Commodity name "Teflon", "Teflon", "Teflon", "F4" and other melting point: 327℃ density: 2.17g /cm3 Advantages: high temperature resistance - the use of working temperature up to 250℃. Low temperature resistance -- good mechanical toughness; Even if the temperature drops to -196℃, 5% elongation can be maintained. Corrosion resistance - For most chemicals and solvents, showing inertia, strong acid and alkali resistance, water and various organic solvents. Weather resistant - has the best aging life of plastics. High lubrication - is the lowest friction coefficient of solid materials (0.01~0.10). Non-adhesion - is the smallest surface tension in solid materials, does not adhere to any substance. Non-toxic -- with physiological inertia, as artificial blood vessels and organs implanted in the body for a long time without adverse reaction. Electrical insulation - can resist 1500 volts of high voltage. Disadvantages: cold flow, non-stick, high coefficient of linear expansion (20 times of steel)