What Are Stabilisers?
Stabilisers are essential for making PVC processable and durable. They prevent the release of hydrogen chloride when PVC is heated, protect against sunlight and weathering, and ensure products can last decades in use.
When PVC is softened at 170–180 °C during extrusion or moulding, stabilisers prevent thermal decomposition. They also extend the lifetime of PVC in outdoor applications such as pipes, cables, and window profiles.
Types of Stabilisers
Calcium-based stabilisers (including Calcium-Zinc) are today the most widely used in Europe. They are employed in wires and cables, window and technical profiles (also foamed), and all types of pipes — including soil and sewer pipes, foam core pipes, pressure pipes, corrugated drainage pipes, and cable ducting — as well as their fittings.
They are also used in rigid calendered films where improved organoleptic properties are needed, for example as an alternative to tin stabilisers in transparent packaging. Increasingly, Ca/Zn stabilisers are replacing Liquid Mixed Metals in flexible indoor applications where strict air quality (VOC) requirements apply.
LMM stabilisers are widely used in flexible PVC applications such as calendered films, flooring, wall coverings, artificial leather, coated fabrics, toys, footwear, hoses, profiles, and plastisols. They are typically based on Ba, Zn, Ca, Mg or K carboxylates, often combined with co-stabilisers and antioxidants to optimise performance.
Liquid Ba/Zn and Ca/Zn systems successfully replaced cadmium-based stabilisers in semi-rigid and flexible PVC. They are valued for their balance of properties: good initial colour, long-term stability, transparency, weathering resistance, and compatibility with fillers and pigments.
In recent years, low-emission Ca/Zn solids and phenol-free liquids have been introduced, reducing odour and VOC emissions in building and construction applications.
Safety and Regulation
Lead and cadmium stabilisers have been fully phased out in Europe under the VinylPlus® commitment – cadmium by 2001, lead by 2015 – well ahead of global regulations.
Only safe alternatives are used today, all fully compliant with REACH and other strict EU frameworks.
Stabilisers typically make up just 1–5% of a PVC formulation, and they are firmly bound in the polymer matrix, meaning they do not migrate during use or recycling.
For legacy PVC waste containing lead or cadmium, dedicated EU rules ensure safe recycling and resource recovery without risks to people or the environment. The PVC industry is also developing advanced recycling technologies to manage legacy additives.
