Abstract: Polyetherketoneimides and copolymers thereof having an imide repeat unit of formula ##STR1## wherein Ri is ##STR2## in which A is a direct bond or --O--or another substantially non-electron-withdrawing group, and/or Ra is an at least partly arylene moiety other than m- or P-phonylene.These polymers tend to have improved melt stability and other properties, especially when made from a pre-existing imide monomer, instead of by the known amic acid route which results in uncyclised amic acid residues in the polymer.

Abstract: A polyimide film essentially consisting of polyimide having recurring units of the formula (I): ##STR1## which has a density of 1.335 to 1.390 g/cm.sup.3 at 23.degree. C. and/or a refractive index of 1.605 to 1.680 at 23.degree. C. in the direction of thickness and is transparent; and a preparation process of the polyimide film by extruding the polyimide having recurring units of the above formula (I) through a common melt-extrusion process, casting in a chill-roller to obtain an unstretched film, uniaxially or biaxially stretching the unstretched film to cause molecular orientation, and successively setting the stretched film through heat-treatment.

Abstract: A heat-resistant and thermoplastic polyimide which has low dielectric characteristics and recurring structural units of the following formula ##STR1## wherein R is a tetravalent radical having from 2 to 27 carbon atoms and selected from the group consisting of an aliphatic radical, alicyclic radical, monoaromatic radical, condensed polyaromatic radical and noncondensed aromatic radical connected each other with a direct bond or a bridge member; aromatic diamines which are useful for the raw material monomers of the polyimide and have following formulas: ##STR2## and ##STR3## and a process for preparing the polyimide of the above formula by reacting these aromatic diamines with a tetracarboxylic dianhydride in the presence of an aromatic dicarboxylic anhydride or aromatic monoamine, and successively thermally or chemically imidizing the resultant polyamic acid.

Abstract: An aromatic polyimide film coated with a thermally stable, heat-sealable thermoplastic polyimide for use as a wire insulation for superconducting magnets is disclosed. The inclusion of inorganic particles in the film improves compressive strength of the coated polyimide film.

Abstract: The present polyamido-acid copolymer has a polymerization backbone chain represented by the following formula: ##STR1## wherein q represents a bivalent organic group and R represents a tetravalent aromatic group. This copolymer forms a polyimide resin film excellent in adhesion to various inorganic substances and mechanical strength.

Abstract: Curing of phthalonitrile monomers and prepolymers is accelerated by inclusion of an acid curing agent. Cured phthalonitrile polymers have high thermal oxidative stability and are useful as resins in various compositions and as adhesives.

Abstract: A new class of polymers is provided as well as the monomers used for their preparation. The polymers provided in accordance with practice of the present invention include repeating units comprising one or more quinoline groups, wherein at least a portion of the repeating units includes a hexafluoroisopropylidene (6F) group or a 1-aryl-2,2,2-trifluoroethylidene (3F) group, or both.The hexafluoroisopropylidene group is referred to herein as a "6F" group and has the following structure: ##STR1## The "6F" group includes a tetravalent carbon atom bound to two trifluoromethyl moieties with its other two bonds forming linkages in the polymer chain.the 1-aryl-2,2,2-trifluoroethylidene group is referred to herein as "3F" group and has the following structure: ##STR2## wherein Ar' is an aryl group. The "3F" group comprises a tetravalent carbon atom bound to one trifluoromethyl moiety and one aryl group with its other two bonds forming linkages in the polymer chain.

Abstract: A polymer which can undergo thermally-induced transformation to provide a reinforcing component and a matrix component. This polymer has repeating units of the formula: ##STR1## wherein Z is selected from the group consisting of dialkyl amino thermoplastic moieties and dialkyl amino moieties which can undergo insitu reaction to form a thermoset. Dialkyl amino moieties which can undergo insitu reaction to form thermosets include the following: ##STR2## wherein Q is ##STR3## R is --CH.sub.3 or Q and a has a value of 1 to 3. Dialkyl amino thermoplastic moieties include the following: ##STR4##The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.

