Abstract: A polyimide demonstrates low coefficient of hygroscopic expansion and low water absorption coefficient when used as an insulation film. The polyimide is derived from a tetracarboxylic acid dianhydride containing ester group expressed by the general formula below, and a polyester imide precursor: wherein R is independent and represents a straight or branched-chain alkyl group with 1 to 6 carbon atoms or straight or branched-chain alkoxyl group with 1 to 6 carbon atoms, n is an integer of 0 to 4, and m is an integer of 2 to 4, but wherein, if m =2, n is an integer of 1 to 4.

Abstract: The epoxy resin molding material of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the (B) curing agent contains a polyvalent carboxylic acid condensate. The thermosetting resin composition of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the viscosity of the (B) curing agent is 1.0-1000 mPa·s at 150° C., as measured with an ICI cone-plate Brookfield viscometer.

Abstract: A material for an optical film including a compound represented by Chemical Formula 1; a polymer including a repeating unit represented by Chemical Formula 10; a polymer including a repeating unit represented by Chemical Formula 20 and a repeating unit represented by Chemical Formula 21; an article prepared by using the polymer; and a display device including the article:

Abstract: Disclosed is a polyesterimide having a repeating unit expressed by the formula below, and also provides the manufacturing methods thereof: wherein R represents a phenyl group, R1 represents an alkyl group with 1 to 6 carbon atoms or alkoxy group with 1 to 6 carbon atoms, n each independently takes a value of 0 to 4, a each independently takes a value of 0 to 4, and m represents an integer of 2 to 4, where not all n's are 0 at the same time and 0?n+a?4 is satisfied by each phenylene group, and X is a divalent aromatic group and/or aliphatic group.

Abstract: The epoxy resin molding material of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the (B) curing agent contains a polyvalent carboxylic acid condensate. The thermosetting resin composition of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the viscosity of the (B) curing agent is 1.0-1000 mPa·s at 150° C., as measured with an ICI cone-plate Brookfield viscometer.

Abstract: The epoxy resin molding material of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the (B) curing agent contains a polyvalent carboxylic acid condensate. The thermosetting resin composition of the invention comprises (A) an epoxy resin and (B) a curing agent, wherein the viscosity of the (B) curing agent is 1.0-1000 mPa·s at 150° C., as measured with an ICI cone-plate Brookfield viscometer.

Abstract: The present invention provides a useful and novel alicyclic polyesterimide. An alicyclic polyesterimide produced by imidation of an alicyclic polyesterimide precursor is found to be a useful material in industrial fields, the alicyclic polyesterimide precursor being obtained by reacting an alicyclic tetracarboxylic anhydride having an ester group or a class of tetracarboxylic acid thereof as a starting material with an amine.

Abstract: Provided are a polyimide that demonstrates low coefficient of hygroscopic expansion and low water absorption coefficient when used as an insulation film, as well as an ester group-containing tetracarboxylic acid dianhydride expressed by the general formula below, and a novel polyesterimide precursor derived therefrom and polyesterimide, for use in the production of such polyimide: In the formula, each R is independent and represents a straight or branched-chain alkyl group with 1 to 6 carbon atoms or straight or branched-chain alkoxyl group with 1 to 6 carbon atoms, n is an integer of 0 to 4, and m is an integer of 2 to 4, with the proviso that if m=2, n is an integer of 1 to 4.

Abstract: The present invention relates to a deuterated polyimide, the backbone of which comprises an alternation between: at least one repeat unit corresponding to the following formula (I): in which: Y represents a single bond or a spacer group; and at least one repeat unit corresponding to the following formula (II): -A1-Z-??(II) in which: A1 represents a perdeuterated aromatic group comprising from 6 to 10 carbon atoms; Z represents a single bond or a group chosen from —O—C6D4—, —CO—C6D4— and —C6D4—. These polyimides are used in particular as materials which are transparent within the region from 2500 to 3500 cm?1, for example in laser devices.

Abstract: To provide a process for producing BPDA whereby high productivity is attained while high purity is maintained. A process for producing biphenyltetracarboxylic acid dianhydride, which comprises heating biphenyltetracarboxylic acid to produce biphenyltetracarboxylic acid dianhydride, characterized in that the heating is carried out at a pressure of from 1×102 Pa to 1.1×105 Pa to a maximum temperature in a range of from 210° C. to 250° C. in such a manner that the temperature rising rate is higher than 50° C./hr for a period of at least ¼0 of the time for the temperature rise from 60° C. to 210° C., and the temperature is maintained to be from 150° C. to 250° C. for from 0.5 to 10 hours.

Abstract: Disclosed are novel bicyclic tris(anhydride)s useful as intermediates in the synthesis of biologically active compounds, and the compounds which may be synthesized from such intermediates.

Abstract: Novel polyimides substituted by a substituent having an alkyl or fluoroalkyl group and having reduced water absorption; a process for producing these novel polyimides; and novel acid dianhydrides to be used in the production thereof. A polyimide containing a structure represented by the following general formula (I): wherein X1 represents a tetravalent organic group having a substituent —R1AR2 (wherein A represents a divalent linkage group; R1 represents a single bond or a C1-3 alkylene group; and R2 represents a C1-25 alkyl group or a fluoroalkyl group); and Y represents a divalent organic group.

Abstract: The present invention relates to compounds of formula I and II which are pyran-2-ones, 5,6-dihydro-pyran-2-ones, 4-hydroxy-benzopyran-2-ones, 4-hydroxy-cycloalkyl[b]pyran-2-ones, and derivatives thereof, useful for inhibiting a retrovirus in a mammalian cell infected with said retrovirus.

