Styrene-based thermoplastic elastomer (also called styrene-based block copolymer (SBCs)) is the most abundant thermoplastic elastomer in the world, which has the most similar characteristics to rubber. At present, there are four types of SBCs series, namely: styrene-butadiene-styrene block copolymer (SBS); Styrene-isoprene-styrene block copolymer (SIS); Styrene-ethylene-butene-styrene block copolymer (SEBS); Styrene-ethylene-propylene-styrene block copolymer. SEBS and SEPS are hydrogenated polymers of SBS and SIS respectively.
SBS styrene thermoplastic elastomer is a kind of SBCs with the largest output (accounting for more than 70%), the lowest cost and the widest application. It is a triblock polymer with styrene and butadiene as monomers, which has the characteristics of plastic and rubber, so it is called "the third generation synthetic rubber". Similar to SBR, SBS can contact with water, weak acid and alkali. , with excellent tensile strength, large surface friction coefficient, good low temperature performance, excellent electrical properties and good processability, has become the most widely used thermoplastic elastomer at present.
SBS has incomparable advantages over thermosetting rubber in processing and application:
(1) can be processed and molded by thermoplastic processing equipment, such as extrusion, injection and blow molding. The molding speed is faster than the traditional vulcanized rubber process;
(2) vulcanization is not needed, so that the vulcanization process in general thermosetting rubber processing can be omitted, the equipment investment is low, the production energy consumption is low, the process is simple, the processing period is short, the production efficiency is high, and the processing cost is low;
(3) The leftover materials can be recycled for many times, which saves resources and is beneficial to environmental protection.
At present, SBS is mainly used in rubber products, resin modifiers, adhesives and asphalt modifiers. In terms of rubber products, SBS molded products are mainly used in shoemaking (sole) industry, and extruded products are mainly used in rubber hoses and adhesive tapes; As a resin modifier, a small amount of SBS mixed with polypropylene (PP), polyethylene (PE) and polystyrene (PS) can obviously improve the low temperature performance and impact strength of products; As an adhesive, SBS has the characteristics of high solid content, quick drying and low temperature resistance. As a modifier of building asphalt and road asphalt, SBS can obviously improve the weather resistance and load resistance of asphalt.
At present, China's SBS production capacity is 265,438+100,000 tons/year, while the domestic market demand has exceeded 350,000 tons. The domestic market gap is large, and the products have good market development prospects.
2 Current situation and forecast of domestic and international market demand
2. 1 foreign market analysis
The industrialized production of SBS products in the world began in the 1960s. 1963, Philips Oil Company of the United States produced the linear SBS*** polymer with the trade name Solprene for the first time by coupling method. 1965 Shell Company of the United States developed similar products with negative ion polymerization technology and three-step sequential feeding method and realized industrial production. 1967 Hualan Philips Company developed star-shaped (or radial) SBS products, 1972 Shell Company of the United States developed SBS hydrogenation products (SEBS). 1973 Philips launched star SBS products. 1980, Firestone Company launched SBS product with the trade name Streon. The styrene content of this product is 43%, and the product has a high melt index, which is mainly used for plastic modification and hot melt adhesive. Subsequently, Asahi Kasei Company of Japan, Anic Company of Italy and Petrochim Company of Belgium also developed SBS products.
Since 1990s, with the continuous expansion of SBS application field, SBS production has developed rapidly worldwide, and petrochemical enterprises in many countries have successively built SBS production devices. Especially during the period of 1994- 1995, the SBS production facility of Shell Company in Ohio, USA exploded, resulting in the shortage of SBS supply in the world market, which led to the rapid growth of SBS production capacity in the world, especially in East and Southeast Asia, such as Taiwan Province Province in China and South Korea. In addition, with the continuous expansion of the application field of styrene block * * * polymer thermoplastic elastomer in recent years, the growth of market demand is accelerated, which in turn promotes the rapid growth of production equipment capacity. During 1992-2002, the average annual growth rate of world SBS production capacity reached 8.04%, and the world SBS production capacity increased from 600,000 tons/year in 1992 to130,000 tons/year in 2002.
At present, about 12 countries and regions in the world produce SBS products, such as the United States, Italy, China, Taiwan Province Province of China, Belgium, France, Germany, Japan and South Korea.
