High temperature continuous viscometry coupled with analytic temperature rising elution fractionation for evaluating crystalline and semi-crystalline polymers

Patent 4798081 Issued on January 17, 1989. Estimated Expiration Date:

December 22, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3837217

Polymer characterization apparatus
Patent #: 4258564
Issued on: 03/31/1981
Inventor: Hulme , et al.

Viscosity measurement
Patent #: 4286457
Issued on: 09/01/1981
Inventor: Johnson, Jr.

Differential pressure capillary viscometer for measuring viscosity independent of flow rate and temperature fluctuations
Patent #: 4578990
Issued on: 04/01/1986
Inventor: Abbott , et al.

Differential pressure capillary viscometer for measuring viscosity independent of flow rate and temperature fluctuations Patent #: 4627271
Issued on: 12/09/1986
Inventor: Abbott , et al.

Inventors

Application

No. 07/137118 filed on 12/22/1987

US Classes:

73/53.01, LIQUID ANALYSIS OR ANALYSIS OF THE SUSPENSION OF SOLIDS IN A LIQUID73/54.04, Friction tube (e.g., capillary)73/54.11, Orifice, nozzle, or extrusion means73/54.14By force, pressure, or displacement measuring

Examiners

Primary: Levy, Stuart S.
Assistant: Roskos, Joseph W.

Attorney, Agent or Firm

International Classes

G01N 11/08 (20060101)
G01N 11/00 (20060101)
G01N 25/14 (20060101)
G01N 33/44 (20060101)
G01N 25/00 (20060101)
G01N 30/00 (20060101)
G01N 30/02 (20060101)
G01N 30/62 (20060101)
G01N 30/32 (20060101)

Abstract

A method and apparatus for analyzing a solution of a crystalline or a semi-crystalline polymer sample to determine a crystallinity versus weight percent profile concurrently with viscosity average molecular weight. The polymer sample is first precipitated from solution over a cooling temperature gradient to produce a precipitated polymer sample, which is precipitated as a function of its crystallinity. The precipitated polymer sample is then eluted and redissolved over a heating temperature gradient to produce successive fractions of a fractionated polymer sample solution, which are measured to produce concentration and specific viscosity data from which the intrinsic viscosity and viscosity average molecular weight are calculated.