Abstract: A class of soluble polymers having a rigid rod backbone, which when used to cast films, undergo a self-orientation process whereby the polymer backbone becomes more or less aligned parallel to the film surface. This in-plane orientation results in a film that displays negative birefringence. The degree of in-plane orientation and thus, the magnitude of the negative birefringence is controlled by varying the backbone linearity and rigidity of the class of polymers which includes polyesters, polyamides, poly(amide-imides) and poly(ester-imides) through selection of substituents in the polymer backbone chain. By increasing the polymer backbone linearity and rigidity, the degree of in-plane orientation and associated negative birefringence can be increased, and that conversely, by decreasing the polymer backbone linearity and rigidity, the negative birefringence can be decreased.

Abstract: A heat-resistant adhesive film, an adhesion structure obtained using the same, and an adhesion method using the same are disclosed, the film comprising a polyisoimide resin containing at least 40 mol % of an isoimide unit represented by formula (I): ##STR1## wherein R.sub.1 represents a tetravalent aromatic or aliphatic residue; R.sub.2 represents a divalent aromatic or aliphatic residue; and the arrow represents a bond replaceable on isomerization, in the molecule thereof. The isoimide unit of the polyisoimide resin is easily converted to an imide unit on heating, e.g., hot pressing with an adherend, to provide a cover-lay film or a single-sided or double-sided base for printed circuit boards having excellent adhesion, heat resistance, dimensional precision, and workability.

Abstract: A polyimide precursor having a molecular structure obtained by polymerizing (a) 0.97 to 1.03 molar equivalent of a diamine component containing 0.40 molar equivalent or more of aromatic diamine compound represented by the general formula (DA1), and (b) an acid anhydride component containing (1-n.sub.1 /2) molar equivalent of a tetracarboxylic dianhydride and n.sub.1 molar equivalent of at least one selected from the group consisting of maleic anhydride and maleic derivative anhydride, wherein n.sub.1 ranges from 0.02 to 0.40.

Abstract: Controlled molecular weight phenylethynyl terminated imide oligomers (PETIs) have been prepared by the cyclodehydration of precursor phenylethynyl terminated amic acid oligomers. Amino terminated amic acid oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and subsequently endcapped with phenylethynyl phthalic anhydride(s) (PEPA). The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide under nitrogen at room temperature. The amic acid oligomers are subsequently cyclodehydrated either thermally or chemically to the corresponding imide oligomers. Direct preparation of PETIs from the reaction of dianhydride(s) with an excess of diamine(s) and endcapped with phenylethynyl phthalic anhydride(s) has been performed in m-cresol. Phenylethynyl phthalic anhydrides are synthesized by the palladium catalyzed reaction of phenylacetylene with bromo substituted phthalic anhydrides in triethylamine.

Abstract: Polymeric, catalytically active compounds comprising polymer chains to which imidazole groups are linked terminally or laterally are used as catalysts for the dimerization of isocyanates.

Abstract: Novel poly(N-arylenebenzimidazole)s (PNABls) are prepared by the aromatic nucleophilic displacement reaction of novel di(hydroxyphenyl-N-arylene benzimidazole) monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl-N-arylenebenzimidazole) monomers are synthesized by reacting phenyl-4-hydroxybenzoate with bis(2-aminoanilino)arylenes in diphenylsulfone. Moderate molecular weight PNABIs of new chemical structures were prepared that exhibit a favorable combination of physical and mechanical properties. The use of the novel di(hydroxyphenyI-N-arylenebenzimidazole)s permits a more economical and easier way to prepare PNABIs than previous routes.

Abstract: A process is disclosed for making circuit elements by photolithography comprising depositing an antireflective polyimide or polyimide precursor layer on a substrate and heating the substrate at 200.degree. C. to 500.degree. to provide a functional integrated circuit element that includes an antireflective polyimide layer. The antireflective polyimide layer contains a sufficient concentration of at least one chromophore to give rise to an absorbance sufficient to attenuate actinic radiation at 405 or 436 nm. Preferred chromophores include those arising from perylenes, naphthalenes and anthraquinones. The chromophore may reside in a dye which is a component of the polyimide coating mixture or it may reside in a residue which is incorporated into the polyimide itself.

