Abstract: This invention relates to polyimides having improved thermal-oxidative stability, to the process of preparing said polyimides, and the use of polyimide prepolymers in the preparation of prepregs and composites. The polyimides are particularly useful in the preparation of fiber-reinforced, high-temperature composites for use in various engine parts including inlets, fan ducts, exit flaps and other parts of high speed aircraft.

Abstract: A polyimide resin having phenolic hydroxyl radicals in its skeleton is prepared using a diamine bearing an aromatic ring having an amino radical attached thereto and another aromatic ring having a phenolic hydroxyl radical. The polyimide resin and a composition comprising the polyimide resin, an epoxy resin and a curing agent are suited for use as varnish, adhesive and adhesive film for which adhesion and heat resistance are required.

Abstract: Provided are polyimide and a thin film thereof which have a three-dimensional structure and therefore are excellent in a mechanical strength and a heat resistance as compared with those of conventional linear polyimide. The polyimide is obtained from a salt of multifunctional amine represented by Formula (1): (wherein A represents a tetravalent organic group, and n represents an integer of 0 to 3) and tetracarboxylic diester represented by Formula (2): (wherein B represents a tetravalent organic group having 1 to 20 carbon atoms, and R1 and R2 each represent independently an alkyl group having 1 to 5 carbon atoms).

Abstract: Polyimide precursors contained in resin compositions of the present invention have a polymer structure unit represented by formula (1) below: wherein chemical structure A2 includes an alicyclic compound but not an aromatic compound such as a benzene ring so that they provide excellent light transmission over a wide wavelength range. The polyimide precursors are imidized at 7.5% or more and 36% or less so that they are less soluble in developing solutions and therefore are not dissolved in the developing solutions at unexposed parts. Thus, the resin compositions of the present invention can be used to form a resin film having a precise pattern by exposure and development.

Abstract: A polyimide excelling in heat resistance, chemical resistance, water repellency, dielectric characteristics, electrical characteristics, and optical characteristics and a polyamide acid useful as the raw material therefor are provided. Specifically, a polyamide acid containing a chlorine atom and a fluorine atom and comprising a repeating unit represented by the following formula (1): (wherein X and X? independently denote a divalent organic group; Y and Y? independently denote a chlorine, bromine, or iodine atom; p and p? denote independently denote the number of fluorine atom {F in the formula (1)} bonded to the relevant benzene ring, representing an integer of 0-3; q and q? independently denote an integer of 0-3; and p+q total 3, and p?+q? total 3).

Abstract: Methods of reducing the amount of undesirable cyclic oligomer by-products in the production of polyetherimides are disclosed. The resulting polyetherimides have enhanced thermomechanical properties.

Abstract: A polyimide composition and a process to prepare polyimide resins with reduced plate out and mold deposits is described. During resin molding operations the low plate out resins show a longer period of operation between cleaning of equipment leading to more efficient operation.

Abstract: A process of preparing a polyimide of the present invention comprises effecting an imidization reaction of a diamine and a tetracarboxylic dianhydride in a solvent containing 50 to 100% by weight of an equimolar composition of a nitrogen-containing cyclic compound indicated by chemical formula (1) below and a phenol indicated by chemical formula (2) below: in formula (1), X represents —CH2— or —N(CH3)—, and in formula (2), R1 and R2 may be the same as, or different from, each other and represent each any one of —H, —OH, —CH3, —C2H5, —C3H7, —C4H9, —C5H11, —C6H13, —C7H15, —C8H17, —C9H19, —C10H21, —OCH3, —O(C6H5), —NO2, —Cl, —Br and —F.

Abstract: A series of low melting and low viscosity phenylethynyl end-capped polyimides (PETIs) possessed of long term thermal and mechanical stability useful as films, melt coatings, adhesives, matrix and RTM resins and particular as coatings for optical fibers and phenylethynyl end-capped bismides blended with PETIs are disclosed. Processes for their production including: 1) modification of PETI-5 oligomer by molecular weight adjustments by blending with reactive low melting phenylethynyl end-capped imide monomers, 2) modification of the PETI-5 backbone structure with other diamine components, and 3) modification of the PETI-5 backbone with bulky fluorinated groups are also disclosed.

