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US 8,506,864 B2Granted
High molecular weight poly(alpha-olefin) solutions and articles made therefrom
AssigneeHoneywell International Inc.
InventorsThomas Y. T. Tam, Qiang Zhou, John A. Young, Charles R. Arnett, John D. Brodie, Conor J. Twomey, Lori L. Wagner, Sheldon Kavesh
Life of this patent
Estimating the term…
Abstract
A robust process for the continuous preparation of solutions of high molecular weight UHMW PO that is capable of producing strong materials at high production capacity, is conservative of capital and energy requirements, and the articles made therefrom.
Claims29
A process for the preparation of a multi-filament solid UHMW PO yarn having a tenacity of at least 27 g/d from slurries of UHMW PO comprising the steps of:
- a) forming a slurry of UHMW PO particles having an intrinsic viscosity measured in decalin at 135° C. of from 5 to 45 dl/g in a solvent for the UHMW PO at a first temperature which is below the temperature which said UHMW PO will dissolve in said solvent;
- b) processing said slurry through an extruder operating such that a mixture of said solvent and said UHMW PO is formed at a second temperature above the melting temperature of said UHMW PO, and the throughput rate of UHMW PO in said mixture is at least the quantity 2.5 D2 (2.5×D×D) grams per minute wherein D represents the screw diameter of the extruder in centimeters, the mixture containing domains of molten polymer and solvent having sizes of microscopic dimensions;
- c) discharging said mixture from the extruder;
- d) passing said mixture through a heated vessel at a temperature above the melting temperature of said UHMW PO, said vessel having a volume such that the average residence time of the mixture in said vessel is from 2 to 120 minutes, whereby a homogeneous solution of said UHMW PO is formed having the UHMW PO dissolved in the solvent;
- e) passing the thus-formed solution out of said vessel and through a spinneret, said solution being at a temperature below the atmospheric boiling point of said solvent to form a multi-filament solution yarn;
- f) stretching the multi-filament solution yarn;
- g) cooling the multi-filament solution yarn to obtain a multi-filament gel yarn;
- h) stretching the multi-filament gel yarn;
- i) substantially removing the solvent from said multi-filament gel yarn to form a multi-filament solid yarn;
- and
- j) stretching the multi-filament solid yarn in one or more steps at temperatures from 25° C. to 165° C.,
- whereby the resultant multi-filament solid yarn has a tenacity of at least 27 g/d.
9 more elements
A process for the preparation of a multi-filament solid UHMW PO yarn having a tenacity of at least 27 g/d, comprising the steps of:
- a) forming a slurry of UHMW PO particles having an intrinsic viscosity measured in decalin at 135° C. of from 5 to 45 dl/g in a solvent for the UHMW PO at a first temperature which is below the temperature at which said UHMW PO particles will dissolve in said solvent;
- b) processing said slurry through an extruder operating such that a mixture of said solvent and said UHMW PO is formed at a second temperature above the melting temperature of said UHMW PO, and the throughput rate of UHMW PO in said mixture is at least the quantity 2.5 D2 (2.5×D×D) grams per minute wherein D represents the screw diameter of the extruder in centimeters, the mixture containing domains of molten polymer and solvent having sizes of microscopic dimensions;
- c) discharging said mixture from the extruder;
- d) passing said mixture through a heated vessel at a temperature above the melting temperature of said UHMW PO in said solvent, said heated vessel having a volume such that the average residence time of the mixture in said vessel is from 2 to 120 minutes, whereby a homogeneous solution of said UHMW PO is formed having the UHMW PO dissolved in the solvent;
- e) passing the thus-formed solution out of said heated vessel and through a spinneret, said solution being at a temperature below the atmospheric boiling point of said solvent to form a multi-filament solution yarn;
- f) stretching the multi-filament solution yarn;
- and
- g) further processing the multi-filament yarn, including at least one additional yarn stretching step, to form a multi-filament solid UHMW PO yarn having a tenacity of at least 27 g/d.
5 more elements
Dependencies are inferred from the claim text.