Abstract: A process includes the steps of: casting or coating a polyamic acid organic solvent solution on a support and drying the polyamic acid organic solvent solution thereon, so as to form a partially cured and/or partially dried polyamic acid film; dipping the polyamic acid film in tertiary amine or a solution of tertiary amine, or coating tertiary amine or a solution of tertiary amine on the polyamic acid film; and drying the film while imidizing the polyamic acid. In another process, a chemical converting agent and a catalyst are mixed in an organic solvent solution of polyamic acid. After casting and heating the mixture on a support, a partially cured and/or partially dried polyamic acid film is detached from the support. The film contains, with respect to the remaining volatile component, not less than 50 parts of catalyst, not more than 30 parts of solvent, and not more than 20 parts of chemical converting agent and/or a chemical converting agent derived component.

Abstract: Provided are composite material comprising hollow glass microspheres and a microcellular thermoplastic resin, articles molded from such materials, and methods of making such materials.

Abstract: The present disclosure provides a method for producing an aerogel, the method comprising reacting at least one acid monomer with at least one diamino monomer in a first solvent under conditions appropriate to form a polyimide polymer; conducting a solvent exchange wherein the first solvent is exchanged for a second solvent, said second solvent having a freezing point, wherein said solvent exchange further comprises (1) submersing the polyimide polymer in the second solvent in a pressure vessel and (2) creating a high pressure environment inside the pressure vessel for a first period of time; cooling the polyimide polymer to a first temperature below the freezing point of the second solvent; and subjecting cooled polyimide polymer to a first vacuum for a second period of time at a second temperature.

Abstract: Polymers containing poly(ester amides) and agents for use with medical articles and methods of fabricating the same are disclosed. The medical article generally comprises an implantable substrate having a coating, and the coating contains a polymer comprising a polymeric product of a reaction comprising a polyol, a polycarboxylic acid, an amino acid and an agent.

Abstract: The present invention is related to a polymer resin composition capable of providing an insulating material having a low dielectric constant and excellent mechanical properties, a polyimide resin film obtained by using the polymer resin composition, a preparation method of a polyimide resin film, and a circuit board and a metal laminate including the polyimide resin film.

Abstract: The invention provides a non-particulate cross-linked poly-?-lysine polymer. The poly-?-lysine and cross linker are linked by amide bonds and may the cross linker has at least two functional groups capable of reacting with an alpha carbon amine of poly-?-lysine. The polymer is suitably insoluble in water and other solvents and is provided in macro form for example a sheet, article or fibre. The macro form polymer is useful in a wide range of applications including wound treatment, as a medical diagnostic comprising a particulate support and a functional material bound or retained by the support and solid phase synthesis of peptides, oligonucleotides, oligosaccharides, immobilisation of species, cell culturing and in chromatographic separation.

Abstract: Disclosed are polyimide short fibers having an extremely high heat resistance, suitable for non-woven fabrics and paper, and having many branches. Specifically, disclosed are polyimide short fibers having many branches, which are produced by beating and loosening a specific foamed polyimide material. The foamed material preferably comprises a polyimide produced using 2,3,3?,4?-biphenyltetracarboxylic acid as an aromatic tetracarboxylic acid component, preferably has a glass transition temperature of 300° C. or higher, and preferably has an expansion ratio of 20 times or more.

Abstract: Provided is a polyamide polymer in which a partial structure represented by the following formula (C) constitutes a portion of the main chain: wherein in Formula (C), RA and RB each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; n and m each independently represent an integer from 0 to 2; Cy represents an unsaturated 6-membered or 7-membered ring which may contain a heteroatom; and * and ** each represent a bonding hand, while * may be a bonding hand extending from RA.

Abstract: Provided is a polyamide polymer in which a partial structure represented by the following formula (C) constitutes a portion of the main chain: wherein in Formula (C), RA and RB each independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; n and m each independently represent an integer from 0 to 2; Cy represents an unsaturated 6-membered or 7-membered ring which may contain a heteroatom; and * and ** each represent a bonding hand, while * may be a bonding hand extending from RA.

