Tangling Difficulties for Aqueous-Phase CPVC Makers    

By Liu Lingmei, Shanghai Chlor-Alkali Chemical Co Ltd    

As aqueous-phase chlorinated polyvinyl chloride (CPVC) has better chemical corrosion resistance and also higher heat-resistant temperature than polyvinyl chloride (PVC), it can be used in relatively stringent conditions such as pipes, profiles and cable materials.
   Many enterprises in China have developed their own aqueous-phase CPVC production technological processes in recent years, leading to a sustained expansion in the capacity and a vertical down for the price of CPVC powder. For example, the market price of aqueous-phase CPVC pure powder imported was sold at more than RMB18 000 per ton in 2009, but has dropped to around RMB15 000 per ton this year. The market price of aqueous-phase CPVC pure powder produced by Chinese local companies has only been maintained at around RMB12 000 per ton. It is expected that China's capacity of aqueous-phase CPVC will increase further around 2011. Serious oversupply may probably appear and the price will have no opportunity to rise.
   In terms of production technology, most of Chinese domestic aqueous-phase CPVC resin enterprises have not yet solved technical problems such as the quality of raw material (special PVC) and the stability and uniformity of the chlorination process. Aqueous-phase CPVC resin they produced on the basis of the present technical level still can not compete with imported products in quality. Many CPVC processing enterprises in China still favor imported resin as raw material. The further increase of demand for domestically made CPVC resin is therefore restricted to a considerable extent.
   Moreover, compared with PVC resin, the processing of aqueous-phase CPVC resin has greater complexity. To remove difficulties in its processing, the problem of CPVC resin blending must be solved first. As a matter of fact, the core technology in the research and development of aqueous-phase CPVC resin is the technology for blending CPVC, i.e. the technology for the blending of CPVC pure powder with processing assistants. It is the key technology in the manufacturing of high-quality pipes, profiles and cable materials. In spite of long-time efforts in technical research conducted by many enterprises and research institutes in China, no fundamental breakthroughs have yet been made. There is still a big gap compared with similar technologies in foreign countries. Quite a few multinationals are actively seeking ways to sell technologies for aqueous-phase CPVC pure powder production in China, but will never license technologies for CPVC resin blends here. To achieve large-scale application dissemination of aqueous-phase CPVC resin, China's local enterprises should make breakthroughs in key technologies for CPVC resin blends as quickly as they can.
   Cases of fake CPVC pipes, profiles and cable materials are rampant in China today. So-called CPVC pipes, profiles and cable materials processed from reclaimed PVC resin have been discovered in many regional markets such as Shandong, Anhui and Jiangsu provinces. Their price is very low. Not only is the reputation of CPVC pipes, profiles and cable materials seriously damaged and the interests of enterprises making normal and legal production disturbed, the application dissemination of CPVC materials in China is also affected.
   In a situation such as it is today, therefore, it is not proper and smart for Chinese enterprises to expand blindly or construct new units. They should make greater efforts in the improvement and upgrading of product quality and the expansion of market application. What is more important, they should master technologies for CPVC resin blends as soon as possible and resolutely ban the market of fake CPVC products. Only in this way can difficulties in the production and application of domestically-made aqueous-phase CPVC resin be quickly and thoroughly removed.