Abstract: A process for preparing polyamideimide resins having high molecular weights as described wherein major problems of prior art processes such as low heat resistance and low melt flowability are improved. Polyamideimide resins having an intrinsic viscosity of 0.4 to 1.50 dl/g as measured on a solution of dimethylacetamide as a solvent at a concentration of 0.5 g/dl at 30.degree. C., are prepared by reacting an aromatic tricarboxylic acid anhydride with an aromatic diamine in N-methyl pyrrolidone solvent in the presence of a first catalyst selected from a group consisting of thionyl chloride, p-toluenesulphonly chloride, sulfuryl chloride, cyanuric chloride and phosphorus trichloride at a temperature of 50.degree. C. to 130.degree. C. over a period of 1 to 5 hours and further reacting the resultant reaction mixture in the presence of a second catalyst which is a compound of the formula (RO).sub.

Abstract: Polyamideimide resins having the formula (I) ##STR1## in which repeating units are bound in a head to tail or head to head manner,R is at least two divalent groups selected from the group consisting of ##STR2## (cis-, trans- conformational mixture) wherein one divalent group is ##STR3## group in a PAI molecule, produced by introducing isophorone diamine into the conventional aromatic polyamideimide resins.

Abstract: This invention concerns positive-working photodefinable polyimide precursors which make use of chemical amplification based on photoacid catalyzed cleavage of acid labile-poly(amic acetal esters).

Abstract: A polyimide comprises structural units represented by the following formula: ##STR1## wherein Ar is a group consisting of 10-90 mole % of a first specific structural sub-unit and 90-10 mole % of a second particular structural sub-unit. A process for the production of the polyimide and a thermosetting resin composition comprising the polyimide and a particular polymaleimide are also disclosed.

Abstract: This invention relates to a novel polyimide or polyimide copolymer having excellent heat resistance and greatly improved processability, and has a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the polyimide or polyimide copolymer and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition.The polyimide comprise a requisite structural unit having one or more recurring structural units of the formula: ##STR1## wherein L is an oxygen atom, carbonyl, isopropylidene or hexafluoroisopropylidene, and X is ##STR2## and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.

Abstract: Thermoplastically processable aromatic polyether amideThermoplastically processable aromatic polyether amide of the formula (I) ##STR1## in which the symbols Ar, Ar', Ar.sub.1, Ar.sub.2, R, R', Y, x, y and z have the following meanings:Ar is a divalent, substituted or unsubstituted, aromatic or heteroaromatic radical or a group--Ar*--Q--Ar*--in whichQ is a bond or an --O--, --C(CH.sub.3).sub.2, --CO--, --S--, --SO-- or --SO.sub.2 -- bridge and Ar* is an aromatic radical. The carbonyl groups of the Ar radical are on non-adjacent ring carbon atoms.A is up to three different radicals.Ar' has the meaning given for Ar or is an Ar--Z--Ar group.In this case, Z is a --C(CH.sub.3).sub.2 -- or --O--Ar*--O--bridge.Y is a --C(CH.sub.3).sub.2 --, --SO.sub.2 --, --S-- or a --C(CF.sub.3).sub.2 --bridge and has up to two different meanings in the same polymer.Ar.sub.1 and Ar.sub.2 are identical or different from one another and are each a substituted or unsubstituted para- or meta-arylene radical.

Abstract: A copolyimide was prepared by reacting 3,4'-oxydianiline (3,4'-ODA) with a dianhydride blend comprising, based on the total amount of the dianhydride blend, about 67 to 80 mole percent of 4,4'-oxydiphthalic anhydride (ODPA) and about 20 to 33 mole percent of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA). The copolyimide may be endcapped with up to about 10 mole percent of a monofunctional aromatic anhydride and has unbalanced stoichiometry such that a molar deficit in the dianhydride blend is compensated with twice the molar amount of the monofunctional aromatic anhydride. The copolyimide was used to prepare composites, films and adhesives. The film and adhesive properties were significantly better than those of LaRC.TM.-IA.

