Polytetrafluoroethylene Coated Glass Fibre ( PTFE 75 / Glass 25 ) - Properties and Applications - Supplier Data by Goodfellow

Polytetrafluoroethylene coated glass fabric (PTFE 75/ Glass 25) are fabrics woven from continuous filament glass yarns and coated with polytetrafluoroethylene (PTFE) to give a stiff, flexible, fairly smooth surfaced material that is chemically inert with excellent release properties.

Polytetrafluoroethylene (PTFE) is a fully fluorinated polymer which is semi-crystalline, semi-opaque, and white. It has exceptional chemical resistance being unaffected by nearly all chemicals and also has a very high oxygen index (i.e. is fundamentally non-flam).

It has a very low coefficient of friction and is stable in high temperatures. It is soft, easily deformed, highly susceptible to creep, and low in strength with poor radiation resistance.

It is relatively expensive and cannot be melt-processed (even though in theory it melts at 327 °C, the melt viscosity of normal grades is virtually infinite) and so is formed by powder sintering metods.


Industrial applications of Polytetrafluoroethylene coated glass fabric (PTFE 75/ Glass 25) include release material, protective curtains and conveyor belts e.g. in food processing machines, seals, high temperature electrical insulation, O-rings, bearings, non-stick coatings and linings for vessels etc. Its rare properties make it valuable for numerous laboratory applications.

Key Properties

The key properties of Polytetrafluoroethylene Coated Glass Fibre ( PTFE 75 / Glass 25 ) are tabulated below.

Table 1. Key properties

Chemical Resistance
Acids - concentrated Good
Acids - dilute Good
Alcohols Good
Alkalis Good
Aromatic hydrocarbons Good
Greases and Oils Good
Halogens Fair
Ketones Good
Electrical Properties
Surface resistivity ( Ohm/sq ) >1013
Volume resistivity ( Ohm.cm ) >1015
Physical Properties
Density ( g.cm-3 ) 2.08
Thermal Properties
Lower working temperature ( °C ) -190 to -60
Upper working temperature ( °C ) 260

About Goodfellow

Goodfellow supplies metals, ceramics and other materials to meet the research, development and specialist production requirements of science and industry worldwide.

Source: Goodfellow.

For more information on this source please visit Goodfellow.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type