Polyoxymethylene technology
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Does anyone have the operating procedures and PID diagrams for polyoxymethylene technology? Could you send them to me at YTWJH710526@YAHOO.COM.CN?
Polyformaldehyde is a thermoplastic crystalline polymer. Known as “supersteel,” it is also called polyoxymethylene. Its structure is such that the English abbreviation is POM. Typically, the polymers obtained from the polymerization of formaldehyde have a low degree of polymerization and are prone to depolymerization upon heating. Around 1955, DuPont Company produced the homopolymer of formaldehyde by polymerizing formaldehyde. Polyoxymethylene crystallizes very easily, with a crystallinity of over 70%. The melting temperature of homopolymerized formaldehyde is around 180°C. The scientific name for polyoxymethylene is polyoxymethylene polymer (abbreviated as POM). Polyoxymethylene is a linear polymer without side chains, featuring high density and high crystallinity, as well as excellent overall properties. Polyoxymethylene is a hard and dense material with a smooth, shiny surface; it is pale yellow or white in color, and can be used over extended periods at temperatures ranging from -40 to 100°C. Its wear resistance and self-lubricating properties are also superior to those of the vast majority of engineering plastics, in addition to having good oil resistance and peroxide resistance. It is very sensitive to acids, strong bases, as well as ultraviolet radiation from moonlight. Polyoxymethylene has a tensile strength of 70 MPa, low water absorption, dimensional stability, and a glossy finish – all properties that are superior to those of nylon. It is a highly crystalline resin and the toughest among thermoplastic resins. It possesses high heat resistance, high bending strength, and high fatigue resistance, as well as excellent wear resistance and electrical properties. Properties of polyoxymethylene:
Property values:
Density: 1.43
Melting point: 175°C
Tensile strength (yield): 70 MPa
Elongation at yield: 15%
(Elongation at break): 15%
Impact strength (notched): 108 KJ/m2
(Impact strength with notch): 7.6 KJ/m2
The synthesis of homopolymerized polyoxymethylene generally involves the condensation polymerization of an aqueous solution of formaldehyde in the presence of acid. a-Polyoxymethylene with a degree of polymerization of 100 or more is obtained, and then it is heated to decompose into formaldehyde gas. After purification and dehydration, the monomer is usually purified using a partial prepolymerization method, and subsequently polymerization is carried out in a dry solvent containing a small amount of initiator. The presence of water results in a significant decrease in molecular weight. Initiators can be Lewis acids or bases, etc. However, tertiary amines are mostly used for anionic addition polymerization, with the reaction proceeding as follows: The end groups of polyoxymethylene are hemiacetals (—CH2OH), and at temperatures above 100°C, these end groups tend to break apart; therefore, end-group treatment is generally required to stabilize them. After stabilization treatment, it can withstand temperatures up to 230 ℃. Polyformaldehyde can be processed at temperatures of 170–200 °C, such as by injection, extrusion, blow molding, etc. It is mainly used as an engineering plastic in automobiles, mechanical components, etc. www.seafar.cn Typical applications of POM polyoxymethylene: POM has a very low coefficient of friction and excellent geometric stability, making it particularly suitable for manufacturing gears and bearings. Due to its high-temperature resistance, it is also used in piping components (pipe valves, pump housings), lawn equipment, and more. Injection molding process conditions: Drying treatment: If the material is stored in a dry environment, drying treatment is usually not required. Melting temperature: 190~230 for homopolymer materials℃ ； The copolymer material is at 190~210°C. Mold temperature: 80~105°C. A higher mold temperature can be used to reduce the shrinkage rate after molding. Injection pressure: 700~1200 bar Injection speed: moderate to high injection speed. Flow channels and gates: Any type of gate can be used. If a tunnel gate is used, it is best to use a shorter type. For homopolymer materials, it is recommended to use a hot nozzle runner. For copolymer materials, either internal hot runners or external hot runners can be used. Chemical and physical properties of POM polyoxymethylene: POM is a tough and elastic material that retains excellent creep resistance, geometric stability, and impact resistance even at low temperatures. POM includes both homopolymer and copolymer materials. Homopolymer materials possess excellent ductile strength and fatigue resistance, but are difficult to process. Copolymer materials have excellent thermal stability and chemical stability, and are easy to process. Both homopolymer materials and copolymer materials are crystalline materials and do not absorb moisture easily. The high degree of crystallinity