Abstract: A method for sulfonating items comprising polybenzazole polymers is described. These sulfonated polybenzazole items are incorporated into composites containing a matrix resin such as an epoxy resin. The interfacial shear strength of these sulfonated polybenzazole fiber-containing composites is significantly improved over the interfacial shear strength of similar composites containing unsulfonated polybenzazole fibers.
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;T=methallyl or allyl;Me=methyl;R.sub.2 =a trivalent organic radical; andR.sub.3 =a divalent organic radical.The amideimide 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: A polyamide comprising a recurring unit of the formula (I), ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 is independently a hydrogen atom, a halogen atom, a hydroxyl group, or a group of a carbon skeleton which may contain a hetero atom or a halogen atom, and A.sup.1 is a divalent hydrocarbon group; and a process for the production of a polyamide comprising the recurring unit of the formula (I), which comprises subjecting to a polycondensation reaction a dicarboxylic acid comprising an alicyclic dicarboxylic acid of the formula (a)-1, ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are as defined in the formula (I), and a diamine of the formula (b)-1,H.sub.2 N-A.sup.1 -NH.sub.2 (b)-1wherein A.sup.1 is as defined in the formula (I).
Abstract: Linear aromatic polyimides containing the cyclobutene-3,4-dione moiety were produced by reacting 1,2-bis(4-aminoanilino)cyclobutene-3,4-dione with several aromatic dianhydrides. The resulting polymers exhibited glass transition temperatures greater than 500.degree. C., adhered tenaciously to glass, and became more flexible after heating for 1 hour at 300.degree. C.
Type:
Grant
Filed:
March 3, 1992
Date of Patent:
May 18, 1993
Assignee:
The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
Abstract: The semicrystalline polyimide prepared by reaction of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and 1,3-bis(4-aminophenoxy-4'-benzoyl)benzene (1,3-BABB) is modified so that it can be more readily processed to form adhesive bonds, moldings and composites. The stoichiometric ratio of the two monomers, BTDA and 1,3-BABB is controlled so that the intermediate polyamide acid is of a calculated molecular weight. A polyamide acid with excess anhydride groups is then reacted with the stoichiometrically required amount of monofunctional aromatic or aliphatic amine required for complete endcapping. A polyamide acid with excess amino groups is reacted with the stoichiometrically required amount of monofunctional aromatic anhydride required for complete endcapping. The stoichiometrically offset, endcapped polyimide is processed at lower temperatures and pressures than the unmodified high molecular weight polyimide with the same repeat unit, and exhibits an improved melt stability.
Type:
Grant
Filed:
May 8, 1990
Date of Patent:
May 18, 1993
Assignee:
The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
Inventors:
Paul M. Hergenrother, Stephen J. Havens, Mark W. Beltz
Abstract: AB-polybenzoxazole monomer, such as 3-amino-4-hydroxybenzoic acid, can be synthesized in high yields from a hydroxy-benzoic acid or related compound in a three-step process of (1) nitration, (2) hydrolysis of the ester, and (3) reduction of the nitro moiety. The monomer is conveniently recovered as a phosphate salt in high purity by precipitating and recrystallizing from a phosphoric acid solution. The monomer may be polymerized in high concentrations in polyphosphoric acid containing high levels of P.sub.2 O.sub.5 to yield a high molecular weight polymer without dehydrohalogenation.
Type:
Grant
Filed:
June 29, 1990
Date of Patent:
May 11, 1993
Assignee:
The Dow Chemical Company
Inventors:
William J. Harris, Zenon Lysenko, Carl W. Hurtig
Abstract: In a process for the preparation of polyimide by reacting a diamine compound with tetracarboxylic dianhydride in a phenol based solvent, an improved process for reacting the diamine compound with tetracarboxylic dianhydride in a solution by forming separate solutions of the tetracarboxylic dianhydride and the diamine compound and mixing the solutions and/or by dissolving tetracarboxylic dianhydride in the phenol-based solvent containing an organic base.
Abstract: Phosphazene-containing amines having at least one amine or substituted amine moiety reactive with nitrile groups of the phthalonitrile monomers or oligomeric resins are useful curing agents for phthalonitriles. Typically, the phosphazene-containing amines useful as curing agents in the present invention have the formula: ##STR1## wherein each of X.sub.1-6 is a hydrogen, an unsubstituted amine group, or an amine group substituted with C.sub.1 -C.sub.12 alkyl groups or aromatic groups, at least one of X.sub.1-6 includes an amine group, and each of R'.sub.1-6 is an alkyl, aromatic, or alkyl-substituted aromatic moiety, or a linear polymer of the phosphazene-based amine monomer. The curing agents enhance the speed of cure and also add flame retardancy to the cured polymers.
