Plastic is used to construct poly water tanks. As the polymer oxidises, plastic objects exposed to direct or indirect sunlight may develop surface chalking. They begin to degrade, become brittle, and shatter over a period of time. The fading of colour is also accelerated by UV rays.
As a result, the sun’s ultraviolet (UV) light can harm pure polymer goods. When a polythene tank is moulded, UV stabilisers can be added to the mix, such as in the case of a polymer rainwater tank.
The use of stabiliser resin during the moulding process can inhibit or absorb the harmful UV light that causes polymer to break down. Two main stabilisers used today are:
- UV absorbers – work by absorbing the UV light, transforming it into heat and dissipating them throughout the tank. UV absorber chemistries include benzophenones, benzotriazoles and hydroxyphenyl triazines.
- Hindered Amine Light Stablisers (HALS) – do not absorb UV radiation but act to inhibit degradation. They work by targeting and neutralising free radical intermediates that are required for oxidisation to occur.
Due to interaction with the UV additive contained in the base polymer, the harmful effect of UV light is diverted away from the base polymer and colourants in both circumstances.
So, if you buy a UV-stabilized poly tank, you can be assured that it will withstand the elements in the sun. The finish of a tank can rapidly reveal whether or not it is UV stabilised; a tank with a high gloss sheen is generally UV stabilised, whereas a tank with a matte finish is not.
Finally, knowing the details of the end-use environment is critical for constructing the polymer base and processing conditions. This aids in the most efficient stabilisation. Carbon black resin, for example, can be utilised in industrial-grade tanks where the colour does not matter. This is an excellent UV absorber that may be used to store harsh compounds like sodium hypochlorite.
- UV stabilisers mean you can rest assured that your poly tank will withstand the harmful effects of the sun.
- The life of your poly water tank will last a long time – up to 20 years and more.
- Stabilisers also protect the colour of your tank from fading.
Tanks Direct’s rainwater tanks are designed and built to last in tough Australian conditions using Rotathene® SUPA UV stabilisers which exceeds the UV8 standards required by the Australian and New Zealand standard for poly water tanks (AS/NZ 4766:2006).
If you have found this article helpful, why not contact us today to discuss your needs.
For the best quality water tanks, call Tanks Direct.