follows that a sheet with a thickness of 10 mm can be bent up to 1750 mm. Depending on the shape of the material, the bending radius is within 0.6–2.8 m. During installation, remember this parameter, since excessive bending can damage the UV protective coating and deform the profile structure.

Color and light transmission

Polycarbonate can provide a high level of light transmission - indicators of different types and manufacturers reach the level of 86–92%. In addition, the plastic structure provides for the diffusion of sunlight, which is another advantage compared to traditional glazing of greenhouse premises.

Thanks to the diffuse lighting, the farmed crop receives more solar energy, which comes to it from almost all sides. In order to determine what color PC is needed for building a greenhouse, you need to know that the color of the material determines its ability to transmit light.

Did you know? Red and orange light spectra, as well as blue-violet, give more strength to the plant and contribute to its growth. And in a greenhouse made of green PC, plant photosynthesis slows down, which will have a depressing effect on them.

Polycarbonate is divided into groups according to the following characteristics:

• transparent - colorless, transmits almost 86–92% of sunlight;
• conditionally transparent - red, orange, yellow, green, blue, turquoise and bronze, 35–75% of sunlight;
• opaque - silver, gold, pearl, white, milky, polyclyde, polysheid, primalite, about 20-30%.

Since it is important to ensure the maximum amount of light in the greenhouse, transparent polycarbonate is the most relevant. The Greenhouse Nano trademark has created an innovative material that contributes to an increase in yield in greenhouse conditions up to 48%.This is due to the addition of special structural nano-additives that convert the sun's rays into a 660 nm emission spectrum that promotes plant growth, which corresponds to the peak of photosynthesis.

Thus, crop ripening is faster by 3-4 weeks. The additive converts the incoming rays into the red spectrum, due to which plant photoreceptors are stimulated and the process of more intensive growth and fruiting is started.

Which polycarbonate is better for a greenhouse - cellular or monolithic?

To create the optimum temperature and maintain the necessary humidity in the greenhouse, polycarbonate profiles are ideal. However, the question may arise, what kind of PC is most suitable for creating a greenhouse.

To answer it, you should consider the parameters that determine the differences between these material options:

1. With the same sheet thickness, a cellular PC has less weight, which is necessary to create frameless structures and cover large areas.
2. The honeycomb version is more energy efficient, it retains more heat due to the layer of air between the sheets.
3. The price of a cellular profile is lower than a monolithic one.
4. The cellular profile allows you to get more diffused light, which has a positive effect on the development of plants and their productivity.

Based on this, experts recommend the use of cellular polycarbonate for the construction of greenhouses.

Greenhouse Polycarbonate Care Tips

Caring for the polycarbonate from which the greenhouse is built does not require large financial or time costs, however, you should know some rules. In the summer, if shading is necessary at very high temperatures, even with doors and ventilation openings, you can use a chalk solution that sprinkles the greenhouse. You can wash the chalk off the surface with plain water from a hose so as not to damage the polycarbonate coating. In the autumn, after harvesting and in preparation for winter, the greenhouse must be carefully cleaned.

Important! For cleaning polycarbonate, it is permissible to use chemical and disinfectants recommended by the manufacturer. This will ensure reliability and durability.

Cleaning should include mandatory disinfection. In order not to damage the polycarbonate, it is recommended to arm yourself with a soft sponge or cloth and dishwashing detergent or warm soapy water. You should also carefully monitor the processing of cracks between sheets and structural elements - sprayers and brushes are used to clean them. In winter, polycarbonate does not require special care, especially if the greenhouse is not used at this time. It is only necessary to control:

• the presence of strong contaminants that can hold snow for a long time;
• remove snow layer more than 10 cm thick from the roof surface;
• to prevent glaciation and the formation of a snow crust - for this, as snow falls or when a thaw sets in, it must be swept away with a broom if the roof of the greenhouse is not arched and the snow cap has not come off.

If the greenhouse is in the country and it is difficult to care for it in the winter, then it is recommended to disassemble the structure before the arrival of spring. With the advent of spring, the surface of the greenhouse needs to be washed from the dirt that has accumulated over the winter in order to restore transparency. If the material does not transmit light due to pollution, then it heats up more and is subject to greater deformation.

General rules:

• it is necessary to clean the surface of the greenhouse both from the inside and from the outside;
• the greenhouse should be cleaned after harvesting each crop and before each new planting.

Precautions in the process of caring for polycarbonate greenhouses:

• Do not use scrapers and abrasive detergents to clean;
• Do not remove snow with sharp and hard objects; otherwise, you may damage the surface and UV protective film;
• do not clean and wash polycarbonate when it is very hot in the sun;
• It is not recommended to allow interaction with fats and acids.

Rating of manufacturers of cellular polycarbonate for greenhouses

At the moment, the building materials market may please a large number of manufacturers of high-quality polycarbonate.

The leading positions are occupied by manufacturers whose names are listed in random order:

1. Safplast innovative - launches Novattro products.
2. Bayer material science (Covestro) is a German trademark of Makrolon.
3. Polygal plastics - Russian-Israeli manufacturer of cellular polycarbonate Polygal.
4. Plastilux trademark Sunnex - affordable quality materials made in China.
5. Polynex - A popular manufacturer of cellular PCs for greenhouses.
6. Kronos - resistant to impact and mechanical damage polycarbonate.
7. General electric plastics - Arabian manufacturer.

Profile features and properties may vary by manufacturer. Polycarbonate is a unique building material that combines the transparency of glass, the strength of metal and the lightness of plexiglass. In addition, its heat-insulating and fireproof characteristics make it indispensable in the design and construction of modern structures.