Abstract: The invention provides a polyimide film manufactured from a polyamic acid prepared from pyromellitic dianhydride in combination with 10 to 60 mol % of phenylenediamine and 40 to 90 mol % of 3,4?-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.

Abstract: A polyimide-based polycondensate which may be used as an insulation film by coating a copper foil with the polycondensate and by heating the coated copper foil, which insulation film does not warp the foil, as well as a production process thereof, is disclosed. The polycondensate according to the invention is a solvent-soluble polycondensate containing a benzoxazole component having a carboxylic group and an imide component having a phenolic hydroxyl group, which is obtained by dehydration-condensing one or more tetracarboxylic dianhydrides with one or more aromatic diamines having an amino group and a phenolic hydroxyl group, the amino group and the phenolic hydroxyl group being located at ortho positions with respect to each other, by heating the one or more tetracarboxylic dianhydrides and the one or more aromatic diamines at 150° C. to 220° C. in the presence of an acid catalyst.

Abstract: The present invention provides an optical polyimide precursor for use in making a polyimide. The precursor is defined by the following formula: wherein X is Cl, Br, oxo-halide, or fully halogenated alkyl, and A is a divalent aromatic or halogenated aromatic moiety. The present invention provides a method of preparing a diamine compound for use as an optical polyimide precursor. The method includes the steps of dissolving 2-chloro-5-nitrobenzotrifluoride and a diol in N,N-dimethylacetamide to form a solution, adding potassium carbonate, tert-butylammonium chloride and copper powder to said solution and heating the resulting mixture, removing the copper, precipitating and recrystallizing a dinitro-compound resulting from heating the mixture, and dissolving the dinitro-compound and reducing the dinitro-compound to yield a diamine compound.

Abstract: A thermosetting polyimide resin composition is provided which comprises a polyimide resin and an epoxy resin, which has excellent heat resistance, low dielectric constant and low dielectric loss tangent and also yields a cured article having good mechanical properties such as tensile strength and tensile elongation. Also, a process for producing a polyimide resin used in the polyimide resin composition is provided. The thermosetting polyimide resin composition comprises a polyimide resin (X), which has a carboxyl group and a linear hydrocarbon structure having a number-average molecular weight of 300 to 6,000, and an epoxy resin (Y).

Abstract: A method for the synthesis of poly(etherimide)s comprises the reaction of 4-halotetrahydrophthalic anhydride with an activating primary amine to yield an activated 4-halotetrahydrophthalimide. Activated 4-halotetrahydrophthalimide may then be aromatized and treated with the disodium salt of a bis(phenol) to yield an activated bisimide. The activated bisimide may then be directly treated with a diamine to yield poly(etherimide)s.

Abstract: A polyimide is disclosed of the formula: CG1 and CG2 are independently electron-accepting and/or electron-donating groups; x is an integer from about 3 to about 3000; ODAH is any of a number of known dianhydride residues; ODAM is any of a number of known diamine residues; and m, n, o, and p cumulatively add to 1.0, with the sum of m and n ranging from about 0.05 to about 1.0, the sum of o and p ranging from about 0 to about 0.95, the sum of m and o being about 0.5 and the sum of n and p being about 0.5. In addition, a film structure comprising the polyimide and devices utilizing the film structure are disclosed.

Abstract: In a step of polymerizing polyamic acid by mixing tetracarboxylic acid dianhydride and diamine and polycondensating the tetracarboxylic acid dianhydride and diamine under the presence of a polymerization-use solvent, a tetracarboxylic acid dianhydride slurry in which a tetracarboxylic acid dianhydride is dispersed in a dispersion medium is used. According to this, it is possible to directly manufacture a polyamic acid solution having a high concentration of polyamic acid more than or equal to 10% by weight. Especially, even if a tetracarboxylic acid dianhydride having low solubility in the polymerization-use solvent, it is possible to effectively manufacture a polyamic acid solution having high solids content, by a simple process and in a short time.