From 1995 to 2002, the average annual growth rate of SBS consumption in the world was about 6.6%. By 2002, it increased from 567,000 tons of 1992 to 890,000 tons, which was significantly higher than other synthetic rubber varieties.
SBS is mainly used in shoemaking, adhesives, asphalt modification and polymer modification in the world. In different countries and regions, the proportion of each application field is different. In North America and Western Europe, the largest application field of SBS is asphalt modification, followed by adhesives and footwear; Japanese SBS is mainly used for polymer modification and adhesive, followed by asphalt modification; In China and Southeast Asia, the biggest consumption area of SBS is footwear.
It is estimated that the average annual growth rate of SBS product consumption in the world is about 5-6% from 2002 to 2007, and the consumption will reach115-1200,000 tons by 2007. The consumption growth of developed countries such as the United States, Western Europe and Japan has slowed down, and the Asia-Pacific region will become the center of SBS's new round of development.
2.2 domestic market analysis
China began to research and develop SBS in the mid-1970s. Beijing Yanshan Petrochemical Company Research Institute, Lanzhou Petrochemical Company Research Institute, Beijing Chemical Industry Research Institute, Shoemaking Research Institute of Ministry of Light Industry and other units have done a lot of work in SBS product research and development. 1In April 1984, Yanshan Petrochemical Company 1000-ton SBS pilot production technology was successful, and then a set of 10,000-ton industrial technology was developed.
1989, the synthetic rubber factory of Baling Petrochemical Company, Yueyang, Hunan adopted the technology of Yanshan Petrochemical Company, built the first domestic SBS production device with 1 10,000 tons/year, and put it into operation in 1990, ending the situation that SBS products in China were completely dependent on imports for a long time. 1At the end of 1996, Yueyang Petrochemical Complex expanded its SBS plant capacity to 30,000 tons/year, and198 expanded its SBS plant capacity to 50,000 tons/year. In recent years, with the rapid expansion of domestic SBS market, the capacity of 200 1 year plant has been expanded to 654.38+10,000 tons/year again.
Following Baling Petrochemical Company in Yueyang, Hunan, the Synthetic Rubber Factory of Beijing Yanshan Petrochemical Company also adopted the technology of Yanshan Petrochemical Company Research Institute in 1993, and built a set of SBS production equipment with an annual output of 10000 tons/year. Subsequently, in 1998, the production capacity of the production unit was expanded from 1 10,000 tons/year to 30,000 tons/year, and the unit basically produced pure rubber. 200 1, the company expanded and rebuilt again, and built three new SBS production lines with a total design capacity of about 60,000 tons/year, which can produce oil-filled rubber.
1997 At the beginning of this year, the 300,000-ton/year ethylene synthetic rubber plant of Maoming Petrochemical Company was put into operation. The designed annual output of the plant is 50,000 tons, namely 1 10,000 tons/year SBS, 1 10,000 tons/year low cis, and 30,000 tons/year solution polymerized styrene butadiene. Its SBS products are basically oil-filled products. 200 1 Company reformed the imported equipment, and both production lines were changed to produce SBS. The designed production capacity is about 50,000 tons/year, and the equipment is developed to produce SBS pure rubber.
Accordingly, up to now, there are three SBS production enterprises in China with a total production capacity of 265,438+0,000 tons/year. Among them, the SBS production plant of synthetic rubber plant of Baling Petrochemical Company in Yueyang, Hunan Province with an annual output of 654.38+10,000 tons/year is the largest SBS production plant in China at present, with 20 product brands; The production capacity of Beijing Yanshan Petrochemical Company is 60,000 tons/year, and the product number is11; Maoming Petrochemical Ethylene Industry Company has a production capacity of 50,000 tons/year, and the product number is 13.
In addition, the SBS production technology successfully developed by Yanshan Petrochemical Company Research Institute has not only been successful in two domestic industrial plants, but also provided complete sets of technology transfer for 10,000-ton SBS production plants of Italian Enichem Elastomer Company and China Taiwan Province Synthetic Rubber Co., Ltd.
In 2003, the output of SBS in China was 654.38+860,000 tons, the import volume was about 654.38+680,000 tons, and the apparent consumption was 354,000 tons.
Since 1995, China's SBS output has increased at a high speed of 30%, but it still can't meet the rapid growth demand of the domestic market, and the import volume has increased year by year. SBS imported from China mainly comes from Taiwan Province Province, with a small amount from South Korea and Japan.