of POM results in a fairly high shrinkage rate, which can reach as much as 2% to 3.5%. Different enhanced materials have different shrinkage rates. Polyoxymethylene (POM) is an engineering plastic with excellent properties; it is known abroad as a material that can rival or even surpass steel. POM possesses metal-like hardness, strength, and rigidity; it exhibits excellent self-lubricating properties over a wide range of temperatures and humidity levels, good fatigue resistance, and elasticity. In addition, it also has good chemical resistance. At a cost lower than that of many other engineering plastics, POM is replacing metals in various markets where they have traditionally been used; it is used to manufacture many components in place of zinc, brass, aluminum, and steel. Since its introduction, POM has been widely applied in fields such as electronics and electrical equipment, machinery, instruments, consumer goods, automobiles, building materials, and agriculture. In many new application areas such as medical technology and sports equipment, pom also shows good growth trends. Application consumption continues to grow. Pom performs exceptionally well in sliding and rolling mechanical components where high requirements are placed on lubricity, wear resistance, stiffness, and dimensional stability; as a result, it is primarily used in industrial machinery, automobiles, the electronics and electrical industry, plumbing fittings, and irrigation equipment. In recent years, China’s POM market has experienced rapid growth. In 2002, the apparent consumption volume of POM in China was 136,570 tons, and the average annual growth rate of apparent consumption in this market from 1990 to 2002 was 11.7%. It is estimated that China’s apparent consumption of Pom in 2005 will be 168,000 tons, with an average annual growth rate for apparent consumption in the Pom market from 2000 to 2005 reaching 10.3%. By 2010, the apparent consumption volume of Pom in our country is expected to rise to 197,000 tons, with an average annual growth rate of 3.2% for the Pom market during the period 2005–2010. The main factors contributing to the rapid development of the Pom market in our country include: the overall growth of the national economy, which leads to an expanding application market for Pom, one of the five major engineering plastics, with increasing demand for it ； In our country, the raw materials used for Pom production are inexpensive and readily available, resulting in substantial profits from Pom production and trade ； New breakthroughs are continuously emerging in the application fields of pom, such as the research and development of modified materials. Given the steady growth in market demand in our country, the price of Pom is expected to continue rising at a steady pace in the near future. The technological gap cannot be ignored. Although the market demand for Pom in our country is on the rise, due to the relatively late start of research and development related to Pom in our country, the domestic production scale, output, as well as the variety and quality of Pom fail to meet market demands. Compared with the advanced levels abroad, China’s pom production still faces issues such as high raw material consumption per unit, small plant scale, unstable quality, and a limited range of product grades. For example, DuPont’s consumption of formaldehyde per ton of homopolymerized Pom is 2.56 tons, with some reports indicating 3.08 tons; in contrast, the formaldehyde consumption per ton of Pom produced in China is 5–6 tons. Although this figure has decreased due to improvements, the gap remains significant. For many years, the production capacity and output of the Pom industry in our country have remained low, and these figures still fail to meet market demand. In 2002, there were only 3 Pom manufacturers in China, and among them, only Yuntianhua Group’s Pom production facility had a capacity of 10,000 tons per year (which has since been expanded to 20,000 tons per year). In 2002, China’s Pom production capacity was 12,800 tons per year, with a production volume of around 10,000 tons. From 1966 to 2002, the average annual growth rate of China’s Pom production capacity was 16.7%, while the average annual growth rate of output was 18.8%. It is thus evident that it is necessary to expand the production capacity of domestic Pom manufacturers. It is estimated that by 2005, there will be 6 POM manufacturers in China, with a total production capacity of 130,000 tons per year ； It is estimated that China’s Pom production capacity will be 190,000 tons per year in 2010, with an average annual growth rate of 7.9% for the period from 2005 to 2010. The reason why the increase in China’s Pom production capacity is not sufficient to meet market demand is that the domestic Pom market is growing rapidly, while China’s foundation for Pom production is relatively weak ； Furthermore, PM is a capital- and technology-intensive chemical product in the materials sector. China’s huge market has attracted the attention of foreign