Engineering plastics generally refer to plastic materials that can bear mechanical stress as structural data and can be used in a wide range of temperature planning and a more rigorous chemical and physical environment. It can be divided into general engineering plastics and special engineering plastics. General engineering plastics usually refer to the five kinds of plastics that have been industrialized and widely used in planning, namely polyamide (nylon, PA), polycarbonate (polycarbonate, PC), Polyoxymethylene (POM), polyester (mainly PBT) and polyphenylene oxide (PPO). While special engineering plastics refer to some plastics with more excellent and unique functions, but most of which have not been planned for industrialized production or have small production planning and relatively narrow use, such as polyphenylene sulfide (PPS), polyimide (PI), polysulfone (P), polyetherketone (PEK), liquid crystalline polymer (LCP), etc.

Engineering plastics can replace metal as structural data, so they are widely used in the fields of electronics, transportation, mechanical equipment and daily necessities, and their position in the national economy is becoming increasingly prominent.

Development of domestic production

The skill development of engineering plastics in China has a history of nearly 40 years. Although it has a certain skill base, it is still far away from foreign countries in terms of skill level, production capacity and output value. Some varieties (such as PPO) are still basically blank.

In terms of business planning, most of China' s engineering plastics enterprises are 1000 grade production equipment or industrial test equipment, while the annual production capacity of foreign enterprises is more than 10000 grade. The huge differences in planning and process level make it difficult for domestic engineering plastics to meet the needs of domestic shopping malls, and the product functions and can not compete with imported products.

Characteristics and uses

Polyamide (PA) has won people' s attention because of its unique low specific gravity, high tensile strength, wear resistance, good self lubrication, excellent impact toughness, and the function of both rigid and flexible. In addition, it is easy to process, high efficiency, light specific gravity (only 1/7 of metal), and can be processed into various products to replace metal. It is widely used in cars and transportation industry. Typical products include pump impeller, fan blade, valve seat, bushing, bearing, various exterior plates, car electrical appearance, cold and hot air control valve and other parts. About 3.6~4 kg of nylon products are consumed for each car. The consumption proportion of polyamide in the car industry, followed by electronics and electricity.

Although polycarbonate (PC) is a thermoplastic resin, it not only has the strength similar to non-ferrous metals, but also has ductility and strong toughness. Its impact strength can not be damaged by hammering, and can fully enjoy the TV screen. The transparency of polycarbonate is excellent, and any coloring can be applied. Because of the above functions of polycarbonate, it has been widely used in various lampshades, signal lights, bright protective panels of gymnasiums and stadiums, lighting glasses, high-rise buildings, car mirrors, windshield panels, aircraft cabin glass, and motorcycle driving hats. The shopping malls used are computers, office equipment, cars, glass and sheets. CD and DVD discs are one of the potential shopping malls.

Polyoxymethylene (POM) is known as "super steel" because it has superior mechanical and chemical functions. Therefore, it can be used as data that many metal and non-metal data can' t do. It is mainly used as various small module gears with high degrees, complex external parts, tap water and explosion pipeline valves. The use of polyoxymethylene in agricultural sprinkler irrigation machinery in China can save a lot of copper.

Polybutylene terephthalate (PBT) is a thermoplastic polyester. Compared with other thermoplastic engineering plastics, non reinforced PBT has better processing and electrical functions. The PBT temperature is low. When the mold temperature is 50 ℃, it can crystallize rapidly and the processing cycle is short. Polybutylene terephthalate (PBT) is widely used in electronics, electrical and car industries. Because of its high insulation and temperature resistance, PBT can be used as flyback transformer of TV, distributor and ignition coil of car, shell and base of office equipment, various external parts of car, fan of air conditioner, base of electronic stove and shell of office equipment.

Polyphenylene oxide (PPO) resin has physical and mechanical functions, heat resistance, electrical insulation, low moisture absorption, high strength, good dimensional stability, and creep resistance at high temperature, which is different from all thermoplastic engineering plastics. It can be used in washing machine compressor cover, vacuum cleaner housing, coffee utensils, hair styling machine, hair dryer, microwave oven utensils and other small household appliances. Modified polyphenylene oxide is also used in TV components, connectors of teletype equipment, etc.

Demand status and forecast

With the rapid development of China' s national economy, the demand for engineering plastics in all walks of life in China has increased rapidly, especially in the domestic emerging industries, national pillar industries and new growth point industries, such as electronics, cars, transportation, building materials, packaging, equipment and human body, which require engineering plastics with many functions, so that the demand for engineering plastics in China has increased rapidly in recent years. In recent years, the demand for engineering plastics in China has increased rapidly, with an average annual growth rate of 25. In particular, the average annual growth rate of PBT, nylon and PPO has exceeded 25.

According to the changing rules of the apparent demand of several engineering plastics in the previous history, combined with the world planning and the market trend, the demand of five general engineering plastics is guessed respectively. There is no good rule to follow for PBT resin due to the demand change in the previous history. Therefore, based on the corrected apparent demand in 1998, and assuming that the future demand development is synchronized with the increase of GDP, the apparent demand in the next few years is predicted. By 2000 and 2005, the apparent consumption of general engineering plastics in China will reach 338000 and 528000 respectively. The average annual growth rate from 1999 to 2005 was 9.8 per cent. From 2003 to 2004, the apparent consumption of polycarbonate may exceed that of polyamide and become a general engineering plastic in China. By 2005, the demand for polyamide is 179000, polycarbonate is 205000, polyformaldehyde is 126000, PBT is 11900 and modified polyphenylene oxide is 6600.

In the near future, the five general engineering plastics are modified polyphenylene oxide, followed by polycarbonate, followed by polyamide, PBT and polyoxymethylene resin. But the order of different prehistoric periods is slightly different.

Carry out the mission

In the future, the main mission of China' s engineering plastics development is to focus on breaking through the difficulties in the production skills of polycarbonate and polyformaldehyde resin, and build 1~2 sets of large-scale production equipment; Develop the application market of general engineering plastics and its composite materials, give play to the processing ability of engineering plastics and improve the processing quality; Strengthen scientific and technological development, strive to solve the key problems in the industrial production of polyphenylene oxide and special engineering plastics represented by polyphenylene sulfide and liquid crystal polymer, and complete the industrial production of polyphenylene oxide, polyphenylene sulfide, liquid crystal polymer and polyimide, so as to lay an outstanding foundation for the further development of new chemical materials in China.

Source: Jiangmen engineering plastics http://www.wywantong.com/