In 2003, the total consumption of SBS in China was about 350,000 tons, of which the material for shoes was about 210.3 million tons, accounting for 60.9% of the total consumption. The dosage of asphalt modifier is about 63,700 tons, accounting for18.2%; 43,700 tons of adhesive, accounting for12.5% of the total consumption; Polymer modification16500t, accounting for 4.7%; Other 1.3 1 10,000 tons, accounting for 3.7%.
According to various consumption fields, it is briefly described as follows:
Shoemaking industry
The sole made of SBS instead of vulcanized rubber and PVC has the advantages of good elasticity (little stress or residual deformation), beautiful color, good wet skid, air permeability, wear resistance, low temperature resistance and bending flexibility, no smelly feet, comfortable wearing and so on, and the friction coefficient is high on asphalt pavement, wet and snowy pavement. The waste SBS sole can be recycled and the cost is moderate. The sole style can be translucent beef tendon sole or colorful two-color sole, or it can be made into foam sole. The cheap integral molded canvas shoes made of SBS are lighter 15-25% than PVC resin shoes, with a higher friction coefficient of 30%, and have excellent wear resistance and low-temperature flexibility. SBS has these excellent properties, which make it widely used in footwear industry.
China is the largest production and consumption market of footwear products in the world, and the shoe material market will remain the main target market of SBS in China for quite some time to come. After China's entry into WTO, the export quota of footwear will be abolished and the export advantages will be fully exerted. In order to eliminate the imbalance between the eastern and western regions, the state began to increase investment in the western region to accelerate its economic development. In the next few years, with the rapid economic development in the western region and the improvement of people's living standards, the demand for shoes made of TPR(SBS shoes) will increase year by year. In addition, the accelerated opening of the western economy will attract the transfer and development of footwear to the west, thus driving the demand for SBS in the whole western market. In 2003, the consumption of SBS in China's footwear industry was about 210.3 million tons, and it is expected to reach 247 thousand tons in 2008, with an average annual growth rate of about 3% from 2003 to 2008.
Asphalt modification
The application of SBS in asphalt modification includes waterproofing membrane asphalt modification and road asphalt modification. SBS modified asphalt waterproofing membrane has the characteristics of good low-temperature flexibility, good self-healing ability and durability, high-temperature flow resistance, aging resistance, thermal stability and impact resistance, which can greatly improve the performance of waterproofing membrane and prolong its service life, and can meet the needs of important buildings and structures. It has been widely used in municipal engineering including bridge deck (concrete), subway, underground passage, and water conservancy engineering including pools and canals.
At present, there are many manufacturers of modified asphalt waterproofing membrane in China, including 15 production lines of modified asphalt waterproofing membrane introduced and put into operation, and more than 50 production lines independently developed in China, with a total production capacity of about1.400 million m2/ year. In 2003, the actual consumption of SBS was about 63,700 tons. With the massive investment and acceleration of infrastructure construction in China, the development prospect of modified asphalt in China is good, and the demand for SBS will increase accordingly. It is predicted that the consumption of SBS in modified asphalt will reach165438+200,000 tons in 2008, and the average annual growth rate from 2003 to 2008 is about 12%.
Polymer modification
SBS is a good resin modifier, which can be mixed with PP, PE, PS, ABS and other resins to improve the impact resistance and flexibility of products. These products are mostly used in electrical components, automobile steering wheels, bumpers, seals and so on. Compared with foreign developed countries and regions, China's polymer modification industry is still in its infancy. In 2003, the consumption of SBS in polymer modification in China was about 1650 tons. With the development of China's automobile industry and home appliance industry, consumers' requirements for comfort, safety and durability of products will gradually increase, and with the rapid development of China's synthetic resin industry, the domestic polymer modification industry will flourish.
It is predicted that from 2003 to 2008, the application of SBS products in polymer modification in China will increase rapidly at a rate of more than 20%, and it will reach the level of 45,000 tons in 2008.
agglutinant
SBS has good solubility, fast dissolution, good stability and strong cohesion in hydrocarbon solvents, which avoids the harm of aromatic solvents to human health. In addition, SBS adhesive has good elasticity, bonding strength and low temperature performance, and its low viscosity and creep resistance are better than those of ordinary EVA and acrylic adhesives, so it is widely used in life. It can be used to produce adhesives for shoes, metallurgical powder molding agents, laminating adhesives, wood dry adhesives, labels, adhesive tapes, disposable sanitary products, laminating adhesives, sealants, hooks, electronic components, universal super adhesives, all-purpose adhesives and self-adhesive tapes.