Abstract: The present invention relates to aminoarylsulfonic acid-phenol-formaldehyde condensate useful for incorporation into cementing compositions, for example, mortar, cement paste and the like, for improving slumping characteristics.

Abstract: 1. A polyamide molding compound, comprised of:(I) an aromatic polyamide having the structure ##STR1## where n is a number between 5 and 500; X represents --SO.sub.2 -- or --CO--, andY represents --O-- or --S--; and (II) an amorphous polyamide.

Abstract: Disclosed is a polyimide ammonium salt comprising the reaction product of an ethylenically unsaturated amine with an aromatic polyimide having pendant carboxylic acid groups, said polyimide comprising the reaction product of diamine and aromatic dianhydride, where the diamine comprises an aromatic carboxylic acid diamine having at least one carboxylic acid. A substrate can be coated with the polyimide ammonium salt by forming a composition of a crosslinking agent and a solution of the polyimide salt in an organic solvent, spreading the composition on the substrate, evaporating the solvent to form a coating, exposing at least some of the coating to actinic radiation to crosslink and insolubilize the exposed portions of the coating, and washing the unexposed portions away by dissolving them in an organic solvent.

Abstract: The terminal-modified imide oligomer composition capable of being cured within a short time and of being converted to a shaped, cured resin article having a high mechanical strength, heat resistance and elastic modulus, comprises a rigid, high molecular weight aromatic polyimide (I) produced by polymerizing and imidizing a tetracarboxylic acid component comprising at least one biphenyltetracarboxylic acid compound with an amine component comprising at least one aromatic diamine compound (a) having at least one cyclic structure and two amino groups directly attached to the cyclic structure; a flexible imide oligomer (II) produced by polymerizing and imidizing the tetracarboxylic acid component, with a diamine component comprising at least one aromatic diamine compound (b) having at least two cyclic structures and two amino groups attached directly or through a divalent bonding member to the cyclic structures and a monoamine component comprising at least one monoamine compound (c) having an unsaturated hydrocar

Abstract: Poly(dianhydride) compounds having formulae (I) and (II): ##STR1## where m is 0 to 50. ##STR2## wherein n is 0 to 20 and X is bond junction, oxygen atom, sulfur atom, SO.sub.2, C(CF.sub.3), CO, C(CH.sub.3).sub.2, CF.sub.2 --O--CF.sub.2, CH.sub.2, and CHOH.

Abstract: Sizing for carbon fibers with uncapped or capped linear polyamideimides.The uncapped linear polyamideimides useful as carbon fiber sizings generally contain repeating units having the general formula: ##STR1## Wherein R.sub.2 =a trivalent organic radical and generally benzenetriyl;R.sub.3 =a divalent organic radical; andn=an integer sufficiently large to provide a strong, tough coating.Useful capped, linear polyamideimide oligomers may be formed by including end caps with an unsaturated functionality (Y) containing a residue selected from the group consisting of: ##STR2## wherein R.sub.1 =lower alkoxy, aryl, aryloxy, substituted alkyl, substituted aryl, halogen, or mixtures thereof;j=0, 1, or 2;i=1 or 2;G=--CH.sub.2 --, --O--, --S--, --SO.sub.2 --, --SO--, --CO--, --CHR--, or --CR.sub.2 --;T=methallyl or allyl;Me=methyl; andR=hydrogen, lower alkyl, or phenyl.Prepregs and composites having carbon fibers sized with such polyamideimides are also described.

Abstract: Polyimide sheets having excellent thermal resistance and good surface appearance of the resultant sheets are obtained by a melt-extrusion process from a specific polyimide in the temperature range of 300.degree. C. to 450.degree. C. and a moisture content of 200 ppm or less.

