I. Status of industry
In recent years, the output of adhesives in China has grown rapidly. From 1999 to 2001, the total output of adhesives and sealants nationwide increased from 2.27 million tons to 2.61 million tons, respectively, with an average annual growth rate of 7.7%. The annual sales growth rate exceeded the growth rate of production and became One of the fastest growing industries in China's chemical industry.
At the same time, new products continue to emerge, and some modified, grafted, copolymerized, and specialty adhesives have been developed one after another, and some have been industrialized. Such as polyurethane modified polyvinyl acetate emulsion, frost-resistant white latex, double horse modified epoxy conductive adhesive, silicone modified epoxy resin structural adhesive, polyurethane modified epoxy resin adhesive, micro bubble type room temperature curing single Component polyurethane adhesive, flame-retardant polyurethane potting compound, re-sticky ball-shaped acrylic pressure-sensitive adhesive, silicone pressure-sensitive adhesive and adhesive tape, etc. These products have many excellent properties, not only meet various needs, Moreover, it has improved the grade of adhesive products in China and replaced some imports.
Adhesive production technology has also made great progress. The application of new production processes such as radiation, UV-curing, and interpenetrating network methods has played an important role in improving product performance and improving product quality. Adhesive production equipment has also been greatly improved and updated, polymerization reactors are becoming larger, continuous and automated. For example, the volume of the emulsion polymerization tank of BASF's dyeing and chemical plant has reached 36 cubic meters, and all of them are controlled by computers; the 7 cubic meter emulsion polymerization semi-circular tube jacket reactor designed and manufactured in China has a good effect; the coating machine and the cutting machine have been applied. Achieve international medium level, width up to 1.3 to 2.0 meters, coating speed up to 120 to 150 meters/minute; static elimination technology (electrostatic separation tube), tension automatic control device, high sensitivity sensor, FM frequency modulation system, etc. The kind of self-control facilities have also been gradually developed and put into production operations.
The field of adhesive application has been continuously expanded. It has been used mainly in the fields of wood processing, construction and packaging, and has expanded into many fields such as clothing, light industry, machinery manufacturing, aerospace, electronics, transportation, medical and health, post and telecommunications, and warehousing. Especially in recent years, China's trademarks, labels, and advertisements have been used extensively to accelerate the development of corresponding adhesives. The amount of glue used in the automotive industry, electrical and electronics, footwear, construction, and food packaging industries has grown rapidly.
Second, the problem to be solved
Although China's adhesive industry has made considerable progress, the current problems are still very prominent, mainly reflected in:
(1) Dispersed production enterprises, backward technology, few varieties, and low quality and grades. According to incomplete statistics, there are nearly 2,000 adhesive production enterprises in China, distributed in 28 provinces, autonomous regions, and municipalities directly under the central government, but only 100 companies are on the scale and top level.
(2) Product aging, slow replacement, application research and after-sales service can not keep up. Most companies only compete for the market with prices on some old products, and the research and development of some urgently needed high-tech products lags behind. General-purpose adhesives such as acrylic pressure-sensitive adhesive emulsions applied to BOPP film packaging tapes, used in the production of styrene-acrylic, vinegar-acrylic and acrylic-type emulsions for general architectural coatings, general-purpose white latex, and EVA-type heat for bookbinding wirelessly Melt glue, general-purpose 502 cyanoacrylate and silicone rubber, etc., the production capacity greatly exceeds the demand, and the competition is fierce. However, some high-performance, high-quality adhesives and auxiliaries cannot be produced, or the performance and quality of the products cannot meet the requirements for use. For example, the research on the water-based chemistry of environment-friendly neoprene and polyurethane adhesives has been carried out in China for many years, but so far. Still no commercial production.
(3) The main raw materials and related auxiliaries of some adhesives are in short supply and cannot be produced or the quality and performance of the products cannot meet the requirements. For example, EVA, SIS resin, PA resin for hot-melt adhesives and hot-melt pressure-sensitive adhesives, TPU resin for footwear, and some additives for adhesives must be imported from foreign countries in whole or in part. According to statistics, in 2001 China imported a total of 152,200 tons of various types of adhesives and sealants and its raw and auxiliary materials, mainly polyurethane rubber, polyurethane structural sealant, epoxy resin adhesive, polyamide resin adhesive, high-performance silicone sealant, High-performance acrylic adhesives and pressure-sensitive adhesives, as well as a considerable number of adhesive raw materials and related additives.
