Zhuopu answers for you: the three major properties of tetrafluoro

Tetrafluoroethylene is a polymer of tetrafluoroethylene, abbreviated as PTFE. The basic structure of polytetrafluoroethylene is- CF2- CF2- CF2- CF2- CF2- CF2- CF2- CF2- CF2- CF2- CF2-. Polytetrafluoroethylene is widely used in various industries that require acid, alkali, and organic solvents. It is not toxic to humans, but one of the raw materials used in the production process, ammonium perfluorooctanoic acid (PFOA), is believed to have carcinogenic effects. Polytetrafluoroethylene can be formed by compression or extrusion processing; It can also be made into water dispersions for coating, impregnation, or fiber production. Polytetrafluoroethylene is widely used in industries such as atomic energy, aerospace, electronics, electrical, chemical, mechanical, instrumentation, construction, textile, food, etc. as a high and low temperature resistant, corrosion-resistant material, insulation material, anti stick coating, etc.

mechanical property

Its friction coefficient is small, only 1/5 of polyethylene, which is an important feature of the perfluorocarbon surface. Due to the low intermolecular forces between fluorine and carbon chains, polytetrafluoroethylene has non viscosity. Polytetrafluoroethylene maintains excellent mechanical properties in a wide temperature range of -196 to 260 ℃, and one of the characteristics of perfluorocarbon polymers is that they remain brittle at low temperatures. Chemical corrosion resistance and weather resistance. Except for molten alkali metals, polytetrafluoroethylene is almost not corroded by any chemical reagents. For example, in concentrated sulfuric acid, nitric acid, hydrochloric acid, and even boiling in aqua regia, its weight and properties remain unchanged, and it is almost insoluble in all solvents, only slightly soluble in total alkanes (about 0.1g/100g) above 300 ℃. Polytetrafluoroethylene is non hygroscopic, non flammable, and stable to oxygen and ultraviolet rays, thus possessing excellent weather resistance.

Electrical performance

Polytetrafluoroethylene has low dielectric constant and loss over a wide frequency range, and has high breakdown voltage, volume resistivity, and arc resistance. The physical properties of polytetrafluoroethylene are relatively soft. Has very low surface energy.

Radiation resistance performance

The radiation resistance of polytetrafluoroethylene is poor (104 rad), and it undergoes degradation after being exposed to high-energy radiation, resulting in a significant decrease in the electrical and mechanical properties of the polymer. Polytetrafluoroethylene is generated by free radical polymerization of tetrafluoroethylene. Industrial polymerization reactions are carried out by stirring in the presence of a large amount of water to disperse reaction heat and facilitate temperature control. Polymerization is generally carried out at 40-80 ℃ and a pressure of 3-26 kgf/cm2. Inorganic persulfates and organic peroxides can be used as initiators, or redox initiator systems can be used. Each mole of tetrafluoroethylene releases 171.38 kJ of heat during polymerization. Dispersive polymerization requires the addition of perfluorinated surfactants, such as perfluorooctanoic acid or its salts.