Abstract: Polyester polyols, processes for making them, and applications for the polyols are disclosed. Some of the polyols comprise recurring units from a digested thermoplastic polyester (e.g., recycled polyethylene terephthalate), a diol, an optional hydrophobe, and a clarifier. The clarifier, which in some cases is a bisphenol, bisphenol alkoxylate, bisphenol polycarbonate, sulfonyl diphenol, or sulfonyl diphenol alkoxylate, helps the polyol remain clear for weeks or months after its preparation. In some aspects, the clarifier is a monophenol, bisphenol, or poly-phenol having two or more phenylene rings wherein at least two of the phenylene rings lack a common molecular axis. The clarifier may also be an alkylated phenol, an epoxy resin, an epoxy novolac resin, a diphenylmethane, or a tris(aryloxy)phosphate.

Abstract: Porous cross-linked polyimide-urea networks are provided. The networks comprise a subunit comprising two anhydride end-capped polyamic acid oligomers in direct connection via a urea linkage. The oligomers (a) each comprise a repeating unit of a dianhydride and a diamine and a terminal anhydride group and (b) are formulated with 2 to 15 of the repeating units. The subunit was formed by reaction of the diamine and a diisocyanate to form a diamine-urea linkage-diamine group, followed by reaction of the diamine-urea linkage-diamine group with the dianhydride and the diamine to form the subunit. The subunit has been cross-linked via a cross-linking agent, comprising three or more amine groups, at a balanced stoichiometry of the amine groups to the terminal anhydride groups. The subunit has been chemically imidized to yield the porous cross-linked polyimide-urea network. Also provided are wet gels, aerogels, and thin films comprising the networks, and methods of making the networks.

Abstract: A polyetherimide manufactured by reaction of an alkali metal salt of a dihydroxy aromatic compound of the formula MO—Z—OM wherein M is an alkali metal salt and Z is an aromatic C6-24 monocyclic or polycyclic moiety optionally substituted with 1 to 6 C1-8 alkyl groups, 1 to 8 halogen atoms, or a combination thereof, with a bis(halophthalimide) composition comprising, based on the weight of the bis(halophthalimide) composition, from more than 45 to less than 75 weight percent of a 3,3?-bis(halophthalimide) of the formula less than 10 weight percent of a 3,4?-bis(halophthalimide) of the formula and from more than 45 to less than 75 weight percent of a (4,4?-bis(halophthalimide) of the formula

Abstract: Provided are cardo copolybenzimidazoles, a gas separation membrane using the same and a method for preparing the same. More particularly, provided are cardo copolybenzimidazoles obtained by introducing cardo groups and aromatic ether groups to a polybenzimidazole backbone, a gas separation membrane having significantly improved oxygen permeability by using the same, and a method for preparing the same. The cardo copolybenzimidazoles have improved solubility as compared to the polybenzimidazole polymers according to the related art, show excellent mechanical properties while maintaining thermal stability so as to be formed into a film shape, and provide a gas separation membrane having significantly improved gas permeability, particularly, oxygen permeability.

Abstract: A method of forming a polyimide film on a surface of a substrate by dehydration condensation of a first monomer including a bifunctional acid anhydride and a second monomer including a bifunctional amine is disclosed. The method includes loading the substrate into a processing chamber, heating the substrate at a temperature at which a polyimide film is formed, and performing a cycle a predetermined number of times. The cycle comprises supplying a first processing gas containing the first monomer to the substrate, supplying a second processing gas containing the second monomer to the substrate. The method further includes supplying a replacement gas in the processing chamber between supplying the first processing gas and supplying the second processing gas thereby replacing atmosphere in the processing chamber by the replacement gas, and evacuating the first and/or the second processing gas out of the processing chamber.