Abstract: An organic aerogel includes a polymer prepared from a substituted or unsubstituted maleimide compound and a compound having at least two vinyl groups. A composition for the organic aerogel includes a substituted or unsubstituted maleimide compound and a compound having at least two vinyl groups.

Abstract: Disclosed herein is a method for making polyimide articles that are suitable for high temperature applications. The articles disclosed herein are rigid, oxidatively stable, wear-resistant, and permeable to heated moisture and gases, and comprise co-polymer based polyimide, and at least one additive or filler, and are made using 20,000 to 50,000 psi of compression pressure.

Abstract: Disclosed is a polyimide porous web with good porosity, good dimensional stability, and uniform pore; a method for manufacturing the same; and an electrolyte membrane with improved ion conductivity and good dimensional stability owing to ion conductors uniformly impregnated in the porous web, the polyimide porous web having a porosity of 60% to 90%, wherein not less than 80% of entire pores of the porous web have a pore diameter which differs from an average pore diameter of the porous web by not more than 1.5 ?m.

Abstract: Disclosed herein is a method for making polyimide articles that are suitable for high temperature applications. The articles disclosed herein are rigid, oxidatively stable, wear-resistant, and permeable to heated moisture and gases, and comprise co-polymer based polyimide, and at least one additive or filler, and are made using 20,000 to 50,000 psi of compression pressure.

Abstract: The present invention relates to a porous ABPBI (phosphoric acid doped poly(2,5-benzimidazole)) membrane and process of preparing the same. A stable porous ABPBI (Phosphoric Acid Doped Poly(2,5-benzimidazole)) membrane stable to acids, bases, solvents and autoclaving is disclosed.

Abstract: A 3-dimensional porous polymeric structure comprising a porous polymer structure optionally with particles within the pores of the polymer and wherein the pores have a narrow pore-size distribution. The structure may be made by closely packing particles in a zone to provide a 3-dimensional array, contacting a polymerisable monomer with the array such that the composition fills interstitial spaces between the particles and effecting polymerisation of the monomer whereby a polymer structure is formed around the particles and optionally removing the particles from the structure. The 3-dimensional porous structure may be used in solid phase synthesis, immobilisation, cell culturing and preparation of a stationary phase for chromatographic separation, as an absorbent, an insulating material or in tissue regeneration.

Abstract: Provided are methods of treating an open cell polyimide foam product to produce a treated polyimide foam product having a property of repelling water or oil. The method includes the steps of: selecting a polyimide foam product having an external surface area and an open cell structure that has an interior surface area, wetting the exterior surface area and the interior surface area with a chemical treatment fluid comprising a treatment chemical that has a property of repelling water or oil, and distributing the treatment chemical onto at least a portion of the interior surface area sufficient to modify a surface property of the interior surface. Also provided are treated polyimide foam products that have an open cell polyimide foam substrate with an interior surface area and a treatment chemical on at least a portion of the interior surface area. The treatment chemical renders the interior surface hydrophobic or oleophobic.

Abstract: A composition of and a method of making high performance crosslinked membranes are described. The membranes have a high resistance to plasticization by use of crosslinking. The preferred polymer material for the membrane is a polyimide polymer comprising covalently bonded ester crosslinks. The resultant membrane exhibits a high permeability of CO2 in combination with a high CO2/CH4selectivity. Another embodiment provides a method of making the membrane from a monesterified polymer followed by final crosslinking after the membrane is formed.

