Question

Teflon, a polymer of tetrafluoroethylene, is an excellent plastic material for films and coatings. Which of the following is not the property of Teflon?
A.It is unaltered by radiation
B.It can withstand high temperatures
C.It is one of the most chemically-resistant plastic in the world
D.It is an ideal insulator for high-frequency fittings

Answer 1

Polytetrafluoroethylene (PTFE) is a tetrafluoroethylene fluoropolymer that has a wide range of uses. Teflon by Chemours, a spin-off from DuPont, is the most well-known brand name for PTFE-based formulations. The chemical was first discovered in 1938 by DuPont. Because it is a high-molecular-weight polymer made entirely of carbon and fluorine, polytetrafluoroethylene is a fluorocarbon solid. As fluorocarbons exhibit reduced London dispersion forces due to their high electronegativity, PTFE is hydrophobic: neither water nor water-containing compounds wet it. The coefficient of friction of PTFE is one of the lowest of any substance.

Complete answer:
Non-stick coatings for pans and other kitchenware are made of polytetrafluoroethylene. Because of the strength of carbon–fluorine bonds, it is commonly employed in containers and pipes for reactive and corrosive chemicals because it is non-reactive. PTFE decreases friction, wear, and energy consumption of equipment when used as a lubricant. It's frequently used as a graft material in surgical procedures. It's also commonly used as a catheter coating, which prevents bacteria and other infectious agents from adhering to catheters and causing hospital-acquired illnesses.
At ambient temperature, PTFE is a white solid with a density of around $2200\text{ }kg{{m}^{-3}}$and a melting point of 600 K ($327\text{ }{}^\circ C;\text{ }620\text{ }{}^\circ F$). At temperatures as low as 5 K ($268.15\text{ }{}^\circ C;\text{ }450.67\text{ }{}^\circ F$), it retains excellent strength, hardness, and self-lubrication, while maintaining acceptable flexibility at temperatures over 194 K ($79\text{ }{}^\circ C;\text{ }110\text{ }{}^\circ F$). All fluorocarbons, including PTFE, get their characteristics from the combined action of carbon-fluorine bonds. Depolymerization of PTFE occurs at temperatures over $650700\text{ }{}^\circ C$ ($1,2001,290\text{ }{}^\circ F$).

Because PTFE (Poly tetra fluoro ethylene) is highly sensitive, it is not appropriate for applications requiring radiation exposure because it will deteriorate. Because PTFE degrades in high-radiation settings, it has never been renowned for its performance. However, in specific applications, it can obtain some advantageous material characteristics.

Hence option a is correct.

Note:
In the aerospace sector, PTFE film is frequently used in the manufacture of carbon fibre composites as well as fibreglass composites. When debulking (vacuum removal of air from between layers of laid-up plies of material) and curing the composite, generally in an autoclave, PTFE film is utilised as a barrier between the carbon or fibreglass component being constructed and the breather and bagging materials used to encapsulate the bonding. The PTFE layer prevents non-production materials from adhering to the component being produced, which is sticky because of the carbon-graphite or fibreglass plies being pre-pregnant with bismaleimide resin.