In 2003, the actual consumption of SBS in China's adhesive industry was about 43,700 tons. It is estimated that the demand will reach 87,000 tons by 2008, and the average annual growth rate of demand from 2003 to 2008 is about 14.7%.
Other fields
SBS can also be used as the main raw material for toys, furniture and sports equipment. Used as floor material, car seat cushion material, carpet bottom layer and sound insulation material, wire and cable sheath. In addition, SBS can also be used in cement processing, automobile manufacturing, interior decoration of houses and the manufacture of various rubber hoses, which are used in bright oil, medical devices, household appliances, pipe belts, wires and cables.
In 2003, the domestic consumption of SBS in other fields was about 1.3 1 10,000 tons. It is estimated that it will reach 50,000 tons by 2008, with an average annual increase of more than 30%.
3 process overview
SBS is produced from styrene and butadiene. Anionic solution polymerization process with lithium initiator is used in industry, and the polymer solution becomes a solid product after coagulation and solvent removal. The conventional production method adopts batch polymerization and wet coagulation process.
At present, foreign manufacturers are committed to developing continuous polymerization technology and dry coagulation process. Compared with the current batch polymerization technology, continuous polymerization technology has the characteristics of high production efficiency, stable product quality and low material and energy consumption. Conventional wet coagulation process needs a lot of water, energy and sewage, and may increase the gel content in the product, while dry coagulation process can overcome many defects of wet coagulation process, which is a revolution in synthetic rubber industry.
Domestic SBS production technology has reached a certain level after more than 20 years of development. In 2003, the production capacity of SBS plant built with domestic technology was 65438+600,000 tons/year. Domestic SBS production equipment adopts batch polymerization and wet coagulation process, and continuous polymerization process is still under development. In the past few years, domestic SBS products have some problems, such as unstable quality between batches, dark color and high melting temperature. In recent years, this problem has been basically solved, and the quality of SBS products produced by domestic technology has been greatly improved, which is basically close to the quality of similar products abroad, and its competitiveness has been improved.
4 problems and suggestions
Although China has made great progress in SBS R&D, built two sets of 10,000-ton production facilities, owned a complete set of self-developed technologies, and successfully transferred the complete set of technologies to Italian Enichem Elastomer Company and China Taiwan Province Synthetic Rubber Co., Ltd., there is still a certain gap in terms of material consumption, energy consumption, varieties and brands compared with foreign advanced technologies. Therefore, in the long run, China needs to further increase the investment in scientific research in SBS field, further improve the technical level of material consumption, energy consumption, production continuity and process control, and strive for greater breakthroughs in product application and development, variety and brand diversity, so as to enhance the overall competitiveness of China's SBS industry in participating in the international market.
At present, the satisfaction rate of SBS in China's domestic market is only about 50%, and it may be lower with the increase of demand in the future. This has laid a good market foundation for the development of SBS in China. But I should see that at present, the work of further capacity expansion of SBS plant in Beijing Yanshan Petrochemical Company Synthetic Rubber Plant and Yueyang Baling Petrochemical Company Synthetic Rubber Plant has been started. Some domestic regions and enterprises are also stepping up the preliminary research work of SBS project, and it is expected that the production capacity of SBS production equipment in China will be greatly improved in the next few years. At the same time, the domestic market will be impacted by products from China, Taiwan Province, South Korea and Japan, and the competition between SBS at home and abroad will become increasingly fierce. Therefore, new equipment must have competitive advantages in product performance and production cost in order to survive and develop in the competition.
At present, SBS abroad is mainly used to produce adhesives and asphalt modifiers, while domestic SBS products are mainly used to produce low-grade shoe materials. It is urgent to develop new uses and brands of SBS. With the massive national capital investment and the acceleration of high-grade highway construction, SBS is an important potential market for road asphalt modification. After the project is put into production, it is necessary to further strengthen scientific research, strengthen cooperation with asphalt production enterprises and road construction departments, develop SBS modified road asphalt series suitable for domestic reality as soon as possible, and occupy this new application field.
Seeking adoption is a satisfactory answer.