Welcome to WBCS Notebook, where you can ask questions and receive answers from other members of the community.
0 votes
10 views
in INDIAN ECONOMY by (300 points)

Polytetrafluoroethylene

Polytetrafluoroethylene (PTFE), a strong, tough, waxy, nonflammable synthetic resin produced by the polymerization of tetrafluoroethylene. Known by such trademarks as Teflon, Fluon, Hostaflon, and Polyflon, PTFE is distinguished by its slippery surface, high melting point, and resistance to attack by almost all chemicals. These properties have made it familiar to consumers as the coating on nonstick cookware; it is also fabricated into industrial products, including bearings, pipe liners, and parts for valves and pumps.

PTFE was discovered serendipitously in 1938 by Roy Plunkett, an American chemist for E.I. du Pont de Nemours & Company (now DuPont Company), who found that a tank of gaseous tetrafluoroethylene refrigerant had polymerized to a white powder. During World War II it was applied as a corrosion-resistant coating to protect metal equipment used in the handling of radioactive material for the Manhattan Project. For more than a decade after the war, PTFE saw little commercial use, owing to difficulties encountered in devising methods for processing the slippery, high-melting material. DuPont released its trademarked Teflon-coated nonstick cookware in 1960.

PTFE Fine Powders

Chemours is a leading producer of fluoropolymers that include Teflon? PTFE (polytetrafluoroethylene) fine powder resins.

These fine powders may be paste-extruded to create continuous-length PTFE articles such as tubes, tapes, and membranes. PTFE fine powder is the preferred fluoropolymer for many applications, including breathable hydrophobic membranes, aerospace/automotive hoses, and high-performance wires and cables.

Features and Benefits

This family of fine powder fluoropolymer resins offers a wide range of characteristics that include:

Excellent thermal stability

High stress crack resistance

High reduction ratio

Excellent color and clarity

Polytetrafluroethylene ultrafine powder

PTFE ultra-fine powder can be prepared by irradiation at room temperature, followed by ultrafine grinding. Fresh PTFE material, scrap or recycled PTFE waste, etc., can be used to fabricate ultrafine powder. The use of recycled PTFE or waste to produce ultrafine powder can reduce the cost and achieve the recycling of resources. PTFE ultrafine powder is widely used as a functional additive in the fields of engineering plastics, anticorrosion coatings, nonstick coatings, coil coatings, powder coatings, and inks. Shamrock Technologies (the United States), Solvay Company (Italy), Lubrizol Corporation (Germany), Kitamura Company Ltd. (Japan) and many other companies produce PTFE ultrafine powder. In recent years, domestic Chinese enterprises have also made great progress in the technology of manufacturing PTFE ultrafine powder.

The particle size of PTFE powder is usually tens to hundreds of microns, which is suitable for producing PTFE sheet and pipe. PTFE ultrafine powder can be made by polymerization, radiation degradation, and thermal cracking. The irradiated PTFE becomes very brittle, and can be further fabricated into ultrafine powder by grinding or air-jetting. The particle size is closely related to the absorbed dose. The higher the absorbed dose, the lower the relative molecular weight of PTFE, and the smaller the particle size of ultrafine powder. At present, PTFE ultrafine powder is mainly prepared by radiation degradation at home and abroad, since high energy beam can effectively break the molecular chains of PTFE at room temperature. For recycled PTFE, a very high absorbed dose is required for the fabrication of PTFE ultrafine powder. Hence, it is normally irradiated by EB accelerators. PTFE ultrafine powder is mainly used as an additive in lubricating oil and grease, ink, paint, engineering plastics, leather, rubber, etc., in order to improve antifriction and scratch-resistance.

PTFE teflon powder is available as a white powder, often called fine powder. PTFE fine powder is generally converted into usable articles (shapes, wire insulation and tapes, etc) via paste extrusion, followed by post extrusion heating to remove residual hydrocarbon solvents and to increase material density.

Products manufactured with genuine Teflon PTFE fine powder are rated for continuous service temperatures up to 260°C (500°F).

The properties of Teflon PTFE fine powder are very similar to those of standard Teflon? PTFE granular material.

Insulation for wire and cable, tubing, pipe liners, films, sintered and unsintered tapes, micro-porous membranes, heat shrink tubing, bushings, push/pull cables, profile shapes and other end use components requiring a high performance fluoroplastic material.

5 Key Products That Are Enhanced With PTFE Micropowders

Polytetrafluoroethylene (PTFE) micropowders are used as additives in thousands of products. They can add lubricity or improve friction and wear characteristics of base materials. Because PTFE micron powder is milled very fine, it can be compounded in rubber, plastics, or dispersed in liquids. Here are 5 ideal applications:

Printing Inks

PTFE lubricant powders are superior to the conventional anti-scuff agents that are used in inks. They enhance the preparation of offset, heat-set, gravure and flexographic inks. They improve the rub and scuff resistance of printed stock. And they reduce “blocking,” the undesirable adhesion of a painted surface to another painted surface or material, reducing rejects.

In addition, micropowders can be easily dispersed at room temperature to make processing cheaper and more efficient. Their lubrication properties reduce friction so they slide and stack easier, and their temperature resistant properties allow them to be used in temperatures up to 260 °C.

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
To avoid this verification in future, please log in or register.

No related questions found

Welcome to WBCS Notebook, where you can ask questions and receive answers from other members of the community.
...