Abstract: Copolyetherimides comprise phthalimide structural units comprising both 3- and 4-linkages, wherein the designations 3-linkage and 4-linkage refer to the isomeric positions on the phthalimide ring in the totality of phthalimide-comprising structural units in the copolymer. The products have excellent properties, including high glass transition and heat distortion temperatures, high ductility and good melt flow properties, and low polydispersity.

Abstract: The following invention relates to phenyl-linked polybenzoxazoles having terminal, aryl- or heteroaryl-attached cyanate groups which can be used for adhesive bonding and as dielectrics, especially for electronic components, and to a process for preparing them.

Abstract: Polymers are prepared from A) 60 to 95 percent by weight of a mixture including A1) 20 to 70 percent by weight of hydroxyalkyl amino triazines and A2) 30 to 80 percent by weight of bis(hydroxyalkyl) amino triazines B) 5 to 40 percent by weight of polyfunctional compounds selected from one or more of B1) polyisocyanates and/or oligomeric polyesters or polyethers with isocyanate end groups, B2) aliphatic dicarboxylic acids, esters, chlorides or anhydrides, or aromatic polybasic acids, esters, chlorides or anhydrides, B3) aliphatic or aromatic diglycidal compounds or triglycidyl compounds, and, optionally, C) 1 to 20 percent by weight of aliphatic, cycloaliphatic or aromatic dihydroxy compounds, polyalkylene glycols and aliphatic aldehydes.

Abstract: The present invention provides a method for easily producing a high-molecular weight polyimide resin at high yield by drying and heating a mixture mixed by material monomers of polyimide.

Abstract: This invention is a highly concentrated stable solution of polyimide precursors (monomers) having a solids content ranging from about 80 to 98 percent by weight in lower aliphatic alcohols i.e. methyl and/or ethyl alcohol. The concentrated polyimide precursor solution comprises effective amounts of at least one aromatic diamine, at least one aromatic dianhydride or a lower molecular weight alkyl ester of said dianhydride, and a monofunctional endcap including monoamines, monoanhydrides and the lower alkyl esters of said monoanhydrides. These concentrated polyimide precursor solutions are particularly useful for the preparation of fibrous prepregs and composites for use in structural materials for military and civil applications.

Abstract: The present invention is directed to a process for electrostatically spinning fibers of polyamic acid and the fibers thus produced as well as the nonwoven webs that may be formed from the fibers. According to the processes of the present invention, polyamic acid solutions may be electrostatically spun to form fibers of very small diameter, such as, for instance, less than about 5 &mgr;m in average diameter. The fibers may be formed into a nonwoven web having very high specific surface area and large porosity. The polyamic acid may be converted to polyimide to form a polyimide nonwoven web. The polyimide nonwoven web may then be activated through a carbonization process to enhance the electrochemical properties of the web. The nonwoven webs of the invention may be utilized in a variety of electrochemical applications including, for example, electrical double layer capacitors.

Abstract: A method of making a solution of a polyimide from a diamine monomer and a dianhydride monomer is disclosed. A solution or slurry of one of the monomers in a solvent that boils at a temperature between about 80° C. and about 160° C. is prepared. The solution or slurry is heated to a temperature between about 80° C. and about 160° C. and the other monomer is slowly added to the solution or slurry. Polyamic acid that is formed quickly imidizes to form the polyimide.

Abstract: Polyimides having a desired combination of high thermo-oxidative stability, low moisture absorption and excellent chemical and corrosion resistance are prepared by reacting a mixture of compounds including (a) 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), (b) 3,4′-oxydianiline (3,4′-ODA), and (c) 5-norbornene-2,3-dicarboxylic anhydride (NA) in a high boiling, aprotic solvent to give 5 to 35% by weight of polyamic acid solution. The ratio of (a), (b), and (c) is selected to afford a family of polyimides having different molecular weights and properties. The mixture first forms a polyamic acid precursor. Upon heating at or above 300° C., the polyamic acids form polyimides, which are particularly suitable for use as a high temperature coating, adhesive, thin film, or composite matrix resin.

