HomeNews Introducing polytetrafluoroethylene (PTFE)

Introducing polytetrafluoroethylene (PTFE)

2020-08-04
Polytetrafluoroethylene (Poly tetra fluoroethylene, abbreviated as PTFE), commonly known as "Plastic King", is a polymer prepared by polymerizing tetrafluoroethylene as a monomer. White waxy, translucent, excellent heat and cold resistance, and can be used for a long time at -180~260ºC. This material is resistant to acids, alkalis, and various organic solvents, and is almost insoluble in all solvents. At the same time, PTFE has the characteristics of high temperature resistance, its friction coefficient is very low, so it can be used as a lubricating effect, and it has also become an ideal coating for easy cleaning of the inner layer of water pipes; it is toxic and carcinogenic to the human body.

According to the list of carcinogens of the International Agency for Research on Cancer of the World Health Organization, polytetrafluoroethylene is classified as three types of carcinogens, that is, it is not clear about its carcinogenic effects on humans.


Property data editing
1. Properties: There are three types of granular, powder and dispersion. It is transparent when it is neutral, and the thickness increases to become off-white
2. Density (g/mL, 25ºC): 2.1~2.3
3. Relative vapor density (g/mL, air=1): not determined
4. Melting point (ºC): 327
5. Boiling point (ºC, normal pressure): 400
6. Boiling point (ºC, 5.2kPa): not determined
7. Refractive index: 1.37 (20ºC)
8. Solubility: insoluble in any solvent

Nature and stabilityedit
1. Stable under normal temperature and pressure, avoid humidity, heat and high temperature
There is no real melting point, and it decomposes slowly above 450℃ and becomes a gas directly. At 327°C, the mechanical strength suddenly disappeared. Insoluble in any solvents. In addition to reacting with molten alkali metals, it is not corroded by any substance, even if it is boiled in hydrofluoric acid, aqua regia or fuming sulfuric acid, sodium hydroxide, it will not change.
2. White, odorless, tasteless, non-toxic powder, commonly known as "Plastic King". It has excellent chemical stability, corrosion resistance, airtightness, high lubrication and non-stickiness, electrical insulation and good anti-aging resistance. High temperature resistance, the working temperature can reach 250℃. It is resistant to low temperature and has good mechanical toughness at low temperature. Even if the temperature drops to -196℃, it can maintain 5% elongation. Corrosion resistant, inert to most chemicals and solvents, resistant to strong acids and alkalis, water and various organic solvents. Good weather resistance and the best aging life among plastics. High lubrication is the lowest friction coefficient among solid materials. Non-sticking is the one with the smallest surface tension among solid materials and does not stick to any substance. It is non-toxic, physiologically inert, and has no adverse reactions as artificial blood vessels and organs implanted in the body for a long time.

Synthesis methodedit
Industrial production adopts suspension polymerization or emulsion polymerization.
1. Preparation of monomer tetrafluoroethylene
Industrially, trichloromethane is used as raw material, and trichloromethane is fluorinated with anhydrous hydrofluoric acid. The reaction temperature is above 65ºC. Antimony pentachloride is used as a catalyst. Finally, tetrafluoroethylene is made by thermal cracking. Zinc can also be used with tetrafluorodichloroethane at high temperature to produce tetrafluoroethylene.
2. Preparation of polytetrafluoroethylene
In an enamel or stainless steel polymerization kettle, use water as the medium, potassium persulfate as the initiator, perfluorocarboxylic ammonium salt as the dispersant, fluorocarbon as the stabilizer, and tetrafluoroethylene through redox polymerization to produce polytetrafluoroethylene Vinyl.
Add various additives into the reaction kettle, the tetrafluoroethylene monomer enters the polymerization kettle in the gas phase, adjust the temperature in the kettle to 25°C, and then add a certain amount of activator (sodium bisulfite) to initiate polymerization through an oxidation-reduction system. Continuously add monomers during the polymerization process and keep the polymerization pressure 0.49~0.78MPa. The dispersion obtained after polymerization is diluted with water to a certain concentration, and the temperature is adjusted to 15~20ºC. After condensing with mechanical stirring, it is washed and dried with water. This product is a fine granular resin.


Ecological data editing
This substance may be harmful to the environment, so special attention should be paid to water bodies.


Application editor
1. Used in the electrical industry, used in the aerospace, aviation, electronics, instrumentation, computer and Other industries as the insulation layer of power and signal lines, corrosion-resistant and wear-resistant materials can be used to make films, tube sheets, bearings, washers, valves and Chemical pipelines, pipe fittings, equipment container linings, etc.
2. It can be used to replace quartz glassware in the fields of electrical appliances, chemical industry, aviation, machinery and other fields. It can be used for ultra-pure chemical analysis and storage of various acids, alkalis and organic solvents in atomic energy, medicine, semiconductor and other industries. High-frequency wire and cable sheathing, corrosion-resistant chemical utensils, high-cold oil pipelines, artificial organs, etc. can be used as additives for plastics, rubber, coatings, inks, lubricants, greases, etc.
Teflon bottle
3. This product is resistant to high temperature and corrosion, has excellent electrical insulation, aging resistance, low water absorption, and excellent self-lubricating performance. It is a universal lubricating powder suitable for various media and can be quickly applied to form a dry film , To be used as a substitute for graphite, molybdenum and other inorganic lubricants. It is a mold release agent suitable for thermoplastic and thermosetting polymers with excellent bearing capacity. It is widely used in the elastomer and rubber industry and anti-corrosion.
4. Used as a filler for epoxy resin to improve the wear resistance, heat resistance and corrosion resistance of epoxy adhesives.
5. Mainly used as a binder and filler for powder cakes.

Yoki

Ms. Yoki

SEND INQUIRY

Home

Product

Phone

About Us

Inquiry

We will contact you immediately

Fill in more information so that we can get in touch with you faster

Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.

Send