Abstract: Polymerization or cure of di-phthalonitrile monomers or prepolymers by a curing agent selected from (a) an acid and an amine, (b) a salt of an acid and an amine, and (c) mixtures of (a) and (b). In a preferred embodiment, the curing agents are amine salts which are reaction products of an aromatic amine and an aromatic sulfonic acid. The use of the novel curing agents enhances curing rates and results in polymers which have high Tg.

Abstract: A perfluorinated polyimide comprising a repeating unit represented by general formula (1): ##STR1## and a perfluorinated poly(amic acid) comprising a repeating unit represented by general formula (6): ##STR2## wherein R.sub.1 is a tetravalent organic group; and R.sub.2 is a divalent organic group, provided that chemical bonds between carbon atoms and monovalent elements contained in R.sub.1 and R.sub.2 are exclusively carbon-to-fluorine bonds; methods for preparing them; and optical material including the perfluorinated polyimide. 1,4-Bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene dianhydride, 1,4-difluoropyromellitic anhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene, 1,4-difluoropyromellitic acid, and 1,4-bis(3,4-dicyanotrifluorophenoxy)tetrafluorobenzene as well as methods preparing them. The perfluorinated polyimide has a thermal stability and has a low optical loss in an optical communication wavelength region (0.8 to 1.7 .mu.m).

Abstract: A novel aromatic diamine; a polyimide comprising 1,3-bis(3-aminobenzoyl)benzene or 4,4'-bis(3-aminobenzoyl)biphenyl as a diamine component and having recurring structural units represented by the formula (III): ##STR1## wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having from 2 to 27 carbon atoms, alicyclic radical, monoaromatic radical, condensed polyaromatic radical, and noncondensed aromatic radical connected each other with a direct bond or a bridge member, and X is a divalent radical of ##STR2## and a polyimide having a terminal aromatic group which is essentially unsubstituted or substituted with a radical having no reactivity with amines or dicarboxylic acid anhydrides or a composition comprising said polyimide.

Abstract: A polyamic acid having a three-dimensional network molecular structure produced by a gel forming ring-opening polyaddition reaction in an organic solvent of the reaction components comprising:(A) an acid component consisting of at least one tetracarboxylic acid dianhydride selected from the group consisting of a tetracarboxy benzene dianhydride, a tetracarboxy dianhydride of a compound having 2 to 5 condensed benzene rings, and compounds represented by formula (III), and substituted compounds thereof: ##STR1## wherein R.sub.1 represents --O--, --CO--, --SO.sub.2 --, --SO--, an alkylene group, an alkylene bicarbonyloxy group, an alkylene bioxycarbonyl group, a phenylene group, a phenylene alkylene group, or a phenylene dialkylene group, n.sub.4 is 0 or 1, n.sub.5 is 0 or 1; and n.sub.6 is 1 or 2, provided that the sum of n.sub.5 and n.sub.

Abstract: Aromatic polyether polymers, illustrated by polyethersulfones, polyetherketones and polyetherimides, are prepared by a phase transfer catalyzed reaction between a salt of a dihydroxyaromatic compound and a substituted aromatic compound such as bis(4-hydroxyphenyl) sulfone, bis(4-hydroxyphenyl) ketone or 1,3-bis[N-(4-chlorophthalimido)]benzene or the corresponding derivative of toluene or diphenyl ether, or the analagous fluoro-, bromo- or nitro-substituted compounds. The phase transfer catalysts employed are those which are stable at temperatures in the range of about 125.degree.-250.degree. C. Particularly preferred phase transfer catalysts are the hexaalkylguanidinium and .alpha.,.omega.-bis(pentaalkylguanidinium)alkane salts and the corresponding heterocyclic salts.

Abstract: The invention relates to soluble homo- or copolyimides of formula I ##STR1## wherein Y is hydrogen or the substituents Y, together with the linking N atom, are a divalent radical of of formulae IIa to IIc ##STR2## and X is the radical of of an aromatic amine after removal of the amino end groups, and n is an integer from 5 to 150.The compounds of the invention are readily soluble in organic solvents and are suitable tougheners for epoxy, bismaleimide and triazine resin systems.

