It is used to determine the surface tension of polymer dispersions and and rubber latices (natural and synthetic), also the interfacial tension of mineral oils against water which has been shown by practice to give a reliable indication of the presence of hydrophilic compounds under non-equilibrium conditions.

Principle:

SFT--Horizontally suspended ring of thin wire is attached to a Du Nouy type tensiometer and immersed in the liquid under test, then slowly pulled out.Just before the ring detaches itself from the surface of the liquid, the force required reaches a maximum.This force is measured by a torsion balance, inductive pick-up or some other suitable measuring device.

IFT¡ªInterfacial tension is determined by measuring the force necessary to detach a planar ring of platinum wire from the surface of the liquid of higher surface tension, that is, upward from the water-oil interface.To calculate the interfacial tension, the force so measured is corrected by an empirically determined factor which depends upon the force applied, the densities of both oil and water, and the dimensions of the ring.Measurements are made under rigid standardized non-equilibrium conditions in which the measurement is completed within 1min after formation of the interface.

Feature:
Fully automatic SFT and IFT measurement

Extremely simple user-friendly operation

Robust force measuring system

LCD display

Digital output for computer and print
Technical Parameters:

Test method:Ring method