Multifunction processability testing method and apparatus
AssigneeMonsanto Company
InventorsRobert I. Barker, David P. King, Henry A. Pawlowski
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Abstract
A method and apparatus for testing samples of viscoelastic materials are shown, in which the sample is contained under pressure between two dies and the forces involved in rotating one die with respect to the other. The method uses different frequencies of oscillatory rotation at different temperatures. The apparatus uses dies with discontinuous protrusions which overlap each other.
Claims31
The method of testing a sample of viscoelastic material enclosed under pressure between two opposing temperature-controlled dies by oscillatory rotation of one die with respect to the other and measurement of the reaction torque comprising the steps of
- A. holding the sample at a predetermined temperature while measuring the reaction torque at two or more oscillatory frequencies, and
- B. holding the sample at another predetermined temperature higher than that of step A while measuring the reaction torque at one or more oscillatory frequencies.
The method of claim 15 wherein the loss tangent (tan .beta.) is calculated.
Apparatus for measuring properties of a viscoelastic material comprising, in combination,
- two opposed dies adapted to contain therebetween a sample of the material to be tested,
- means biasing the dies towards each other to apply pressure on the sample,
- means controlling the temperatures of the dies,
- means to rotate one of the dies with respect to the other and
- means to measure the force required for such rotation as applied torque or reaction torque,
- wherein each of the dies has at least one annular protrusion extending therefrom towards the other arranged so that when the dies are biased together an annular protrusion from one die overlaps an annular protrusion from the opposing die, and each of the protrusions is discontinuous.
Dependencies are inferred from the claim text.