companies, which have been trying to gain a foothold in this market with their own products. Unwilling to transfer technology, they have slowed down the improvement of the technical level of domestically produced PM, preventing it from meeting the needs of consumers ； Furthermore, for a long time, China’s economic system and corporate management mechanisms have not conformed to the laws of a market economy; as a result, enterprises have been unable to obtain sufficient funding in a timely manner, which has hindered the development of Pom production. Imbalance in imports and exports Although China’s Pom production has increased, it still cannot meet the demands of the domestic market, resulting in the need to import large quantities of Pom each year. The main countries and regions from which China imports Pom are Japan, the United States, South Korea, and Taiwan Province of China, among others. In 2002, China’s import volume of Pom was 135,570 tons, and the average annual growth rate of Pom imports from 1995 to 2002 was 26.3%. Our country also engages in limited export trade of Pom on an annual basis; in 2002, 9,000 tons of Pom were exported. The development of high-tech industries and emerging sectors in our country has led to a significant increase in the demand for engineering plastics. As an engineering plastic suitable for various industries, pom has promising prospects for development. It is understood that there are several ongoing Pom construction projects in China at present; for example, the Pom project of DuPont-Asahi Kasei (Zhangjiagang) has already begun construction, while the planned Pom project at Shanghai Lanxing Chemical New Materials Factory is also in active progress. Given the situation of planned Pom projects in our country, it will be the trend for the development of the Pom industry there to introduce capital and advanced technical equipment to build Pom plants on a scale that is economically viable, in locations that possess the necessary raw material and technical foundations.
Property values:
Density: 1.43
Melting point: 175°C
Tensile strength (yield): 70 MPa
Elongation at yield: 15%
(Elongation at break): 15%
Impact strength (notched): 108 KJ/m2
(Impact strength with notch): 7.6 KJ/m2
The synthesis of homopolymerized polyoxymethylene generally involves the condensation polymerization of an aqueous solution of formaldehyde in the presence of acid. a-Polyoxymethylene with a degree of polymerization of 100 or more is obtained, and then it is heated to decompose into formaldehyde gas. After purification and dehydration, the monomer is usually purified using a partial prepolymerization method, and subsequently polymerization is carried out in a dry solvent containing a small amount of initiator. The presence of water results in a significant decrease in molecular weight. Initiators can be Lewis acids or bases, etc. However, tertiary amines are mostly used for anionic addition polymerization, with the reaction proceeding as follows: The end groups of polyoxymethylene are hemiacetals (—CH2OH), and at temperatures above 100°C, these end groups tend to break apart; therefore, end-group treatment is generally required to stabilize them. After stabilization treatment, it can withstand temperatures up to 230 ℃. Polyformaldehyde can be processed at temperatures of 170–200 °C, such as by injection, extrusion, blow molding, etc. It is mainly used as an engineering plastic in automobiles, mechanical components, etc. www.seafar.cn Typical applications of POM polyoxymethylene: POM has a very low coefficient of friction and excellent geometric stability, making it particularly suitable for manufacturing gears and bearings. Due to its high-temperature resistance, it is also used in piping components (pipe valves, pump housings), lawn equipment, and more. Injection molding process conditions: Drying treatment: If the material is stored in a dry environment, drying treatment is usually not required. Melting temperature: 190~230 for homopolymer materials℃ ； The copolymer material is at 190~210°C. Mold temperature: 80~105°C. A higher mold temperature can be used to reduce the shrinkage rate after molding. Injection pressure: 700~1200 bar Injection speed: moderate to high injection speed. Flow channels and gates: Any type of gate can be used. If a tunnel gate is used, it is best to use a shorter type. For homopolymer materials, it is recommended to use a hot nozzle runner. For copolymer materials, either internal hot runners or external hot runners can be used. Chemical and physical properties of POM polyoxymethylene: POM is a tough and elastic material that retains excellent creep resistance, geometric stability, and impact resistance even at low temperatures. POM includes both homopolymer and copolymer materials. Homopolymer materials possess excellent ductile strength and fatigue resistance, but are difficult to process. Copolymer materials have excellent thermal stability and chemical stability, and are easy to process. Both homopolymer materials and copolymer materials are crystalline materials