Abstract: A process for preparing halogen-terminated oligomers by an Ullmann condensation is disclosed wherein a diphenol and a dihalobenzene are reacted in the presence of cuprous oxide in 2,4,6-collidine. The oligomers are useful in producing acetylene-terminated resins by replacing the terminal halogen atoms with acetylene groups.

Abstract: Difunctional aromatic enyne compounds are prepared by the catalytic coupling of substituted monoethynyl compounds. The compounds are useful as monomers in polycondensation reactions for the preparation of high molecular weight, thermally stable thermoplastic polymers. On thermal treatment of the polymers, the enyne groups along the polymer backbones react by interchain reactions to provide the solvent and craze resistance required for application as structural materials.

Abstract: As new compositions of matter, ethynyl-substituted aromatic `peri` anhydrides. The compounds are useful as endcapping agents for thermally stable heterocyclic imide compositions.

Abstract: Acetylene-terminated quinoxaline compositions are prepared by reacting an aromatic bisbenzil with an excess of a bis(o-diamine) to provide an ortho-diamino endcapped quinoxaline oligomer which is then converted to the acetylene endcapped composition by reacting with an acetylenic benzil.

Abstract: As new compositions of matter, acetylene-substituted aromatic benzils. The benzils are particularly useful in the synthesis of acetylene-terminated quinoxaline compositions which cure by nonvolatile addition reactions.

Abstract: As new compositions of matter, ethynyl-substituted aromatic `peri` anhydrides. The compounds are useful as endcapping agents for thermally stable heterocyclic imide compositions.

Abstract: Thermally stable, highly fused imide polymers are prepared by reacting 2,2'-bis(phenylethynyl)-4,4'-diaminobiphenyl or 2,2'-bis-(phenylethynyl)-5,5'-diaminobiphenyl with an aromatic dianhydride. The polyimides are particularly suitable for use in high temperature applications, such as in the fabrication of fiber reinforced structural composites, fibrous materials and protective coatings.

Abstract: As new compositions of matter, 2,2'-bis(phenylethynyl)-4,4'-diaminobiphenyl and 2,2'-bis(phenylethynyl)-5,5'-diaminobiphenyl. The compounds are useful as monomers suitable for the preparation of thermally stable polymer systems such as polyimides, polyamides and poly-Schiff bases.

Abstract: Quinoxaline polymers are synthesized by solution polycondensation of 2,2'-bis(phenylethynyl)-5,5'-diaminobenzidine with aromatic bis-benzils. Upon heating the polymers so prepared at a temperature ranging from about 240.degree. to 300.degree.C, they undergo a thermal intramolecular cyclization reaction, thereby providing cured, thermally stable, highly fused quinoxaline composition. Because of their solubility in aprotic solvents and the mechanism whereby they are cured, the quinoxaline polymers are particularly suitable for use in high temperature applications such as in the fabrication of plastic composites and protective coatings.