Professional Detailing2 min read

Coating Rheology: Preserve Pre-Shear and Recovery History

The preparation sequence before a rheology measurement belongs in the test record. Two nominally identical samples may not have experienced the same handling, conditioning or waiting period.

Updated · NANOLAB Knowledge

The key distinction

Pre-shear and subsequent recovery can be relevant to rheology testing. Where the method specifies them, preserve the actual sequence so a later reviewer can understand how the reported sample state was established.

Practical checks

  1. Identify the required preparation and rest sequence.
  2. Record deviations and actual timing.
  3. Compare results only with the laboratory's assessment of method equivalence.

Example

Illustrative example: one sample is measured immediately after the preparation stage while another waits for a different interval. The discrepancy is investigated before attributing the entire difference to formulation composition.

Scope and limits

Do not introduce a pre-shear routine from this article or alter an established procedure informally. The responsible laboratory should determine whether and how preparation history matters for the particular coating system.

Related guidance

Technical references: Anton Paar: avoiding rheometry measurement errors. These sources describe their stated methods or products; they do not certify NANOLAB products or establish compatibility with an unlisted surface.

Ask NANOLAB about the exact product and intended use. Use the current product documentation for formulation-specific instructions.