Abstract: The present invention relates to methods for the preparation of polyesters, poly(ester amide)s and poly(ester imide)s. The materials obtained by the methods of present invention are useful as fluid separation membranes and as high performance materials.

Abstract: A film-formable polyimide copolymer, which comprises two kinds of tetracarboxylic acid dianhydride consisting of (A) pyromellitic acid dianhydride and (B) 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride, and (C) 6-amino-2-(p-aminophenyl)benzimidazole has a heat-resistant dimensional stability without any deterioration of mechanical properties inherent in the polyimide resin when used as a film.

Abstract: Polyhydroxyamides are polymerized to form highly-crosslinked, temperature-stable polymers. The polyhydroxyamides include as their central, parent structure a benzenetricarboxylic acid to which side chains containing a terminal reactive group are attached by an amide bond. By way of this reactive group, highly crosslinked polymers can be formed. In addition, the polyhydroxyamide can be added as an additive to polymers in order to bring about three-dimensional crosslinking.

Abstract: An alkyldiamine having excellent polymerization reactivity, a polyimide comprising it as a constituting element, and a liquid crystal alignment film excellent in uniformity of liquid crystal alignment, are presented. Namely, the present invention relates to a diaminobenzene derivative represented by the following general formula (1) and to a polyimide obtained by reacting a diamine containing at least 1 mol % of the diaminobenzene derivative represented by the general formula (1), with at least one compound selected from a tetracarboxylic. dianhydride and its derivatives, to obtain a polyimide. precursor having a reduced viscosity of from 0.05 to 5.0 dl/g (in N-methylpyrrolidone at a temperature of 30° C., concentration: 0.5 g/dl) and ring-closing it, and having a repeating unit represented by the general formula (2). Further, the present invention relates to a liquid crystal alignment film containing at least 1 mol % of the above repeating unit.

Abstract: The aromatic diamine compound of the present invention is represented by the following formula (1), and from the aromatic diamine compound a polyimide having a repeating unit represented by the following formula (4), which has low-temperature adherability, can be obtained. In the formulas (1) and (4), n is an integer of 3 to 7, each R is independently an atom or a group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group, the same or different two hetero atoms selected from nitrogen atoms and oxygen atoms bonded to each benzene ring are at the ortho- or meta-positions to each other on at least one benzene ring, and when n is 3, the hetero atoms are at the ortho- or meta-positions to each other on all the benzene rings. In the formula (4), Y is a tetravalent organic group.

Abstract: A solvent-free, catalyst-free and contamination-free method of synthesis of polyimides is disclosed. The method includes polymerizing a diamine with 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) at a pressure of 0.1-760 mm Hg, preferably a reduced pressure at about 36 mm Hg, and a temperature of 90-400° C., preferably 10-240° C.

Abstract: The invention is a polyimide, random copolymer having repeating units of the formula (1): wherein R1 and R2 each represent a divalent group selected from and R1 and R2 may be the same or different; and x=0.60 to 0.80, y+z=0.40 to 0.20, and x+y+z=1.00, and a linear expansion coefficient at 100 to 200° C. is in the range of from 10 to 20 ppm/K. This is a useful polyimide that can be a polyimide circuit substrate material capable of keeping flat, neither shrinking nor expanding in its laminate.

Abstract: A process for the preparation of a reactive friable polyimide powder comprises dissolving an aromatic dianhydride and an organic diamine in a high-boiling, aprotic organic solvent to form a reaction solution; heating the reaction solution under imidization conditions to form an insoluble reactive polyimide and to effect substantially complete distillation of the water of reaction out of the reaction solution; and separating the insoluble reactive polyimide from the reaction solution to form a reactive friable polyimide powder.

