The first question is, "What are Liquid Properties?" Are they some kind of underwater real estate?

Read More

Topics: Automatic Surface Tension Measurment, Measure Viscosity, Consistency, contact angle, Liquid Properties, density

Looking at the rotational viscometers on the market today, you'd expect to see small price differences between the instruments offered by competing brands. But what if you find one viscometer priced at $2000 and another at $9000? Is the $9000 viscometer a better instrument? Why is there such a price difference between the two instruments? 

Viscometer prices depend on both the make-up of the instrument's motor, and on the technical features of the instrument (temperature probe, speed range, USB compatibility, etc.). There are two main types of rotational viscometers: those using a spring motor, and those using a servo motor. 

In this article, I’m going to take a look the options available for rotational viscometers, and how those options affect the price.

Read More

Topics: Viscometers, Viscosity, Dynamic Viscosity, rotational viscometer, Liquid Properties

Most rotational viscometer specifications promise high test accuracy and repeatability. However, an instrument on its own cannot guarantee accurate results. Instrument set-up and using the right test parameters are critical pieces of the puzzle. 

Test parameters and turbulence are two key factors to consider when preparing to test with a rotational viscometer. The spindle, speed setting, and temperature of the product are some of the parameters that can impact test results. Additionally, turbulence in the sample’s flow during a test will distort viscosity readings. Knowing how to manage these two factors can significantly contribute to the accuracy of your testing.

Read More

Topics: Measure Viscosity, Viscometers, Viscosity, Dynamic Viscosity, rotational viscometer, Liquid Properties

Loss on Drying (LOD) Moisture Balance analysis is based on drying a sample and comparing the difference in weight before and after drying. 

Read More

Topics: Moisture Testing, Loss-On-Drying, moisture balance

This is an update of an article originally published in December 2013 - Three years ago.

Read More

Topics: Automatic Digital Tensiometer, Automatic Surface Tension Measurment, Surface Tension Measurement, Surface Tension, du Nouy tensiometer, Liquid Properties, surface tension instruments, surface tension analysis, Digital tensiometer, automatic Tensiometer

Quiet Sieve Shakers

Recently in a quiet, reflective moment, I recalled my first work with sieve shakers. Horizontal motion with tapping was the basic shaker design. The Ro-Tap® was King, and there were few alternatives. Different shakers for special applications, such as the Mary Jane and one that was hung from the ceiling, were the exception. 

Read More

Topics: Sieve Shakers, Sonic Sifter, Particle Size Analysis, Quiet sieve shakers, RoTap, Noisy Sieving, sieving, Endecotts, vacuum sievers

You probably know that rotational viscometers work by measuring the torque on a vertical shaft that rotates a spindle.  The spindle is in the test sample and its rotation is impeded in proportion to the viscosity of the sample. These instruments measure viscosity.

Read More

Topics: Viscometers, Viscosity, Liquid Properties

An understandable definition of surface tension: “The attraction force between molecules at the surface of a liquid. The force that keeps if from flying off into space”.

Read More

Topics: Tensiometer, Surface Tension Measurement, Surface Tension, actual surface tension, apparent surface tension, Liquid Properties

A classical definition of Contact Angle:

Read More

Topics: Surface Tension, contact angle, contact angle meter, dynamic contact angle, Liquid Properties

Contact angle and surface tension. The two terms are never far apart. Run a Google search of "contact angle" right now and see for yourself. You'll often see the terms mentioned within a breath of one another because contact angle and surface tension are two approaches to surface analysis - the study of how a surface interacts with other materials or components. Generally speaking, there is also a relationship between the two measurements, one that tends not to be very clearly explained in other resources. I hope to remedy that today.

Read More

Topics: Automatic Surface Tension Measurment, Surface Tension Measurement, Surface Tension, contact angle, contact angle meter, wettability, Liquid Properties