Abstract: The present invention relates to a method for preparing a porous polyimide film, comprising reacting an aromatic dianhydride with one or more aromatic diamines in a suitable solvent to form poly(amic acid), adding a dehydrated agent of an acid anhydride and an organic base to the reaction mixture to convert the poly(amic acid) to a polyimide precursor, casting the reaction mixture comprising the polyimide precursor onto a solid support to form a film, coagulating the polyimide precursor in a coagulating bath comprising a mixture of a solvent and a non-solvent to develop a porous structure, and drying the coagulated polyimide precursor in air to form the porous polyimide film. A composite membrane comprising same and its use are also provided.

Abstract: The present invention discloses a new type of high performance polymer membranes prepared from aromatic polyimide membranes by thermal treating and crosslinking and methods for making and using these membranes. The polymer membranes were prepared from aromatic polyimide membranes by thermal treating under inert atmosphere followed by crosslinking preferably by using a UV radiation source. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The membranes showed significantly improved selectivity and permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The membranes can be fabricated into any convenient geometry and are not only suitable for a variety of liquid, gas, and vapor separations, but also can be used for other applications such as for catalysis and fuel cell applications.

Abstract: Fibered particles combine microscale spheroid particles and nanoscale fibers in an integrated body. Fibered particles may be combined with a matrix precursor to form syntactic foams incorporating both particles and fibers.

Abstract: Disclosed is a polymer derived from polyamic acid or a polyimide. The polymer derived from polyamic acid or a polyimide includes picopores, and the polyamic acid and the polyimide include a repeating unit obtained from an aromatic diamine including at least one ortho-positioned functional group with respect to an amine group and a dianhydride.

Abstract: A porous polyimide obtained by removing a silica phase from an organic-inorganic polymer hybrid having a molecule structure in which a polyimide phase and the silica phase are held together by covalent bond.

Abstract: The invention involves composite materials containing a polymer foam and an aerogel. The composite materials have improved thermal insulation ability, good acoustic insulation, and excellent physical mechanical properties. The composite materials can be used, for instance, for heat and acoustic insulation on aircraft, spacecraft, and maritime ships in place of currently used foam panels and other foam products. The materials of the invention can also be used in building construction with their combination of light weight, strength, elasticity, ability to be formed into desired shapes, and superior thermal and acoustic insulation power. The materials have also been found to have utility for storage of cryogens. A cryogenic liquid or gas, such as N2 or H2, adsorbs to the surfaces in aerogel particles. Thus, another embodiment of the invention provides a storage vessel for a cryogen.

Abstract: Disclosed herein is a method for making polyimide articles that are suitable for high temperature applications. The articles disclosed herein are rigid, oxidatively stable, wear-resistant, and permeable to heated moisture and gases, and comprise co-polymer based polyimide, and at least one additive or filler, and are made using 20,000 to 50,000 psi of compression pressure.

Abstract: The invention involves composite materials containing a polymer foam and an aerogel. The composite materials have improved thermal insulation ability, good acoustic insulation, and excellent physical mechanical properties. The composite materials can be used, for instance, for heat and acoustic insulation on aircraft, spacecraft, and maritime ships in place of currently used foam panels and other foam products. The materials of the invention can also be used in building construction with their combination of light weight, strength, elasticity, ability to be formed into desired shapes, and superior thermal and acoustic insulation power. The materials have also been found to have utility for storage of cryogens. A cryogenic liquid or gas, such as N2 or H2, adsorbs to the surfaces in aerogel particles. Thus, another embodiment of the invention provides a storage vessel for a cryogen.

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: An organic aerogel or xerogel formed by a sol-gel reaction using starting materials that exhibit similar reactivity to the most commonly used resorcinol starting material. The new starting materials, including thio-, amine- and nitro-containing molecules and functionalized macrocyclic molecules will produce organic xerogels and aerogels that have improved performance in the areas of detection and sensor technology, as well as water stream remediation. Also, further functionalization of these new organic aerogels or xerogels will yield material that can be extracted with greater facility than current organic aerogels.

