Plastics materials can be susceptible to damage by the action of UV radiation. Sunlight is a powerful source of UV radiation and products such as garden furniture, heating oil tanks, and greenhouse films which are required to spend extended periods outdoors as part of their service life will need protecting against this harmful degradation.
The use of UV stabiliser systems allows parts for prolonged outdoor use, and in different climates with differing levels of UV light exposure, to be designed with a high level of confidence that they adequately fulfil their service life and performance requirements.
Another feature of UV radiation is that it is not only potentially damaging to the polymer but also in packaging applications, to the contents of the packaging. UV radiation not only come from the sun, but can also come from artificial sources, like fluorescent lighting in supermarkets. This could potentially cause undesirable changes to packaged goods e.g. colour change, and odour and flavour loss in foodstuffs. Adding a UV absorber will help protect the pack contents from damage by UV light.
Wells Plastics have created a range of UV stabilisers, to protect polymeric materials, and UV absorbers to protect packaged materials from UV light degradation.
A common class of UV stabilisers are the hindered amine light stabiliser (HALS) systems. These work by interrupting the photo-degradation process before it can get destructively underway, thus protecting the polymer and extending the service life of the part. The mechanisms by which they achieve this used include “free radical scavenging” and “peroxide decomposition”.
Wells Plastics UV stabilisers are used in wide ranging areas including:
- Blow moulding – Water butts, Tanks, Planters, Tubs
- Injection Moulding – Garden furniture.
- Film and profile – greenhouses, pallet covers, pipes
- Fibres – nonwovens, artificial grass
Wells Plastics UV absorber masterbatches contain an active ingredient system which ‘absorbs’ UV radiation. Due to the presence of double bonds within its molecular structure, it is able to absorb light energy in the UV region and re-emit the energy in the IR region. This system prevents UV radiation from passing through the packaging material and reaching the contents inside.
UV absorbers are used in many packaging applications:
- Packaging films – pallet covers, shrink films
- Injection moulded (PP, PS and PET) pots, tubs and lids.
- Blow moulded HDPE bottles, jars and drums.
- Thermoformed , PP and PET trays
Wells Plastics UV stabiliser and absorber masterbatches can be custom formulated to suit specific applications or polymer types. Combination masterbatches containing both a stabiliser and an absorber are available. Please contact your Wells Plastics representative for further details.
Nonwovens and Fibre
Polymer Carriers Available