Abstract: Disclosed are a polyamic acid having repeating units represented by the formula (1): wherein the norbornane skeleton of comprises four components of and their contents satisfy the following: 1%≦2,5-[diexo]≦90%, 1%≦2,5-[exo,endo]≦90%, 1%≦2,6-[diexo]≦90%, 1% ≦2,6-[exo,endo]≦90%, provided that (2,5-[diexo])+(2,5-[exo,endo])+(2,6-[diexo])+(2,6-[exo,endo])=100%, R represents from 4 to 27 carbon atoms, and represents a tetravalent group selected from the group consisting of an aliphatic group, a monocyclic aliphatic group, a condensed polycyclic aliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed polycyclic aliphatic or aromatic group which is composed of cycloaliphatic or aromatic groups mutually bonded to each other either directly or via a crosslinking member; and a polyimide

Abstract: The present invention provides a polyimide resin, a resin composition, an adhesive solution, a film-state joining component, and an adhesive laminate film soluble in a solvent having excellent heat resistance and adhesion, capable of bonding and curing at relatively low temperatures.

Abstract: An acid dianhydride, together with a diamine, is heated in an organic polar solvent in the presence of &ggr;-caprolactone or &bgr;-butyrolactone as an acid catalyst to prepare a polyimide having an average molecular weight of 10,000 to 300,000. This production process can realize the production of a polyimide which is soluble in a solvent and has high processability and stability.

Abstract: The invention provides a polyimide film manufactured from a polyamic acid prepared from pyromellitic dianhydride in combination with 10 to 60 mol % of phenylenediamine and 40 to 90 mol % of 3,4′-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.

Abstract: A polyimide film that exhibits improved peel strength when clad with a metal layer is prepared by reacting a polyamic acid polymer and an esterified polyamic acid oligomer. The esterified oligomer has from two to twenty repeating units and at least two crosslinkable groups selected from the group consisting of carbonyl, cyano, hydroxy, alkyne, maleimide, norbornene and sulfonyl groups. The polyamic acid is dissolved in a solvent to form a polyamic acid solution, which has a minimum gel-film forming temperature, or a minimum green film forming temperature, associated therewith. The esterified polyamic acid oligomer has an imidization temperature, which is higher than the minimum gel-film forming temperature, or the minimum green film forming temperature, of the polyamic acid solution.

Abstract: The present invention provides PMR-type polyimides that exhibit lower melt viscosities than PMR-type polyimides of the prior art. These PMR-type polyimides are created by incorporating flexible linkages, such as kinked structures and twisted or non-coplanar moietes into the backbone structure of the PMR. Specifically, the present invention provides for the production of PMR-type polyimides having 2,2′-disubstituted biaryls in the polymer backbone.

Abstract: Disclosed is a polyamide ester which comprises a plurality of specific amide ester recurring units including, in a specific ratio, recurring units containing a tetravalent benzene group and recurring units containing a tetravalent diphenyl ether group, and which is adapted to be converted to a polyimide in a coating form by heat-curing, wherein the polyimide coating exhibits a residual stress of 33 MPa or less as measured with respect to a 10 &mgr;m-thick polyimide coating formed on a silicon substrate. Also disclosed is a polyamide ester composition comprising a plurality of different polyamide esters, wherein the plurality of different polyamide esters collectively contain, in a specific ratio, the recurring units containing a tetravalent benzene group and the recurring units containing a tetravalent diphenyl ether group.

Abstract: The invention relates to a semi-permeable membrane separation process and device in which the said membranes comprise sulphonated polyimides. The present invention also relates to the use of sulphonated polyimide membranes in separation processes and devices using semi-permeable membranes.

Abstract: The invention is directed to method for making a polyimide by converting the dianhydride to the ester acid and reacting the ester acid with a diamine. The invention allows for the controlled addition of aliphatic diamines resulting in control of the polyimide properties such as the glass transition temperature, solubility, and melt processability.

