Rheomicroscopy – simultaneous determination of rheology and structure

Crystallisation of polymers and fat is complex and difficult to explain, as is process effects during incipient structure formation. The explanation is considerably easier when you can measure material properties while simultaneously observing the microstructure – this is Rheomicroscopy.

By combining rheometry and microscopy it is possible to determine the underlying mechanisms responsible for deformation-induced structure breakdown (thixotropy) and formation (rheopexi), droplet break-up in emulsions, particle aggregation and breakup in dispersions, melting of fat and polymers and more. Such mechanisms drive texture formation and breakdown in food applications (oral processing and industrial processing), limit shelf-life and determine tactile perception of cosmetics as well as regulating structure formation in cementitious and other construction materials (additives, coatings, fibre alignment in 3D-printing formulations).

A laser equipped microscope is mounted under a glass plate in an advanced rheometer. The sample is enclosed between the glass plate and an upper heat-controlled plate, and observed from below while shearing, compressing or oscillating the sample. The two plates can be counter-rotated to form a stagnant layer for fixed observation during shearing. The microscope is equipped with polarisers for polarization microscopy and a filter for fluorescence microscopy. The rheomicroscope setup is a Modular Microscope Acessory from TA Instruments.

Below you can see some examples of rheomicroscopy in different applications.