Surface tension measurementSurface tension measurement may be made using a Surface Tensiometer. Several techniques are described in literature including optical, pressure and force based methods. Inherent to the most precise of these techniques is to measure the weight of the meniscus.
All Kibron Surface Tension measurement devices utilise the idea developed by *Padday et al in the 1970s where a small diameter rod requiring no correction factors or allowances for geometrical edge effects is automatically immersed and withdrawn from the sample to be measured. This has been found to be quick, accurate and reliable and allows us to offer compact surface tension measurement instrumentation for surface scientists in research, development and even Quality Assurance (QA/QC)
* (J Chem. Soc Far Trans I 71: 1919-1931, 1974).
Our surface tension measurement approach is simplicity itself: a thin rod (instead of a common ring or a plate) is immersed into the sample and withdrawn out and the maximum force is measured by our high resolution microbalance. The diameter of the probe is irrelevant and only a diameter change requires the need to recalibrate. This process is automated and fast in all of the Kibron instruments. When calibration is performed using a liquid of known surface tension there is no need for correction. The weight of the meniscus depends only on surface tension, rod diameter, and the density of the liquid which are all known
Surface tension measurement allows us to understand properties in a system and is an important parameter in characterising a liquids ability to wet a solid surface and to understand adhesion.
The Kibron Aqua Pi/Plus (& Ez-Pi plus) range provide a family of compact, high performance force based surface tension measurement devices for almost any industry.
At the heart of every Kibron surface tensiometer is a high sensitivity, high resolution (better than <0.2ug) microbalance giving unparalleled measurement performance & the ability to make surface tension measurements on very small sample volumes (3ml – 50ul). This is important for high value materials or where the volume is just in short supply.
Beneficially the small diameter rod used in our surface tension measurement (the DyneProbe) may be easily cleaned, re-used and replaced economically should the need arise, it may also be used with more viscous samples than are possible with other systems.
An extensional use of the same DyneProbe allows the rod to be positioned precisely at the liquid interface where weight is then monitored with time without the rod moving. Knowledge of the rod diameter and the measured force allows surface tension measurement with time to be made automatically recorded in software based Kibron Surface Tensiometers (Aqua Pi Plus and Ez-Pi Plus). Equilibrium adsorption times and concentration effects may be studied with this surface tension measurement mode
Our wide range of instruments, complementary accessories and expert know how make us the “Go To” people for surface tension measurement