China's plastic additives are in urgent need of upgrading

The reporter recently interviewed Zhang Fang, assistant to the Dean of the Petroleum and Chemical Industry Planning Institute, and learned that China has become the world's largest producer and consumer of plastic additives. However, according to European and American national standards, China currently has 80% to 90% of plastic additives. The product is unqualified and it is urgently needed to upgrade it. It is necessary to speed up the development of environmentally friendly plastic additives. The focus of development is on non-toxic plasticizers, halogen-free flame retardants and lead-free heat stabilizers.

Zhang Fang pointed out that at present, the most important plasticizer used in China is phthalate plasticizers (DOP, DEHP, DBP). Foreign countries have already banned the use of such plasticizers in plastic toys. China has also banned the use of plasticizers. Use plasticizers in plastic wraps that are used to package delicatessen and meat. In 2012, the storm of plasticizers in domestic liquors caused a shock to liquor production. The final cause was the connection of plastic pipes for liquor production equipment, which used phthalate plasticizers in manufacturing. Non-toxic plasticizers that can be replaced by non-toxic plasticizers are the preferred non-phthalate plasticizers. The most important ones are citric acid ester plasticizers. The leading products are tributyl citrate and trioctyl citrate. . The production of citric acid in China is huge, and the development of citric acid ester plasticizers has raw material advantages. In addition, the long carbon chain dinonyl phthalate and dinonyl phthalate are considered to be safer, and are also shorter carbon chain DOP, DEHP, DBP substitutes, and can pull isodecyl alcohol and 2- The development of propyl heptanol.

With respect to flame retardants, the current domestic varieties are still halogen flame retardants, including chlorine-based flame retardants and brominated flame retardants. Halogen-based flame retardants produce toxic fumes when exposed to heat, and are therefore restricted in European and American countries. Zhang Fang believes that the primary direction for the development of halogen-free flame retardants in China is inorganic flame retardants. The main varieties are nano aluminum hydroxide and nano magnesium hydroxide flame retardants. In the developed countries inorganic flame retardants account for more than half of the total amount of flame retardants. Aluminum hydroxide and magnesium hydroxide flame retardants are safe and environmentally friendly, but the compatibility of inorganic substances with organic substances is poor, and the addition of a large amount of inorganic substances tends to reduce the mechanical properties of plastic products. There are two solutions: one is the ultra-fine or even nano-scale inorganic flame retardant; the second is the surface coating of organic matter, improve the compatibility. Nano-inorganic flame retardant as the national 863 research project has been realized industrialization, with the conditions for accelerated development, China's current mandatory use of inorganic flame retardant in the cable industry, the future of inorganic flame retardant market is huge.

Organophosphorus flame retardants are low-smoke and low-toxic, and are also important substitutes for halogen-based flame retardants. China is a large country with large phosphorus resources. Phosphorus-based flame retardants have resource advantages. In 2012, the world's largest organic phosphorous flame retardant company, Albemarle Corporation, announced that it would withdraw from the production of organic phosphorus flame retardants. This is an organic phosphorus barrier in China. Fuel exports provide greater market space.

Heat stabilizers are the main auxiliaries used in the processing of PVC products to improve the thermal stability of PVC products. Traditional thermal stabilizers are lead-based thermal stabilizers. Because of the toxicity of lead, European and American countries are rapidly reducing the use of lead-based thermal stabilizers. Some European countries have stipulated that the use of lead-containing thermal stabilizers will be completely stopped by 2015. Although China does not impose mandatory deadlines for the elimination, it encourages the development of lead-free heat stabilizers and accelerates the substitution process.

Zhang Fang believes that the key development categories of lead-free heat stabilizers are rare earth heat stabilizers, organic tin heat stabilizers, and calcium-zinc composite heat stabilizers. China's enterprises have taken the lead in the global industrialization of rare earth heat stabilizers. The raw materials of rare earth elements are mainly rare earth and antimony compounds. They are safe and sanitary, and have no radioactivity. They have been used for the production of export plastic toys for many years and have enjoyed considerable popularity in the international market. China has the advantages of rare earth resources, and rare earth heat stabilizers should be the first choice for the development of lead-free thermal stabilizers in China.

Composite heat stabilizers can synthesize various heat stabilizer characteristics. Among them, calcium-zinc compound heat stabilizers are non-toxic and harmless. They are mainly used for food packaging plastic products and cling film products, but their thermal stability is not ideal. To promote it on a wider scale, it needs to be used in conjunction with other heat stabilizers. Organotin thermal stabilizers are the leading varieties in Europe and the United States. Their overall performance is good, but their prices are relatively high. China's future also has more room for development.