Rheometers

Measuring the rheological properties of materials using a NETZSCH rheometer

A rheometer is a device used to measure the rheological properties of materials; rheology being defined as the study of the flow and deformation of matter, which describes the interrelation between force, deformation and time.  

Unlike a viscometer, which can only measure the viscosity of a fluid under a limited range of conditions, a rheometer is capable of measuring viscosity and elasticity of non-Newtonian materials under a wide range of conditions. Some of the most important properties that can be measured using a rheometer include viscoelasticity, yield stress, thixotropy, extensional viscosity, creep compliance and stress relaxation behavior, as well as process relevant parameters such as die swell, melt fracture. 

Rheometer principle

How does it work?

A sample is forced to extrude through a barrel or die of well-defined dimensions under high pressure. The pressure drop across the barrel or die is measured to give pressure-flow rate data for the fluid, from which viscosity is calculated. Temperature and shear rate can be closely controlled to simulate the processing environment of interest.

What is it useful for?

Originating in the polymer industry, capillary rheometry is useful for measuring the viscosity profiles of suspensions and slurries containing relatively large particles, at high particle loadings. Industrial examples include polymer melts, ceramic slurries, foodstuffs, inks and coatings. Capillary rheometers can apply very high force, which enables the exploration of behavior at far higher shear rates than is possible with rotational rheometry. High shear rate performance is pertinent in many industrial processes, such as extrusion and spraying. For certain applications the sample size required for capillary rheometry, around a liter for the generation of a flow curve, is a limitation

Rheometers

Kinexus DSR

Kinexus DSR - A diverse analytical research solution for laboratory testing.

Kinexus DSR-III

Kinexus DSR-III - Complete package for routine QA/QC paving analysis

Kinexus ultra+

Kinexus ultra+ - Highest specification rheometer bearing system

Kinexus DSR+

Kinexus DSR+ - The world’s most sensitive DSR for all construction and petro chemicals testing

Kinexus lab+

Kinexus lab+ - Rotational rheometer for routine and Quality Control testing

Rosand RH2000

Rosand RH2000 - Bench top capillary rheometer for research to QC testing.

Kinexus DSR-E

Kinexus DSR-E - Simple solution for basic research and testing, ideal for the roofing industry

Kinexus pro+

Kinexus pro+ - Research grade rheometer for complex fluids characterization

Rosand RH7/10

Rosand RH7/10 - Robust research capillary rheometers for high force conditions.