Production technology of PTFE polymer

Polytetrafluoroethylene (PTFE) is a polymer with unique properties, widely used in various fields due to its excellent heat resistance, chemical resistance, electrical insulation, and low coefficient of friction. The production technology of PTFE mainly includes the following steps:

Monomer Synthesis: PTFE is polymerized from tetrafluoroethylene (TFE) monomers. The synthesis of TFE monomers is usually obtained through the electrolysis reaction of hydrofluoric acid and ethylene.

Polymerization Reaction: During the polymerization process, TFE monomers undergo polymerization reactions under certain temperatures and pressures with the addition of catalysts to form high molecular weight PTFE. This process is carried out in an aqueous phase, typically using suspension polymerization or emulsion polymerization methods.

Post-treatment: After polymerization, PTFE needs to be post-treated, which includes washing, drying, crushing, and screening steps to remove residual catalysts and solvents, resulting in pure PTFE resin particles.

Molding and Processing: PTFE resin particles can be molded and processed in various ways, including:

• Compression Molding: PTFE powder is placed into molds and shaped through high temperature and pressure.
• Ram Extrusion: PTFE powder is pushed through molds by a ram, commonly used for manufacturing tubes and rods.
• Hot Pressing: PTFE is shaped under isostatically applied pressure and heat, suitable for manufacturing complex shapes or thin-walled parts.
• Resin Casting: Liquid PTFE resin is poured into molds and shaped through heat curing, suitable for manufacturing complex shapes or high-precision products.

Sintering: The sintering process of PTFE significantly affects the final properties of the product, including density, hardness, permeability, and mechanical properties. The sintering temperature, time, and pressure all need to be precisely controlled.

Chemical Composite Plating: A metal coating can be formed on the surface of PTFE through chemical composite plating methods to enhance its wear resistance and corrosion resistance.

Supercritical Carbon Dioxide Assisted Extrusion: The use of supercritical carbon dioxide to swell PTFE reduces its molding temperature, enabling efficient extrusion molding.

The production technology of PTFE is continuously evolving to meet the demands of various application fields, including chemical engineering, electronics, medical, and aerospace. With technological advancements, the production efficiency and product quality of PTFE are also continuously improving.