CSM Opportunities Can Be Expanded in China

By Qi Shujing, PetroChina Jilin Petrochemical Co., Ltd. Research Institute

Chlorosulfonated polyethylene (CSM) is a special rubber produced through the chlorination and chlorosulfonation of LDPE or HDPE. It has a uniquely wide range of excellent properties such as oil resistance, heat resistance, weather resistance, ozone resistance, corrosion resistance, flame retardancy, toughness and abrasion resistance. Moreover, it can be compounded to retain permanent bright colors. CSM has gained extensive applications beyond the mainstream of the rubber sector in waterproofing materials, coatings, automobile components and electrical wires/cables, and it has become a commonly-used specialty rubber.

1. Modest demand growth

The consumption of CSM in China was around 3 600 tons in 2012. Fifty five percent of the CSM40 produced in China is used to manufacture rubber hoses, 40% is used to manufacture electric wires/cables and 5% is used in other rubber products. Seventy percent of CSM30 is used to produce anticorrosive coatings and paints, and 30% is used to produce adhesives. CSM45 has no consumption markets in China as yet, and is made here only for export. CSM48 is only used to produce electric wires/cables. The application of CSM in the automotive sector has already started developing in recent years. In the automotive sector, CSM is mainly used in rubber hoses for air-conditioning systems, fluid transmission systems, exhaust control systems, fuel pipelines and vacuum regulation systems and also used for spark plug caps, ignition leads, sealing strips and steering wheel primers. It is expected that with the accelerated localization of automobile components and parts, CSM will remain in demand in China’s automobile sector in next few years. The consumption of CSM in China will reach 4 500 tons in 2017. Table 1 shows the consumption of CSM in China during 2008-2012. Figure shows the consumption structure of CSM in China in 2012.
   The growth of CSM sales has suffered impacts from other special rubber varieties with even more excellent properties in recent years, and CSM is being displaced in some markets by similar products such as chlorinated polyethylene and high chlorinated polyethylene. Nevertheless, the apparent consumption of CSM in China continues to increase slowly and steadily. It is expected that CSM will remain in demand in China for the next few years.

2. Product series yet to be filled out

CSM production technologies used in China today were all developed domestically. Raw materials, catalysts and stabilizers used are all basically the same as in foreign countries. Compared with foreign countries, however, China has many problems in production process technologies such as low automation level, undesirable equipment performance, unstable product quality (uneven color in appearance, high content of volatile matter and lots of mechanical impurities) and poor environmental protection. The carbon tetrachloride solvent used, in particular, damages the atmospheric ozone layer. The development level of such production processes is therefore a constraint, and it is imperative to develop new synthesis technologies and substitutes for solvent carbon tetrachloride.
   In terms of product variety, the brands produced in China have incomplete ranges of products, and there are too few varieties with a high property/price ratio like that of high chlorinated CSM. Serialized and specialized products are still in the future. In other countries, however, many varieties of CSM are used in electric wires/cables alone, such as H-40S, H-4085 and TS-530.
   CSM is now being replaced by other materials for some applications. In the waterproofing material sector for instance, EPDM, with a service life of 50 years, and PVC waterproofing material, with a lower price, are two major substitutes. In the electric wire/cable sector, chlorinated polyethylene with a low price is the top alternative to CSM. Using chlorinated polyethylene in automotive rubber hoses is more competitive than CSM. The major alternative to CSM in the adhesives sector is chloroprene rubber, which has an excellent property/price ratio.
   Considerable R&D advances have been made in finding substitutes for solution-process solvent carbon tetrachloride in recent years. Commercialization of the findings has been slow, but a sound foundation has been laid. Commercial production units using the new two-step vapor/solid-phase CSM production process have been constructed, and green production has already been achieved.
   Many advanced countries have strengthened R&D for CSM substitutes, but no new materials that can fully replace CSM have yet been discovered. CSM will therefore retain some development potential for a considerable period of time in future. The potential demand growth in China, in particular, is still quite big.

3. Caution toward investment

(a) New units must use new process technologies with environment-friendly solvents (not carbon tetrachloride) so as to meet the requirements for environmental protection.
(b) R&D for new environment-friendly solvents (alternatives to carbon tetrachloride) should be strengthened and the pace of their commercial production should be quickened. At the same time, the development and improvement of solid-phase CSM synthesis technology with low environmental impact and low energy consumption should be highlighted and developments in the R&D for aqueous-phase CSM synthesis technology should also be closely followed.
(c) To optimize the operation of existing units, greater efforts should be made in brainstorming and technical renovation for improving product quality, increasing product variety, optimizing process parameters and reducing production cost. Serialized, specialized, refined and highly purified products should be developed to reap maximum economic benefits.
(d) CSM should have a greater market space. The application sectors should be expanded constantly, and new products with property/price advantages should be sought. The production of special materials with high added value is a development orientation in the CSM sector. As is the case with other polymers, modification and blending are key methods used in the development of new CSM varieties.   

Table 1 Consumption of CSM in China, 2008-2012 (ton)
Year    Capacity    Output    Import    Export    Consumption
2008    3000    1500    1600    100    3000
2009    5000    1500    1600    -    3100
2010    6500    1500    2300    500    3300
2011    6500    3000    1100    600    6500
2012    6500    3500    200    100    3600