Polytetrafluoroethylene (Polytetrafluoroethylene, abbreviated as PTFE), commonly known as "Plastic King", is a tetrafluoroethylene as a monomer polymerisation of polymers, the chemical formula is (C2F4)n, heat and cold resistance is excellent, can be used for a long period of time in the -180 ~ 260ºC. It can be used for a long time at -180 to 260ºC. This material is resistant to acid, alkali and all kinds of organic solvents, almost insoluble in all solvents. At the same time, PTFE has the characteristics of high temperature resistance, its coefficient of friction is extremely low, so it can be used as lubrication, but also become the ideal coating for the inner layer of easy-to-clean water pipes.

Basic information

Main applications

1.Application in anti-corrosion and anti-wear According to relevant statistics of developed countries, in today's industrialized countries, the annual economic loss caused by corrosion accounts for about 4% of the total output value of the national economy. A considerable number of accidents in chemical production are caused by chemical reactions caused by equipment corrosion and medium leakage. It can be seen that the loss and harm caused by corrosion is serious, and it has attracted widespread attention. PTFE material overcomes the corrosion resistance and poor flexibility of ordinary plastics, metals, graphite, ceramics and other shortcomings. With its excellent high and low temperature resistance and corrosion resistance, it can be used under harsh conditions of temperature, pressure and media. It has become the main corrosion-resistant material in petroleum, chemical, textile and other industries. PTFE pipes are mainly used as delivery pipes and exhaust pipes for corrosive gases, liquids, steam or chemicals. The push tube formed by PTFE dispersed resin is lined into the steel pipe to form a lining, or the PTFE push inner tube is wound with glass fiber to reinforce it, or the PTFE push tube is reinforced with steel wire braiding outside the push tube, and the liquid medium can be transmitted under high pressure, as It is an indispensable part of hydraulic transmission, and can greatly improve the rupture strength at high temperature and has good bending fatigue resistance. Because the coefficient of friction of PTFE materials is the lowest among known solid materials, this makes filled PTFE materials the most ideal materials for oil-free lubrication of mechanical equipment parts. For example, adding lubricating oil to equipment in papermaking, textile, food and other industrial fields is easy to contaminate the product, so filling PTFE material solves this problem. In addition, experiments have proved that adding a certain amount of solid additives to engine oil can effectively save about 5% of engine fuel oil.

2.Corrosion-resistant sealing material Another major application of PTFE in chemical industry is sealing material. Due to its good overall performance, PTFE is unmatched by any sealing material, and it can be used for sealing in various harsh occasions, especially when high temperature and corrosion resistance are required. PTFE tape has long fibers, high strength, high plasticity, and good calenderability. It can be completely sealed with a small pressing force. It is easy to operate and apply, and it is more efficient when used on uneven or fine-structured surfaces. , has good sealing performance and can improve corrosion resistance, expanding its scope of use. The sealing of the sliding parts uses PTFE packing, which can obtain good corrosion resistance stability, and it has a certain compressibility and resilience, and the resistance during sliding is small. Filled PTFE sealing material has a wide temperature range and is the main substitute for traditional asbestos gasket materials at present. It also has high modulus, high strength, creep resistance, fatigue resistance, high thermal conductivity, low coefficient of thermal expansion and friction coefficient, etc. Performance, adding different fillers can expand the scope of application.

3.Anti-adhesive application PTFE material has the smallest surface tension among solid materials, does not adhere to any substance, and also has excellent characteristics of high and low temperature resistance and non-toxicity. Therefore, PTFE is often used as an anti-stick lining for tableware as a coating. Liners for non-stick pans and microwave ovens. In the textile industry, a large number of chemical sizing materials are used for yarn sizing, especially when using styrene-butadiene lactate, acid methyl cellulose, polyvinyl acetate and other very viscous materials as sizing materials, serious sticking phenomenon will occur. It is necessary to remove the sticky scars to continue production, which not only increases the amount of labor Chemicalbook, but also reduces production efficiency and affects product quality. After using PTFE sticky rollers, the anti-sticking effect is remarkable. Similarly, it can also be applied to various Plastic packaging sealing machinery.

4.Electrical applications PTFE's inherent low loss and dielectric constant make it an ideal insulating material for wires and cables. The reason why PTFE is used as the wire coating layer: it has excellent electrical properties, its volume resistivity can reach 1017Ω, its surface resistivity is greater than 1016Ω, and it remains unchanged at 100% relative humidity; the dielectric constant is as low as 2.0, and the dielectric constant is as low as 2.0. The electric loss tangent is about 2×10-4 and has nothing to do with temperature frequency; good heat resistance, long-term use at 260 ° C, good insulation, can reach above H level; strong toughness and flexibility, even low The toughness is still not affected at -90°C; aging resistance, excellent weather resistance, high chemical stability; non-combustible and low smoke. Printed circuit substrates made of it have been widely used in the aerospace field, so PTFE products are especially suitable for many high-performance and challenging fields such as telecommunications, computers, test and measurement, and national defense.