Abstract: A crosslinkable aromatic polyester that is formed by polymerizing certain precursor monomers in the presence of a biaromatic crosslinking agent is provided. The crosslinkable aromatic polyester can have a relatively high melting temperature. For example, the melting temperature of the crosslinkable polyester may be from about 200° C. to about 370° C. While having a relatively high melting temperature, the crosslinkable polyester can maintain a relatively low melt viscosity so that it can be readily removed from the polymerization reactor without solidifying therein.

Abstract: The present invention relates to an obtainment process of biodegradable polymers from a citric residue resulting from the processing of orange juice. The polymers obtained are polyesters classified as polyhydroxyalkanoates including, among them the poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate). The biodegradable polymer is obtained from the batch culture process or fed batch culture process with or without recirculation of the cells, using as a carbon source the pre-treated pressing liquor and/or the citric molasses. The polyhydroxyalkanoates, herein described, can be used as substitutes of the synthetic polyesters in different areas, including the food, pharmaceutical, medical, agricultural and other areas.

Abstract: The invention provides new aliphatic diester-di-acid-containing PEA polymer compositions with significant improvement in hydrolytic degradation rates as compared to aliphatic di-acid-containing PEA polymers. The di-acids used in the invention PEA compositions include non-toxic fatty aliphatic homologs. These molecules inherently contain two-ester groups, which easily can be cleaved by biotic (enzymatic) and abiotic hydrolysis. Additional di-acid-type compounds useful for active polycondensation are ?,?-alkylene dicarboxylates composed of short aliphatic non toxic diols and di-acids. In addition, the invention PEA polymer compositions optionally can include a second monomer, such as a C-protected L-lysine-based monomer, to introduce additional chain flexibility into the polymer. The invention PEA polymer compositions are useful for delivery of bioactive agents when administered internally.

Abstract: This invention relates to compositions, and the use of such compositions for protective coatings, particularly of electronic devices. The invention concerns fired-on-foil ceramic capacitors coated with a composite encapsulant and embedded in a printed wiring board.

Abstract: A method for forming a polyimide composite article utilizes a polyimide resin system including at least a first prepolymer component and a second prepolymer component. A preform structure is tackified with the first prepolymer component. Using resin infusion or resin transfer molding techniques, the tackified preform structure is contacted with the second prepolymer component. The polyimide resin system is cured under suitable cure conditions so that the first and second prepolymer components mix and react to produce the polyimide composite structure.

Abstract: The benefits of liquid crystal polymers and polyetherimides are combined in an all-aromatic thermoplastic liquid crystalline polyetherimide. Because of the unique molecular structure, all-aromatic thermotropic liquid crystal polymers exhibit outstanding processing properties, excellent barrier properties, low solubilities and low coefficients of thermal expansion in the processing direction. These characteristics are combined with the strength, thermal, and radiation stability of polyetherimides.

Abstract: A polyester resin and a fabrication method thereof are provided. The fabrication method includes providing a diphenol monomer and a diacid monomer. The diphenol monomer is acetylated and then melt pre-polymerized with diacid monomer to form a pre-polymer. Then, the pre-polymer is polymerized by solid state polymerization to form a heat-resistant and transparent polyester resin.

Abstract: The present invention provides wound dressings, optionally surgically implantable, containing biodegradable, polymers and hydrogels having allogenic or autologous precursor cells, such as stem cells and progenitor cells dispersed within. Alternatively, the wound dressings can have conditioned medium obtained from the precursor cells dispersed within. The wound dressings promote tissue restoration processes at a site of application or implantation. Additional bioactive agents can also be dispersed within the polymer/hydrogel matrix, which can be formulated to biodegrade at a controlled rate by adjusting the composition. Methods are also provided for using such biodegradable wound dressings as a delivery device or carrier for the precursor cells, conditioned medium and bioactive agents, or as coatings on implantable medical devices, to promote tissue restoration at a lesion site.

