Moving die rheometer, method of testing materials therewith, and die for use therein
AssigneeMonsanto Company
InventorsMichael J. Danko, Leslie L. Randall, Ray J. Smith, James E. Walsh
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Abstract
The rheological properties of a viscoelastic material are measured by enclosing a sample of the material between two die members which have protrusions extending therefrom and intermeshing to form shear zones therebetween. The sample is sheared by displacing one member with respect to the other and the displacement force is measured. A die is provided for the test, and means to bias the die members toward each other, to seal them together, to move one member with respect to the other and to measure the force required for such movement are provided.
Claims39
The method of testing a viscoelastic material comprising the steps of
- substantially enclosing a sample of the material between two opposing die members having protrusions extending therefrom between the members, which protrusions interlock to form shear zones therebetween,
- shearing the sample in the shear zones by displacing one die member with respect to the other, and
- measuring the force required for such displacement.
Apparatus for testing rheological properties of viscoelastic material comprising, in combination, a die having two opposing faces and annular wall means attached to at least one of said faces, annular sealing means arranged to contact said wall means, said faces wall means and sealing means defining a closed space, each face having at least one annular protrusion extending therefrom toward the opposing face, the annular protrusions from one face intermeshing with the annular protrusions from the opposing face, means biasing said faces towards one another, means for rotating one of said faces with respect to the other, and measuring means for measuring rheological properties of a viscoelastic material contained in said die.
In a die adapted to apply shear stress to a sample of viscoelastic material contained therein, comprising, in combination, two opposing faces, annular wall means attached to at least one of said faces and annular sealing means arranged to contact said wall means, the improvement wherein each of said faces has at least one annular protrusion extending therefrom toward the opposing face, the annular protrusions from one face intermeshing with the annular protrusions from the opposing face.
Dependencies are inferred from the claim text.