PTFE Processing: Innovation And Outstanding Performance

Today, thanks to a wide range of technologically advanced equipment, semi-finished PTFE products are produced, whether of the virgin type or loaded with other materials. In both cases, technopolymers can be obtained from an injection moulding process of the highest quality and of different types. TAFER, with headquarters and factory in the province of Bergamo, guarantees the production process by following it step by step from the design phase of the necessary equipment, followed by prototyping and final production.

WHAT IS PTFE?

PTFE or polytetrafluoroethylene is a group of high-performance plastics with unique properties. It represents the most unusual fluoropolymer and offers the best performance in terms of temperature, chemical resistance and non-stick properties. TAFER, a leading company in the sector with headquarters and factory in the province of Bergamo, carries out the processing of PTFE following distinct working processes that are subordinate to the types of materials used. Firstly, a TFE monomer is produced, i.e. an element obtainable through the synthesis of calcium fluoride, sulphuric acid and chloroform. In a second step, polymerisation is carried out under carefully controlled conditions in order to achieve the best result. PTFE once made from chlorofluoride bonds is strong and compact, has exceptional chemical inertness, high heat resistance and remarkable electrical insulation characteristics. However, uninhibited pure tetrafluoroethylene can polymerise violently even at temperatures initially below room temperature. A silver-plated reactor filled a quarter full with a solution consisting of 0.2 parts ammonium persulphate, 1.5 parts borax and 100 parts water and with a pH of 9.2 is sealed and stirred for about an hour at 80°C, after which it is cooled, which eventually yields an estimated polymer yield of around 86%. PTFE, by the way, is commercially produced by two main processes, one leading to the so-called granular polymer, and the second yielding a polymer dispersion with a much finer grain size and lower molecular weight. As an aside, it is worth adding that there are also other methods for the production of PTFE, such as the decomposition of TFE under the influence of an electric arc or by emulsion using initiators such as hydrogen peroxide and ferrous sulphate. In some cases, oxygen is also used as an initiator element. All the above reactions are highly exothermic and must be controlled by experienced company personnel to avoid violent explosions.

WHAT ARE THE PROPERTIES OF PTFE?

The properties of PTFE are manifold and allow it to be used in various ways. This is due to the fact that, unlike plastics, in a polytetrafluoroethylene (PTFE) structure, instead of hydrogen atoms, fluorine atoms are used. However, PTFE does not melt when heated and is therefore difficult to work with. However, appropriate techniques can be adopted to overcome this drawback. Other stabilising and fluidising elements or fillers based on silicon, carbon, bronze and stainless steel are usually added to the virgin polymer. In addition, after injection moulding the finished product is smooth to the touch, resists high temperatures very well, is ideal for patterned gaskets and is non-stick and weather resistant. This working process drastically changes the material’s properties, enabling it to offer a number of indisputable advantages:

• Electrical insulator: PTFE vie frequently used as an insulator for wiring and cables, particularly in computer applications, as it prevents current leakage and has a high melting point.

• Low-friction material: The low friction that characterises PTFE also makes it a popular material in mechanical engineering applications. It is regularly used for bearings and plates, gears and other working parts where sliding action is required.

• Wear-resistant: PTFE is not prone to reactivity and resists high temperatures well, which is why it is also often used for the production of straight and assembled industrial hoses in which chemicals and acids flow.

• Food safe: PTFE once made proves to be an excellent choice for applications in food production and packaging, in particular because the material complies with food quality requirements and is stain-resistant as well as non-toxic.

• Chemically resistant and inert: combined with its high temperature tolerance, PTFE is extremely resistant to chemicals and inert, making it an ideal material for sealing particularly aggressive acidic components.

• Cost-effective material: PTFE is one of the most cost-effective fluoropolymers on the market and has one of the best performance/price ratios. In addition, its resistance to weathering and general wear and tear make it an extremely durable material that is also ideal for window frames.

WHAT IS PTFE USED FOR?

Thanks to its extraordinary properties, PTFE is one of the semi-finished products that can withstand even the harshest environments and, as such, is suitable for use in numerous applications. In fact, this fluoroplastic is suitable for the production of food and beverage containers, the manufacture of special equipment for cooking food, the construction of conveyor belt rollers, casings for temperature sensors and for making various surfaces non-stick. In the chemical industry, PTFE can also be used to make various products, from gaskets to coatings for chemical containers and tanks. PTFE like PEEK is also widely used for fire doors, for terminal insulation on heating elements and on jet engines, UV lamps and external accessories for aircraft. Among other things, PTFE is ideal for use in medical applications and for the manufacture of life-saving equipment such as catheters, biocontainment vessels, syringes and sutures. This unique fluoropolymer is also perfect for electrical insulation, the manufacture of valve components and for the protection of all kinds of electronic components. TAFER is a leader in the PTFE sector and is also involved in the processing of PEEK and metal stamping. The former specifically is a thermoplastic material capable of providing high mechanical and chemical resistance even at very high temperatures. The latter, on the other hand, is indispensable in the production process of sheet metal, as it allows it to be perfectly flat. For more information write or contact us.