Robert Christopher Cavanaugh

US Patent:

7390448, Jun 24, 2008

Filed:

Jul 28, 2006

Appl. No.:

11/494893

Inventors:

Devin Flowers - Kennett Square PA, US
Clay Woodward Jones - Washington WV, US
Robert John Cavanaugh - Cincinnati OH, US

Assignee:

E.I. du Pont de Nemours and Company - Wilmington DE

International Classification:

D01F 6/12

US Classification:

264127, 524500, 525191, 428421

Abstract:

A process for dispersion spinning non-melt-processible fluoropolymer fiber in which a mixture of an aqueous dispersion of non-melt-processible polytetrafluoroethylene or modified polytetrafluoroethylene fluoropolymer particles and an aqueous solution of matrix polymer is formed. The non melt-processible particles have an SSG of less than about 2. 40. The aqueous dispersion contains an aliphatic alcohol ethoxylate nonionic surfactant having a 20% residuals temperature determined by thermogravimetric analysis (TGA) of less than about 290 C. and is essentially free of surfactants containing aromatic groups. The dispersion has a fluorinated surfactant content of less than about 300 ppm. The mixture is extruded into a coagulation bath containing a concentration of ions which coagulate the matrix polymer to form an intermediate fiber structure. The intermediate fiber structure is sintered to decompose the matrix polymer and coalesce. The present invention also provides a spinning composition useful for the dispersion spinning of non-melt-processible fluoropolymer fiber.

US Patent:

7985361, Jul 26, 2011

Filed:

May 21, 2008

Appl. No.:

12/124271

Inventors:

Devin Flowers - Kennett Square PA, US
Clay Woodward Jones - Fort Collins CO, US
Robert John Cavanaugh - Cincinnati OH, US

Assignee:

E. I. du Pont de Nemours and Company - Wilmington DE

International Classification:

D01F 6/12

US Classification:

264127, 428421, 524500, 525191

Abstract:

A process for dispersion spinning non-melt-processible fluoropolymer fiber in which a mixture of an aqueous dispersion of non-melt-processible polytetrafluoroethylene or modified polytetrafluoroethylene fluoropolymer particles and an aqueous solution of matrix polymer is formed. The non melt-processible particles have an SSG of less than about 2. 40. The aqueous dispersion contains an aliphatic alcohol ethoxylate nonionic surfactant having a 20% residuals temperature determined by thermogravimetric analysis (TGA) of less than about 290 C. and is essentially free of surfactants containing aromatic groups. The dispersion has a fluorinated surfactant content of less than about 300 ppm. The mixture is extruded into a coagulation bath containing a concentration of ions which coagulate the matrix polymer to form an intermediate fiber structure. The intermediate fiber structure is sintered to decompose the matrix polymer and coalesce. The present invention also provides a spinning composition useful for the dispersion spinning of non-melt-processible fluoropolymer fiber.

US Patent:

56908784, Nov 25, 1997

Filed:

Aug 9, 1996

Appl. No.:

8/693630

Inventors:

William Howard Tuminello - Newark DE
Robert John Cavanaugh - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C08J 518

US Classification:

264203

Abstract:

Perfluorinated cycloalkane solvents for dissolving high melting polymers containing tetrafluoroethylene, are disclosed. These solvents dissolve such polymers more rapidly, and/or are more stable, than previously known solvents. Also disclosed is a process for dissolution of the polymers and their resulting solutions. The solutions are useful for making polymer films, coatings and for encapsulating objects.

US Patent:

52370496, Aug 17, 1993

Filed:

Aug 28, 1992

Appl. No.:

7/936446

Inventors:

Robert J. Cavanaugh - Wilmington DE
William H. Tuminello - Newark DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C08F 600
C09J 1106
C09J12712

US Classification:

528491

Abstract:

A process for purifying fluoropolymers by contacting them at temperatures above 140. degree. C. with a liquid perfluorinated cycloalkane. The resulting polymers are particularly useful where polymers with reduced impurities are desirable, such as in medical devices and in parts for the semiconductor manufacturing industry. The liquid perfluorinated cycloalkanes improve the adhesion of fluoropolymer to themselves and other materials.

US Patent:

56835574, Nov 4, 1997

Filed:

Aug 9, 1996

Appl. No.:

8/692816

Inventors:

William Howard Tuminello - Newark DE
Robert John Cavanaugh - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

B29C 5100

US Classification:

264164

Abstract:

Perfluorinated cycloalkane solvents for dissolving high melting polymers containing tetrafluoroethylene, are disclosed. These solvents dissolve such polymers more rapidly, and/or are more stable, than previously known solvents. Also disclosed is a process for dissolution of the polymers and their resulting solutions. The solutions are useful for making polymer films, coatings and for encapsulating objects.

US Patent:

56520255, Jul 29, 1997

Filed:

Aug 9, 1996

Appl. No.:

8/694735

Inventors:

William Howard Tuminello - Newark DE
Robert John Cavanaugh - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

B05D 302

US Classification:

4273855

Abstract:

Perfluorinated cycloalkane solvents for dissolving high melting polymers containing tetrafluoroethylene, are disclosed. These solvents dissolve such polymers more rapidly, and/or are more stable, than previously known solvents. Also disclosed is a process for dissolution of the polymers and their resulting solutions. The solutions are useful for making polymer films, coatings and for encapsulating objects.

US Patent:

54591910, Oct 17, 1995

Filed:

Mar 31, 1994

Appl. No.:

8/220477

Inventors:

William H. Tuminello - Newark DE
Robert J. Cavanaugh - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C08J 502

US Classification:

524462

Abstract:

Perfluorinated cycloalkane solvents for dissolving high melting polymers containing tetrafluoroethylene, are disclosed. These solvents dissolve such polymers more rapidly, and/or are more stable, than previously known solvents. Also disclosed is a process for dissolution of the polymers and their resulting solutions. The solutions are useful for making polymer films, coatings and for encapsulating objects.

US Patent:

53289463, Jul 12, 1994

Filed:

Aug 28, 1992

Appl. No.:

7/936449

Inventors:

William H. Tuminello - Newark DE
Robert J. Cavanaugh - Wilmington DE

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C08J 502

US Classification:

524462

Abstract:

Perfluorinated cycloalkane solvents for dissolving high melting polymers containing tetrafluoroethylene, are disclosed. These solvents dissolve such polymers more rapidly, and/or are more stable, than previously known solvents. Also disclosed is a process for dissolution of the polymers and their resulting solutions. The solutions are useful for making polymer films, coatings and for encapsulating objects.