Non-stick cookware

In 1998 it was also announced that PEEK had obtained FDA approval for food contact applications. This raises the possibility of the material being used for such purposes as food containers, bearings and seals for processing equipment and as a coating for metals in non-stick cookware. 

PTFE Aqueous 350 (662) Non-stick cookware, wire coating,... 

As well as atmospheric sources, pyrolysis of fluorine-containing polymers, which may occur in engine oil additives, non-stick cookware or incinerated medical equipment (i.e. syringes) and household waste, may also produce TFA. This process may also produce perfluorinated alkanes and cycloalkanes, which have significant GWP, and have estimated tropospheric half-lives of more than 2000 years. Trifluoroacetate may also be produced by metabolism of trifluoromethyl-containing drugs such as Prozac, and anaesthetics including halothane and iso-fluorane [4],... 

Polyphenylene sulfide release coatings are being used in non-stick cookware. In another application, tire molds are coated to aid the release of the finished tire from the mold (15). When this release coating was used, more than 8000 tires were produced without cleaning the mold, whereas cleaning was required after producing only 500-600 tires when a conventional silicone mold release agent was used. In addition the need for a blemish paint was eliminated, tire rejects were reduced, and an improved surface finish resulted. 

Non-stick cookware, water- and bacteria- repellent textiles, wire and cable covers, corrosion-resistant linings for pipes and valves, seals and gaskets, skis. 

Consumers know PTFE because it is used as a coating material in non-stick cookware. The excellent chemical resistance makes it suitable for coating reactors and piping that are exposed to aggressive chemicals. The extremely low coefficient of friction makes it usefiil for bearings and gears. Specialty bullets are coated with PTFE to reduce wear on a rifle barrel. 

Friction and surface energy (critical surface tension) are very low for fluoropolymers (Table 2.6). Both characteristics are at the root of many applications of these plasties, such as bridge expansion bearings (low friction) and non-sticking cookware (low surface energy). In this section, these properties are related to the intermolecular forces of fluoropolymers and other materials. To help the reader, definitions of the forces are briefly discussed. 

PPS is used as a coating material on non-stick cookware in competition with Teflon, and in corrosion resistant coatings for industrial parts. PPS fibre is used for manufacture of filter bags, braided sleevings and dryer belts, in competition with fibreglass. 

Electrical insulation at high temperature, gaskets, tubes, seals, non-stick cookware finishing, unlubricated gears. 

The highly crystalline fluoropolymers include fluorinated ethylene polyethylene, perfluoroalkoxyethylene, polychlorotrifluoroethylene and ethylene-tetrafluoroethylene co-polymer but PTFE is perhaps the most widely used and certainly best known as Teflon in non-stick cookware. 

When purchased by the consumer take-away foods may also have come into contact with other food contact materials. Examples include the packaging in which the food is stored prior to cooking/heating, the metal and/or plastic food contact utensils and the cookware (e.g. metal pans which may have a non-stick coating applied) used in the cooking/heating of the foodstuff at the point of sale. Migration from these materials and articles is not described here. 

DuPont registered the Teflon trademark in 1945 and released Its first Teflon products a year later. Since then the non-stick coating has become a household staple on kitchen cookware, in baking sprays, and as a stain repellantfor fabrics and textiles. 

Ruorine comes from the Latin wordfluere, which means to flow. The mineral fluorite, which contains fluorine and calcium, is used to lower the melting points of other minerals to make it easier to separate them from their ores. Fluorine compounds are added to toothpaste and drinking water to protect tooth enamel from decay. A compound of fluorine and carbon provides a non-stick coating for the cookware shown in Figure 7-20a. When fluorine reacts with isotopes of uranium, the gases that form are separated by differences in mass. This process is called uranium enrichment it provides the uranium-235 fuel for nuclear reactors. 

Q Cookware with a non-stick surface is easy to clean and can reduce the use of cooking oils and fats. A garden hose made from polyvinyl chloride is sturdy and flexible. 

MAJOR PRODUCT APPLICATIONS EMI/RFI shielding, powder coating, anti-size lubricants, decorative lacquers, waterborne coatings, conductive plastics, non-stick coatings, coatings for cookware, adhesives, inks, sealants... 

Ryton Polyphenylene Sulfide is a new commercial plastic which is characterized by good thermal stability, retention of mechanical properties at elevated temperatures, excellent chemical resistance, a high level of mechanical properties, and an affinity for a variety of fillers. It is produced from sodium sulfide and dichlorobenzene. Its unusual combination of properties suggests applications in a variety of molded parts such as non-lubricated bearings, seals, pistons, impellers, pump vanes, and electronic components. Tough coatings of polyphenylene sulfide can be applied to metals or ceramics by a variety of techniques and are used as protective, corrosion-resistant coatings in the chemical and petroleum industries. Incorporation of small amounts of polytetrafluoroethylene provides excellent non-stick properties in both cookware and industrial applications. 

PTFE (Teflon) Crystalline, corrosion resistance, very low friction, nonsticking. Coatings, cookware, bearings, gaskets, insulation tape, non-stick linings... 

Teflon High melting point, chemical resistance Non-stick surfaces in cookware... 

Nonreactive materials include glass, stainless steel, ceramic, enamel, and hard anodized aluminum. Reactive materials include (non-stainless) steel, cast-iron, copper, and aluminum. These materials conduct heat evenly and are excellent for boiling water, frying burgers, or making stock. But if you re working with acidic or alkaline ingredients, stick to nonreactive cookware. 

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