Abstract: A flexible polyimide foam having an apparent density of 13.5 to 900 kg/m3 and a glass transition temperature of 300° C. or higher can be prepared by mixing an aromatic tetracarboxylic acid comprising 2,3,3′,4′-biphenyltetracarboxylic dianhydride a portion of which is converted into its mono- or di-lower primary alcohol ester with an aromatic polyamine containing diaminodisiloxane in an amount of 0.1 to 10 mol. %, based on the amount of total amine compounds, to give a solid of polyimide precursor; heating the solid of polyimide precursor to a temperature of 300° C. to 500° C. to produce a polyimide foam; and compressing the polyimide foam.

Abstract: A flexible polyimide foam having an apparent density of 70 kg/m3 or less and a glass transition temperature of 300° C. or higher can be prepared by mixing an aromatic tetracarboxylic acid comprising 2,3,3′,4′-biphenyltetracarboxylic dianhydride a portion of which is converted into its mono- or di-lower primary alcohol ester with an aromatic polyamine containing diaminodisiloxane in an amount of 0.1 to 10 mol. %, based on the amount of total amine compounds, to give a solid of polyimide precursor; and heating the solid of polyimide precursor to a temperature of 300° C. to 500° C.

Abstract: A water-swellable polymer gel prepared by reacting an ester of a carboxyl group-containing polysaccharide with a compound having at least two &agr;-amino groups, which is derived from a natural amino acid, and a foamed article thereof. The water-swellable polymer gel can be used in the fields such as industry, agriculture, food and medicine. The applications of the water-swellable gel in the medical field include wound dressings, adhesion-preventing materials, dialysis membranes, hemostatic materials, adhesive materials, sealants, contact lenses, materials for tissue regeneration, microcapsule materials and drug delivery systems.

Abstract: Highly crosslinked monolithic porous polymer materials for chromatographic applications. By using solvent compositions that provide not only for polymerization of acrylate monomers in such a fashion that a porous polymer network is formed prior to phase separation but also for exchanging the polymerization solvent for a running buffer using electroosmotic flow, the need for high pressure purging is eliminated. The polymer materials have been shown to be an effective capillary electrochromatographic separations medium at lower field strengths than conventional polymer media. Further, because of their highly crosslinked nature these polymer materials are structurally stable in a wide range of organic and aqueous solvents and over a pH range of 2-12.

Abstract: A porous material made of a dry gel of a polyimide resin having an apparent density of 800 kg/m3 or less and a mean pore size of 1 &mgr;m or less is disclosed. The porous material exhibits high heat resistance and is low in density and mean pore size. The use of the porous material provided by the present invention can produce not only a heat insulator with a low thermal conductivity and high heat insulation but also an insulating material having a low dielectric constant and exhibiting excellent dielectric characteristics at high frequencies. The present invention can also provide a semiconductor circuit including the insulating material.

Abstract: Porous polyimide dielectric materials having low dielectric constants useful in electronic component manufacture are disclosed along with methods of preparing the porous polyimide dielectric materials. Also disclosed are methods of forming integrated circuits containing such porous polyimide dielectric material.

Abstract: A novel dielectric composition is provided that is useful in the manufacture of electronic devices such as integrated circuit devices and integrated circuit packaging devices. The dielectric composition is prepared by crosslinking a thermally decomposable porogen to a host polymer via a coupling agent, followed by heating to a temperature suitable to decompose the porogen. The porous materials that result have dielectric constants less than about 3.0, with some materials having dielectric constants less than about 2.5. Integrated circuit devices, integrated circuit packaging devices, and methods of manufacture are provided as well.

Abstract: A shaped article composed of an aromatic polyimide has a hollow, essentially spherical structure and a particle size of about 100 to about 1500 &mgr;m, a density of about 1 to about 6 pounds/ft3 and a volume change of 1 to about 20% by a pressure treatment of 30 psi for 10 minutes at room temperature. A syntactic foam, made of a multiplicity of the shaped articles which are bonded together by a matrix resin to form an integral composite structure, has a density of about 3 to about 30 pounds/ft3 and a compression strength of about 100 to about 1400 pounds/in2.

