Refractive index

OELCHECK test instrument: Mettler-Toledo Brechzahl-Modul RX40
Sample quantity: 20 ml
Unit: none
Test result:

refractive index

calculated with refractive index: glycol concentration, freezing point
Result range: 1.3200 – 1.7000
Analysis for: coolants
Brief description: The refractive index, commonly known as optical density, is an optical material property. Every material has its own characteristic refractive index. Since ethylenglycol, propylene glycol and water have different refractive indexes their amount in a coolant can be determined by the measured value.

On the basis of the refractive index the concentration of ethylenglycol or propylene glycol is determined. The glycol content primarily influences the thermal characteristics of a coolant.

As the concentration is linked to the additive content it considerably incluences the corrosion protection. Furthermore, it is possible to distinguish between ethylenglycol and propylene glycol with the density. A mixture with a third component can change the refractive index or rather the density. With the ethylenglycol concentration a theoretical freezing point can also be output.

Underlying test standard: ASTM D3321