Like other physical property characterization methods, rheometry is not a straightforward push-button-get-answer technique. A rheometer is only helpful when the professional designing the tests understands what variables to apply and how to interpret the data. Rheologists use their expertise to improve quality control, product development, and research for a variety of soft materials and fluids. Read below to learn how adding a rheologist to your team can help speed up product releases, avoid process failures, and trouble-shoot raw material issues.
Chemical analyses alone do not provide insights for flow behavior. Although organic and synthetic chemists are valuable contributors, they are not educated in soft material mechanics. Scientists who run chemical analyses should not expected to have full knowledge of the physics of colloids, gels, and solutions. In most cases, the chemists do their best to pick up rheology but struggle with identifying physical phenomena that are independent of (or less correlated to) the sample chemistry. Polymer chain interactions, sedimentation, and gel fracture are well known to rheologists, who can help chemists understand how their samples will behave during manufacturing and when used by a consumer.
Rheology data should be collected to serve a specific purpose. Many manufacturers collect flow curve data simply for historical reasons, without applying the results to improving processes and formulations. In those companies, technicians run samples without regard to the appropriate test settings or reasoning behind obtaining meaningful data. A rheologist can rewrite a quality control test procedure to ensure that the data collected is valid. They can also predict the impact of various formulations on processing, use, and storage. Avoiding wasted material (and wasted money!) is one key advantage of having a rheologist.
Sample testing should implement the latest techniques to save time. Some companies have the best rheometers available on the market, and of those, more than a few of them run their rheometers using outdated methods. A rheologist would redesign test methods to provide more information on the sample structure, which may reduce the time required by replacing multiple tests with just one. Their ability to quickly identify troublesome flow behavior enables them to investigate properties that matter most instead of running huge sample sets over and over. Correlations between sample structure and data can also be made by rheologists with use of rheology models and literature comparisons, which non-rheologists are typically not trained to do.
Modern rheometers are expensive and complex. Lab managers first need proper training to maintain and oversee the use of any instrument, and there is a large knowledge gap for rheometers. The motor incased in modern rheometers typically uses electromagnets and a levitating air bearing to maintain the high sensitivity and precision. Damage to such a motor can cost over $20,000 for repairs. Needless to say, rheometer upkeep is very important. Additionally, sample loading in the rheometer is unlike loading from spectrometers. This difference comes from the sensitivity of the rheometer’s motor and the impact of the surrounding environment on the data. Scientists and technicians who use the instrument need to be properly trained in order to protect the company’s investment.
Rheology work does not need to be difficult for scientists and technicians – let rheologists help guide you in the right direction!
Looking for a rheologist? Contact us to learn how Murray Rheology Consulting can help.