Abstract: The invention herein relates to a process of preparing a novel polyimide foam having superior heat-resistance, flame retardancy, homogeneous size and distribution of cells, and low density, wherein a polyimide precursor in a granular form is prepared by means of using heterocyclic amine as catalyst and then foaming. According to the present invention, the preparing process of a polyimide foam comprises reacting aromatic carboxylic acid or the anhydrides thereof with an excess of aliphatic univalent alcohol to yield an aromatic ester solution. To the aromatic ester solution, divalent amines or the mixture thereof were added in the equivalent amount of said carboxylic acid or the anhydrides thereof in addition to a catalyst and surfactant to yield a polyimide. Then, the precursor in a granular form mixture was imidized while foaming by means of pre-heating and then heating in a microwave oven, after which was cured at a high temperature.

Abstract: A mechanically undensified aromatic polyimide foam is made from an aromatic polyimide precursor solid residuum and has the following combination of properties: a density according to ASTM D-3574A of about 0.5 pounds/ft.sup.3 to about 20 pounds/ft.sup.3 ; a compression strength according to ASTM D-3574C of about 1.5 psi to about 1500 psi; and a limiting oxygen index according to ASTM D-2863 of about 35% oxygen to about 75% oxygen at atmospheric pressure. The aromatic polyimide foam has no appreciable solid inorganic contaminants which are residues of inorganic blowing agents. The aromatic polyimide which constitutes the aromatic polyimide foam has a glass transition temperature (Tg) by differential scanning calorimetry of about 235.degree. C. to about 400.degree. C.; and a thermal stability of 0 to about 1% weight loss at 204.degree. C. as determined by thermogravimetric analysis (TGA).

Abstract: A method of preparing polyimide foam produces a foam with excellent flexibility properties. The method of preparing polyimide foam is performed by foaming polyimide percursor which is prepared by employing linear aliphatic diamine and aromatic diamine containing 4 to 12 carbon atoms, at specific weight ration into the esterified reaction mixture prepared by reacting an aromatic carboxylic acid or its anhydride with excess amount of an alcohol compound. The polyimide foam produced by the method described retins superior characteristics of conventional polyimide foams and in addition have excellent flexibility so that it is used widely as adiabatic material, acoustical absorbent and cushion material in the aerospace industry, submarine and express trains etc.

Abstract: A shaped article composed of an aromatic polyimide has a hollow, essentially spherical structure and a particle size of about 100 to about 1500 .mu.m, a density of about 1 to about 6 pounds/ft.sup.3 and a volume change of 1 to about 20% by a pressure treatment of 30 psi for 10 minutes at room temperature. A syntactic foam, made of a multiplicity of the shaped articles which are bounded together by a matrix resin to form an integral composite structure, has a density of about 3 to about 30 pounds/ft.sup.3 and a compression strength of about 100 to about 1400 pounds/in.sup.2.

Abstract: An amino-acrylate polymer is prepared by the reaction of an aliphatic hydroxyl polyacrylate monomer, like pentaerythritol triacrylate, with a polyamine like a hexyldiamine to provide a rigid fast gelling and curing polymer, which polymer may be modified with resin modifiers. The amino-acrylate polymer may be used in the preparation of composite structures with fibers and filler materials.

Abstract: A polyamideamic acid resin prepolymer represented by formula A having isophorone diamine as one of monomers, ##STR1## in which k, l, m and n are integer of 1 or more, respectively, and ##EQU1## --R-- is at least one group selected from the group consisting of ##STR2## --R'-- is a cis- and trans-conformational mixture of ##STR3## high heat resistant polyamideimide foam produced therefrom, and processes for producing them are disclosed.

