Abstract: The invention provides aromatic polyamides having an improved resistance to thermo-oxidation. This is achieved by carrying out the polycondensation in the presence of a catalyst system which comprises a mixture of a phosphorus compound and a tin(II) compound or is a compound which contains both elements. The process according to the invention allows aromatic polyamides to be obtained which are resistant to thermo-oxidation (discoloration).

Abstract: Polymers and copolymers having high glass transition temperature and which are soluble in organic solvents are produced from highly hindered biphenols, in particular polyetherketones, polyethersulfones, polyesters and polyetherimides, as well as copolymers based on these polymers may be produced for a variety of applications.

Abstract: Improved imide-containing copolymers comprising, in the aromatic diamine component, p-phenylene diamine and at least one additional aromatic diamine have increased rigidity and useful processability. The copolymers of this invention also may exhibit improved resistance to the detrimental effects of humid environments and retain mechanical properties at elevated temperatures after exposure to humid environments.

Abstract: A method and apparatus are disclosed for conducting a physical process and a chemical reaction by exposing a material containing a volatile substance to microwave radiation where the morphology of said material will change when exposed to such radiation. The power of said radiation is adjusted over time as the morphology of the material changes to maximize the effect of the radiation in order to produce a product in a minimum amount of time that is substantially free of said volatile substance.The method and apparatus can also be used to conduct such a process or reaction with materials that do not contain a volatile material.In one embodiment a method and apparatus are disclosed for manufacturing a polyimide from a precursor in a solvent by exposing the precursor to microwave radiation in a tuneable microwave resonant cavity that is tuned during imidization to achieve critical coupling of the system. Microwave power is controlled to remove the solvent and obtain the desired level of reaction.

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: 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: 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: 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: There are disclosed dibenzofuran amorphous polymer comprising a recurring unit represented by following formula (II) and having a molecular weight giving a reduced viscosity of at least 0.2 dl/g as measured in the form of a 0.5% (W/V) solution in N-methyl-pyrrolidone at 25.degree. C., a process for producing said amorphous polymer, a dibenzofuran copolymer comprising, in addition to a recurring unit represented by following formula (II), at least one type of recurring unit represented by following general formula (III) in a specific proportion and having a molecular weight giving a reduced viscosity of at least 0.2 dl/g as measured in the form of a 0.5% (W/V) solution in concentrated sulfuric acid at 25.degree. C., and a process for producing said copolymer. ##STR1## wherein A is --O--, --CO--, --S--, --SO.sub.2 --, a divalent alkylene group or a single bond and n is a number of 0, 1 or 2.

Abstract: An improved process for the preparation of poly(aryl ether) polymers by reacting, in the absence of dipolar aprotic solvents, an alkali metal double salt of a dihydric phenol with a dihalobenzenoid compound in the presence of a macro bicyclic compound having nitrogen bridgehead atoms linked together by three hydrocarbon bridging chains having in each of the hydrocarbon bridging chains at least one additional hetro atom selected from the group consisting of oxygen, nitrogen and sulfur atoms.The poly(aryl ether) polymer resins produced by the process have a low degree of coloration and excellent mechanical and electrical properties which allow them to be molded into a variety of articles.

Abstract: Molding compounds based on a thermoplastically processible aromatic polyamide. Molding compounds with an improved stability toward thermal oxidation were attained in that the molding compounds in comparison to polyamides contain chemically inert compounds of the formula I ##STR1## The molding compounds according to the invention exhibit an excellent stability toward thermal oxidation.

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: An improved process for the preparation of poly(aryl ether) polymers by reacting, in the absence of dipolar aprotic solvents, an alkali metal double salt of a dihydric phenol with a dihalobenzenoid compound in the presence of an alkoxylated tertiary amine compound having a nitrogen atom linking together three organic chains comprising hydrocarbon groups and in each of the chains at least one oxygen atom.The poly(aryl ether) polymer resins produced by the process have a low degree of coloration and excellent mechanical and electrical properties which allow them to be molded into a variety of articles.

Abstract: An improved process for the preparation of poly(aryl ether) polymers by reacting, in the absence of dipolar aprotic solvents, an alkali metal double salt of a dihydric phenol with a dihalobenzenoid compound in the presence of a macrocyclic polyether compound having one ether ring in which oxygen atoms are separated one from the other by 2 to 3 carbon atoms, the ring having fused thereto from 0 to 4 monocyclic or polycyclic aromatic or saturated hydrocarbon nuclei. The nuclei are attached by vicinal carbon atoms thereof to adjoining ring oxygens in oxygen-carbon-carbon-oxygen arrangement.The poly(aryl ether) polymer resins produced by the process have a low degree of coloration and excellent mechanical and electrical properties which allow them to be molded into a variety of articles.

