The monomer of PTFE is tetrafluoroethylene (TFE), and its boiling point is -76.3 degrees Celsius. It is extremely explosive in the presence of oxygen and can be comparable to gunpowder. Therefore, its production, storage and use in industry require very strict protection, the output also needs to be controlled, which is also one of the main sources of PTFE cost. TFE usually uses free radical suspension polymerization in the industry, using persulfate as an initiator, the reaction temperature can be between 10-110 degrees Celsius, this method can obtain very high molecular weight PTFE (even can be over 10 million), no apparent chain transfer occurs.
Since the melting point of PTFE is very high, which is close to the decomposition temperature, and its molecular mass is not small, it is almost impossible to achieve the ideal melt flow rate by simply relying on heating like ordinary thermoplastic polymers. How is the Teflon tape or Teflon tube made? In the case of molding, PTFE powder is generally poured into the mold, and then heated and pressurized to sinter the powder. If extrusion is required, hydrocarbon compounds need to be added to PTFE to help stirring and flowing. The amount of these hydrocarbon compounds must be controlled within a certain range, otherwise it is easy to cause excessive extrusion pressure or finished product defects. After the desired form, the hydrocarbon compounds are removed by slow heating, and then heated and sintered to form the final product.
Uses of PTFE
One of the main uses of PTFE is as a coating. From the small non-stick pan at home to the outer wall of the water cube, you can feel the magical effect of this coating. Other uses are sealing tape, wire outer protection, barrel inner layer, machine parts, labware, etc. If you need a material to be used in harsh conditions, then consider it, it may have unexpected results .
Post time: Aug-29-2022