Abstract: A vibration-absorbing element comprised of a foamed thermoplastic polymer selected from the group consisting of polyamide elastomers, EPDM polymers and SEBS polymers containing conventional additives, the foam structure having a pore size which decreases from the inside towards the outer surface and terminating in a smooth closed surface.

Abstract: This invention relates to an article comprising a potted electrical component in a structure, wherein the electrical component is potted in a polyimide composition. The invention also relates to a method of potting electrical components comprising the steps of (1) adding a polyimide precursor to a structure including an electrical component, (2) curing the polyimide precursor to form a polyimide composition encapsulating the electrical component.

Abstract: A film forming solution which does not require aprotic polar solvents, a porous film of poly(4,4'-oxydiphenylenepyromellitimide) obtained from the film forming solution which has excellent heat and chemical resistances, which is controllable in terms of porosity and pore size of the film and which has excellent electrical characteristics, and a coated material where the porous film is formed on a base material.Particularly, a film forming solution of a precursor of poly(4,4'-oxydiphenylenepyromellitimide) and a mixture of at least three solvents which are poor solvents for the precursor when each solvent is used alone, a porous film of poly(4,4'-oxydiphenylenepyromellitimide) obtained from the film forming solution and a coated material where the porous film is formed on a base material.

Abstract: A method of and apparatus for continuously foaming a polyimide prepolymer powder which is not susceptible to heating by microwave energy utilize a preheated conveyor belt to heat the powder in contact with and adjacent the surface of the conveyor belt to commence the reaction and foaming of the powder as it enters an oven which further heats the powder by convection and infrared radiation to form a continuous foam bun. The conveyor belt is cooled as it exits the oven to cool a bottom surface of the foam product to enable the foam product to be removed from the conveyor before interior portions of the foam product have cooled. Foam adhering to the conveyor belt, after the product has been removed, is cleaned from the conveyor belt, collected and mixed with and used as a filler in the prepolymer powder used in the process. In addition the mass of the powder entering the oven and the density and degree of cure of the foam bun exiting the oven are monitored to continuously control the process.

Abstract: A polyamide precursor of a polybenzazole polymer is prepared by reacting an aromatic bis(alkenyl)ester with a ring forming, aromatic diamine. The precursor can be prepared in an organic solvent for the monomers to form a soluble polyamide precursor which can be subsequently cyclocondensed to form a PBX polymer. A polybenzoxazole precursor is prepared by the reaction of a bis(alkenyl)ester and a bis(ortho-hydroxyamine). A polybenzazole polymer is easily prepared by heating the polyamide, PBX precursor.

Abstract: A polyimide foam is prepared by heating a mixture comprising an alkyl ester of 4,4'-oxydiphthalic acid and a diamine at a temperature of 60.degree. to 350.degree. C. This foam is elastic and flame-retardant and has an excellent resistance to acid and alkali.

Abstract: Disclosed herein is a process for preparing a reaction product containing methylene diphenylamine comprising reacting aniline with an aldehyde, in the presence of a low level of an acid wherein the acid level is reduced before digesting reaction mixture at a high temperature which is sufficient to effect a rearrangement of the intermediates to produce a reaction product containing methylene diphenylamines and low levels of impurities.

Abstract: Polyimide foam of desired density is produced by adding to a polyimide precursor comprising carboxylic and diamine components at least one foam-enhancing polar, protic additive of the formula ROH, where R is hydrogen, or C.sub.1 to C.sub.12 linear or branched alkyl or cycloalkyl, unsubstituted or substituted with halo, aryl, alkoxy or hydroxy, and heating the resultant slurry to a temperature that does not exceed about 105.degree. C. to form a homogeneous melt. When heated to a higher temperature the melt foams and cures. The density of the foam is affected by the amount of foam-enhancing additive which is utilized.

Abstract: The invention is directed to an unfoamed foil of at least one thermoplastic resin, said foil being capable of serving as an adhesive when softened and having included therein at least one blowing agent, and to the use thereof in preparing laminates.