Patent ID: 7249523

Claim:
A method of making a rheological measurement of the bulk of a sample comprising: disposing the sample to be measured between two opposing surfaces of a fixture; coupling two opposing surfaces of the sample with a corresponding adjacent one of the two opposing surfaces of the fixture to create a secondary sample boundary within the sample; and measuring a rheological parameter of the sample, where coupling two opposing surfaces of the sample with a corresponding adjacent one of the two opposing surfaces of the fixture comprises penetrating at least one of the opposing surfaces of the sample with a plurality of protrusions disposed on the corresponding surface of the fixture. where the plurality of protrusions have distal ends and where coupling two opposing surfaces of the sample with a corresponding adjacent one of the two opposing surfaces of the fixture to create a secondary sample boundary within the sample comprises creating the secondary sample boundary on a plane in the sample relative to the plurality of protrusions, where at the secondary sample boundary, slip is absent because the interface between the fixture and sample is effectively a contiguous sample-to-sample junction between the fixture and the bulk of the sample to serve as an effective fixture-to-sample boundary for rheological purposes with respect to bulk measurement of the sample.