Abstract: Disclosed is a thermally-stable SnO.sub.2 -surfaced polyimide film wherein the electrical conductivity of the SnO.sub.2 surface is within the range of about 3.0.times.10.sup.-3 to about 1.times.10.sup.-2 ohms.sup.-1,. Also disclosed is a method of preparing this film from a solution containing a polyamic acid and SnCl.sub.4 (DMSO).sub.2.

Abstract: Disclosed are bis-meta-benzotrifluoride compounds having the general formula ##STR1## where each A is independently selected from the group consisting of NO.sub.2, NH.sub.2, and NH.sub.3.sup.+ Z.sup.-, Z.sup.- is an anion and B is selected from the group consisting of O, CO, S, SO, and SO.sub.2. The diamine compounds are useful as monomers in making polyimides, polyamide-imides, and polyamides.

Abstract: Alcohol-soluble aromatic heterocyclic copolymers having repeating units of the formula: ##STR1## wherein x has a value of 0.05 to 0.50 and y has a value of 1.0-x. These copolymers are useful in the preparation of organic/inorganic hybrid materials having transparency which comprise the sol-gel derived, hydrolytically condensed reaction product of a metal alkoxide of the formula M(OR).sub.w wherein R is a lower alkyl group, M is Si, Ti, Al or a mixture thereof, and w is the valence value of M, and the above copolymer.

Abstract: Polyimides are obtainable by reacting a dianhydride component with a diamine component, at least one diamine containing cycloaliphatic units, with the proviso that the dianhydride component is a mixture of different dianhydrides if the diamine component consists only of one diamine containing cycloaliphatic units and the diamine component is a mixture of different diamines if the dianhydride component consists of only one dianhydride.

Abstract: Polyimides comprising recurring units of the following general formula (1) ##STR1## wherein Ar.sub.1 represents a tetravalent aromatic group and each Ar.sub.2 represents a divalent aromatic group. Polyimide copolymers and preparations of the polyimides and the polyimide copolymers are also described.

Abstract: Alcohol-soluble aromatic heterocyclic polymers having repeating units of the formula: ##STR1## wherein X is --O-- or --S--, and R is selected from the group consisting of: ##STR2## and R' is selected from the group consisting of alkyl having 1 to 5 carbon atoms, alkaryl having 7 to 12 carbon atoms, aralkyl having 7 to 12 carbon atoms and substituted aromatic having 1 to 3 substituent groups.The alcohol-soluble polymers may be used for fabricating organic/inorganic hybrid composites with metal alkoxides M(OQ).sub.v, wherein M is Si, Ti, Al or the like and Q is a lower alkyl group. These polymers can also be used to coat materials or substrates which are susceptible to attack by highly corrosive acids. On drying, the ionic bond between the trialkylamine and the sulfo group is broken and the polymer reverts to the parent structure, thereby leaving a polymer coating. Yet further, the original amine can be exchanged with a less volatile amine or an amine having a desired functionality.

Abstract: Solutions of polyimide-forming substances containA) polyamines andB) amides and/or esters of tetracarboxylic acids, the amido or ester groups carrying substituents selected from the group consisting of carboxyl, sulfo and silicon-containing groups,and are used as polyimide coatings.

Abstract: Solutions of polyimide-forming substances containA) aromatic or partly aromatic diamines andB) tetraesters of imide-forming aromatic or partly aromatic tetracarboxylic acids or mixtures of these tetraesters with the corresponding tri-, di- and/or monoesters.These solutions are suitable for the production of coatings.

Abstract: The present invention relates to an amorphous polyimide or a polyimide copolymer having a requisite structural unit consisting of one or more recurring structural units represented by the formula (1): ##STR1## wherein X is a direct bond, oxygen atom or sulfur atom, and R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are individually a hydrogen atom or methyl, and Ar is a tetravalent radical having 6 to 27 carbon atoms and being selected from the group consisting of a monoaromatic radical, condensed polyaromatic radical and noncondensed polyaromatic radical having aromatic radicals connected to each other with a direct bond or a bridge member.Polyimide and the polyimide copolymer of the invention has excellent heat resistance, is outstanding in melt-flow stability, has greatly improved processability, and can be applied to structural materials, and electric- electronic appliances.