Abstract: Soluble and/or meltable benzothiazole-containing polyaryl ethers with a glass transition temperature of above 150.degree. C. and a melting point of up to 450.degree. C. are composed essentially of repeat units of the formula I ##STR1## whose rings may be substituted by C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.

Abstract: High performance composites can be made from linear or multidimensional oligomer or blends that include unsaturated hydrocarbon crosslinking functionalities linked to a benzenetriyl or pyrimidine radical on the terminal ends of the polymeric backbones of the oligomers. The oligomers are made by condensing benzenetriyl or pyrimidine-based end-cap monomers of the formulas: ##STR1## wherein R.sub.1 =lower alkyl, lower alkoxy, aryl, aryloxy, substituted alkyl, substituted aryl, halogen, or mixtures thereof;j=0, 1, or 2;G=--CH.sub.2 --, --O--, --S--, --SO--, --CO--, --CHR--, --CR.sub.2 --, or --SO.sub.2 --;T=methallyl or allyl;Me=methyl;R=hydrogen, lower alkyl, or phenyl;Ph=phenyl; ##STR2## Q=--NH.sub.2, --COX, --NO.sub.2, or --COOH, with suitable polymeric precursors.

Abstract: Premix for the production of mouldings, containingA) from 40-99.95% by weight of polymer granules A based on a polyaryl ether sulfone, polyaryl ether ketone, polyimide, polyamide imide or polyether imide, or a mixture thereof,B) up to 50% by weight of fillers B in fiber or particle form, or a mixture thereof,C) from 0.05-10% by weight of a compound C ether of the general formula X ##STR1## where A1 to A7 are identical or different and, independently of one another, are a radical of the formula --CO--, --O--, --S--, --SO.sub.2 --, --C(CH.sub.3).sub.2 --, a chemical bond, ##STR2## and k, l, m, n, p and q are each 0 or 1, or a C.sub.1 -C.sub.8 -alkyl, C.sub.1 -C.sub.8 -alkoxy or cyano derivative thereof which is substituted on the aromatic ring, or of the general formula Y ##STR3## where R is C.sub.1 -C.sub.8 -alkyl, C.sub.1 -C.sub.8 -alkoxy or cyano, A8 to A11 are as defined for A1 to A7, r, s and t are 0 or 1, and x is 2, 3 or 4, or a mixture thereof,is described.

Abstract: Polyimides having high glass transition temperature prepared from 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride and 1,5-, 1,6-, 2,6- or 2,7-bis(4-aminophenoxy)napthalene.

Abstract: The new aromatic polyethers containing ester groups, which are distinguished by high dimensional stability, may be used for the production of all kinds of moulded products as well as for the preparation of block copolymers of aromatic polyether segments and segments of other thermoplastic polymers.

Abstract: Tetrapolyimide films derived from oxydiphthalic dianhydride, pyromellitic acid dianhydride, p-phenylene diamine and 4,4'-diaminodiphenyl ether, and their preparation are described. The tetrapolymer films have low water absorption, low coefficients of thermal and hygroscopic expansion, high modulus and are caustic etchable and can be used in flexible printed circuit and tape automated bonding applications.

Abstract: A high-temperature stable, highly optically transparent-to-colorless, low dielectric linear aromatic polyimide is prepared by reacting an aromatic diamine with 3,3'bis(3,4-dicarboxyphenoxy)diphenylmethane dianhydride in an amide solvent to form a linear aromatic polyamic acid. This polyamic acid is then cyclized to form the corresponding polyimide, which has the following general structural formula: ##STR1## wherein Ar is any aromatic or substituted aromatic group, and n is 10-100.

