Steady Increase of Demand for Para-Phenylenediamine Antioxidants     

Rubber antioxidants can be classified into naphthylamine, quinoline, para-phenylenediamine (PPD) and diphenylamine categories. Major varieties that have excellent properties and are suitable for the use in radial tires are PPD and quinoline antioxidants. PPD antioxidants have gained extensive applications because they have the best protective property. For many years China has regarded the increasing application proportion of PPD antioxidants and the reduced proportion of carcinogenic naphthylamine antioxidants as a focus in adjusting the industrial structure of rubber assistants.
   Major varieties of PPD antioxidants include 4010, 4010NA, 4020, 3100 and H. Antioxidant 4010 has already been discarded. Due to their poor property/price ratio, antioxidant 3100 and antioxidant H have very small output and consumption. Varieties of PPD antioxidants being used in China today are mainly 4010NA and 4020.

Constant increase of output

By the end of 2008 China's PPD antioxidant capacity was around 120 000 t/a. Major producers include Sinopec Nanjing Chemical Industry Co., Ltd., Jiangsu Sinorgchem Technology Co., Ltd., Taian Flying Chemicals Co., Ltd., Jiangsu Donglong Chemical Industry Co., Ltd. and Northeast Auxiliary Chemical Industry Co., Ltd. The combined capacity of Sinopec Nanjing Chemical Industry Co., Ltd. and Jiangsu Sinorgchem Technology Co., Ltd. accounts for around 80% of the national total.
   The output of PPD antioxidants in China has increased rapidly in recent years. Output (including only 4010NA and 4020) was around 20 000 tons in 2002 but reached around 88 000 tons in 2008 - an average annual growth of around 28%.
   Due to the rapidly increasing output of all antioxidants, China turned from a net importer of antioxidants into a net exporter in 2005. The net export amount has been basically maintained at around 5 000 tons a year in recent years. The import amount of antioxidants in China was 12 636 tons in 2008, the export amount was 18 192 tons and the net export amount reached 5 556 tons. Although the export amount is larger than the import amount, the average import price is much higher than the average export price. Exported varieties are mainly quinoline and diphenylamine antioxidants with a relatively low price. The export volume of PPD antioxidants is relatively small. Imported varieties are mainly PPD antioxidants with a relatively high price and small amounts of phenol and phosphite antioxidants.
   For PPD antioxidants, China is still a net importer today. According to incomplete statistics covering major import and export enterprises, the net volume of PPD antioxidants imported by China was around 5 000 tons in 2008. The consumption of PPD antioxidants in China was around 100 000 tons that year.
   Because of the brisk market demand, major varieties of PPD antioxidants were in short supply and the price was high from January to August 2008. With the financial crisis, the price of PPD antioxidants started a drastic reduction after September 2008. For example, the market price of antioxidant 4020 in eastern China dropped from RMB41 000-42 000 per ton in August to RMB31 500-32 000 per ton at the end of 2008. The market price of PPD antioxidants in China saw an overall decline in 2009. The market price of antioxidant 4020 in eastern China has already dropped to RMB26 500-27 000 per ton at present.

Relatively high technical level

There is only a small gap between China and leading countries in the technical level for the synthesis of PPD antioxidants. The technology for the synthesis of 4-aminodiphenylamine, a major intermediate of PPD antioxidants, has already reached a world advanced level. Most producers of PPD antioxidants and their intermediates in China use clean production processes and are no longer affected by stringent environmental protection requirements. Owing to the relatively low price of raw materials and the upgrading of synthesis technologies, PPD antioxidants produced in China are very competitive in the international market.
   With the sustained development of the tire sector, the constant increase of the proportion of radial tires in particular, the demand for high-performance PPD antioxidants in China will increase steadily. It is expected that the demand for PPD antioxidants in China will exceed 160 000 tons in 2015. The PPD antioxidant sector has bright development prospects.