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Abstract

This article describes the synthesis of dispersions consisting of irradiated poly(tetrafluoroethylene) (PTFE) micropowder in an ester oil (Synative ES TMP 05) and presents their results of the characterization in terms of stability and rheology.

The degree of PTFE micropowder in the dispersion was gradually increased from 10 wt% to 25 wt%. In addition, two additives based on phosphoric acid were used to study whether they are able to affect the properties of the dispersion with the lowest concentration of PTFE micropowder.

The amount of irradiated PTFE micropowder affects the stability against separation. The dispersion with the lowest concentration of PTFE micropowder (10 wt%) showed the highest stability due to the pronounced high fine fraction of PTFE particles (Ø: 0.2–0.5 µm). On the other hand, the PTFE/oil dispersions with higher concentrations own a distinctive amount of greater particles (Ø: 0.3–3.0 µm), suggesting a negative influence on the stability of the dispersions. Nevertheless, these dispersions can stabilize themselves by these structures.

Keywords

Poly(tetrafluoroethylene)ester oil-containing dispersions stability rheological characterization

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Additives for lubricants containing poly(tetrafluoroethylene). Part 1: Synthesis and rheological characterization

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