Patents by Inventor Edwardo Alvarez

Edwardo Alvarez has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Self lubricating polybenzimidazole shaped articles
    Patent number: 5384352
    Abstract: A compactible polybenzimidazole composition contains from about 95 to about 5 weight percent of solid lubricant particles which are uniformly dispersed and encapsulated in from about 55 to about 95 weight percent of polybenzimidazole. The solid lubricant comprises graphite and boron nitride in a weight ratio of about 10:1 to about 1:10. The composition is useful for preparing self lubricating, shaped articles such as bearings, bearing sleeves, rings, seals, etc. which exhibit low friction properties.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: January 24, 1995
    Assignee: Hoechst Celanese Corp.
    Inventors: Todd E. Andres, Edwardo Alvarez, William M. Cooper, O. Richard Hughes, Wendell G. Whiteside
  • Process for pressure sintering polymeric compositions
    Patent number: 5167889
    Abstract: A process for heat treating polymeric compositions into a shaped article comprising the steps of:a. placing a polymeric composition into a molding means;b. adding a compactible material to the molding means to surround the polymeric composition;c. pressuring the molding means containing the polymeric composition to force its particles into intimate contact with the compactible material, and clamping the molding means so as to maintain the pressurized state;d. heat treating the pressurized molding means containing the polymeric composition to form a densified, shaped article; ande. releasing the pressure on the molding means and removing the heat treated, shaped article.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: December 1, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Edwardo Alvarez, Todd E. Andres
  • Molded polybenzimidazole/polyaryleneketone articles and method of manufacture
    Patent number: 5139863
    Abstract: Molded article having improved thermal resistance and strength formed from a homogeneous mixture comprising from about 5 to 75 percent by weight polybenzimidazole and from about 95 to 25 percent by weight of a polyaryleneketone. These articles are obtained by injection molding techniques.
    Type: Grant
    Filed: August 22, 1991
    Date of Patent: August 18, 1992
    Assignee: Hoechst Celanese Corporation
    Inventors: Edwardo Alvarez, Lorenzo P. DiSano, Bennett C. Ward
  • Molded polybenzimidazole/polyaryleneketone articles and method of manufacture
    Patent number: 5070153
    Abstract: Molded article having improved thermal resistance and strength formed from a homogeneous mixture comprising from about 5 to 75 percent by weight polybenzimidazole and from about 95 to 25 percent by weight of a polyaryleneketone. These articles are obtained by injection molding techniques.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: December 3, 1991
    Assignee: Hoechst Celanese Corporation
    Inventors: Edwardo Alvarez, Lorenzo P. DiSano, Bennett C. Ward
  • Sintered polybenzimidazole/polyaryleneketone articles and method of manufacture
    Patent number: 4912176
    Abstract: Sinterd molded article having improved thermal resistance and strength formed from a homogeneous mixture comprising from about 5 to 75 percent by weight polybenzimidazole and from about 95 to 25 percent by weight of a polyaryleneketone.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: March 27, 1990
    Assignee: Hoechst Celanese Corporation
    Inventors: Edwardo Alvarez, Lorenzo P. DiSano, Bennett C. Ward
  • Process of making a sintered polybenzimidazole article
    Patent number: 4861537
    Abstract: Sintered polybenzimidazole articles are obtained by compacting a particulate, dried polybenzimidazole resin under a pressure of 2,000 to 10,000 psi in a mold, heating the formed article to a temperature in the range of 825.degree. to 950.degree. F. for at least four hours, cooling the polybenzimidazole article to below 800.degree. F. while maintaining the article under a pressure of 2,000 to 10,000 psi, and thereafter heating the constrained formed polybenzimidazole article to a temperature in the range of 825.degree. to 950.degree. F. for at least one hour.
    Type: Grant
    Filed: July 25, 1988
    Date of Patent: August 29, 1989
    Assignee: Hoechst Celanese Corporation
    Inventors: Bennett C. Ward, Edwardo Alvarez, Ralph S. Blake
  • Sintered polybenzimidazole article
    Patent number: 4814530
    Abstract: Sintered polybenzimidazole articles are obtained by compacting a particulate, dried polybenzimidazole resin under a pressure of 2,000 to 10,000 psi in a mold, heating the formed article to a temperature in the range of 825.degree. to 950.degree. F. for at least four hours, cooling the polybenzimidazole article to below 800.degree. F. while maintaining the article under a pressure of 2,000 to 10,000 psi, and thereafter heating the constrained formed polybenzimidazole article to a temperature in the range of 825.degree. to 950.degree. F. for at least one hour.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: March 21, 1989
    Assignees: Hoechst Celanese Corporation, Alpha Precision Plastics, Inc.
    Inventors: Bennett C. Ward, Edwardo Alvarez, Ralph S. Blake