and do not absorb moisture easily. The high degree of crystallinity of POM results in a fairly high shrinkage rate, which can reach as much as 2% to 3.5%. Different enhanced materials have different shrinkage rates. Polyoxymethylene (POM) is an engineering plastic with excellent properties; it is known abroad as a material that can rival or even surpass steel. POM possesses metal-like hardness, strength, and rigidity; it exhibits excellent self-lubricating properties over a wide range of temperatures and humidity levels, good fatigue resistance, and elasticity. In addition, it also has good chemical resistance. At a cost lower than that of many other engineering plastics, POM is replacing metals in various markets where they have traditionally been used; it is used to manufacture many components in place of zinc, brass, aluminum, and steel. Since its introduction, POM has been widely applied in fields such as electronics and electrical equipment, machinery, instruments, consumer goods, automobiles, building materials, and agriculture. In many new application areas such as medical technology and sports equipment, pom also shows good growth trends. Application consumption continues to grow. Pom performs exceptionally well in sliding and rolling mechanical components where high requirements are placed on lubricity, wear resistance, stiffness, and dimensional stability; as a result, it is primarily used in industrial machinery, automobiles, the electronics and electrical industry, plumbing fittings, and irrigation equipment. In recent years, China’s POM market has experienced rapid growth. In 2002, the apparent consumption volume of POM in China was 136,570 tons, and the average annual growth rate of apparent consumption in this market from 1990 to 2002 was 11.7%. It is estimated that China’s apparent consumption of Pom in 2005 will be 168,000 tons, with an average annual growth rate for apparent consumption in the Pom market from 2000 to 2005 reaching 10.3%. By 2010, the apparent consumption volume of Pom in our country is expected to rise to 197,000 tons, with an average annual growth rate of 3.2% for the Pom market during the period 2005–2010. The main factors contributing to the rapid development of the Pom market in our country include: the overall growth of the national economy, which leads to an expanding application market for Pom, one of the five major engineering plastics, with increasing demand for it ； In our country, the raw materials used for Pom production are inexpensive and readily available, resulting in substantial profits from Pom production and trade ； New breakthroughs are continuously emerging in the application fields of pom, such as the research and development of modified materials. Given the steady growth in market demand in our country, the price of Pom is expected to continue rising at a steady pace in the near future. The technological gap cannot be ignored. Although the market demand for Pom in our country is on the rise, due to the relatively late start of research and development related to Pom in our country, the domestic production scale, output, as well as the variety and quality of Pom fail to meet market demands. Compared with the advanced levels abroad, China’s pom production still faces issues such as high raw material consumption per unit, small plant scale, unstable quality, and a limited range of product grades. For example, DuPont’s consumption of formaldehyde per ton of homopolymerized Pom is 2.56 tons, with some reports indicating 3.08 tons; in contrast, the formaldehyde consumption per ton of Pom produced in China is 5–6 tons. Although this figure has decreased due to improvements, the gap remains significant. For many years, the production capacity and output of the Pom industry in our country have remained low, and these figures still fail to meet market demand. In 2002, there were only 3 Pom manufacturers in China, and among them, only Yuntianhua Group’s Pom production facility had a capacity of 10,000 tons per year (which has since been expanded to 20,000 tons per year). In 2002, China’s Pom production capacity was 12,800 tons per year, with a production volume of around 10,000 tons. From 1966 to 2002, the average annual growth rate of China’s Pom production capacity was 16.7%, while the average annual growth rate of output was 18.8%. It is thus evident that it is necessary to expand the production capacity of domestic Pom manufacturers. It is estimated that by 2005, there will be 6 POM manufacturers in China, with a total production capacity of 130,000 tons per year ； It is estimated that China’s Pom production capacity will be 190,000 tons per year in 2010, with an average annual growth rate of 7.9% for the period from 2005 to 2010. The reason why the increase in China’s Pom production capacity is not sufficient to meet market demand is that the domestic Pom market is growing rapidly, while China’s foundation for Pom production is relatively weak ； Furthermore, PM is a capital- and technology-intensive chemical product in the materials