Abstract: A method for producing polymeric, e.g., polybenzimidazole (PBI) films, is provided by forming a porous membrane by coagulating a polymeric dope solution in a liquid coagulation bath containing a non-solvent alone or a mixture of a non-solvent and solvent; submerging the resulting membrane into a non-solvent bath to remove any residual solvent; placing the membrane into an acid solution, whereby the pores become filled with the acid solution; and drying the membrane to remove residual non-solvent which collapses the porous structure entrapping the acid and forming a dense film. An alternative method involves coagulating said polymer solution directly into an acid/solvent/non-solvent mixture to produce a porous membrane which imbibes the acid solution, followed by drying.

Abstract: A method for producing polybenzimidazole (PBI) fabrics for use as fuel cell or battery electrolytes by soaking a sulfonated or non-sulfonated PBI fabric in an acid solution, whereby the fibers of the fabric become swollen with the acid solution; and drying the fabric to remove residual water or methanol and concentrating the acid.

Abstract: A method for producing polybenzimidazole (PBI) paste or gel useful in a fuel cell, mixing PBI polymer with a suitable amount of an acid, which permits the polymer to dissolve and form a matrix having a gel-like or paste-like consistency at room temperature.

Abstract: A polypropylene or polyethylene film or fiber coated with a maleic-acid grafted polypropylene or polyethylene copolymer layer over which is coated a layer of selective polymer. The copolymer securely bonds the selective polymer to the film or fiber. These fibers and films can be used in fluid separation membranes.

Abstract: An electrolytic membrane for use in fuel cell includes a fluid-imbibed acidified polybenzimidazole resin. The resin is alkyl or aryl sulfonated or alkyl or aryl phosphonated, preferably with a degree of substitution of from 15 to about 60 per cent.

Abstract: This invention provides superior electrooptic devices containing an organic polymeric waveguiding medium, and a process of fabricating such devices. The fabrication process utilizes a substantially stress-free organic polymeric substrate on top of which the necessary organic layers are successively deposited. The substrate is so selected that its thermal expansion coefficient is substantially close to that of the cladding layers and of the waveguiding layer.

Abstract: Provided is an optical information medium comprised of an organic information layer and a resinous continuous film overcoat layer which is coated over said organic information layer. The resinous overcoat layer is no thicker than, and most preferably thinner than said information layer, and is of a thickness of about 100 angstroms or less. It is most preferred that the overcoat layer is comprised of a water soluble polymer. The resulting optical information medium advantageously exhibits an extremely sharp threshold for marking, as well as improved carrier to noise ratio.

Abstract: Provided is a method for preparing an optical information medium which comprises a polycarbonate substrate. A polycarbonate substrate is subjected to an aqueous ammonia solution treatment at a temperature below ambient temperatures and for an extended period of time. This treatment occurs prior to assembly of the optical information medium. Use of the treated polycarbonate substrate in the optical information medium results in the medium exhibiting a high level of performance over an extended useful life.

Abstract: Provided is a method for stabilizing an optical information medium by incorporating an effective amount of a specific nitrogen containing compound into the medium. The specific nitrogen containing compounds are poly(2-vinyl pyridine), poly(4-vinyl pyridine), pentaethylene hexamine and acridine orange base. Incorporation of one of the nitrogen compounds into the optical information medium prolongs the useful life of the medium.

Abstract: Provided is an optical information card having a particular structure. The card is comprised of four different layers, i.e., a card substrate, a recording layer which is formed on one side of the card substrate and which comprises a naphthalocyanine compound, a polyvinyl alcohol coating directly over the information layer, and a transparent protective layer over the polyvinyl alcohol layer. This structure offers a very sensitive and useful optical information card which can be easily manufactured while maintaining the integrity of the information layer, and which permits one to realize the advantage of using a naphthalocyanine information layer in a card format.

Abstract: A process for sulfonating preformed hydroxyethylated polybenzimidazole fibers is disclosed. The process comprises the steps of forming an hydroxyethylated polybenzimidazole spinning solution; spinning hydroxyethylated polybenzimidazole fibers, sulfonating the fibers by contacting them with a sulfonating agent, and heating the fiber in an inert atmosphere at a temperature and for a period of time sufficient to convert the ionic bonds, formed in the sulfonating step to covalent bonds, thereby, providing a covalently bonded, sulfonated, hydroxyethylated polybenzimidazole fiber. The fibers produced by the process of the present invention exhibit cation selectivity for electrodialysis and electrochemical applications.

Abstract: Hydroxyethylated polybenzimidazole fibers are produced by a wet jet/wet spinning or by a dry jet/wet spinning process. A spinning solution of hydroxyethylated polybenzimidazole is extruded vertically downward through a spinneret into a liquid coagulation bath. The resulting fibers have pore sizes ranging from about 5 angstroms up to about 100 angstroms and are quite useful as ultra filters for molecules with a broad range of molecular weight.