Abstract: High compressive strength, three-dimensional para-oriented benzobisoxazole polymers of the formula: ##STR1## wherein Q is ##STR2## and wherein Z represents repeating units of the formula: ##STR3##

Abstract: A two-dimensional, rigid-rod polymer of the formula: ##STR1## wherein x, y and z each has a value of 5 to 40; wherein the sum of x, y and z is about 20 to 100; and wherein PBX is a repeating group of the formula: ##STR2## is prepared by the polycondensation of trimeric acid (TMA) ##STR3## with 4-[5-amino-6-hydroxybenzoxazol-2-yl]benzoic acid (ABA) ##STR4## in polyphosphoric acid (PPA).

Abstract: There are provided fusible, rod-like graft copolymers having repeating units of the formula: ##STR1## wherein a ranges from about 0.75 to 0.97 and b is 1-a; wherein Z is a benzbisoxazole or benzbisthiazole moiety, wherein Ar is a linear phenylene or polyphenylene moiety, wherein Ar' is ##STR2## and wherein Y is a poly(etherketone) or a poly(etheretherketone), wherein the poly(etherketone) has repeating units of the formula ##STR3## wherein Q is a divalent phenylene or substituted phenylene moiety and c is an integer having a value of 1 to 4, and the poly(etheretherketone) has repeating units of the formula ##STR4## wherein Q' is a divalent phenylene or substituted phenylene moiety, d is an integer having a value of 1 to 4 and e is an integer having a value of 2 to 5.Also provided are methods for making these graft copolymers.

Abstract: Benzobisthiazole polymers with thiophene moieties having repeating units of the formula:--Bt--(--Tp--).sub.n --wherein Bt is ##STR1## Tp is ##STR2## and n has a value of 1 to 3.

Abstract: Fusible, rod-like, graft polymers and copolymers having repeating units of the formula: ##STR1## wherein x ranges from 0 to about 0.97, y is 1-x, Y is a poly(etherketone) (PEK) or a poly(etheretherketone) (PEEK), and wherein Ba is a benzobisimidazole or benzobisthiazole moiety are provided.Also provided are methods for preparing the above polymers and copolymers, 2-(2,6-dimethylphenoxy)terephthalic acid and a method for preparing the latter.

Abstract: There is provided a para-ordered, rigid-rod aromatic heterocyclic copolymer having repeating groups of the formula:--Ba--Ar).sub.x (Ba--Fl).sub.1.0-xwherein x has a value of 0.50 to 0.99, Fl is a 2,7-fluorene moiety, Ar is a para-ordered arylene group and Ba is a benzazole group of the formula: ##STR1## wherein Y is S or O.

Abstract: A fusible, rod-like, graft copolymer having repeating units of the formula: ##STR1## wherein X is (--CH.sub.2 CH.sub.2 CONH--).sub.m or (--CH.sub.2 --CH(CH.sub.3)--O--).sub.n, wherein m has an average value of 5.0 to 35.0 and n has an average value of 1.0 to 30.0.

Abstract: There is provided an aromatic polyamide having repeating units of the formula: ##STR1## wherein X is -O-, -S-, -CO- or -SO.sub.2 - and y has a value of 1 or 2. Also provided is an aromatic polyamide having repeating units of the formula: ##STR2## and a new composition of matter 3-[4-(3-aminophenoxy benzoyl)phenoxy] benzoic acid.

Abstract: Provided is an acetylene-terminated aromatic amide compound of the formula ##STR1## wherein X is --O-- or --S--, Z is --O--, --S--, --SO.sub.2 --, or --CO--, and R is --H or --C.tbd.CH in the ortho, meta or para position, wherein at least one R is --.tbd.CH.

Abstract: Aromatic polyamide resins having repeating units, each containing at least one m-ethynyl amido subunit: ##STR1## These resins can be thermally treated to undergo intra-molecular cyclization, without evolution of volatiles, into polyimidines containing the following subunit.

Abstract: Aromatic polyamide resins having repeating units, each containing at least one m-ethynyl amido subunit: ##STR1## These resins can be thermally treated to undergo intra-molecular cyclization, without evolution of volatiles, into polyimidines containing the following subunit.