Abstract: A polyimide film is manufactured from a random copolymeric, block copolymeric or interpenetrating polymer network-type polyamic acid prepared from pyromellitic dianhydride in combination with 22 to 78 mol % of 4,4′-oxydianiline and 22 to 78 mol % of 3,4′-oxydianiline, based on the overall diamine. The polyimide film, when used as a metal interconnect board substrate in flexible circuits, chip scale packages (CSP), ball grid arrays (BGA) or tape-automated bonding (TAB) tape by providing metal interconnects on the surface thereof, achieves a good balance between a high elastic modulus, a low thermal expansion coefficient, alkali etchability and film formability.

Abstract: A process for production of polyimide powder, which comprises reacting a biphenyltetracarboxylic dianhydride and an aromatic diamine in an amide-based solvent optionally containing a water-soluble ketone, in the presence of an imidazole at 1-100 equivalent percent based on the carboxylic acid content of the polyimide precursor, separating and collecting the produced polyimide precursor powder from a water-soluble ketone solvent containing 3-30 wt % of an amide-based solvent, and heating the polyimide precursor powder to an imidation rate of 90% or greater, as well as polyimide powder obtained thereby, molded bodies of the polyimide powder, and a process for production of the molded bodies.

Abstract: The object of the present invention is to provide a method capable of producing polyimide resins having excellent heat resistance, which can utilize inexpensive monomers and does not use solvents. The method comprises mixing, in the absence of a solvent, a diamine and at least one tetracarboxylic acid component selected from the group consisting of a tetracarboxylic acid, a tetracarboxylic acid monoanhydride and a tetracarboxylic acid dianhydride capable of forming two imide rings upon cyclization, and then heat-treating the mixture.

Abstract: A process for production of polyimide powder, which comprises reacting an aromatic diamine with a partial ester of a biphenyltetracarboxylic dianhydride, which is a partial ester of a biphenyltetracarboxylic dianhydride with a primary alcohol of 1-5 carbon atoms of which at least 30 mole percent is a 2,3,3′,4′-biphenyltetracarboxylic acid component, in the presence of the primary alcohol, separating out and collecting the resulting solid polyimide precursor and heating for dehydrating ring closure, polyimide powder obtained thereby, molded bodies of the polyimide powder, and a process for production of the molded bodies.

Abstract: This invention provides crosslinkable-group-containing polyimides of various known thermoplastic polyimide backbone structures, which are provided with far better heat resistance, chemical resistance and mechanical properties than known polyimides of the structures without impairing excellent moldability or formability, superb sliding property, low water absorption property, outstanding electrical properties, high thermal oxidation stability and high radiation resistance, all of which are inherent to the structures.

Abstract: A novel dielectric composition is provided that is useful in the manufacture of integrated circuit devices and integrated circuit packaging devices. The dielectric composition is prepared by imidizing and curing an oligomeric precursor compound comprised of a central polybenzoxazole, polybenzothiazole, polyamic acid or polyamic acid ester segment end-capped at each terminus with an aryl-substituted acetylene moiety such as an ortho-bis(arylethynyl)aryl group, e.g., 3,4-bis(phenylethynyl)phenyl. Integrated circuit devices, integrated circuit packaging devices, and methods of synthesis and manufacture are provided as well.

Abstract: The present invention relates to a novel polyimide of the general formula (1) and a process for the preparation thereof.

Abstract: A method for the synthesis of high molecular weight poly(imide)s comprising coupling poly(imide) precursors having complementary functional groups and a weight average molecular weight of less than about 50,000 Daltons to form high molecular weight poly (imides)s having a weight average molecular weight greater than 50,000 Daltons.

Abstract: The present invention provides a polymer in which coumarin, a photo-reactive molecule, is grafted onto a polyimide for preparing liquid crystal alignment layer which has a superior alignment property and an excellent thermal stability in photo-alignment, a process for preparing the said grafted polymer, a process for preparing liquid crystal alignment layer by employing the said grafted polymer, and a liquid crystal alignment layer prepared by the process. The polymer of the invention is prepared by mixing a coumarin compound with a polyimide, dissolving the mixture in an organic solvent, adding a catalyst, and stirring under an environment of N2 gas. The polymer of the invention is superior in terms of the thermal stability, which makes possible its universal application for the development of a novel liquid crystal display(LCD).