Abstract: High performance, thermooxidatively stable polyimides are prepared by reacting aromatic diamines with pendant trifluoromethyl groups and dianhydrides in an amide solvent to form a poly(amic acid), followed by cyclizing the poly(amic acid) to form the corresponding polyimide, which has the following general structure: ##STR1##

Abstract: The solvent-resistance and thermal stability of polyamideimides of the general formulae: ##STR1## is improved by capping the amideimides with a crosslinking functionality (Y) containing a residue selected from the group of: ##STR2## wherein R.sub.1 =lower alkyl, lower alkoxy, aryl, aryloxy, substituted alkyl, substituted aryl (either including hydroxyl or halo-substituents), halogen, or mixtures thereof;j= 0, 1, or 2;G=--CH.sub.2 --, --O--, --S--, --SO.sub.2 --, --SO--, --CO--, --CHR--, or --CR.sub.2 --;R=hydrogen, lower alkyl, or phenyl;T=methallyl or allyl;Me=methyl;R.sub.2 =a trivalent organic radical; andR.sub.3 =a divalent organic radical.The amideimide oligomers may be linear or multidimensional, and can be processed into blends, prepregs, or composites. Methods of making these amideimides and intermediates useful in the syntheses are also described.

Abstract: Azole rings, such as oxazole and thiazole rings, can activate an aromatic ring bonded to a leaving group such as a halogen atom so that the aromatic ring will undergo aromatic nucleophilic substitution. The reaction is useful for making ethers, thioethers and amines containing azole rings. In particular, monomers having azole rings, activated aromatic rings with leaving groups and nucleophilic moieties can react under conditions of aromatic nucleophilic displacement to form non-rigid rod PBZ polymers. The non-rigid rod PBZ polymers can be used to form molecular composites with rigid rod PBZ polymers which molecular composites are not substantially phase separated.

Abstract: The semicrystalline polyimide prepared by reaction of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and 1,3-bis(4-aminophenoxy-4'-benzoyl)benzene (1,3-BABB) is modified so that it can be more readily processed to form adhesive bonds, moldings and composites. The stoichiometric ratio of the two monomers, BTDA and 1,3-BABB is controlled so that the intermediate polyamide acid is of a calculated molecular weight. A polyamide acid with excess anhydride groups is then reacted with the stoichiometrically required amount of monofunctional aromatic or aliphatic amine required for complete endcapping. A polyamide acid with excess amino groups is reacted with the stoichiometrically required amount of monofunctional aromatic anhydride required for complete endcapping. The stoichiometrically offset, endcapped polyimide is processed at lower temperatures and pressures than the unmodified high molecular weight polyimide with the same repeat unit, and exhibits an improved melt stability.

Abstract: Linear aromatic polyimides containing the cyclobutene-3,4-dione moiety were produced by reacting 1,2-bis(4-aminoanilino)cyclobutene-3,4-dione with several aromatic dianhydrides. The resulting polymers exhibited glass transition temperatures greater than 500.degree. C., adhered tenaciously to glass, and became more flexible after heating for 1 hour at 300.degree. C.

Abstract: A hot-melt adhesive comprising a special polyamideimide or polyamide is excellent in heat resistance and adhesive strength and usable for providing substrates for printed circuit boards.

Abstract: There are disclosed substantially linear polyarylene ether sulfones having a reduced viscosity of having a reduced viscosity of ca. 0.25 to ca. 1.5 dl/g (measured in a 1% solution in DMF at 25.degree. C.) and consisting essentially of 95-99.8% by weight of segments of formula I and of 5-0.2% by weight of segments of formula IIa, formula IIb and/or formula IIc ##STR1## the percentages by weight being based on the entire polymer and the molecular weight (number average) of the segments of formula I being 6000 to ca. 60 000, if the polymer contains solely structural units of formula IIa and/or IIb, and 1000 to ca. 60 000 if the polymer contains more than 0.1% by weight of structural units of formula IIc, and R consists of the recurring structural units of formula Ia and/or of up to 99.8% by weight, based on the total polymer, of recurring structural units of formula Ib ##STR2## wherein R.sub.1 is C.sub.1 -C.sub.6 alkyl, C.sub.3 -C.sub.10 alkenyl, phenyl or halogen, p is an integer from 0 to 4 Ar.sub.1 and Ar.

