How does the UV light destroy the film?
The sun's rays include many spectra, including ultraviolet rays. These radiations affect almost all materials, causing film degradation and loss of strength.
- Types of UV radiation and its effect on humans
- Kilo-Langley: how to determine the intensity of UV light?
- The effect of UV light on the film
- How to avoid the destruction of the film by UV light?
Content
The effect of sunlight on the film: what is kilo-Langley?
Types of UV radiation and its effect on humans
The sunlight plays a vital role in the life of everything that is on the planet. The composition of the rays includes various electromagnetic waves, including ultraviolet radiation. Most of it reaches the Earth and is absorbed in the Earth's atmosphere.UV (Ultraviolet) is divided into 3 groups:
- UV C – far ultraviolet. Its wavelength is in the 100-290 nanometer range. The most dangerous spectrum for people, almost all is absorbed when passing through the atmosphere.
- UV B – wavelength: 290-320 nanometers. This spectrum causes sunburn. After passing through the atmosphere, about 10% falls on the Earth's surface.
- UV A – near-ultraviolet, wavelength: 320-400 nanometers. The spectrum is poorly absorbed by the atmosphere, so radiation passes through the atmosphere.
Kilo-Langley: how to determine the intensity of UV light?
The intensity of ultraviolet radiation is variable. The level depends on the intensity of solar radiation in different geographical areas.Intensity is measured in kLy - kilo-Langley. Units express how much energy of ultraviolet radiation will fall on 1 m2 of the earth's surface during the year.
1 kLy = 1 kcal/cm2 = 41,8 MJ/m2 = 11,6 kW*h/m2
The effect of UV light on the film
Many polymer materials degrade under the influence of ultraviolet rays. The manifestations can be the following:
- discoloration,
- dimming,
- cracking,
- complete destruction of the product.
The rate of destruction depends on the time of exposure and the intensity of sunlight. This effect is called UV aging. It is one of the varieties of polymer aging. The absorption of ultraviolet light leads to the destruction of the polymer chain, which causes a loss of strength.
How to avoid the destruction of the film by UV light?
To prevent degradation, special substances are added to polymer materials. They are able to absorb ultraviolet rays. For example, in the production of long-term greenhouse films, a UV additive is used. It protects the film from rapid destruction under the influence of radiation.
Usually, manufacturers use a UV stabilizer in the production of long-term films. However, it is especially important for residents of regions with a high level of kilo-Langley to pay attention to this supplement. Without it, the greenhouse film can collapse without serving even 1 season.
NPF "Shar" uses a UV additive in all greenhouses, waterproofing, and mulching films, so our films last as long as the rules of operation are followed.
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