Non-stick utensils, i.e., utensils with a powerful coating of Teflon, are a remarkable invention of mankind, especially for those people who spend a lot of time doing the dishes or cooking complicated meals with many pots and pans. Those who have no idea what Teflon is all about, rest assured, you’re in for a crash course!
Teflon… What Is It?
Teflon is actually the brand name of PTFE-based compounds made by DuPoint Co., an organization that is credited with the invention of the compound. However, what is PTFE?
PTFE is a synthetic polymer of tetrafluoroethylene; in simple terms, it’s a chemical compound. More specifically, it’s a fluorocarbon that only contains atoms of carbon and fluorine, which are bound together quite strongly. The compound has countless applications, especially because it is hydrophobic in nature, meaning that neither water nor other water-containing substances can ‘wet’ it or stick to it. This is the most important reason why PTFE is so commonly used in non-stick cookware, as it doesn’t let any outside substance bind to it easily. Imagine making scrambled eggs and having that crusty, impossible to remove mess in a normal frying pan. With PTFE, you don’t have any of those problems!
The question is, how does a material like this, which is so shy in terms of ‘gelling’ with other substances, manage to stick to those utensils in the first place to make them ‘non-stick’?
Sticking a Non-Sticky Material
As I said, Teflon is a shy and introverted material, so in order to help it get along with other materials, or at least the utensils that need a non-stick coating, you probably need external help. And that help will have to be rather impressive…
There are a few different methods that can be used to make Teflon stick to pans. The method used by DuPoint itself involves ‘sandblasting’ the pan to create an uneven surface, which is best suited for encouraging the adherence of teflon to the surface. If you don’t know what this is, sandblasting is a process through which very minute, uniform particles are propelled at a target at high speeds. It’s called ‘sandblasting’ because some years ago, sand was the most common material used for the purpose. Sandblasting is generally used to clean or make etchings on a material.
After the pan is sandblasted, a primer layer of Teflon is sprayed on before it is baked at a high temperature. This way, Teflon is secured in place in a nice and tight ‘mechanical grip’, basically like the way ice cubes get stuck in an ice tray. A few more rounds of spraying Teflon onto the surface is done before the object is finally deemed a ‘finished product’.
Another method involves heating Teflon to a very high temperature and pressing it firmly against the pan. Sounds pretty rudimentary, right?
Well, it actually isn’t. If you did heat Teflon to a high temperature and then press it hard enough against the desired pan, then it does, in fact, stick to the pan (referred to as ‘sintering’ in scientific circles). However, there is a caveat to this. As soon as the pan is brought back to normal room conditions, the layer of Teflon would peel away quite easily, and you would be back at square one.
Since you don’t want that to happen, before sticking it to the pan, Teflon is subjected to a onslaught of ions in a high vacuum under an electric field. This weakens the forces holding some of the fluorine atoms to carbon atoms, and consequently, some of the bonds holding fluorine atoms break. As a result, carbon atoms bind to other groups of atoms (like oxygen atoms) that stick firmly to the surface. After this is done, they carry out the process of sintering; therefore, the layer of Teflon that is formed adheres strongly to the pan.
Method#3: Using a Reducing Agent
There’s one final method, although it is quite similar to the one mentioned above. In this method, a reducing agent is used. Essentially, this is a compound that ‘reduces’ the bonds, or in other words, breaks the bonds between carbon and fluorine atoms, which allows fluorine atoms to bind to each other. Our beloved carbon atoms become free and begin desperately looking for some company. In effect, the free carbon, which turns into unsaturated hydrocarbons, becomes sticky enough to get the Teflon sheet to adhere to the pan.
Only after going through all these treatments and hardships does Teflon become ‘kind’ enough to impart that vital ‘non-stick’ property to utensils. Therefore, it’s only fair that we treat our non-stick utensils with the utmost care, and take a ‘soft’ touch (literally) when washing them after use.
- Scientific American
- How Teflon Sticks to Nonstick Pans – About education
- If Nothing Sticks To Teflon, how does it stick to the Pan? – PhysLink