Abstract: A polyester resin and a fabrication method thereof are provided. The fabrication method includes providing a diphenol monomer and a diacid monomer. The diphenol monomer is acetylated and then melt pre-polymerized with diacid monomer to form a pre-polymer. Then, the pre-polymer is polymerized by solid state polymerization to form a heat-resistant and transparent polyester resin.

Abstract: The present invention relates to a process for preparing polyarylate, and more specifically, to a process for preparing polyarylate by interfacial polymerization of a bivalent phenol compound and an aromatic dicarboxylic acid or a halide thereof, which comprises mixing a cationic catalyst for the phase transition and a nonionic surfactant in a predetermined ratio, to further increase the yield of polyarylate, as compared with the case of using each of the nonionic surfactant and the cationic catalyst for the phase transition alone.

Abstract: Copolyetherimides compositions having high glass transition temperatures and outstanding ductility are presented. The copolyetherimides having Mw of at least 40,000 comprising isomeric bis(phthalimide) structural units within a relatively narrow range of isomer proportions exhibited Tgs of at least 240° C. and outstanding Notched Izod values. The copolyetherimides comprise oxydianiline residues and structural units of the formulas (I) and (II) (III).

Abstract: A polymer electrolyte membrane comprising a microporous polymer membrane having pores penetrating through the opposite sides thereof. The microporous polymer membrane holds a mixture of a polymer and a molten salt at a weight ratio of 1/99 to 99/1 and/or a molten salt. The polymer electrolyte membrane is inexpensive, durable, excellent in mechanical strength, excellent in structural retention in high temperatures, and capable of stably holding a molten salt in its porous polymer membrane structure, shows high heat resistance, and secures high ionic conductivity in the absence of water or a solvent and is therefore useful in fuel cells, secondary batteries, electric double layer capacitors, electrolytic capacitors, and the like.

Abstract: Provided herein are a phenolic hydroxyl group-containing aromatic polyamide resin and a resin composition containing the resin, such as an epoxy resin composition containing an epoxy resin. The phenolic hydroxyl group-containing aromatic polyamide resin has a structure represented by the following formula (1): wherein m and n are average values satisfying the following formula: 0.005?n/(m+n)<0.05, m+n is a positive value of 2 to 200, Ar1 is a bivalent aromatic group, Ar2 is a phenolic hydroxyl group-containing bivalent aromatic group, and Ar3 is a bivalent aromatic group. Such a phenolic hydroxyl group-containing aromatic polyamide resin has a low ionic impurity content and improved adhesive properties as well as excellent properties inherent in conventional phenolic hydroxyl group-containing aromatic polyamide resins, such as the ability to allow a cured epoxy resin composition to have excellent flexibility, electrical properties, flame retardancy, and the like.

Abstract: A promoter for a polycondensation reaction used together with a catalyst in a polycondensation reaction, the promoter for a polycondensation reaction comprising a pyrogallol compound having a benzene ring of which three hydrogen atoms adjacent to each other are substituted by hydroxyl groups; and a polycondensation resin obtained by polycondensing raw material monomers using the promoter as defined above and the catalyst. A polycondensation resin can be produced using the promoter of the present invention together with a catalyst in a polycondensation reaction, and the polycondensation resin can be used in various applications including, for example, films, sheets, fibers, toner materials for electrophotography, and the like.

Abstract: The invention provides elastomeric copolyester amides, elastomeric copolyester urethanes, and methods for making the same. The polymers are based on ?-amino acids and possess physical, chemical and biodegradation properties that render them suitable for use in the human body. The polymers are useful as carriers of drugs or other bioactive substances. The polymers can also be linked, intermixed, or a combination thereof, to one or more drugs. Additionally, the polymers can be used to coat stents, for example, to suppress restenosis. Furthermore, the biodegradation of the copolyester amides and copolyester urethanes allows for the delivery of essential ?-amino acids to sites in the body, for example, to facilitate wound repair of injured tissues.

