The increasing maturity of domestic UMMWPE fiber processing technology, coupled with the decline in production costs and product prices, will drive the research and development of UHMWPE fiber products in the national defense and civil fields, thereby further stimulating the development of ultra-high molecular weight polyethylene fiber products, and expanding its market application range.
Ultra High Molecular Weight Polyethylene (UHMWPE) is a new type of thermoplastic engineering plastic. Its molecular structure is the same as that of ordinary polyethylene, but its viscosity average molecular weight can reach 1.5 million to 10 million.
The molecular chains of UMMWPE are very long, arranged in the same direction, and intertwined with each other. By strengthening the intermolecular interaction, the load can be transferred to the main chain more effectively, so UMMWPE has a high specific modulus and specific strength. UMMWPE also has excellent impact resistance, wear resistance, chemical corrosion resistance, low-temperature resistance, weather resistance, self-lubrication, etc. It is widely used in energy, chemical, textile, construction, metallurgy, and other fields.
In recent years, the two most prominent application fields of UMMWPE materials are UMMWPE fibers and UMMWPE lithium battery separators, and Nanjing Keya's twin screw extruder machine with a super large length-diameter ratio has outstanding performance.
UMMWPE fiber, aramid fiber, and carbon fiber are collectively known as the three major high-tech fibers in the world. The products are used in high-strength defense military equipment such as bulletproof and stab-proof equipment, as well as aerospace, marine industry, sports equipment, building reinforcement, and other industries.
Since the late 1990s in China, the research of production technology and equipment and pilot production of ultra-high molecular weight polyethylene fiber has been carried out. As one of the core equipment of fiber complete equipment, Nanjing Keya's ultra-large length-diameter ratio twin screw extruder machine has also achieved a series of major theoretical and practical breakthroughs, dedicated to the research and development of core technology and equipment manufacturing and industrialization of fiber pre-spun gel extrusion.
Nanjing Keya's ultra-large length-diameter ratio twin screw extrusion machines have been successively put into pilot trials and small-scale industrial production in some enterprises. After unremitting efforts, it has entered the stage of large-scale production, and now it has developed to the mass production scale of 6000t/a designed capacity of the factory, and the fiber performance of the final products has reached the international level.
At present, Nanjing Keya's twin screw extruder machines are installed in factories of more than 70% of fiber manufacturers in China, with stable operation, accurate control precision, high single-machine production capacity, and stable product quality.
Lithium-ion batteries are composed of positive and negative electrodes, an electrolyte, and a separator. An important function of the separator is to isolate the positive and negative electrodes and prevent the passage of electrons in the battery, while allowing the passage of ions, thereby completing the fast transfer of lithium-ion between positive and negative electrodes in the process of electrochemical charging and discharging. The performance of the separator directly affects the internal resistance, discharge capacity, cycle life, and safety performance of the battery. The thinner the separator and the higher the porosity, the smaller the internal resistance of the battery and the better the high-rate discharge performance. Therefore, the separator plays a very important role in improving the overall performance of the battery. Commercial lithium-ion batteries still mainly use polyethylene and polypropylene microporous membrane as the raw material for their separator. Especially in the field of power batteries, UMMWPE separators are widely used due to their outstanding performance.
The preparation methods of UMMWPE microporous membrane are divided into the dry method (melt-spinning and cold-stretching, MSCS) and the wet method (thermally induced phase separation, TIPS). Both methods include the extrusion step of UMMWPE or mixture, and then at least one orientation step makes the membrane produce pores and improve tensile strength. Nanjing Keya's ultra-large length-diameter ratio twin screw extrusion machine is the key equipment for this extrusion step. At present, mass production has begun in some membrane manufacturers.
Nanjing Keya's equipment research and development in the UMMWPE industry began in the early 1990s, and now it has developed and applied multiple specifications and models of twin screw extrusion machines with screw diameters ranging from 36mm to 125mm. The length-diameter(L/D) ratio can reach 68 to 72, which is an advanced level in China and even in the world. The research and development of Nanjing Keya's UMMWPE ultra-large length-diameter ratio extrusion machine have solved a series of technical problems and obtained several technical achievements and patents to meet the extremely high technological requirements of UMMWPE extrusion. At present, Nanjing Keya's ultra-large length-diameter ratio extrusion machine has occupied a major market share in the UMMWPE fiber industry and has begun to replace imported equipment in the membrane industry.
Related News
Tel: +86-25-52706155
E-mail: info@kymach.com
No.59 West Tianyuan Road, Jiangning, Nanjing, Jiangsu Province, China
English 
日本語 
한국어 
français 
Español 
русский 
português 
العربية 
中文