Abstract: In a process for the preparation of polyimide by reacting a diamine compound with tetracarboxylic dianhydride in a phenol based solvent, an improved process for reacting the diamine compound with tetracarboxylic dianhydride in a solution by forming separate solutions of the tetracarboxylic dianhydride and the diamine compound and mixing the solutions and/or by dissolving tetracarboxylic dianhydride in the phenol-based solvent containing an organic base.

Abstract: Integrated circuit sockets for use in a burn-in test are disclosed. The IC sockets are produced by injection molding of a specific polyimide having an inherent viscosity of 0.35 to 0.65 dl/g and essentially consisting of recurring units represented by the formula (I): ##STR1## wherein X is a radical selected from the group consisting of a bond, divalent hydrocarbon having from 1 to 10 carbon atoms, etc. and R is a tetravalent radical selected from the group consisting of an aliphatic radical having two or more carbon atoms, cycloaliphatic radical, monoaromatic radical etc.

Abstract: Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): ##STR1## wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5% or more, and fed to an extruder to obtain articles.

Abstract: A tri-component polyimide copolymer and the process of preparing the copolymer are disclosed. A mixed reaction medium or solvent system comprising phenol and at least one compound of resorcinol, 1,6-dimethyl phenol and 4-methoxy phenol is used to produce the copolymer by direct imidization without isolating or purifying the imide oligomer as an intermediate.

Abstract: Linear or multidimensional, crosslinking, solvent resistant oxazole, thiazole, or imidazole (i.e., heterocycle) oligomers and blends of the crosslinking oligomers and noncrosslinking comparable polymers are described. The oligomers are prepared by reacting tetraamines, diaminodiols, or diaminothiols (i.e. four-functional compounds) with poly-carboxylic acid halides, and crosslinking phenylimide end cap monomers in a suitable solvent under an inert atmosphere.

Abstract: A thermoplastically processable aromatic polyamide is prepared by polycondensing diacid monomer A with diamine monomer B: (A) HOOC--Ar--COOH;(B) H.sub.2 N--Ar'--NH.sub.2 ; wherein Ar is 1,3-- or 1,4-phenylene; 1,4--, 1,5--, 2,6-- or 2,7-naphthylene, ##STR1## and Ar' is ##STR2## wherein X is --SO.sub.2 -- or --CO--; Y is --O-- or --S--; Z is --O--, --S--, --SO.sub.2 --, --CO-- or ##STR3## wherein R and R' each is --H or C.sub.1 -- to C.sub.4 -alkyl and n is 0 or 1 in the melt at a temperature in the range of from 200.degree. to 400.degree. C. in the presence of a catalyst selected from the group consisting of alkyl- or aryl-phosphonic acids, -phosphonous acids, -phosphinic acids, esters thereof, halides thereof and mixtures thereof, the catalyst content being 0.01 to 2.0 mol % relative to the total content of components A and B.

Abstract: A polyimide having a high heat-resistance good processability and recurring structural units of the formula (I): ##STR1## wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having at least two carbon atoms, alicyclic radical, monocyclic aromatic radical, fused polycyclic aromatic radical and polycyclic aromatic radical bonded through a direct bond or a bridge member.

Abstract: Tetrapolyimide films derived from 3,3',4,4'-benzophenone tetracarboxylic dianhydride, pyromellitic acid dianhydride, p-phenylene diamine and 4,4'-diaminodiphenyl ether, and their preparation, are described. The tetrapolymer films have low water absorption, low coefficients of thermal and hygroscopic expansion, high modulus and are caustic etachable and can be used in flexible printed circuit and tape automated bonding applications.

