If Teflon doesn't stick to anything or nothing sticks to Teflon, how does Teflon stick to the pan?
Arvind, part of the process seems to be a trade secret. Here it says:
'Nonstick cookware
7 One of the most common and visible uses of PTFE is coating for nonstick pots and pans. The pan must be made of aluminum or an aluminum alloy. The pan surface has to be specially prepared to receive the PTFE. First, the pan is washed with detergent and rinsed with water, to remove all grease. Then the pan is dipped in a warm bath of hydrochloric acid in a process called etching. Etching roughens the surface of the metal. Then the pan is rinsed with water and dipped again in nitric acid. Finally it is washed again with deionized water and thoroughly dried.
8 Now the pan is ready for coating with PTFE dispersion. The liquid coating may be sprayed or rolled on. The coating is usually applied in several layers, and may begin with a primer. The exact makeup of the primer is a proprietary secret held by the manufacturers. After the primer is applied, the pan is dried for a few minutes, usually in a convection oven. Then the next two layers are applied, without a drying period in between. After all the coating is applied, the pan is dried in an oven and then sintered. Sintering is the slow heating that is also used to finish the billet. So typically, the oven has two zones. In the first zone, the pan is heated slowly to a temperature that will evaporate the water in the coating. After the water has evaporated, the pan moves into a hotter zone, which sinters the pan at around 800°F (425°C) for about five minutes. This gels the PTFE. Then the pan is allowed to cool. After cooling, it is ready for any final assembly steps, and packaging and shipping.'
Read more: http://www.madehow.com/Volume-7/Teflon.html#ixzz3dHm3I2VL'
Dear all;
In addition to what Dr. Michael Brückner said, the PTFE is not used as a virgin coat, it is rather used in a formulation (compound) of mainy additives among which adhesion promoters and heat stabilizers. PTFE is the matrix that holds all ingredients together. Regards
- Badges
- Science topic
- Similar topics
- Chemistry