“TEFLON®  ” is the registered trade mark of the DuPont company for its fluorocarbon resins. DuPont pioneered the use of TEFLON®   PTFE and FEP   resins following the discovery that they could be made into articles having a combination of mechanical, electrical, chemical temperature and friction-resisting properties unmatched by articles made of any other material. TEFLON®   fluorocarbon resins’ unique combination of physical, electrical and chemical properties have found application in nearly every field of modern industrial, scientific and technological endeavor.

Structurally, there are different types of TEFLON®   resin. TEFLON®   PTFE (Polytet-rafluoroethylene) resin is a polymer consisting recurring units with the formula.

                        (CF₂-CF₂) _n

The maximum molecular weight of this  greater than 90% crystallinic TFE  Polymer  is about 9 x 10₆. PTFE displays a series of unique properties.

• Nearly universal chemical resistance (exceptions: elemental fluorine,  CF₃, molten alkali metals)

• Insoluble in all solvents below 300^oC

• High service temperature stability up to 260^oC

• Very low adhesiveness

• Very low friction coefficient

• Extremely hydrophobic , no water adsorption

• Physiologically inert, contaminant free

• Very good electrical (high resistance) and dielectrical (very low dielectric number and loss factor) properties

• Nonflammable

• Highly weather resistant (UV resistant)

• Good mechanical properties: tough elastic, easily manufactured

These advantages of PTFE, especially its universal chemical resistance, are the reason lab ware and accessories made of PTFE or other fluorocarbon resins are a must in any laboratory. Its broad service temperature range and its unbreakability  are further advantages of PTFE.

Stirrer blades, magnetic stir bars encapsulated in PTFE, joint sleeves, adapters and boiling accessories are just a few of the items available in PTFE along with standard items such as flasks, bottles, dishes, etc. They are indispensable if the chemical resistance of glass or rare metals does not suffice.  Digestion in boiling hydrofluoric acid or boron trifluorides possible as well as hot alkali-hydroxide melts.

Lab ware  made of PTFE resists temperatures of  -200^oC without becoming brittle. The maximum service temperature is  +260^oC     (but 300^oC  is possible for a short time period ). PTFE IS EXTREMELY non-adhesive. This is an advantage for working lacquers, adhesives, resins and hydroscopic substances. PTFE is biologically inert. Therefore it is used in many applications in biology, microbiology, medicine, pharmacy and in the food industry.

Pure PTFE, because of its chemical resistance and its anti-adhesive surface, prevents any sample contamination by abrasion or etching. Vessels made of PTFE therefore are absolutely necessary in trace element analysis methods.

The production of PTFE-ware is performed using the so called isostatic pressing process. PTFE powder is filled informs and isostatically pressed at high pressures. The pressed parts are sintered at temperatures up to 400^oC .The characteristics of the material are substantially influenced by the pressing and sintering process. Porous PTFE is made by controlled sintering of powders with defined particle sizes. Stock PTFE in roads, sheets, etc. are available for customer use.

TEFLON®  PTFE  is the Registered Trade Mark of E.I. Dupont, U.S.A. and we are the direct user of TEFLON® products from E.I. DuPont.

FEP

Similar properties are displayed by FEP:(Fluorinated ethylene propylene)

[CF(CF₃)-CF₂(CF₂-CF₂) _n]_m

The molecular weight of this copolymer is 50,000 to 500,000 and the crystallinity is about 50%. The maximum service temperature of  205^oC   is lower than PTFE. FEP is thermoplastically moldable (injection molded at temperatures of  320^o - 360^oC  extruded at 350^o - 410^oC) is translucent, flexible and feels heavy because of its high density . FEP has the greatest clarity of the three types of TEFLON®  .

TEFLON®  FEP is the Registered Trade Mark of E.I. Dupont, U.S.A. and we are the direct user of TEFLON® products from E.I. DuPont.

PFA

PFA (perfluoroalkoxy) has the same advantages as PTFE TEFLON®   with the structure:

[ CF(OR₁)-CF₂(CF₂-CF₂)_n]_m    

R represents C_nF_2n+1

PFA can be melt processed (extruded). The chemical resistance is comparable to PTFE. PFA is translucent and slightly flexible. It has greater mechanical strength than PTFE. Its melting  temperature is 305^oC    and maximum operating temperature is 260^oC.

PFA was first used in the semiconductor  industry for injection molded wafer carriers and similar articles that resisted aggressive chemicals and high temperature chemical processing .  Now, PFA is also considered  to be the best TEFLON®   for semiconductor  piping applications, and is accepted for both liquid reagent and UPDI water  handling in advanced processing applications.

TEFLON®  PFA is the Registered Trade Mark of E.I. Dupont, U.S.A. and we are the direct user of TEFLON® products from E.I. DuPont.