Patents Represented by Law Firm Lynch, Cox & Gilman
  • Process for the production of molded polybenzimidazole articles and the resultant articles
    Patent number: 4717619
    Abstract: Disclosed herein is a process for the production of shaped polybenzimidazole articles which comprises forming a solvent solution of the polymer, depositing the solution on a support to form a film, removing sufficient solvent from the deposited film such that the film contains from about 10 to about 30 percent by weight of said solvent and compression molding the resulting product into a shaped article. Thus, this invention provides a unique process for the forming of molded shaped articles from polybenzimidazole based polymers.
    Type: Grant
    Filed: October 29, 1985
    Date of Patent: January 5, 1988
    Assignee: Hoechst Celanese Corporation
    Inventor: John S. Letinski
  • Method for the preparation of polybenzimidazole membranes
    Patent number: 4693825
    Abstract: This invention is an improved process for the preparation of polybenzimidazole membranes. When benzyl alcohol is added to a polybenzimidazole casting dope, polybenzimidazole membranes useful in reverse osmosis may be prepared without annealing the membrane.
    Type: Grant
    Filed: September 23, 1985
    Date of Patent: September 15, 1987
    Assignee: Celanese Corporation
    Inventor: Norman S. Trouw
  • Process for the production of polybenzimidazole ultrafiltration membranes
    Patent number: 4693824
    Abstract: This invention relates to the preparation of ultrafiltration polybenzimidazole membranes in a coagulation bath comprised of a solvent and a non-solvent for the polybenzimidazole.
    Type: Grant
    Filed: September 23, 1985
    Date of Patent: September 15, 1987
    Assignee: Celanese Corporation
    Inventor: Michael J. Sansone
  • Process for the preparation of polybenzimidazole foams
    Patent number: 4681716
    Abstract: The present invention is a process for the preparation of polybenzimidazole foams. Polybenzimidazoles containing 10 to 30 percent by weight residual solvent can be heated at a temperature of about 350.degree. C. to about 600.degree. C. to produce three dimensional foamed articles.
    Type: Grant
    Filed: March 3, 1986
    Date of Patent: July 21, 1987
    Assignee: Celanese Corporation
    Inventor: John S. Letinski
  • Crosslinking of polybenzimidazole polymer with divinyl sulfone
    Patent number: 4666996
    Abstract: Disclosed herein is a process for crosslinking polybenzimidazole polymers which comprise reacting said polymers with a divinylsulfone in the presence of a strong base catalyst.
    Type: Grant
    Filed: January 24, 1986
    Date of Patent: May 19, 1987
    Assignee: Celanese Corporation
    Inventor: Michael J. Sansone