PTFE rubber sheet

PTFE rubber sheets can be formed by compression or extrusion processing; It can also be made into aqueous dispersions for coating, impregnation, or fiber production. Polytetrafluoroethylene is widely used in industries such as atomic energy, aerospace, electronics, electrical engineering, chemical engineering, machinery, instruments, meters, construction, textiles, and food as a high and low temperature resistant, corrosion-resistant (based on actual reports) material, insulation material, and anti stick coating.

Atmospheric aging resistance: radiation resistance and low permeability: long-term exposure to the atmosphere, the surface and properties remain unchanged.

Non flammability: The oxygen limit index is below 90.

Good acidity and alkalinity: insoluble in strong acids, strong bases, and organic solvents (based on actual reports).

Oxidation resistance: able to withstand corrosion from strong oxidants.

Acidity and alkalinity: neutral.

The mechanical properties of polytetrafluoroethylene are relatively soft. Has very low surface energy.

Performance Table of Polytetrafluoroethylene:

Name Unit Indicator

Density kg m3 2.10-2.30 × 103

Linear expansion coefficient (perpendicular to the direction of pressure) 1 ℃ 20-60 ℃ 10.3 × 10-5

20～100℃10.5×10-5

20～150℃11.4×10-5

20～200℃12.8×10-5

Thermal conductivity Wm. K 0.256

Poisson's ratio (25 ℃) 0.40

Refractive index% 1.37

Water absorption rate

Contact angle with water 114 ° -115 °

Surface swelling force NCm 18.5 × 10-5

(3) The difficulty in molding and secondary processing is due to the very high melt viscosity of polytetrafluoroethylene, which can reach 380 ℃ and cannot be used with plastic Commonly used processing techniques such as injection molding and rolling molding are used for molding. Meanwhile, PTFE has a relatively high molding shrinkage rate, with a molding shrinkage rate of 1% to 5%.

(4) PTFE with poor creep resistance undergoes significant creep and is prone to cold flow under long-term load. The cold flow phenomenon of PTFE is currently one of the main reasons limiting its widespread application.

(5) PTFE has poor performance, low hardness, and high wear. When the load (P) and sliding speed (V) exceed certain conditions, its wear will become very large. Therefore, there is a definite limit to the PV value in application. For example, when used as a bearing, the PV value should not exceed

(6) Poor thermal conductivity can only cause thermal expansion, thermal fatigue, and thermal deformation.

(7) Poor adhesion with other materials. The surface energy of PTFE is relatively low, which is not conducive to bonding and is not suitable for printing, dyeing, painting, etc.