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 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: 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: 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: A multiply-branched aliphatic-aromatic polyester and a method for producing that polymer. The method comprises condensing a branching reactant represented by the general formula ##STR1## Each j is 1 or 2, each Ar is independently selected from the group consisting of aromatic and heteroaromatic moieties having a total of ring carbons and heteroatoms of from 5 to about 20, each R.sup.1 is a linking group independently selected from alkyl having from 1 to about 6 carbons, fluoroalkyl having from 1 to about 6 carbons, --O--, --S--, --C.tbd.C--, and ##STR2## Z.sup.1 is selected from the group consisting of hydroxyl and --OSi(CH.sub.3).sub.3, and each Z.sup.2 is independently selected from groups having the structural formula ##STR3## wherein each R.sup.2 is independently selected from the group consisting of hydroxy, chloro, bromo, monovalent alkoxide having from 1 to about 6 carbons, and --O--(CH.sub.2).sub.g --OH, wherein g is an integer from 1 to 3, or Z.sup.

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: 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: A multiply-branched aliphatic-aromatic polyester and a method for producing that polymer. The method comprises condensing Z.sup.1 and Z.sup.2 groups of a branching reactant having the general formula Z.sup.1 --Ar--(Z.sup.2)j. In this formula, j is 2 or 3 and Ar is an aryl or heteroaryl group having from 1 to 3, solitary or linked or fused, substituted or unsubstituted, five or six membered rings. One of Z.sup.1 and Z.sup.2 is a group having the ##STR1## general formula in which R.sup.1 is selected from the group consisting of hydroxy, chloro, bromo, monovalent alkoxide having from 1 to about 6 carbons, and --O--(CH.sub.2).sub.d --OH, wherein d is an integer from 1 to 3; and the other is a group having the general formula ##STR2## in which R.sup.2 is a divalent alkyl group having from 1 to about 6 carbon atoms, and g is an integer from 0 to about 100.

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: Polybenzazole polymers may contain perfluorocyclobutane rings to provide a flexible moiety which is stable at high temperatures.

Abstract: The invention describes a film of a thermoplastic, wholly aromatic polyetherketone. The film is amorphous and comprises the polymer PEEKK which is formed of the following repeat unit:--[--Ph--O--Ph--O--Ph--CO--Ph--CO--]--wherein Ph denotes a para-phenylene group.

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: 9,9-Bis(3,5-diphenyl-4-hydroxyphenyl)fluorene a novel compound can be used to produce amorphous poly(arylene ethers) which have high glass transition temperatures and good thermo-oxidative stability and which are soluble in aromatic and chlorinated solvents; the novel fluorene derivative is produced by transalkylation of 9,9-bis(4-hydroxyphenyl)fluorene or 9,9-bis(4-methoxyphenyl)fluorene with 2,6-diphenylphenol.

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: A method for preparing polyimides comprising reacting carbon monoxide, a primary diamine and a reactant selected from the group consisting of bis(o-iodoaromatic ester)s and bis(o-bromoaromatic ester)s, in the presence of solvent and catalyst, said catalyst being a compound of a metal seIected from the group consisting of platinum, palladium and nickel.

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 new polyphosphonates, which are highly branched through polyfunctional phosphorus compounds, are suitable for use as moldings, fibers or films and as flameproofing agents and stabilizers in plastics. The new highly branched polyphosphonates show high resistance to thermal ageing and ensure good processability coupled with high migration resistance at elevated in-use temperatures.

Abstract: A method for preparing poly(imide-amide)s comprising reacting carbon monoxide, an aromatic or heteroaromatic diamine, and an aromatic or heteroaromatic di(trifluoromethane sulfonate), in the presence of solvent and a catalyst One of the aromatic reactants has a nucleus including a phthalimide ring system. The catalyst is a compound of a metal selected from the group consisting of platinum, palladium and nickel.