Abstract: A process for preparing polyarylate wherein a bivalent phenol compound having the structure of Formula 1 and an aromatic dicarboxylic acid halogen compound react to prepare a polyarylate, and wherein a nonionic surface-active agent is added. This decreases residual salts and improves the transmittance and the heat-resistance. In Formula 1, R1, R2, R3 and R4 denote the same as illustrated in the description.

Abstract: A method is provided for reducing the color generated during production of copolycarbonate that includes quinone-type residues. The method includes the steps preparing a reaction mixture containing precursors of monomer residues, selecting a catalyst, introduction strategy and adding catalysts according to the strategy. The strategy is sufficient to result in a product copolycarbonate with improved color. The method further includes the steps of introducing the reaction mixture to a series of process units and allowing the reaction mixture to polymerize thereby forming a copolycarbonate. The resulting copolycarbonate has improved color as compared to a copolycarbonate formed in a process without the steps of selecting a catalyst introduction strategy and introducing catalysts according to the selected strategy.

Abstract: The present invention provides elastomeric copolyester amides, elastomeric copolyester urethanes, and methods for making the same. The polymers that are based on ?-amino acids and possess suitable physical, chemical and biodegradation properties. The polymers are useful as carriers of drugs or other bioactive substances. The polymers can be linked, intermixed, or a combination thereof, to one or more drugs.

Abstract: A thermoplastic composition includes a functionalized poly(arylene ether) and a copolymer of (a) ethylene or an ?-olefin, and (b) an alkyl(meth)acrylate. Optional components in the composition include an impact modifier and a flame retardant. The composition is useful for fabricating wire and cable insulation.

Abstract: A diamine compound represented by the formula (1): wherein R1 is a trivalent organic group, each of X1 and X2 is a bivalent organic group, X3 is an alkyl or fluoroalkyl group having from 1 to 22 carbon atoms, or a cyclic substituent selected from aromatic rings, aliphatic rings, heterocyclic rings and their substituted groups, and n is an integer of from 2 to 5. And, a polyimide precursor and a polyimide synthesized by using the diamine compound; and a treating agent for liquid crystal alignment containing the polyimide precursor and/or the polyimide.

Abstract: A method for preparation of a sulfonic and or sulfonic acid salt containing polyimide resins comprising melt reaction of a polyimide resin with an organic compound, wherein the organic compound contains at least one aliphatic primary amine functionality and at least one other functionality selected from the group consisting of sulfonic acids, sulfonic acid salts or mixtures thereof.

Abstract: The invention provides a polyhydroxyalkanoate having a bromo group in a unit and being thermally stable and capable of arbitrarily controlling physical properties, and a producing method thereof. According to the invention, there are provided a polyhydroxyalkanoate copolymer including a 3-hydroxy-?-bromoalkanoic acid unit represented by a formula—[OCH((CH2)nBr)CH2C(O)]— (n=1 to 8) (1) and a unit represented by a formula —[OCH((CH2)mR)CH2C(O)]— (2) within a same molecule, and a method for producing a polyhydroxyalkanoate copolymer by microorganisms, utilizing a ?-bromoalkanoic acid represented by a formula Br(CH2)pCH2CH2COOH (p=1 to 8) (20) and a compound represented by a formula R(CH2)qCH2CH2COOH (21) as raw materials.

Abstract: Polyimide resins that are suitable for processing by resin transfer molding (RTM) and resin infusion (RI) methods at reduced processing temperatures are provided. The inventive RTM and RI processable polyimide resins exhibit melting at temperatures of less than about 200° C. and melt viscosities at 200° C. of less than about 3000 centipoise. A process for synthesizing the inventive resins is also provided, as is a fiber-reinforced composite material. The fiber-reinforced composite material employs the inventive polyimide resin as its resin matrix and demonstrates good heat resistance and mechanical properties.