(4) Polyvinyl alcohol formaldehyde adhesive (107 glue), which is mainly used for building decoration and wood processing industry, has been banned in developed countries because it contains free formaldehyde and damages human health. However, due to its low price, China's current usage is still relatively large. .
(5) The production technology of urea-formaldehyde rubber, which is the largest synthetic adhesive in China, is low, and the amount of formaldehyde released from the product is 4-5 times higher than the international standard, which is harmful to consumers' health. At present, there are only a few manufacturing enterprises in China, especially the foreign-made formaldehyde content of urea-formaldehyde rubber produced by foreign-funded enterprises has dropped below 0.1%.
(6) Neoprene is a traditional bulk adhesive in China. The adhesive is mainly used in shoemaking, decoration industry and wood industry. Neoprene contains a large number of toxic and harmful organic solvents, and has poor adhesion to soft PVC thermoplastic elastomers, polyurethanes and other new footwear materials. It has not been adapted to the needs of the footwear industry. In the developed countries, footwear adhesives have been completely Use polyurethane adhesive and hot melt adhesive.
Third, the future trend
In the next 5 to 10 years, China's adhesive production and sales will continue to grow rapidly. By 2005, the output is expected to reach 3.54 million tons, with an average annual growth rate of 7.8%. In addition, with the continuous improvement of production technology, some high-performance, high-quality, high-value-added new products have been put into operation one after another. With the continuous expansion of application fields, it is expected that the growth rate of adhesive sales in China will still be higher than the increase in output. This is undoubtedly good news for manufacturers.
With the increasingly stringent environmental protection regulations in China, people's awareness of environmental protection has been increasingly strengthened, and environmentally-friendly adhesives are and will continue to be the mainstream of synthetic adhesives.
——The large-scale and large-scale enterprises of adhesive production are concentrated. With the increasingly fierce market competition, users' requirements for product quality and performance are also increasing. Workshop-style small-scale production enterprises will be eliminated. Synthetic adhesive production will be concentrated at the upper level and upper-scale enterprises.
- Waterborne rubber has a bright future. Water-based glue does not contain organic solvents and has no pollution. It is an environmentally friendly adhesive, and it is also one of the rapidly growing types of glue. Water-based polyurethane adhesives (for composite films, automotive interiors, etc.), reactive adhesives (for automotive lights, parts, household appliances, plastic parts, etc.), and 100% liquid reactive PU adhesives (structural bonding) should be developed. , high-performance (such as non-primed) automotive windshield glass adhesive sealant, composite film polyurethane foam for cooking bags (product performance to the international level, such as Japan AD502, etc.) and its associated cross-linking curing agent, thixotropic agent, etc. .
- Rapid development of hot melt adhesives and hot melt pressure sensitive adhesives. The hot-melt adhesive has no pollution, rapid curing, wide adhesive surface, is suitable for continuous production, and is easy to store and transport. It has been rapidly developed in recent years and is the fastest-growing rubber in China. According to statistics, in 2000 and 2001, the total output of hot-melt adhesives and hot melt pressure-sensitive adhesives in the country was 58,000 tons and 65,000 tons, respectively. These environmentally-friendly types of adhesives are the fastest-growing adhesives.
- High-performance adhesives will develop rapidly. According to the market demand, in the future, the development focus of high-quality, high-performance adhesives in China will focus on modified acrylic adhesives, polyurethane adhesives, epoxy adhesives, and organic silicone adhesives, followed by a viscous ball-shaped acrylic pressure-sensitive adhesive ) High-strength modified acrylic adhesives, pressure-sensitive adhesives and tapes. Such as peeling strength ≥ 12N/cm pressure sensitive tape.
—— Adhesive products that need to be actively researched and developed include: epoxy or polyurethane-modified acrylate adhesives, special pressure-sensitive adhesives and adhesive tapes, such as high-grade medical pressure-sensitive adhesives and products (such as surgical towels, wound stickers, etc.); Polyurethane resin raw materials, resistant to cooking type, especially non-toxic aliphatic isocyanate PU structural adhesive, reactive hot melt adhesive, water-based PU adhesive and PU sealant. In addition, some auxiliary agents, such as non-discoloring curing agents, special catalysts, dehydrating agents, thixotropic agents, etc.; epoxy structural adhesives for electronic and aerospace and construction industries, and new modified epoxy resin adhesives And its supporting curing agent; high performance modified silicone sealant, silicone pressure sensitive adhesive and tape.
Source: China Garment Network