PTFE tube manufacturers analyze the various properties of PTFE, PTFE products are widely used in telecommunications, computers, testing and measurement, national defense, aviation and aerospace markets and many other high-performance, high-challenge areas.

Polytetrafluoroethylene products are used as medical materials. Due to the excellent mechanical properties, durability, stability and biological adaptability of expanded polytetrafluoroethylene materials, it will not cause rejection of the body, has no physiological side effects on the human body, and has the characteristics of microporous structure. Since the 1970 s, it has been first made into artificial blood vessels for clinical use. Now, due to its excellent performance, PTFE is more and more widely used in medicine. These include artificial blood vessels and patches for soft tissue regeneration and surgical sutures for vascular, cardiac, general and plastic surgery. For example, the more common cosmetic surgery rhinoplasty and plastic jaw is the use of polytetrafluoroethylene as a filler material. Used as an anti-sticking material PTFE material has the smallest surface tension in 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 a coating for tableware. The anti-sticking lining is mainly used for non-stick pans and microwave ovens.

1. When the temperature is lower than 19 ℃, a 13/6 helix is formed; a phase transition occurs at 19 ℃, and the molecules are slightly unwound to form a 15/7 helix.

2. Mechanical properties: Its coefficient of friction is extremely small, only 1/5 of polyethylene, which is an important feature of perfluorocarbon surface. Since the fluorine-carbon chain intermolecular force is extremely low, polytetrafluoroethylene has non-tackiness.

3. PTFE electrical properties: PTFE in a wide frequency range of dielectric constant and dielectric loss are very low, and the breakdown voltage, volume resistivity and arc resistance are high.

4. Radiation resistance: The radiation resistance of PTFE is poor (104 rad), which causes degradation after high-energy radiation, and the electrical and mechanical properties of the polymer are significantly reduced. Polymerization: Polytetrafluoroethylene is produced by radical polymerization of tetrafluoroethylene.

Industrial polymerization is carried out with stirring in the presence of a large amount of water to disperse the heat of reaction and to facilitate temperature control. The polymerization is generally carried out at a temperature of 40 to 80 ° C. under a pressure of 3 to 26 kgf/cm2, and inorganic persulfates, organic peroxides or redox initiation systems can be used as initiators. The exotherm was 171.38kJ per mole of tetrafluoroethylene polymerized. The dispersion polymerization requires the addition of a perfluoro surfactant, such as perfluorooctanoic acid or its salts, with an expansion coefficient (25-250 ° C.) of 10-12 × 10-5/°C.

1. PTFE maintains excellent mechanical properties in a wide temperature range of -196~260 ℃. One of the characteristics of perfluorocarbon polymers is that they are not brittle at low temperatures.

2. The relative molecular mass of PTFE is relatively large, ranging from hundreds of thousands to over 10 million, generally to millions (the degree of polymerization is on the order of 104, while polyethylene is only 103). Generally, the crystallinity is 90 ~ 95% and the melting temperature is 327~342 ℃.

3. The CF2 units in the polytetrafluoroethylene molecule are arranged in a sawtooth shape. Since the radius of fluorine atoms is slightly larger than that of hydrogen, the adjacent CF2 units cannot be completely oriented in trans, but form a spiral twisted chain. The fluorine atoms almost cover the surface of the entire polymer chain.

4. Adding any filler to PTFE that can withstand the sintering temperature of PTFE, its mechanical properties can be greatly improved, while maintaining other excellent properties of PTFE. Filled varieties are glass fiber, metal, metal oxide, graphite, molybdenum disulfide, carbon fiber, polyimide, EKONOL?, wear resistance, limit PV value can be increased by 1000 times.

5. Teflon cloth PTFE pipe selection of suspension polymerization PTFE resin by plunger extrusion processing. Polytetrafluoroethylene can be molded by compression or extrusion; it can also be made into an aqueous dispersion for coating, impregnation or fiber. It is generally used in corrosion-resistant pipes, containers, pumps, valves, radar, high-frequency communication equipment, radio equipment and so on.

Polytetrafluoroethylene has the best chemical resistance and dielectric properties among known plastics. PTFE braided packing is the 1 kind of good dynamic sealing material. Teflon? film is suitable for capacitor dielectric,? special cable insulation, wire insulation, electrical instrument insulation and sealing gasket, but also do non-stick tape, sealing tape, demoulding it is made of expanded polytetrachloroethylene tape woven.