All fluoroplasticsGlossaryfluoroplasticsbelong to the group of thermoplastics., PTFEGlossaryPTFEPolytetrafluoroethylene , PFAGlossaryPFA Perfluoroalkoxy and FEPGlossaryFEPTetraflouroethylene-Perflouropropylene have a smooth, non-wetting surface and can usually be cleaned without any problems. Abrasive scouring agents might damage the surface and result in a milkiness of the vessels – especially those made of PFAGlossaryPFA Perfluoroalkoxy and FEPGlossaryFEPTetraflouroethylene-Perflouropropylene. You may use all neutral detergents (pH 7). For a stronger contamination we recommend to use an alkaline detergent up to pH 12. Clean or dry vessels in a laboratory washing machine only when they are completely opened.
Vessels made of PTFEGlossaryPTFEPolytetrafluoroethylene , PFAGlossaryPFA Perfluoroalkoxy or FEPGlossaryFEPTetraflouroethylene-Perflouropropylene can be autoclaved or sterilised at +121 °C. This can for example be made in the steam space or in dry conditions at +160 °C. All vessels with screw covers or stoppers have to be open while being autoclaved. Autoclaving of closed vessels will result in their deformation or destruction.
To prevent contamination with cations or anions in trace analysis, the vessels should first be filled with a 1NHCL and HNO3 solution. This solution should be allowed to stand for a maximum of 6 hours at room temperature. The vessels should then be rinsed with clean deionized water.
Due to their thin walls, standard PTFEGlossaryPTFEPolytetrafluoroethylene , PFAGlossaryPFA Perfluoroalkoxy or FEPGlossaryFEPTetraflouroethylene-Perflouropropylene bottles should not be pressurised (from inside). Pressurisation could result in permanent deformation.
When heating with a heating mantle, a large surface of the vessel is covered. This supports the heat transmission and reduces the heating period. The mantle must have a sensor on its surface. This probe measures the temperature on the surface of the PTFEGlossaryPTFEPolytetrafluoroethylene and switches the mantle of upon exceeding +260 °C. Only this way temporary overheating and harmful decomposition products are avoided.
We advise against the use of “usual” heating mantles and control systems. Their use may result in the same effects as the use of hotplates.
The heat transmission is provided by the bath medium (oils or other liquids). Controlled by an adjusted thermostat the temperatures on the surface of the PTFEGlossaryPTFEPolytetrafluoroethylene vessel will not become too high. Depending on the immersion depth, a big surface for a good heat transmission is provided. The only disadvantage is the danger which occurs when working with oils at high temperatures.
Flame (e.g. gas burner):
With this method, the surface temperature cannot be controlled. Due to temporary overheating harmful decomposition products can occur.
Overheating can occur as well. Usual hotplates can only be switched on or off. During the heating period, the plate is heated with full energy so that it almost glows. Afterwards, the hotplate is switched off and only heats for a few seconds. This so-called „pointing“ is enough to exceed the maximum temperature of +260 °C. It does not make sense to put the adjusting knob only to +150 °C. PTFEGlossaryPTFEPolytetrafluoroethylene labware char on the underside and glue to the hotplate. The thermoplastics PFAGlossaryPFA Perfluoroalkoxy and FEPGlossaryFEPTetraflouroethylene-Perflouropropylene melt directly, similar to a hot-melt-type adhesiveGlossaryadhesiveDue to polarity, a substance has a certain power which allows it to adhere to another substance, for example liquids adhere to walls of containers. BOLA labware normally has non-adhesive properties.. This can be prevented by putting an aluminium foil between hotplate and vessels but dangers for health cannot be avoided.