Polymeric materials are susceptible to oxidative degradation by the action of heat. Thermal degradation can occur during melt processing of the polymer, or during the service life of the finished component. This degradation can result in a reduction in aesthetics, physical and mechanical properties or even discolouration of the part.
Antioxidant additives interfere with the oxidative cycle, thereby inhibiting the oxidative degradation process. Antioxidants can be used effectively to:
- Improve the processing of polymers.
- Increase the service life of polymeric components.
- Give better control when incorporating recycled materials where the feed stock will has been through multiple heat cycles.
Antioxidants are traditionally split into two types; primary and secondary. Primary antioxidants are designed to give protection to the finished product, whereas secondary antioxidants are used to stabilise the polymer during processing. Antioxidant masterbatches can be supplied in pure primary or secondary form, or as blends.
Antioxidants are used widely in many polymer conversion processes. Examples include:
- Gel and black speck reduction in blown and cast film extrusion.
- Process stabilisation in fibre extrusion.
- Improving the service life of profile extruded, and injection moulded products, e.g. pipes and fittings.
- Prevention of discolouration during service and sterilisation processes.
Wells Plastics antioxidant masterbatches can be custom formulated to suit specific applications or polymer types. Please contact your Wells Plastics representative for further details.
Nonwovens and Fibre
Polymer Carriers Available