Dongguan Mayor Yongying Insulation Materials Co., Ltd. is a private high-tech enterprise specializing in the production of PTFE sheets, PTFE films, PTFE rods, PTFE pipes, and other PTFE insulation products. The company's products are exported to more than 60 countries and regions such as Europe, America, and Southeast Asia, with stable quality and reliable performance, and have formed a brand effect. The company has passed ISO9001 certification and SGS environmental testing certification. Below, I would like to share with you the advantages of PTFE board manufacturers.
High temperature resistance: operating temperature up to 250 ℃.
Low temperature resistance: PTFE air filtration membrane has good mechanical toughness; Even if the temperature drops to -196 ℃, an elongation of 5% can be maintained.
Corrosion resistance: It exhibits inertness and resistance to strong acids, alkalis, water, and various organic solvents for most chemicals and solvents.
Climate resistance: has the best aging life among plastics.
High lubrication: It is the lowest friction coefficient among solid materials.
Non adhesion
PTFE air filtration membrane is the smallest surface tension in solid materials and does not adhere to any substance.
Non toxic
PTFE air filtration membrane has physiological inertness, and as an artificial blood vessel and organ, it has no adverse reactions after long-term implantation in the body.
The relative molecular weight of PTFE air filtration membrane is relatively large, ranging from hundreds of thousands to over 10 million, usually in the millions (polymerization degree is in the order of 104, while polyethylene is only in 103).
PTFE air filtration membrane
The crystallinity of PTFE air filtration membrane is generally 90-95%, and the melting temperature is 327-342 ℃. CF2 units in polytetrafluoroethylene molecule are arranged in zigzag shape. Since the fluorine atomic radius is slightly larger than that of hydrogen, the adjacent CF2 units cannot be completely trans cross oriented, but form a helical twisted chain, and the fluorine atoms almost cover the surface of the entire polymer chain. This molecular structure explains the various properties of PTFE. When the temperature is below 19 ℃, a 13/6 helix is formed; At 19 ℃, a phase transition occurs, and the molecules slightly unravel, forming a 15/7 helix.
Although the fracture of carbon carbon bonds and carbon fluorine bonds in perfluorocarbons requires energy absorption of 346.94 and 484.88 kJ/mol, respectively, the depolymerization of polytetrafluoroethylene to produce 1 mol of tetrafluoroethylene only requires energy of 171.38 kJ. So during high-temperature cracking, polytetrafluoroethylene mainly depolymerizes to tetrafluoroethylene. The weight loss rates (%) of polytetrafluoroethylene at 260, 370, and 420 ℃ are 1% per hour, respectively × 10-4, 4 × 10-3 and 9 × 10-2. It can be seen that polytetrafluoroethylene can be used for a long time at 260 ℃. Due to the production of highly toxic by-products such as fluorophosgene and perfluoroisobutylene during high-temperature cracking, special attention should be paid to safety protection and prevent polytetrafluoroethylene from coming into contact with open flames.
The friction coefficient of its mechanical properties is extremely small, only 1/5 of that of polyethylene, which is an important feature of perfluorocarbon surfaces. Due to the extremely low intermolecular force between fluorine carbon chains, polytetrafluoroethylene is non viscous.
It does not melt at a temperature of 250 ℃ and does not become brittle at ultra-low temperatures of -260 ℃. Polytetrafluoroethylene is exceptionally smooth, even ice cannot compare to it; It has excellent insulation performance, and a thick film of newspaper is enough to withstand high voltage of 1500V.
Polytetrafluoroethylene maintains excellent mechanical properties over a wide temperature range of -196-260 ℃, and one of the characteristics of perfluorocarbon polymers is that they remain brittle at low temperatures.