Abstract: A multiply-branched cycloalkyl polyester and a method for producing that polymer. The method comprises condensing Z.sup.1 and Z.sup.2 groups of a branching reactant having the general formula (Z.sup.1)j-CYCLO-(Z.sup.2)k, in which j is 1 or 2, k is 1 or 2, j+k is 3, 4, or 5. CYCLO is selected from the group consisting of non-aromatic ring systems having from 1 to 8, solitary or fused or linked alkyl or heteroalkyl rings. One of Z.sup.1 and Z.sup.2 is a group having the general formula ##STR1## and the other is --OH, --OSi(CH.sub.3).sub.3, or a group having the general formula ##STR2## R.sup.1 is selected from the group consisting of hydroxy, chloro, bromo, monovalent alkoxide having from 1 to about 6 carbons, and --O-- (CH.sub.2).sub.d --OH, wherein d is an integer from 1 to 3. R.sup.2 is a divalent alkyl group having from 1 to about 6 carbon atoms, and g is an integer from 0 to about 100. If CYCLO is a solitary ring then j+k is 3, 4, or 5. If Z.sup.1 is bonded to a linear aliphatic linking group then Z.sup.

Abstract: A polyamide comprising a recurring unit of the formula (I), ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 is independently a hydrogen atom, a halogen atom, a hydroxyl group, or a group of a carbon skeleton which may contain a hetero atom or a halogen atom, and A.sup.1 is a divalent hydrocarbon group; and a process for the production of a polyamide comprising the recurring unit of the formula (I), which comprises subjecting to a polycondensation reaction a dicarboxylic acid comprising an alicyclic dicarboxylic acid of the formula (a)-1, ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are as defined in the formula (I), and a diamine of the formula (b)-1,H.sub.2 N-A.sup.1 -NH.sub.2 (b)-1wherein A.sup.1 is as defined in the formula (I).

Abstract: The invention relates to polyarylene ethers which contain, based on the total amount of structural elements present in the polyether resin, 5-100 mol % of a recurring structural element of the formula I ##STR1## and 0-95 mol % of a recurring structural element of the formula II ##STR2## in which X and X' independently of one another are --SO--, --SO.sub.2 -- or --CO--, one of the radicals R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is phenyl or phenyl which is substituted by one to three (C.sub.1 -C.sub.4)alkyl groups and the remaining radicals R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently of one another are hydrogen, (C.sub.1 -C.sub.4)alkyl, phenyl or phenyl which is substituted by one to three (C.sub.1 -C.sub.4)alkyl groups, and A is an aromatic radical, at least 25% of the bonds X and/or Y and/or the bridge members contained in A being --SO.sub.2 --.These industrial materials are distinguished by very good mechanical properties and good solubility.

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: Dihydroxydiphenyl bicycloalkanes characterized in that they contain 9 to 13 ring C atoms in the bicycloaliphatic component are disclosed. The disclosed compounds were found to be suitable for the preparation of high molecular weight, thermoplastic polycarbonate resins having favorable properties.

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: A process for preparation of a random copolycarbonate from an ortho-substituted dihydric phenol and a non-ortho-substituted dihydric phenol.

Abstract: The present invention relates to new polyetherimideimides having imideimide group with the following structural formula(I) and inherent viscosity of 0.27.about.0.71 dl/g, which can be made by effecting reaction between an aromatic bis(ether anhydride) and an organic diamine or an aromatic bis(nitro imideimide) and a metal salt of diol.

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: 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: Phosphazene-containing amines having at least one amine or substituted amine moiety reactive with nitrile groups of the phthalonitrile monomers or oligomeric resins are useful curing agents for phthalonitriles. Typically, the phosphazene-containing amines useful as curing agents in the present invention have the formula: ##STR1## wherein each of X.sub.1-6 is a hydrogen, an unsubstituted amine group, or an amine group substituted with C.sub.1 -C.sub.12 alkyl groups or aromatic groups, at least one of X.sub.1-6 includes an amine group, and each of R'.sub.1-6 is an alkyl, aromatic, or alkyl-substituted aromatic moiety, or a linear polymer of the phosphazene-based amine monomer. The curing agents enhance the speed of cure and also add flame retardancy to the cured polymers.

Abstract: The present invention relates to nonlinear optical material comprising nonlinear optical dihydroxy arylhydrazones and to nonlinear optical materials comprising compositions containing at least one divalent moiety of nonlinear optical arylhydrazones. The present invention also relates to polyesters, polyestercarbonates, polycarbonates, polyethers, and poly(hydroxy ether) polymers, incorporating the dihydroxy arylhydrazone as recurring divalent moieties in the backbone of the polymer. The polymeric compositions of the present invention have high glass transition temperatures and exhibit stable nonlinear optical activity at high temperatures over a period of time.

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.