Teflon used in cookware was already common in the market.
It is known for its non-stick properties which when you frying an egg, the egg can easily slide on the pan surface.
Do you know why Teflon was applied in cookware and what is the story behind the Teflon?
Below I will talk about the history and physics properties of the Teflon.
Why Teflon Is Used In Cookware
Teflon is a brand name for polytetrafluoroethylene (PTFE) and invented accidentally by Roy Plunkett of Dupont company. The first PTFE non-stick cookware was invented by French engineer Marc Grigo, patented in French and Tefal company was founded to produce non-stick pans. Teflon is used in cookware due to its high melting point, chemically inert, and slippery characteristic. The strong covalent bond of carbon-fluorine atoms and high electronegativity of fluorine atoms cause the PTFE molecules not easily disrupted by other substances. The compact stacking structure of the PTFE molecules makes it a high melting point material.
The story of Teflon
Teflon is a brand name for a synthetic material called polytetrafluoroethylene or PTFE.
It is used to coat the surface of the cookware for adding non-stick properties.
PTFE was invented by Roy Plunkett accidentally in 1938 while working for the Dupont company.
The synthetic material was found with unique properties, one of them is low coefficient of friction, and another one is good corrosion-resistance.
In the beginning, the PTFE was applied at atomic bomb of world war II, considered as military secret.
Until 1945, Dupont registered the Teflon trademark, a brand name for PTFE.
In 1954, a French engineer Marc Grigo invented the first cooking pan coated with PTFE, by his wife(Colette Grégoire )’s suggestion.
The process was patented in French and a company named Tefal formed to manufacture non-stick pans.
In 1961, Marion A. Trozzolo introduced the first non-stick pan in the US after using the PTFE on scientific tools and found its usefulness.
Since then the non-stick cookwares have started to spread across the world.
What is Teflon (PTFE)?
PTFE stands for polytetrafluoroethylene, a fluorocarbon solid, a polymer that consists of carbon and fluorine atoms,
Meaning a long chain of repeating units of carbon and fluorine atoms strung together.
A long PTFE polymer chain with carbon atoms as a backbone.
Each carbon atom is bonded to two fluorine atoms.
Why was Teflon used in cookware?
There are three reasons Teflon (PTFE) was applied in cookware.
Teflon (PTFE) is chemically inert.
The material that is used to make cookware must be chemically inert in nature.
This is to avoid the cookware materials having reactions with the food which get in touch, subsequently causing poison to the body.
The bond between the carbon and the fluorine is incredibly strong, this has made the PTFE chemically inner.
When the food is heated on the top surface of a Teflon pan, the PTFE molecules won’t react with food molecules to form new bonds.
There is no way any substance gets a chance to replace fluorine atoms to form new chemical bonding.
Teflon (PTFE) has a high melting point.
Cookware material is required with a high melting point for cooking(heating) purposes.
If the coating on the cookware surface is melted when cooking, the melted material will contaminate the food and become poisonous.
Teflon (PTFE) has a high melting point of 327 celsius, it begins to deteriorate when reaching 260 celsius.
What makes Teflon (PTFE) a high melting point?
The high melting point of Teflon (PTFE) can be related with its molecular structure and how the molecules pack together.
As I mentioned above, the PTFE is a polymer chain that is formed of a lot of fluorine-carbon molecules as repeating units.
A PTFE chain has carbon atoms as backbone, each carbon atom attached to two fluorine atoms.
The fluorine atoms surrounded the carbon atoms and spiraled around the long chain.
The repulsion force of the fluorine atom with its adjacent fluorine atom made the PTFE molecules look like a rod shape, with the fluorines arranged into spirals.
Fluorine atoms with helical arrangement around the carbon atoms backbone.
The rod shape PTFE molecules are like long pencils well stacked inside a box, neatly and compacted.
So how does this cause PTFE with a high melting point?
When PTFE molecules are better stacked, which provides a tighter fit with fewer spaces, surface area contact between molecules increases as well.
Tightly stacked molecules will maximize Van der Waals forces to cause high melting temperature points of PTFE.
Teflon (PTFE) is slippery (non-stick properties).
The Teflon pan is popular in the cookware market because of the non-stick properties.
Because of the non-stick pan, you don’t need to add too much oil for frying the egg, and flip the egg easily.
After the egg is done frying on the Teflon pan, you can easily slip the egg into the serving plate.
Because the foods are not sticking to the Teflon pan when cooking, you can easily clean the pan without spending much effort.
Even a Gecko can’t stick on a Teflon surface.
Why is Teflon so slippery?
This is because of fluorine atoms.
Fluorine is a highly electronegative atom meaning it strongly attracts electrons of a chemical bond towards itself.
Fluorine has a high electronegativity, meaning it repels other atoms.
The fluorine atoms surrounded carbon atoms like forming a chemical armor protecting the carbon atoms.
The fluorine atoms prevent the carbon atoms from reacting with other atoms or molecules.
This results in a slippery Teflon (PTFE) material.
The carbon and fluorine interacting so strongly and the intermolecular forces that make substances stick together don’t ever stand a chance.
Substances like frying eggs can’t form chemical bonds with Teflon molecules and slip on the pan freely.
Safety of Teflon (PTFE)
Cookware is something used to prepare the food.
Therefore safety is the main concern of choosing a material for the cookware.
Over the past decades, Teflon (PTFE) has been under investigation for its safety.
Teflon (PTFE) is chemically inert, when the flakes of Teflon enter into the body, Teflon molecules won’t react with atoms inside the body and will pass through to outside.
The concern is when Teflon (PTFE) is heated until 260 celsius, it may start to break down and release toxic fumes into the air, and cause flu-like symptoms when inhaled.
Some studies show the overheated Teflon may cause lung damage.
Previously Teflon was manufactured with PFOA (perfluorooctanoic acid).
PFOA is associated with kidney and liver diseases.
In 2006 US Environmental Protection Agency (EPA) launched a stewardship program to phase out the PFOA in the Teflon manufacturing process.
The program involved 8 leading companies of PFOA companies, including Dupont (developer of Teflon).
After 2013, all Teflon products were free of PFOA.
How to use Teflon cookwares safely.
Avoid using Teflon cookware with high temperature or more than 260 degree celsius. Recommend to set stove temperature to low or medium.
Do not preheat Teflon cookware before putting oil and foods on it. Empty cookware temperature will rise quickly when heated without any food on it.
Ensure good ventilation in the kitchen to free you from toxic fumes in your house. The examples could be to open up the kitchen window or install a ventilation fan near the cooking stove.
Stop using metal utensils on the Teflon cookware as this will scratch the non-stick surface and cause damage.
When washing the Teflon cookware, avoid using sharp cleaning tools like metal scrubbers. Suggest using a soft sponge to clean the cookware.
Replace the Teflon cookware if it is seriously damaged to prevent too much non-stick material flakes going into the cooked foods.