Why Do We Use Fluoroplastics?

The performance characteristics of fluoroplastics: polytetrafluoroethylene and perfluoro (ethylene-propylene) copolymer (FEP) are completely composed of carbon atoms and fluorine atoms, while polyvinylidene fluoride (PVDF) and polyvinyl fluoride (PVF) molecules It also contains hydrogen atoms, and polychlorotrifluoroethylene also contains chlorine atoms. The excellent performance of fluoroplastics is achieved by the high binding energy between carbon atoms and fluorine atoms. The main chain skeleton of PTFE is carbon atoms, and the surrounding is completely surrounded by fluorine atoms, so its various properties are high, while PFA, FEP, ETFE, and other varieties have a low softening point due to the influence of side groups, and other properties There are also changes.

1. Thermal properties Fluoroplastics have flame retardancy and excellent heat resistance. The continuous use temperature of PTFE and PFA can reach 260℃, and it can be used at 300℃ for a short time. The use temperature of FEP is 60℃ lower than them. The higher PCTFE can be used at 120℃. Fluorine plastics, such as long-term use at high temperatures, will cause changes in crystallinity, so special attention must be paid when manufacturing equipment lining.

2. Chemical resistance Fluoroplastics have excellent chemical resistance and solvent resistance, especially PTFE, PFA, FEP, etc., which are not corroded by acids, alkalis, and solvents. But molten alkali metals, fluorine, and trifluorochlorinated hydrocarbons have varying degrees of influence on them. PCTFE, ETFE, PVDF, etc. are slightly less resistant to chemicals in fluoroplastics, but they have much better corrosion resistance than other plastics.

3. Electrical properties The electrical properties of fluoroplastics, especially high-frequency electrical properties, are hard to match with other materials. The molecules of PTFE, FEP, and PFA have very low polarity, small changes in a wide temperature and frequency range, stable relative dielectric constant, low dielectric loss, and excellent electrical insulation. Among them, PVDF also has specific piezoelectricity and pyroelectricity, which can be used to make piezoelectric materials.

4. Mechanical properties of fluoroplastics molecules increase in hydrogen and chlorine atoms, and their tensile strength will also increase. The embrittlement temperature of PTFE and PCTFE is extremely low, showing excellent low-temperature performance. PTFE has a low friction coefficient and a specific self Lubricity, but PTFE has its own shortcomings such as large wear and cold flow. Various fillers can be used to improve wear resistance and overcome cold flow.

5. Non-stickiness Fluoroplastics have specific non-stickiness. In particular, molecules such as PTPE, FEP, and PFA have high fluorine content, and the surface contact angle is very large, making the liquid on the surface of the fluoroplastic product spherical. It is not easy to bond with resin, so it is often used to make a non-sticky layer on the surface of the cookware.

6. Weather resistance All kinds of fluoroplastics have excellent weather resistance, and their various properties remain unchanged even if exposed to harsh temperatures for a long time.

7. Hydrophobicity Fluoroplastics have low water absorption, especially PTFE. Its hydrophobicity can be used to manufacture breathable and impermeable composite fabrics and other equipment.