bushes in ptfe

PTFE (polytetrafluoroethylene) is a polymer that has its own incredible characteristics such as non-toxicity, temperature range, chemical inertness, flowability, dielectricity, processability and non-stickiness (which is perhaps its most famous characteristic) that make it excellent for certain applications, perhaps one of the characteristics in which it is not exactly excellent (if we have to find one in particular) but this drawback can be remedied.

As we said, one of the limitations of the standard PTFE formula is hardness, but variable components can be added to improve the characteristics of the compound in question.

PTFE can be filled with variable components such as glass fibre, graphite, bronze, carbon and other components.

By loaded, we mean that we add other components to the standard PTFE formula, and the combination of these components increases the characteristics of PTFE alone.

This is why we speak of virgin PTFE (i.e. the standard structure) and filled PTFE (where another component is added to the standard PTFE).


Other materials are added during the processing of PTFE. PTFE can be filled with:

  • Glass fibre
  • Coal
  • Bronze
  • Graphite

to name the most frequently used components and these are added in different percentages to improve certain characteristics according to the use of the final product.

PTFE+ Glass fibre

The addition of glass fibre to PTFE can take place in percentages ranging from 5 to 40%, which improves the wear and deformation resistance of virgin PTFE, while leaving its electrical and chemical characteristics largely unaltered.
The added glass fibre slightly increases the coefficient of friction, which is why graphite or molybdenum disulphide is sometimes added to compensate for the effects.

PTFE+ Graphite

Graphite-filled PTFE (with a percentage ranging from 5 to 15 %) is added to improve PTFE’s friction characteristics, graphite in fact maintains a low coefficient of friction, not only does graphite associated with virgin PFTE improve deformation characteristics under permanent load and also wear, it also has a good impact in improving thermal and electrical conductivity.

PTFE+ Bronze

Bronze-enriched PTFE (in percentages ranging from 40 to 60) compared to PTFE has greater wear resistance and better resistance to deformation under permanent load. This filled PTFE also has increased thermal and electrical conductivity.

PTFE+ Carbon

Carbon-filled PTFE (in percentages between 10 and 35) is much more resistant to wear and deformation under constant load. Sometimes small percentages of graphite are added in addition to carbon.
Compared to unfilled PTFE, it is more resistant in highly oxidising environments and improves electrical characteristics.

The list could be much longer of elements that can be loaded together with PTFE, depending on the characteristics needed, the polymer is loaded with different percentages of glass fibre or graphite or other.

Being able to enrich polytetrafluoroethylene is really versatile, it has very good characteristics in itself, but if we need a stronger end product or one with higher conductivity, the addition of other components comes to our aid to achieve a perfect end result for the customer’s use.

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