Abstract: Fibers may be prepregged with a dope containing polybenzoxazole or polybenzothiazole. The prepreg may be contacted with water or another nonsolvent to coagulate the polymer and form a matrix composite.

Abstract: Azole rings, such as oxazole and thiazole rings, can activate an aromatic ring bonded to a leaving group such as a halogen atom so that the aromatic ring will undergo aromatic nucleophilic substitution. The reaction is useful for making ethers, thioethers and amines containing azole rings. In particular, monomers having azole rings, activated aromatic rings with leaving groups and nucleophilic moieties can react under conditions of aromatic nucleophilic displacement to form non-rigid rob PBZ polymers. The non-rigid rod PBZ polymers can be used to form molecular composites with rigid rod PBZ polymers which molecular composites are not substantially phase separated.

Abstract: A method for preparing high molecular weight polyethermide polymers in a dual solvent system is disclosed. The inventive method provides for polymerizing a diamine monomer and a dianhydride monomer in a solvent system comprised of at least two solvents, a first solvent is selected for its solubility characteristics such that the polyethermide polymer is highly soluble therein and a second solvent is selected for its relatively high boiling point characteristics such that when the second solvent and first solvent are mixed together, the boiling point of the dual solvent system is at least as high as the temperature at which polymerization of said monomers occurs. In one embodiment, a diamine monomer of 4,4'-sulfonyl dianiline (SDAN) is reacted with a dianhydride monomer of bisphenol A dianhydride (BPADA) in the presence of a catalyst and a chain stopper in a dual solvent system comprised of chloroform and ortho-dichlorobenzene. The resulting polyethermide has an intrinsic viscosity exceeding 0.

Abstract: Rigid fluorine-containing compounds, monomers, and polymers based on pentacyclic core systems, such as 12H,14H-5, 7-dioxapentacene with perfluoroalkyl and/or aryl groups in the 12, 14 positions, and 5H,12H-7, 14-dioxapentacene, with perfluoroalkyl and/or aryl groups in the 5,12 positions. These monomers have utility in the preparation of advanced high-performance polymers, particularly polyimides. The rigid pentacyclic core decreases the coefficient of thermal expansion of the polymers, while the fluorinated substituents improve the dielectric constant and water absorption properties. Each monomer unit contains within its pentacyclic core two-O-bridges, and two --CRR.sub.f bridges (where R is aryl, substituted aryl or perfluoroalkyl, and R.sub.f is perfluoroalkyl).

Abstract: Poly(1,2,4-triazoles)(PT) have been prepared by involving the aromatic nucleophilic displacement reaction of di(hydroxyphenyl)-1,2,4-triazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The reactions are carried out in polar aprotic solvents such as sulfolane or diphenylsulfone using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl)-1,2,4-triazole monomers are first synthesized by reacting bis(4-hydroxyphenyl) hydrazide with aniline hydrochloride at 250.degree. C. in the melt and also by reacting 1,3 or 1,4-bis-(4-hydroxyphenyl)phenylenedihydrazide with 2 moles of aniline hydrochloride in the melt. Purification of the di(hydroxyphenyl)-1,2,4-triazole monomers is accomplished by recrystallization.

Abstract: Perfluoroalkylated diaminoesitylene and polymers, preferably polyimides, made therefrom. The necessarily obtainable meta-substitution position of the perfluoroalkyl group with respect to both amino-groups provides an improved diamine and compositions of matter resulting therefrom.

Abstract: Polyimide compositions, films, and electronic devices using polyimides, based on 9-aryl-9(perfluoroalkyl)-xanthene-2,3,6,7-dianhydride and one or more diamines from a selected group, which offers to the polyimides a combination of desirable properties including solubility, pseudo rod-like structure, low linear coefficient of thermal expansion, high glass transition temperature, low dielectric constant, and high modulus.