Abstract: A material for dielectric films is a polymerizable composition containing an adamantanepolycarboxylic acid represented by following Formula (1): wherein X is a hydrogen atom, a carboxyl group or a hydrocarbon group; and Y1, Y2, Y3 and Y4 are the same as or different from one another and are each a single bond or a bivalent aromatic cyclic group; an aromatic polyamine represented by following Formula (2): wherein Ring Z is a monocyclic or polycyclic aromatic ring; and R1 and R2 are each a substituent bound to Ring Z, are the same as or different from each other and are each an amino group, a mono-substituted amino group, a hydroxyl group or a mercapto group; and a solvent other than ketones and aldehydes, in which the adamantanepolycarboxylic acid and aromatic polyamine are dissolved in the solvent

Abstract: In the process of the present invention, a solvent-soluble polyimide is produced by polycondensing at least one tetracarboxylic acid component with at least one diamine component in a solvent in the presence of a tertiary amine. The tetracarboxylic acid component is selected from the group consisting of tetracarboxylic dianhydrides represented by the following formula 1: wherein R is as defined in the specification, and tetracarboxylic acids and their derivatives represented by the following formula 2: wherein R and Y1 to Y4 are as defined in the specification. Unlike the conventional techniques using an excessively large amount of a chemical imidation agent such as acetic anhydride and a chemical imidation catalyst such as triethylamine, in the process of the present invention, the solvent-soluble polyimide having a high polymerization degree is easily produced in a solvent with good productivity by using only a catalytic amount of the tertiary amine.

Abstract: The present invention provides a polyimide resin for an electrical insulating material which comprises a polyimide resin having a repeating unit represented by general formula (I): wherein R1 represents a bivalent organic group.

Abstract: A preparation process of polyimide aerogels that composed of aromatic dianhydrides and aromatic diamines or a combined aromatic and aliphatic diamines is described. Also descried is a process to produce carbon aerogels derived from polyimide aerogel composed of a rigid aromatic diamine and an aromatic dianhydride. Finally, the processes to produce carbon aerogels or xerogel-aerogel hybrid, both of which impregnated with highly dispersed transition metal clusters, and metal carbide aerogels, deriving from the polyimide aerogels composed of a rigid aromatic diamine and an aromatic dianhydride, are described. The polyimide aerogels and the polyimide aerogel derivatives consist of interconnecting mesopores with average pore size at 10 to 30 nm and a mono-dispersed pore size distribution. The gel density could be as low as 0.008 g/cc and accessible surface area as high as 1300 m2/g.

Abstract: The invention relates to an enzymatic-chemical method for obtaining polyhydroxyalkanoates (PHA), especially polyhydroxybutyrate (PHB), or the copolymers thereof, from biomass. The inventive method comprises chemically treating the biomass with a reducing agent that reduces the non-PHA cell components of the biomass. The chemical treatment is carried out before and/or after enzymatic cell disruption. The inventive method allows, unlike other cell disruption techniques, for obtaining polyhydroxyalkanoates from biomass with a relatively low PHA content (for example <60%) without drastically changing or deteriorating the polymer properties or polymer purity.

Abstract: Disclosed herein are polyetherimide compositions comprising structural units of the formula: derived from at least one benzimidazole diamine, wherein R1 and R2 are independently selected from hydrogen and C1–C6 alkyl groups; “A” comprises structural units of the formulae: or mixtures of the foregoing structural units; wherein “D” is a divalent aromatic group, R3 and R10–R12 are independently selected from hydrogen, halogen, and C1–C6 alkyl groups; “q” is an integer having a value of 1 up to the number of positions available on the aromatic ring for substitution; and “W” is a linking group; and “B” comprises substituted and unsubstituted arylene groups having from about 6 to about 25 carbon atoms. Methods for producing the polyetherimide compositions are also disclosed herein.