Abstract: Polyimide polymers of the following recurring structure and the corresponding polyamic acids are disclosed: ##STR1## wherein AR.sub.1 is ##STR2## where X is O, S, SO, SO.sub.2, CO, C(CF.sub.3).sub.2, C(CH.sub.3).sub.2, Si(CH.sub.3).sub.2, or a single bond, wherein AR.sub.2 may be pyromellitic dianhydride, a substituted pyromellitic dianhydride, naphthanoic dianhydride, or ##STR3## where Y is O, S, SO, SO.sub.2, CO, C(CF.sub.3).sub.2, C(CH.sub.3).sub.2, Si(CH.sub.3).sub.2 --O--AR--O--, or a single bond, where AR is an aromatic nucleus.

Abstract: A negative birefringent film, useful in liquid crystal displays, and a method for controlling the negative birefringence of a polyimide film is disclosed which allows the matching of an application to a targeted amount of birefringence by controlling the degree of in-plane orientation of the polyimide by the selection of functional groups within both the diamine and dianhydride segments of the polyimide which affect the polyimide backbone chain rigidity, linearity, and symmetry. The higher the rigidity, linearity and symmetry of the polyimide backbone, the larger the value of the negative birefringence of the polyimide film.

Abstract: This invention relates to a novel thermoplastic and amorphous polyimide which is readily soluble in organic solvent, a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the thermoplastic polyimide and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition, a polyimide-based composite obtained by molding the above soluble and thermoplastic polyimide in combination with a fibrous reinforcement, and a fibrous reinforcement having a surface modified with the above polyimide.

Abstract: A solvent resistant copolyimide was prepared by reacting 4,4'-oxydiphthalic anhydride with a diaimine blend comprising, based on the total amount of the diamine blend, about 75 to 90 mole percent of 3,4'-oxydianiline and about 10 to 25 mole percent p-phenylene diamine. The solvent resistant copolyimide had a higher glass transition temperature when cured at 350.degree. , 371.degree. and 400.degree. C. than LaRC.TM.-IA. The composite prepared from the copolyimide had similar mechanical properties to LaRC.TM.-IA. Films prepared from the copolyimide were resistant to immediate breakage when exposed to solvents such as dimethylacetamide and chloroform. The adhesive properties of the copolyimide were maintained even after testing at 23.degree., 150.degree., 177.degree. and 204.degree. C.

Abstract: Polyimides comprising recurring units of the following general formula (1) ##STR1## wherein R.sub.1 represents a tetravalent aromatic group. Polyimide copolymers and preparations of the polyimides and the polyimide copolymers are also described.

Abstract: A polyimide precursor composition solution includes a tetracarboxylic acid component containing not less than 70 mol % of at least one selected from the group consisting of benzenetetracarboxylic acid and its reactive derivatives; a maleimide compound; and a diamine component containing not less than 70 mol % of 2,2'-substituted-4,4'-benzidine represented by the general formula (I) and siloxydiamine amounting to from 1 to 10 mol %. The tetracarboxylic acid component, the maleimide compound and the diamine component are dissolved in a solvent which is consisting essentially of .gamma.-butyrolactone. The amount of the tetracarboxylic acid component is substantially equivalent to that of the diamine component. The amount of the maleimide compound is from 5 to 30 wt % of the total weight of the tetracarboxylic acid and the diamine component.

Abstract: Copolyimides from 1,4-bis(4-aminophenoxy)-2-phenylbenzene and m- or p-phenylene diamine with biphenyl dianhydride exhibit a high Tg and reduced melt viscosity.

Abstract: Polyimide oligomers are described which comprise the condensation product of: at least one phenylindane diamine and at least one aromatic bis(ether anhydride). The polyimide oligomers of the invention are readily processed to form solution prepregable polyimide composites having high glass transition temperatures and high temperature and oxidative stability. More particularly, the present invention provides for crosslinkable polyimide oligomers prepared by reacting, in a suitable solvent under an inert atmosphere, a mixture of monomers comprising: (A) an aromatic diamine component comprising from about 25 to 100 mole % of at least one phenylindane diamine; (B) a dianhydride component comprising from about 25 to 100 mole % of at least one aromatic his(ether anhydride); and (C) at least one end-cap monomer selected from the group consisting of monoanhydrides, acyl halides and aromatic amines, wherein each end-cap monomer contains at least one crosslinkable functional group in the molecule.

