TRACKER - EXAMPLE 2

INTRODUCTION :

This note gives some example of the measurement low interfacial tensions, with the TRACKER.

PROTOCOL :

1/ Products :

• Oils / phase 1: 4 samples labelled A, B, C and E

• Oil / phase 2: 1 sample labelled D

2/ Measurement conditions:

• Temperature : 25°C (+/- 1°C)

• Duration of each measurement : 30 minutes

• Volume of the drops (phase 1)

- 0.6 µl for oil B
- 0.003 à 0.05 µl for oil A
- 0.003 to 0.05 µl for oil E
- 0.4 µl for oil C

3 / Cleaning of the requisites (cell, syringe & capillary) :

• washing with a solvent

• rinsing with ethanol

• rinsing with distilled water

• checking of the cleanness at the air/water interface (interfacial tension at the air/water interface measured during six hours: no drift).
  

RESULTS :

1/ Images of the drops : OIL E with OIL D

Results : Volume of the drop = 0.003 µl Interfacial tension = 0.012 mN/m 5 minutes after the formation of the drop Density of the oil E (drop) = 0.96 (g/cm3) Density of the oil D (Bulk) = 0.86 (g/cm3) Temperature 25 °C

Results : Volume of the drop = 184 µl Interfacial tension = 22.2 mN/m 30 minutes after the formation of the drop Density of the water E (drop) = 0.997 Density of the oil E (Bulk) = 0.86 (g/cm3) Temperature 25 °C

Typical record

Note :

This experiment has been implemented in 1998, when the TRACKER was still running under DOS, and yet with Windows, as today.