PTFE membrane

Product name: PTFE film/PTFE film/PTFE directional film

Material: PTFE

Product size, specifications, thickness can be customized according to demand

Color: multiple colors are available

Product features:

Wide temperature range, flame retardant, high temperature resistance

Smooth surface does not adhere, good self cleaning

Long service life, can prevent chemical corrosion and ultraviolet erosion, not easy to aging

Dielectric property is not conductive and can resist high voltage

Application scope:

Mainly used in chemical industry, iron and steel, metallurgy, carbon black, power generation, pharmaceutical, biochemical, microelectronics and laboratory supplies

PTFE film size:

Molecular structure characteristic

The excellent properties of PTFE are determined by its molecular structure. The polytetrafluoroethylene molecule consists of two elements, C and F covalently bonded, and the C-F bond has a higher bond energy. Therefore, ptfe has a high degree of stability, not easy to chemical reaction.

Although both PTFE and PE are linear polymers, and the chain skeleton consists of carbon atoms, fluorine and oxygen atoms play different roles around carbon atoms. The van der Waals radius of fluorine atom is 0.136nm, which is obviously larger than that of hydrogen atom 0.11~0.12nm. Compared with polyethylene, there is a stronger repulsion between the unchained atoms in PTFE, making it larger. Due to the larger van der Waals radius of fluorine atoms, the larger repulsion between fluorine atoms makes the ptfe polymer chain more resistant to rotation than polyethylene, so the flexibility of the PTFE chain can be expected. It is less flexible than a polyethylene chain. This gives ptfe a high melting point and high melt viscosity.

2. Chemical stability

The two fluorine atoms connected by each carbon atom in PTFE are symmetrical in space structure. The nonpolar CF bond of the whole molecule has high and stable bond energy. This molecule is helical. The CC backbone is completely shielded by the F atom. Therefore, ptfe has good chemical stability, water and various organic solvents can not dissolve or expand. Strong acid, strong base and strong oxidant will not affect PTFE even at high temperature, and its chemical resistance even exceeds some precious metals. Only the element F itself with the molten alkali metal or its complex can affect it. It erodes.

3. Thermal performance

Polytetrafluoroethylene has excellent high temperature and low temperature resistance. Its melting point is 327℃ and decomposition temperature is 415℃. It can be used in the range of 200~260℃ for a long time. However, the main disadvantage of PTFE is that it will not change from a highly elastic state to a viscous fluid state above the melting point when it does not flow, even when heated to decomposition temperature, which makes it impossible to use universal thermoplastic material molding methods.

4. Mechanical properties

Because the polytetrafluoroethylene molecular chain is non-polar, the attraction between macromolecules is small. Because the macromolecular chain has no branches, strong rigidity and less entanglement, the macromechanical properties of PTFE are not good. But ptfe has good ductility and ductility when the crystallinity is low. In addition, PTFE has excellent fatigue resistance. Even after the material is damaged, the material retains its physical integrity without breaking.

5. Electrical performance

In the polytetrafluoroethylene macromolecular chain, the fluorine atoms are symmetrical and evenly distributed, so the molecule is non-polar, which makes it have excellent dielectric properties. The dielectric properties are almost unaffected by the electric field frequency and remain constant over a wide temperature range. In addition, the presence of voids in PTFE also reduces the corona resistance of the material.

6. Surface properties

PTFE is not easy to be wet by ordinary liquid, its critical surface tension is 0.0185N/m, and the contact Angle with water is 108°. Therefore, PTFE is an excellent anti - stick material with excellent non - stickability. But on the other hand, this property makes it difficult to combine with other materials, limiting its applications.