Abstract: Solutions of polyimide-forming substances containA) aromatic or partly aromatic polyamines andB) amides or a mixture of esters and amides of tetracarboxylic acids.Solutions are useful as coating compositions.

Abstract: A photosensitive resin composition comprising, as its main ingredient, a poly(amic acid) resin constituted of a diamino compound represented by formula: ##STR1## and optionally used other diamino compound and a tetracarboxylic acid dianhydride as its constituent monomers and/or a poly(amic acid) ester resin obtained by esterifying said poly(amic acid) resin and/or a polyimide resin obtained by a dehydrating or alcohol-eliminating ring-closure reaction of said poly(amic acid) resin or poly(amic acid) ester resin has an excellent developability and a high film strength and can form a relief patter of low thermal expansion.

Abstract: The present invention relates to a polyimide based resin composition comprises 1 to 50 parts by weight of polyetherimide for 100 parts by weight a resin composition comprising 50 to 99 parts by weight of polyarylether ketone and 50 to 1 parts by weight of polyimide having specific structural units.The polyimide based resin compositions have excellent fatigue characteristics and creep resistance and are expected widely to apply in field of machine and automobile parts which is required permanence for mechanical strength.

Abstract: This invention relates to a novel fluorine-containing polyimide or polyimide copolymer being colorless and having transparency and very low dielectric characteristics, and has a novel aromatic diamino compound used for the polyimide, a preparation process thereof, a polyimide-based resin composition comprising the polyimide or polyimide copolymer and a fibrous reinforcement, a process for preparing the resin composition, an injection molded article of the resin composition.

Abstract: The present invention is an oligomer represented by the formula: ##STR1## wherein X is a moiety selected from the group consisting of: ##STR2## where each Y is independently S, O, CH.sub.2, C.dbd.O, CH.sub.3 --C--CH.sub.3, O.dbd.S.dbd.O, or CF.sub.3 --C--CF.sub.3.In another aspect, the present invention is a polymer of the above-described oligomer.

Abstract: The present invention provides novel substituted biphenyl pyrazines or pyrazine derivatives ("BPD") which are functional and have useful application as a monomer for a variety of high performance polymers such as polyester, polyarylate, polycarbonate, polyetherketones, epoxides, polyimides, polyamides, and polyamides-imides; and as pigments for coating compositions such as paints. These BPD have the general formula: ##STR1## wherein R.sub.1 -R.sub.8 and n are defined herein.

Abstract: Copolyamic acid is obtained from tetracarboxylic acid dianhydride, diamine and a fluorinated diamine and/or fluorinated tetracarboxylic acid dianhydride; and optionally ester or amine salt derivative thereof to obtain radiation sensitive polymer; and low optical high thermally stable polyimide from curing the above polyamic acid and/or derivative thereof.

Abstract: The invention is a direct process for preparing semi-crystalline polyimides. This process comprises the steps of: providing a polar aprotic solvent, adding a dianhydride and a diamine to the solvent to form a mixture, stirring the mixture at ambient temperature, and adding glacial acetic acid to the mixture to provide a ratio of polar aprotic solvent to glacial acetic acid which ranges from about 90 to 10 to about 75 to 25 by volume to form a solution. The solution was heated to a range from about 110.degree. C. to about 140.degree. C. to form a polyimide precipitate. The polyimide precipitate was recovered as a semi-crystalline polyimide powder.

Abstract: This invention provides (1) a granular material of a polyimide precursor, which has excellent solubility in solvents and excellent moldability and from which a polyimide molding having excellent mechanical properties can be produced, (2) a mixture of a granular material of a polyimide precursor with a solvent, in which the polyimide precursor shows excellent storage stability and (3) a process for the production of a granular material of a polyimide precursor, in which a solvent can be easily removed. Particularly provided are a polyimide precursor granular material having an intrinsic viscosity of 0.7 or higher and a polyimide precursor mixture which consists of a polyimide precursor granular polyimide having an intrinsic viscosity of 0.7 or higher and a solvent that does not exhibit a strong-mutual interaction with the polyimide precursor, as well as a process for the production of the polyimide precursor granular material.

