久久99精品,欧美日韩人妻精品一区二区,亚洲AV无码一期二期三期少妇,欧美国产一区二区亚瑟

Navigation

Industry news

PTFE is so widely used, it is truly the "king of plastics"!
Author:Dongda Environment Time:2020-12-23 Clicks:145
       Polytetrafluoroethylene (PTFE) is currently the most widely used fluoropolymer. It is the most chemically resistant plastic, has the best dielectric properties and a wide operating temperature range. It is called the "Plastic King".
       PTFE has high temperature resistance (it can be used in the temperature range of 200~260℃ for a long time), low temperature resistance (it can be used for a long time below -100℃), corrosion resistance (high chemical inertness), weather resistance (high resistance Atmospheric aging performance), high lubrication (with a very small coefficient of friction), non-adhesion (very low surface tension, not easy to adhere), good human compatibility (with good physiological inertia, non-toxic), electrical insulation Good (high insulation and not affected by temperature and humidity) and a series of advantages, these characteristics of PTFE are closely related to its molecular configuration.
       The molecular structure of PTFE is similar to polyethylene. It is a symmetrical and non-branched linear polymer, so the molecule is not polar, as shown in the following figure:
       Because the unbonded fluorine atoms in the molecules repel each other strongly, the carbon chain of PTFE is twisted into a spiral structure, and the fluorine atoms just completely cover the main chain of carbon atoms, which prevents the carbon atoms from interacting with other substances. react. In addition, the fluorocarbon bond has a very high bond energy of 466KJ/mol, which is the highest bond energy among all chemical single bonds, so the stability of PTFE is very high.
       However, PTFE also has its own shortcomings, which are mainly manifested as cold flow, large linear expansion coefficient, thermal conductivity, wear resistance, creep resistance, and outstanding surface non-stickiness. These shortcomings of PTFE make it used in Restricted to a certain extent.
       my country is one of the earliest countries in the research and production of PTFE, but in the past it was mainly based on the application of foreign technology for some simple processing, with less in-depth research, and the overall production level and process technology were not high. With years of accumulation and development, especially in the last ten years, the technical level of my country's fluorine chemical industry has developed rapidly. At present, 14 domestic enterprises, including Dongyue, Chenguang, Sanaifu, Juhua, and Meilan, produce PTFE, and 5 have a production capacity of more than 10,000 tons. Since the properties of PTFE are so special, in which areas is it usually used?
       Chemistry field
       PTFE neither dissolves nor swells in any known liquid, so the size of PTFE parts remains unchanged in any corrosive medium, no matter how long they are used. Large thin-walled containers made of PTFE are widely used in the actual operation of laboratories and factories that use corrosive liquids. In addition, they are also widely used in seals, pipeline linings, pumps, valves, etc.
       Machinery field
       No matter what kind of mechanical equipment, the mutual sliding surfaces need to be lubricated during operation to reduce the friction factor, reduce the wear and heat of the parts, and ensure the normal operation ability, accuracy and power consumption of the mechanical equipment. PTFE's low friction coefficient and self-lubricating properties make it widely used in the manufacture of bearings, piston rings, machine tool guides and sealing materials. However, due to its relatively high cost, it is usually used in precision instruments or environments that require acid and alkali resistance.
       Electrical field
       PTFE has excellent dielectric properties that do not actually depend on the influence of temperature and frequency, and at the same time has extremely high thermal stability, so it has become an irreplaceable electrical insulating material, especially in high-frequency, high-temperature and humid environments. in.
       Nowadays, various forms of PTFE materials play an important role in the field of electrical and electronic insulation. PTFE varnished glass cloth and glass cloth are used to make high-temperature and high-frequency insulating materials, which can be used in satellite communications and computers; PTFE films are used to make capacitors, as insulating layers, gaskets, cables, etc. between instruments; PTFE thin films of different calibers The wall pipes are respectively used to lead out the line bushings, heat shrinkable pipes and spiral pipes, and insulated water pipes of generators.
       Construction sector
       PTFE membrane structure is a brand-new form of building structure, which integrates architecture, structural mechanics, fine chemical engineering, material science and computer technology, etc., with high technical content.
       By coating PTFE resin on the ultra-fine glass fiber fabric, the PTFE membrane material is light in weight, high in strength, fire and flame retardant, self-cleaning, not affected by ultraviolet rays, fatigue resistance, distortion resistance, aging resistance, long service life, and high Features of light transmittance and low heat absorption. It is precisely because of the invention of this cross-epoch membrane material that the membrane structure building has become a modern permanent building.
       At present, the development and application of this kind of membrane materials abroad are relatively mature, and there are many manufacturers, such as Mehler and Verseidag in Germany, Taiyoko-gyo in Japan, Zhongxing Chemical Industry Co., Ltd., Chemfab in the United States, and ObeiKan in Saudi Arabia.
       medical field
       PTFE is water-resistant, physiologically inert and non-sticky, so it is used in many tissue repair materials and artificial organ materials, such as artificial blood vessels and heart repair membranes. Moreover, the biggest advantage of PTFE is that it can be sterilized by any method. It will not be denatured by autoclaving or treatment with various disinfectants. Therefore, it is widely used in medical equipment such as sutures, sterilization pads, and injection needles.
Whatsapp Phone QR code

Telephone

0086-0575-87139000

Scan and follow us

亚洲视频不卡| 欧美日韩国产区| 一级少妇精品久久久久久久| 玖玖在线视频| 欧美黑白大战在线观看蜜桃| 日韩36页| 丁香五月网| 国产91日韩| www.236868.com| 欧美小泬99精品1区2区3| 17草国产成人剧情在线| 新婚之夜玩弄人妻系列| 欧美性爽xxxzzzzzzzz| 高清电视| 国产免费无遮挡| 国产精品视频在线| 国产偷v国产偷v亚洲高清学生| 蚌埠市| 久久精品亚洲无码| 国产乱人伦精品一区二区无码| 无码国产69精品久久久久孕妇| 天堂最新版中文在线天堂| 欧美日韩人妻| 丁香五月一区二区三区| 亚洲欧洲精品mv免费看| 一区二区三区电影在线观看| 国产一区二区精品丝袜| 韩国午夜福利在线| 国产精品久久久免费视频| 国产黄在线观看免费观看 | 天堂影院在线观看| 孕妇av| 后入极品少妇| jzzijzzij欧洲成熟少妇| 99不卡| 欧美熟妇一区二区三区| 一区二区黄色片| 老师扒下内裤让我爽了一夜视频| 国产人伦精品一区二区三区| 亚洲日本99| 中文人妻无码|