Abstract: The present invention relates to a polyimide adhesive composition having a polyimide derived from an aromatic dianhydride and a diamine component, where the diamine component is preferably about 50 to 90 mole % of an aliphatic diamine and about 10 to 50 mole % of an aromatic diamine. In one embodiment, the aliphatic diamine has the structural formula H2N—R—NH2 wherein R is hydrocarbon from C4 to C16 and the polyimide adhesive has a glass transition temperature in the range of from 150° C. to 200° C. The present invention also relates to compositions comprising the polyimide adhesive of the present invention, including polyimide metal-clad laminate useful as flexible circuit when metal traces are formed out of the metal used in flexible, rigid, or flex-rigid circuit applications.

Abstract: A new class of hybrid organic-inorganic materials, and methods of synthesis, that can be used as a proton exchange membrane in a direct methanol fuel cell. In contrast with Nafion® PEM materials, which have random sulfonation, the new class of materials have ordered sulfonation achieved through self-assembly of alternating polyimide segments of different molecular weights comprising, for example, highly sulfonated hydrophilic PDA-DASA polyimide segment alternating with an unsulfonated hydrophobic 6FDA-DAS polyimide segment. An inorganic phase, e.g., 0.5–5 wt % TEOS, can be incorporated in the sulfonated polyimide copolymer to further improve its properties. The new materials exhibit reduced swelling when exposed to water, increased thermal stability, and decreased O2 and H2 gas permeability, while retaining proton conductivities similar to Nafion®. These improved properties may allow direct methanol fuel cells to operate at higher temperatures and with higher efficiencies due to reduced methanol crossover.

Abstract: A terminal-crosslinkable polyamic acid oligomer having 1) heat resistance indicated by Tg of 300° C. or more and a pyrolysis temperature of 500° C. or more, 2) toughness, and 3) capability of allowing an increase in concentration. The polyamic acid oligomer is obtained by reacting an aromatic tetracarboxylic dianhydride including 2,2?,3,3?-biphenyltetracarboxylic dianhydride, an aromatic diamine compound, and a reactive crosslinking agent including an amino group or acid anhydride group and a crosslinkable group in the molecule, and includes a crosslinkable group at the molecular terminal.

Abstract: This invention relates to the composition and a solvent-free process for preparing novel imide oligomers and polymers specifically formulated with effective amounts of a dianhydride such as 2,3,3?,4-biphenyltetra carboxylic dianydride (a-BPDA), at least one aromatic diamine and an endcapped of 4-phenylethynylphthalic anhydride (PEPA) or nadic anhydride to produce imide oligomers that possess a low-melt viscosity of 1–60 poise at 260–280° C. When the imide oligomer melt is cured at about 371° C. in a press or autoclave under 100–500 psi, the melt resulted in a thermoset polyimide having a glass transition temperature (Tg) equal to and above 310° C. A novel feature of this process is that the monomers; namely the dianhydrides, diamines and the endcaps, are melt processable to form imide oligomers at temperatures ranging between 232–280° C. (450–535° F.) without any solvent.

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: The substrates of the present invention comprise a polyimide base polymer derived at least in part from collinear monomers together with crankshaft monomers. The resulting polyimide material has been found to provide advantageous properties, particularly for electronics type applications.

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: 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 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: This invention relates to the composition and a solvent-free process for preparing novel imide oligomers and polymers specifically formulated with effective amounts of a dianhydride such as 2,3,3?,4-biphenyltetra carboxylic dianydride (a-BPDA), at least one aromatic diamine and an endcapped of 4-phenylethynylphthalic anhydride (PEPA) or nadic anhydride to produce imide oligomers that possess a low-melt viscosity of 1-60 poise at 260-280° C. When the imide oligomer melt is cured at about 371° C. in a press or autoclave under 100-500 psi, the melt resulted in a thermoset polyimide having a glass transition temperature (Tg) equal to and above 310° C. A novel feature of this process is that the monomers; namely the dianhydrides, diamines and the endcaps, are melt processable to form imide oligomers at temperatures ranging between 232-280° C. (450-535° F.) without any solvent.