Abstract: In one aspect, the present invention relates to polyimides having excellent thermal resistance and process for preparing the same comprising carrying out condensation of 4,4'-bis(3-aminophenoxy)biphenyl with pyromellitic dianhydride in the presence of a different diamine compound and optionally with a different tetracarboxylic acid dianhydride.In a second aspect, the present invention relates to a heat resistant resin composition consisting essentially of an aromatic polyetherimide and a defined polyimide.In a third aspect, the present invention relates to a polyimide resin composition comprised on a defined polyimide and a separate high-temperature engineering polymer.In a fourth aspect, the present invention relates to a resin composition comprised of a defined polyimide and an aromatic polyamideimide.

Abstract: A nonlinear optical material composed of a polyimide obtained from a diamine and/or a diacid anhydride or dithioacid anhydride substituted by a portion having a nonlinear optical effect or of molecules having a benzocyclobutene structure substituted at the portions having an nonlinear linear optical effect.

Abstract: A moldable polyimide resin composition which has melt-flowability and excellent processability in addition to essential heat-resistant of polyimide and comprises an aromatic bisimide compound and polyimide resin. A further aspect relates to a carbon fiber reinforced polyimide resin composition which has excellent mechanical strengths and comprises a carbon fiber coated with aromatic bisimide compound on the surface and the polyimide resin. A still further aspect relates to a novel bisimide compound which is very useful as the aromatic bisimide compound in the composition.

Abstract: Two monomers containing meta-biphenylenedioxy moieties were prepared. One monomer, a diamine, is used to prepare polyimide, polyamide, and epoxy polymers. The other monomer, a dianhydride, was used to prepare polyimide polymers. These polymers are used to make films, coatings, and selective membranes.

Abstract: The present invention relates to a polymeric film in-line coated with polyamido-polyethyleneimine to render the film receptive to direct extrusion coating with other polymers or to ink adhesion and to a method of making the same. Additionally, the present invention relates to an oriented polymeric film which has been in-line coated with polyamido-polyethyleneimine so that it has anti-static properties for other packaging applications.

Abstract: Benzophenone iminodiimides of the formula I ##STR1## which Y denotes hydroxyl or carboxyl, R.sub.1 denotes the optionally substituted radicals alkylene, phenylene or benzylidene, R.sub.2 denotes the radicals OH, substituted or unsubstituted alkyl or NH--CO--NHR.sub.3 and R.sub.3 denotes the radicals H, alkyl, phenyl or benzyl, processes for their preparation and polymers prepared therefrom.

Abstract: Provided is a new process useful for preparing arylsulfonyl halides, which comprises the addition or drowning of halosulfonation reaction products, produced by the reaction of aromatic compounds (arenes), with excess halosulfonic acid, into C.sub.3 -C.sub.6 aliphatic ketones, preferably acetone, isopropyl alcohol, or mixtures thereof, instead of drowning into water as is known in the art of aromatic sulfonyl chloride preparation. Less heat of reaction is observed, thus making the drowning of the halosulfonation reaction mixture safer and more controllable. Further, less hydrogen chloride gas is evolved from the drowning mixture and generally more highly pure arylsulfonyl chlorides are produced.

Abstract: A diamine compound of the general formula ##STR1## wherein the arrows denote isomerism, R.sub.1 is a divalent aromatic group selected from the group consisting of ##STR2## R.sub.2 is a tetravalent aromatic group selected from the group consisting of ##STR3## and R.sub.4 is a monovalent aliphatic group selected from the group consisting of ethyl and isopropyl; and, a process for preparing same.

Abstract: Polyimide optical waveguide structures comprising a core within a cladding wherein at least one of the core and the cladding is a polyimide containing 6FDA, BTDA, an aromatic diamine having bulky methyl groups ortho to the amine, and a co-diamine wherein the polyimides have the properties of low optical loss, low optical absorbance, controllable refractive index, and high thermal stability, and wherein the polyimides are photosensitive and solvent resistant.

Abstract: A polyimide optical material, composed of a perfluorinated polyimide having a perfluorinated repeating unit represented by general formula (1) ##STR1## wherein R.sub.1 is a tetravalent perfluorinated organic group; and R.sub.2 is a divalent perfluorinated organic group.