Abstract: Aromatic monomers, each containing at least one o-ethynyl carboxylic acid halide subunit: ##STR1## wherein X is Cl or Br. These monomers can be reacted with amines to form aromatic polyamide resins which can be thermally treated to undergo intromolecular cyclization, without evolution of volatiles, into polyimidines.

Abstract: Articulated p-benzobisoxazole and p-benzobisthiazole polymers which contain a limited number of 3,3'-biphenyl or 2,2'-bipyridyl segments are synthesized, with inherent viscosities as high as 14 dl/g being recorded. The 3,3'-biphenyl or 2,2'-bipyridyl segments in the p-benzobisoxazole and p-benzobisthiazole polymers impart flexibility to the polymers without adversely affecting the thermooxidative stability. While the resultant articulated polymers exhibit liquid crystalline behavior in methanesulfonic acid and form strong cast films from that solvent, they also exhibit thermooxidative stability comparable to other p-benzobisthiazole and p-benzobisoxazole polymers. The resultant films are useful for the fabrication of high strength laminates to be used in severe environment structural applications.

Abstract: Para-ordered aromatic heterocyclic polymers characterized by having p-benzbisoxazole, p-benzbisthiozole or p-benzbisimidazole units and containing diphenoxybenzene structures. The diphenoxybenzene structures function as "swivels" in the polymer chains, imparting flexibility thereto and making it possible to cast strong films from solutions of the polymers.

Abstract: 2-Amino-4-ethynylphenol, a novel compound, is prepared by a four-step synthetic sequence in which the key reaction is the treatment of 4-acetoxy-3-nitroacetophenone with a Vilsmeier reagent derived from N,N-dimethylformamide and phosphorus oxychloride. The compound is useful as an endcapping agent in the synthesis of fluorocarbon ether bibenzoxazole oligomers which, because of the presence of acetylenic terminal groups, can be cured by thermal means to provide broad-use temperature, fuel and fluid resistant vulcanizates.

Abstract: Fluorocarbon ether bibenzoxazole oligomers having reactive terminal acetylenic groups which make it possible to thermally cure the oligomers without the evolution of volatiles to rubbery vulcanizates exhibiting high thermooxidative stability and low temperature flexibility, properties that render the materials suitable for various aerospace applications such as for seals and sealants.

Abstract: Thermooxidatively and hydrolytically stable perfluoroalkylene ether bibenzoxazole polymers containing hydrocarbon cure sites are synthesized by the polycondensation of a fluorocarbon bis(o-aminophenol) containing a hydrocarbon moiety and a perfluoroalkylene ether diimidate or dithioimidate ester. The polymers are readily curable to elastomers that are resistant to hydrolysis over a wide use-temperature range. Thus, the polymers are especially suitable for use in aerospace applications where extreme environments are encountered. In particular, the polymers are useful as seals, sealants, and the like.

Abstract: Fluorocarbon bis(o-aminophenol) compounds in which fluoroalkylene groups attached to each aminophenol radical are separated by a hydrocarbon moiety. The compounds are useful as monomers in preparing thermooxidatively and hydrolytically stable, low glass transition temperature perfluoroalkylene ether bibenzoxazole polymers containing hydrocarbon cure sites.

Abstract: Thermooxidatively and hydrolytically stable perfluoroalkylene ether bibenzoxazole polymers having improved viscoelastic properties are synthesized by the polycondensation of perfluoroalkylene ether bis(o-aminophenol) compounds with thioimidate esters derived primarily from tetrafluoroethylene oxide but end-capped with hexafluoropropylene oxide. Based on their lower glass transition temperature, the polymers have a very broad use temperature range which renders them particularly useful under severe environmental conditions encountered in aerospace elastomer applications such as seals and sealants.

Abstract: Perfluoroalkylene ether thioimidate esters derived primarily from tetrafluoroethylene oxide but end-capped with hexafluoropropylene oxide in the terminal positions of the perfluoroalkylene ether chain. The compounds are particularly useful as monomers to synthesize novel thermooxidatively and hydrolytically stable perfluoroalkylene ether bibenzozazole polymers having improved low temperature viscoelastic properties.