Tel:+86-511-88530583

Categories

Home > News > Content

PTFE Sheet Pyrolysis At High Temperature

Yangzhong Tianyou Seals Co.,Ltd | Updated: Oct 23, 2017

PTFE Sheet Pyrolysis at high temperature

More than a million, usually millions (polymerization degree in the order of 104, while the polyethylene only in 103). Generally, the crystallinity is 90 to 95% and the melting temperature is 327 to 342 ° C. The CF2 units in the polytetrafluoroethylene are arranged in a zigzag shape. Since the radius of the fluorine atom is slightly larger than that of the hydrogen, the adjacent CF2 units can not be completely cross-oriented, but form a helical twisted chain with almost fluorine atoms The entire surface of the polymer chain. This molecular structure explains the various properties of polytetrafluoroethylene. When the temperature is below 19 ° C, a 13/6 helix is formed; a phase change occurs at 19 ° C and the molecule is slightly unfastened to form a 15/7 helix. Although the carbon-carbon bonds and carbon-fluorine bonds in the perfluorocarbons need to absorb energy 346.94 and 484.88kJ / mol, respectively, but the decomposition of polytetrafluoroethylene to produce 1mol tetrafluoroethylene only energy 171.38kJ. So in the pyrolysis, the main depolymerization of polytetrafluoroethylene tetrafluoroethylene. The weight loss rate (%) of polytetrafluoroethylene at 260, 370 and 420 ° C is 1 × 10-4, 4 × 10-3 and 9 × 10-2, respectively. It can be seen that polytetrafluoroethylene can be used at 260 ℃ for a long time. Due to high temperature cracking also produce highly toxic by-product of fluorine-phosgene and perfluoroisobutylene, etc., so pay special attention to safety protection and to prevent Teflon exposure to open flame. Teflon plate appearance standard

(1) Teflon plate color for the resin color.

(2) should be uniform texture, the appearance of flat, do not allow cracks, bubbles, stratification, mechanical damage, knife marks and other defects.

(3) to allow a slight cloud-like elastic phenomenon.

(4) Permissible to have a diameter of 0.1 to 0.5 mm in the area of 10 × 10 cm, and no more than one non-metallic impurity having a diameter of 0.5 to 2 mm.

(5) density of 2.1-2.3T / m3.

Teflon plate (also known as PTFE plate, Teflon board, Teflon board) sub-molding and turning two, molding plate is made of PTFE resin at room temperature with molding method, and then sintering, Cooled and made. Polytetrafluoroethylene turning board from the polytetrafluoroethylene resin by the compact, sintered, peeling. Its products are widely used, with a very superior comprehensive performance: high and low temperature (-192 ℃ -260 ℃), corrosion (strong acid, alkali, aqua regia, etc.), weather resistance, high insulation, high lubrication, Non-toxic and other excellent features. Teflon plate (also known as PTFE plate, Teflon board, Teflon board) sub-molding and turning two, molding plate is made of PTFE resin at room temperature with molding method, and then sintering, Cooled and made. Polytetrafluoroethylene turning board from the polytetrafluoroethylene resin by the compact, sintered, peeling. Its products are widely used, with a very superior comprehensive performance: high and low temperature (-192 ℃ -260 ℃), corrosion (strong acid, alkali, aqua regia, etc.), weather resistance, high insulation, high lubrication, Non-toxic and other excellent features. Polytetrafluoroethylene (Teflon), "Teflon", "Teflon", "Teflon", "Teflon", "Teflon", "Teflon", "Teflon" , "Te Fulong", "Teflon" and so on.

It is made of polytetrafluoroethylene polymer compound, its structure is simple - [- CF2-CF2-] n-, with excellent chemical stability, corrosion resistance (PTFE referred to as PTFE or F4 , Is one of the world's most resistant to corrosion of the material, "plastic king" is commonly known as polytetrafluoroethylene, it is a kind of corrosion resistance of the best plastic. It is not known as acid, alkali, salt, Corrosion, that is, the most powerful aqua regia also helpless to it, hence the name of the plastic king, in addition to molten metal sodium and liquid fluoride, the ability of all other chemicals, widely used in various needs of acid and alkali and organic solvents, , High lubricity non-stick, electrical insulation and good anti-aging endurance, excellent temperature (can be at + 250 ℃ to -180 ℃ temperature long-term work.) PTFE itself is not toxic to people, but in the production One of the ingredients used in the process of perfluorooctanoate (PFOA) is thought to be carcinogenic.