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PTFE Sheet Electrical Insulation Function

Yangzhong Tianyou Seals Co.,Ltd | Updated: Sep 21, 2017

PTFE Sheet Electrical insulation function

In the fluorine plastic polytetrafluoroethylene (PTFE) the largest consumption, the most widely used, is an important species in fluorine plastic. PTFE has excellent resistance to high and low temperature performance and chemical chaos, good electrical insulation, non-adhesive, weather resistance, flame resistance and good self-lubricating, "plastic king" reputation. The material was first developed for national defense and cutting-edge technology needs, and then gradually extended to civilian use, its use involves many aspects of aerospace and civil, is currently in its application has become an indispensable material.

      Features of PTFE

      PTFE is a polymer made from tetrafluoroethylene monomer, a transparent or opaque wax similar to PE having a density of 2.2 g / cm3 and a water absorption of less than 0.01%. Its chemical structure is similar to PE, except that all of the hydrogen atoms in the polyethylene are replaced by fluorine atoms. Because the CF key can be high, the function is not chaos, and thus its excellent chemical resistance, can withstand the addition of molten alkali metal, fluorinated medium and sodium hydroxide higher than 300 ℃, all strong acid (including aqua regia) , As well as the role of strong oxidants, reducing agents and various organic solvents; PTFE atoms in the F atom symmetry, CF bond in the two elements covalently bonded, there is no free electrons in the molecule, so that the whole molecule was neutral, so it Has excellent dielectric function, and its electrical insulation from the environment and frequency. Its volume resistance is greater than 1017  mm, dielectric loss is small, high breakdown voltage, good arc resistance, can work in the 250 ℃ electrical environment for a long time; because PTFE molecular structure without hydrogen bonds, structural symmetry, so it Of the crystallinity is very high (generally crystalline degree of 55% to 75%, sometimes up to 94%), so that PTFE heat resistance is excellent, the melting temperature of 324 ℃, decomposition temperature of 415 ℃, the maximum temperature of 250 ℃, The brittle temperature is -190 ° C and the heat distortion temperature (0.46 MPa) is 120 ° C.

     Polytetrafluoroethylene was called "Plastic King", the father of fluororesin Roy Prycote 1936 DuPont in the United States began to study the replacement of freon, they collected some of the tetrafluoroethylene stored in the cylinder, ready for the second Day for the next experiment, but when the next day to open the cylinder after the valve, but no gas spill, they thought it was leak, but the cylinder weighing, found that the cylinder did not lose weight. They saw the cylinder and found a lot of white powder, which was polytetrafluoroethylene.