The Eco-friendly Path of Light Stabilizers for China's PVC Products

The Eco-friendly Path of Light Stabilizers for China's PVC Products

China's plastics industry is advancing its lead-ban work in an orderly manner, and encouraging progress has been made in products such as children's toys, UPVC water-supply pipes, electronic information products, and artificial leather. However, according to statistics from the Plastic Additives Professional Committee of the China Plastics Processing Industry Association, among the more than 500,000 tons of light stabilizers produced in 2012, lead-free products accounted for less than 20%. Lead-salt stabilizers still hold an absolutely dominant market share, and lead-free stabilizers are limited to a few varieties explicitly banned by national standards and PVC products exported to Europe and the United States. The eco-friendly path for light stabilizers in China's PVC products still has a long way to go.

   Lead, as a heavy-metal toxin, is extremely harmful to the human body. Yet it exists in many corners of daily life, building pipes being one of them. Lead-salt precipitation from plastic water-supply pipes directly causes heavy-metal contamination of drinking water. At present, Beijing and Shanghai have passed decisions to ban lead in water-supply pipes.

   The 2004 announcement of the Ministry of Construction clearly stated that UPVC water-supply pipes used nationwide must be made with non-lead-salt stabilizers. European countries such as Norway, Finland, Sweden, Denmark, and the UK had already taken actions to ban lead-salt stabilizers starting in 2000.

   Other PVC products using lead salts as stabilizers also face a comprehensive lead-ban situation. The Ministry of Electric Power has decided that all CPVC power-protection pipes within the scope of its network-access certification are prohibited from using lead salts and organotin stabilizers, in order to prevent environmental pollution as public awareness of lead-salt contamination deepens.

   There are 4,050 types of light stabilizers produced at scale domestically, and currently more than 200 enterprises produce plastic light stabilizers. Low-grade lead-salt stabilizers remain absolutely dominant: 60% of enterprises mainly produce lead-salt stabilizers, and over 80% of PVC products still use lead salts as stabilizers, with annual consumption reaching about 70,000 tons.

   Plastic light stabilizers will develop toward low-toxicity, pollution-free, composite, and high-efficiency directions as global environmental and health awareness gradually strengthens. Among them, calcium/zinc light stabilizers are a competitive product category. Some foreign calcium/zinc stabilizers perform well, and although their selling price in China is relatively high, their dosage in products is relatively low—only about 2–3 phr. At present, many domestic manufacturers already use German products.

   Domestic light stabilizer producers should accelerate product structure adjustment to meet the requirements of the lead-ban situation, and promptly develop low-toxicity, pollution-free, composite, and high-efficiency light stabilizers as substitutes for lead salts.

   Accelerating the pace of the lead-ban in the PVC products industry and advancing the eco-friendly process of light stabilizers is the general trend of China's plastics industry. Cao Jian, Executive Vice President of the China Plastics Processing Industry Association, stated that accelerating the eco-friendly process of the PVC products industry is not only a requirement imposed by the external environment on the plastics processing industry, but also an intrinsic need for the industry itself to speed up structural adjustment, strengthen innovation-driven capability, and achieve industrial upgrading and sustainable development. Plastic products are closely related to people's daily lives; ensuring the safety of plastic products is a social responsibility and obligation that the plastics industry must bear.