sector. China’s huge market has attracted the attention of foreign companies, which have been trying to gain a foothold in this market with their own products. Unwilling to transfer technology, they have slowed down the improvement of the technical level of domestically produced PM, preventing it from meeting the needs of consumers ； Furthermore, for a long time, China’s economic system and corporate management mechanisms have not conformed to the laws of a market economy; as a result, enterprises have been unable to obtain sufficient funding in a timely manner, which has hindered the development of Pom production. Imbalance in imports and exports Although China’s Pom production has increased, it still cannot meet the demands of the domestic market, resulting in the need to import large quantities of Pom each year. The main countries and regions from which China imports Pom are Japan, the United States, South Korea, and Taiwan Province of China, among others. In 2002, China’s import volume of Pom was 135,570 tons, and the average annual growth rate of Pom imports from 1995 to 2002 was 26.3%. Our country also engages in limited export trade of Pom on an annual basis; in 2002, 9,000 tons of Pom were exported. The development of high-tech industries and emerging sectors in our country has led to a significant increase in the demand for engineering plastics. As an engineering plastic suitable for various industries, pom has promising prospects for development. It is understood that there are several ongoing Pom construction projects in China at present; for example, the Pom project of DuPont-Asahi Kasei (Zhangjiagang) has already begun construction, while the planned Pom project at Shanghai Lanxing Chemical New Materials Factory is also in active progress. Given the situation of planned Pom projects in our country, it will be the trend for the development of the Pom industry there to introduce capital and advanced technical equipment to build Pom plants on a scale that is economically viable, in locations that possess the necessary raw material and technical foundations.
Dude, do you have a flowchart? Send me one
What is the latest production technology for polyoxymethylene?
There are no latest versions; they are all improved editions. But attention should be paid to the new technologies that will emerge in the second half of this year.
In fact, it is possible to introduce the specific applications of POM in products; for example, the zippers used in clothing are typically made of POM, and many components in various products are also made from this material. However, there are certain issues that arise during production related to the properties of POM as a raw material. This information can provide everyone with a clearer understanding and help, enabling consistent application in production control and when products are delivered
No~~~ That thing should be kept confidential, right?
This kind of information is absolutely confidential; in other words, it’s the formula!
Are there any principled techniques? A detailed one is also not needed. I need to prepare a feasibility study report, but there is no relevant information available. In distress~~~
Search online; there are industry reports on POM. Buy them if you want to
Polyoxymethylene (POM), an important engineering plastic. Consumption ratio: Electronics and electrical equipment 55%, automotive industry 15%, consumer goods 20%, industrial machinery 8%, others 2%. Due to low domestic production, the country relies mainly on imports to meet domestic market demand; import volumes have been increasing year by year in recent years, with figures of 63,400 tons, 90,600 tons, 108,300 tons, and 109,000 tons for the years 1998, 1999, 2000, and 2001 respectively. In our country, polyoxymethylene is primarily used in the electronics and electrical industry. In recent years, the electronics and electrical industry here has developed rapidly, and the automotive industry has gradually become a key industry in our country; as a result, the demand for polyoxymethylene will continue to increase. Main process steps in the production of copolymerized formaldehyde: 1. Formaldehyde concentration – Concentrating 40% wt industrial formaldehyde to a concentration of around 60% formaldehyde. 2. Production of trioxane (TOX): Under the action of acid catalysts, trioxane is synthesized from 60% formaldehyde; high-purity (99.99%) trioxane is obtained through crystallization and distillation. 3. Production of dioxolane (DOX): Dioxolane is synthesized from 60% formaldehyde and ethylene glycol, and high-purity (99.99%) dioxolane is obtained through concentration and distillation. 4. Polyoxymethylene (POM) production employs a Lewis-type cationic initiator, BF3-H2O, to copolymerize trioxymethane with dioxolane, using a twin-screw polymerization reactor. 5. POM granulation, pellet processing, and packaging: POM powder is subjected to stabilization treatment, extrusion granulation, degassing, heat treatment, and other processes to produce the final product, polyoxymethylene resin.