Durable applications with PLEXIGLAS®
There are many transparent plastics which are difficult to distinguish from one another at the time of purchase. However, their chemical composition differs considerably – and with it, so do their properties.
This becomes very apparent in exterior applications: Within just a few years, sunlight, wind and weather can cause dramatic changes to many plastics. They can no longer withstand the impact of the weather and they begin to turn yellow, become brittle and can break. But not PLEXIGLAS®!
Why plastics weather
The number of different types of plastic available today is virtually endless. However, all of them have one thing in common: They are made from molecular chains. The way in which the molecular chains are structured – how long they are, the atoms they consist of, etc. – determines the appearance, quality and mechanical properties of the plastics. Among other things, the composition determines just how stable the connections created by the molecules are. When UV light and other weather conditions impact the plastics, the molecule chains can – greatly simplified – be damaged. This results in the material properties changing. It can, for example, turn yellow, become coarse or brittle – effects which can be compared to when metals begin to rust.
On the one hand, the extent to which the plastics change under weather influences depends on the intensity thereof, for example UV radiation and moisture. This impact is affected by the geographical location, weather, place of installation, light wavelength and similar factors. On the other hand, in addition to the weather influences, the internal composition of the plastics is decisive; in other words, how stable are the molecular connections.
Comparison of weather resistance
Many plastics react relatively quickly to weather influences. The image shows seven different transparent plastics which were subjected a standardized weathering test (ISO 4892-2). Their unused condition (on the left) and their condition after 7,500 hours of artificial weathering, which, depending on the geographical location, corresponds to a real operating span of 8 to 10 years.
The test shows: The direct influence of UV radiation and moisture results in dramatic changes on most plastics. In contrast, PLEXIGLAS® remains virtually unchanged in its appearance, as the material possesses an inherent protection against weathering.
What is NATURALLY UV-STABLE technology?
PLEXIGLAS® consists entirely of extremely strong UV-stable molecules, a feature known as NATURALLY UV-STABLE technology. In this regard, it is comparable to stainless steel, the internal composition of which is also responsible for the fact that rust does not occur. Incidentally, depending on the application, PLEXIGLAS® can either protect against UV radiation or be procured in a UV-permeable variant. UV-permeability is an important property for applications in greenhouses, for example, while UV-impermeable versions are used for cockpit windows in helicopters, amongst other applications.
Comparison of permeability of PLEXIGLAS®
Thanks to the NATURALLY UV-STABLE technology, virtually all colorless, transparent solid sheets, multi-skin sheets, corrugated sheets, blocks, tubes and rods sold under the PLEXIGLAS® brand are UV-stable. This means that they do not turn yellow or become brittle and retain their high light transmission – in contrast to many other plastics which lose a great deal of their light transmission due to weathering, as illustrated by the adjacent image.
What are the benefits of UV protective layers?
UV protective layers are frequently applied to less weather-resistant plastics. Paints or other coatings are often very thin and are easily scratched, or can flake and crack, meaning they cannot always guarantee permanent protection against weather influences. PLEXIGLAS® does not need protective layers because it is UV stable through and through.
Good for a long time
Due to its durability, PLEXIGLAS® can easily remain in an application for several decades. We guarantee that virtually all colorless, transparent solid sheets, multi-skin sheets, corrugated sheets, blocks, tubes and rods sold under the PLEXIGLAS® brand will not yellow and will retain highest transparency for 30 years. We also guarantee that colored versions will remain colorfast for 10 years.
Yet how long PLEXIGLAS® is actually in use varies depending on the intended application. From just a few days when used in the construction of trade fair booths, to many years in aircraft windows, picture glazing for valuable pictures in museums or construction applications around the world. Utilization periods of up to 30 years and longer are common for exterior applications such as façades, noise barriers, industrial or private roofs, thereby contributing to delaying the renewed production of a product, thus saving resources.
It’s not a disposable product
However, the sustainability of a material depends on additional factors including what happens with the material once it reaches the end of its service life. As is the case with metals and glass, plastics must be disposed of properly to ensure that they have virtually no negative impact on the environment. This applies equally to single-use items, such as packaging, as it does to durable consumer goods, for which PLEXIGLAS® is generally used. PLEXIGLAS® is not hazardous or special waste and can therefore, in a positive sense, be recycled within the circular economy.
Read more in the article “PLEXIGLAS®: A recyclable material even after use.” The article also contains information regarding the share of this material in the entire volume of plastic and how the circular economy assists in taking advantage of the benefits offered by plastics and preventing negative impacts on the environment.