Abstract: Disclosed herein are novel poly(imide-ethers) containing ortho substitution in the main chain of the polymer. These polymers are made from novel aromatic bis-carboxylic anhydrides which contain two ether groups attached to an aromatic ring in ortho positions to each other. The polymers are particularly useful for films, fibers and encapsulation, as well as thermoplastics.

Abstract: Anhydride compounds which contain at least one rodlike mesogenic moiety and at least two anhydride groups per molecule, wherein each of said aromatic anhydride groups is linked to the mesogen via an ester linkage are prepared. These anhydride compounds are useful in curing epoxy resins to provide the cured products with one or more improved properties.

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;=methallyl or allyl;Me=methyl;R.sub.2 =a trivalent organic radical; andR.sub.3 =a divalent organic radical.The amideimde 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: Aromatic trisanhydrides of the formula (I) ##STR1## wherein R is hydrogen, C.sub.1 -C.sub.4 alkyl or aryl are useful for the synthesis of star-branched and star-burst polyester-imides and polyesterimide-amides and as curing agents for epoxy resins, phenolics and polyesters.

Abstract: Aromatic trisanhydrides of the formula (I) ##STR1## wherein R is hydrogen, C.sub.1 -C.sub.4 alkyl or aryl are useful for the synthesis of star-branched and star-burst polyester-imides and polyesterimide-amides and as curing agents for epoxy resins, phenolics and polyesters.

Abstract: A method for reducing the formation of dust produced by solid aromatic anhydrides, and aromatic anhydride compositions that have a reduced tendency to emit aromatic anhydride dust, are disclosed. The method comprises treating the aromatic anhydride with low levels of suitable organic compounds.

Abstract: The invention relates to the preparation of novel dianhydrides of the formula: ##STR1## wherein R is a polyalkylated mononuclear aromatic radical, preferably a phenylene radical. The mononuclear aromatic radical may be substituted with from three to four lower alkyl radicals, preferably C.sub.1 -C.sub.4 alkyl radicals. The dianhydrides are preferably made by the reaction of a monoanhydride monoacid halide and a polyalkylated mononuclear aromatic in the presence of a Friedel-Crafts catalyst under Friedel-Crafts reaction conditions. These dianhydrides ae useful reactants in the preparation of polyimides and epoxy curing agents.

Abstract: Aromatic tetracarboxylic acids or derivatives thereof of the general formula I ##STR1## in which R denotes a divalent radical of the formula II ##STR2## Ar denotes tri- or tetravalent aromatic radicals or mixtures thereof, X, if Ar is trivalent, denotes an amide radical, and if Ar is tetravalent denotes an imide radical, and Y and Z either together denote the anhydride radical --CO--O--CO-- or by themselves and independently of one another denote the radicals --COOH, --COCL or --COOR.sub.1, and a process for their preparation.

Abstract: Aromatic dianhydrides being substituted in the positions ortho to the bridging moiety, said substituent groups including halogen, alkyl, hydroxy, nitro, cyano, ester, alkoxy, perfluoroalkyl, mercapto and thioester groups, said dianhydrides providing certain beneficial properties to polyimides prepared therefrom.

Abstract: A process for production of 2,6-dimethylnaphthalene is disclosed; comprising the steps: (1) an acylation step where 2,4-dimethylisobutyrophenone is produced from m-xylene, propylene and carbon monoxide: (2) a hydrogenation step where the carbonyl group of the above 2,4-dimethylisobutyrophenone is hydrogenated: and (3) a dehydrogenation and cyclization step where the above hydrogenated product is subjected to dehydrogenation and cyclization to produce the desired 2,6-dimethylnaphthalene. The process enables efficiently producing high quality or high purity 2,6-dimethylnaphthalene.

Abstract: A process for production of 2,6-dimethylnaphthalene is disclosed, comprising the steps: (1) an acylation step where p-tolyl sec-butyl ketone is produced from toluene, n-butene and carbon monoxide: (2) a hydrogenation step where the carbonyl group of the p-tolyl sec-butyl ketone is hydrogenated: and (3) a dehydrogenation and cyclization step where the hydrogenated product obtained above is subjected to dehydrogenation and cyclization to produce the desired 2,6-dimethylnaphthalene. The process enables efficiently producing a high quality or high purity 2,6-dimethylnaphthalene.

Abstract: Process for the purification of organic polyanhydrides to substantially-completely remove trace metals, such as for the production of metal-free electronic grade polymers. The process comprises decyclizing in an aqueous vehicle to form the polyacid, treating with an adsorption agent, crystallizing the polyacid, filtering and reconverting to the polyanhydride which is substantially free of trace metals. The purified polyanhydride can be reacted with other metal-free monomers to form metal-free polymers having excellent insulating properties for use in electrical components.

Abstract: A process for producing benzophenone tetracarboxylic dianhydride, which comprises adding benzophenone tetracarboxylic acid to a solvent comprising, as the main constituent, an organic compound having a boiling point of more than 100.degree. C. and being inert to benzophenone tetracarboxylic acid and benzophenone tetracarboxylic anhydrides, and heating the resulting mixture. This process enables one to produce benzophenone tetracarboxylic dianhydride having a very low moisture absorbency.

Abstract: A water soluble composition including an amine or ammonium salt of a polyimide precursor which is obtained by the reaction steps of: reacting a tetracarboxylic compound and a diamine in about equimolar amounts in a water miscible organic solvent to obtain the polyimide precursor; and reacting the polyimide precursor with ammonia, or an aqueous solution of ammonia, or a primary or secondary aliphatic amine in an amount sufficient to neutralize the free carboxyl groups of the polyimide precursor.A process of coating and a substrate are also disclosed.

Abstract: A method of preparation and/or purification of acid anhydrides is disclosed. Dicarboxylic or polycarboxylic acids contained in the anhydrides to be treated, are dehydrated in an organic solvent in the presence of activated carbon.