Paul S Chen

US Patent:

20070166344, Jul 19, 2007

Filed:

Jan 18, 2006

Appl. No.:

11/334049

Inventors:

Xin Qu - East Brunswick NJ, US
Rainer Gruening - Basking Ridge NJ, US
Karen Merritt - Hillsborough NJ, US
Paul Chen - Canandaigua NY, US
Vitaly Falevich - Parsippany NJ, US

International Classification:

A61K 31/787
A61F 2/02
C08G 63/91
C08L 75/00

US Classification:

424423000, 424405000, 424078300, 525127000, 525054200

Abstract:

Surface-active, non-leaching antimicrobial film forming compositions and methods for their application to preferably medical device surfaces are provided. The compositions form durable coatings with long-lasting antimicrobial efficacy without formation of a zone of inhibition. Optionally the films can be hydrophilic. Specific long-chain molecules of certain chemical reactivity are covalently bonded into a polymeric matrix. They maintain a long-term anti-microbial efficacy without being leached out into the aqueous environment. The polymeric matrix of the compositions contain functional groups, which covalently bond to an amine, thiol, carboxyl, aldehyde or hydroxyl active group of selected long chain quaternary ammonium compounds. Upon formation of a covalent bonding with the polymeric matrix the long chain compounds become immobilized but still maintain antimicrobial efficacy. They do not leach out over extended period of time into the aqueous environment and maintain an anti-microbial efficacy against microorganisms. The coating is useful to prevent bacterial colonization on a variety of surface including surfaces of medical devices.

US Patent:

51208261, Jun 9, 1992

Filed:

Dec 21, 1990

Appl. No.:

7/631559

Inventors:

Rohitkumar H. Vora - Westfield NJ
Paul N. Chen - Gillette NJ

Assignee:

Hoechst Celanese Corp. - Somerville NJ

International Classification:

C08G 6926
C08G 6928
C08G 7314

US Classification:

528350

Abstract:

The present invention provides for a novel heat stable class of polyamide-imide polymers having excellent flow properties and hydrolytic stability which are prepared by forming the polycondensation product of one or more aromatic or aliphatic diamines and a comonomer comprising a tri- or hexafluoro-substituted tricarboxylic acid anhydride (or acid derivative thereof) having the structure: ##STR1## wherein R is CF. sub. 3 or a phenyl radical. In addition to improved flow properties, the polyamide-imide polymers of this invention also exhibit improved solubility properties in most organic solvents, good resistance to attack by chlorinated solvents such as trichloroethylene as compared with polyimides, improved hydrophobic properties as well as good thermal properties, including resistance to thermooxidative degradation.

US Patent:

51091070, Apr 28, 1992

Filed:

Dec 21, 1990

Appl. No.:

7/631558

Inventors:

Rohitkumar H. Vora - Westfield NJ
Paul N. Chen - Gillette NJ

Assignee:

Hoecht Celanese Corp. - Somerville NJ

International Classification:

C08G 6926
C08G 6928

US Classification:

528350

Abstract:

The present invention provides for a novel heat stable class of polyamide-imide polymers having excellent flow properties and hydrolytic stability which are prepared by forming the polycondensation product of one or more aromatic or aliphatic diamines, one or more additional comonomers selected from the group consisting of a tetrafunctional aromatic dianhydride, an aromatic or aliphatic dicarboxylic acid (or acid derivative thereof) and mixtures thereof, and a comonomer comprising a tri- or hexafluoro-substituted tricarboxylic acid anhydride (or acid derivative thereof) having the structure: ##STR1## wherein Z is CF. sub. 3 or a phenyl radical. In addition to improved flow properties, the polyamide-imide polymers of this invention also exhibit improved solubility properties in most organic solvents, good resistance to attack by chlorinated solvents such as trichloroethylene as compared with polyimides, improved hydrophobic properties as well as good thermal properties, including resistance to thermooxidative degradation.

US Patent:

51208253, Jun 9, 1992

Filed:

Dec 21, 1990

Appl. No.:

7/631557

Inventors:

Rohitkumar H. Vora - Westfield NJ
Paul N. Chen - Gillette NJ

Assignee:

Hoechst Celanese Corp. - Somerville NJ

International Classification:

C08G 6926
C08G 802
C08G 6300
C08G 1200

US Classification:

528350

Abstract:

The present invention provides for hybrid polybenzimidazole and polybenzimidazolone polymers which are characterized as containing both imidazole and imidazolone structural units in the polymer chain. These polymers are characterized as containing at least one recurring monomer unit containing the structure of the formula: ##STR1## wherein Ar is a tetravalent aromatic moiety derived from an aromatic tetraamine and Ar. sub. 1 is a trivalent aromatic moiety derived from a trifunctional acid, an acid anhydride or amine-reactive derivatives thereof, said polymers further characterized by an inherent viscosity of at least about 0. 01 dl/g measured as a 0. 5% solution in N-methyl pyrrolidone at 25. degree. C. The polymers of this invention exhibit many of the advantageous properties of both polybenzimidazole and polybenzimidazolone polymers. They are characterized as being extremely resistant to chemical attack such as by solvents, acids and bases.

US Patent:

50773836, Dec 31, 1991

Filed:

Mar 15, 1990

Appl. No.:

7/494009

Inventors:

Rohitkumar H. Vora - Westfield NJ
Paul N. Chen - Gillette NJ
Joseph D. Menczel - Passaic NJ

Assignee:

Hoechst Celanese Corp. - Somerville NJ

International Classification:

C08G 6942
C08G 6926
C08G 802
C08G 6300

US Classification:

528353

Abstract:

New polybenzimidazolone polymers produced from the reaction of an aromatic tetraamine with a hexafluoro dianhydride. These hexafluoro polybenzimidazolone polymers based on an aromatic hexafluoro dianhydrides show improved solubility, easy processability, low moisture uptake, high thermal stability, resistance to solvent and other improvements over conventional polybenzimidazolone polymers.

US Patent:

50250892, Jun 18, 1991

Filed:

Nov 13, 1989

Appl. No.:

7/434148

Inventors:

Rohitkumar H. Vora - Westfield NJ
Paul N. Chen - Gillette NJ

Assignee:

Hoechst Celanese Corp. - Somerville NJ

International Classification:

C08G 6926

US Classification:

528353

Abstract:

Copolyimides derived from the reaction product of 3,3'-6 F diamine or 4,4'-6 F diamine, at least one other diamine, and pyromellitic dianhydride can be rendered solvent soluble while at the same time exhibiting an improvement in both mechanical and electrical properties by the inclusion of at least one other dianhydride having a diaryl nucleus in the reaction media. Suitable such dianhydrides include bis (3,4 dicarboxy phenyl) ether dianhydride, 3,3'4,4' benzophenone tetracarboxylic dianhydride, 3,3',4,4' diphenyl tetracarboxylic acid dianhydride and 2,2 bis(3,4 dicarboxyphenyl) hexafluoropropane dianhydride (6F-DA). Such polyimides are soluble in common organic solvents such as methyl ethyl ketone or N-methyl pyrrolidone, and exhibit excellent film forming properties with improved mechanical and electrical properties as compared to the corresponding homopolyimides. They possess excellent heat stability (Tg's in excess of about 350. degree. C. ) and have superior electrical properties, for example, dielectric constant of less than about 2.