Abstract: Integrated circuit sockets for use in a burn-in test are disclosed. The IC sockets are produced by injection molding of a specific polyimide having an inherent viscosity of 0.35 to 0.65 dl/g and essentially consisting of recurring units represented by the formula (I): ##STR1## wherein X is a radical selected from the group consisting of a bond, divalent hydrocarbon having from 1 to 10 carbon atoms, etc. and R is a tetravalent radical selected from the group consisting of an aliphatic radical having two or more carbon atoms, cycloaliphatic radical, monoaromatic radical etc.
Abstract: Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): ##STR1## wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5% or more, and fed to an extruder to obtain articles.
Abstract: A melt processable poly(ester-amide) which is capable of forming an anisotropic melt phase is provided. A poly(ester-amide) of the present invention may have recurring units of: (a) 4-hydroxybenzoyl moiety, (b) 6-oxy-2-naphthoyl moiety, (c) 4,4'-biphenol moiety, (d) terephthaloyl moiety, and (e) an aromatic moiety capable of forming an amide linkage in the proportions indicated. Preferably, the moiety capable of forming an amide linkage is derived from p-aminophenol, p-phenylenediamine, N-acetyl-p-aminophenol, etc. The resulting poly(ester-amide) is capable of undergoing melt-processing in the temperature range of from about 300.degree. to about 400.degree. C.
Abstract: A tri-component polyimide copolymer and the process of preparing the copolymer are disclosed. A mixed reaction medium or solvent system comprising phenol and at least one compound of resorcinol, 1,6-dimethyl phenol and 4-methoxy phenol is used to produce the copolymer by direct imidization without isolating or purifying the imide oligomer as an intermediate.
Abstract: Rigid-rod aromatic heterocyclic polymers having repeating units of the formula: ##STR1## wherein Ba is a benzobisazole moiety of the formula: ##STR2## wherein X is --O--, --S-- or --NH.
Type:
Grant
Filed:
May 22, 1992
Date of Patent:
April 6, 1993
Assignee:
The United States of America as represented by the Secretary of the Air Force
Abstract: Disclosed is a liquid developer comprising a liquid medium, a charge control agent, a polymeric surfactant, and a colored core polymer. In one embodiment, the colored polymer is of the formula ##STR1## wherein A is selected from the group consisting of alkylene and arylene, B is selected from the group consisting of ##STR2## wherein R is selected from the group consisting of alkylene groups, arylene groups, and polyether groups, D is selected from the group consisting of dioxyalkane and dioxyarene, x is a fraction number of from about 0.01 to 1.0, and y is a fraction number of from 0 to about 0.99, with x+y being equal to 1, and n representing the number of the monomer units.
Type:
Grant
Filed:
October 1, 1990
Date of Patent:
April 6, 1993
Assignee:
Xerox Corporation
Inventors:
Beng S. Ong, Melvin D. Croucher, Raymond W. Wong
Abstract: Linear or multidimensional, crosslinking, solvent resistant oxazole, thiazole, or imidazole (i.e., heterocycle) oligomers and blends of the crosslinking oligomers and noncrosslinking comparable polymers are described. The oligomers are prepared by reacting tetraamines, diaminodiols, or diaminothiols (i.e. four-functional compounds) with poly-carboxylic acid halides, and crosslinking phenylimide end cap monomers in a suitable solvent under an inert atmosphere.
Abstract: A thermoplastically processable aromatic polyamide is prepared by polycondensing diacid monomer A with diamine monomer B: (A) HOOC--Ar--COOH;(B) H.sub.2 N--Ar'--NH.sub.2 ; wherein Ar is 1,3-- or 1,4-phenylene; 1,4--, 1,5--, 2,6-- or 2,7-naphthylene, ##STR1## and Ar' is ##STR2## wherein X is --SO.sub.2 -- or --CO--; Y is --O-- or --S--; Z is --O--, --S--, --SO.sub.2 --, --CO-- or ##STR3## wherein R and R' each is --H or C.sub.1 -- to C.sub.4 -alkyl and n is 0 or 1 in the melt at a temperature in the range of from 200.degree. to 400.degree. C. in the presence of a catalyst selected from the group consisting of alkyl- or aryl-phosphonic acids, -phosphonous acids, -phosphinic acids, esters thereof, halides thereof and mixtures thereof, the catalyst content being 0.01 to 2.0 mol % relative to the total content of components A and B.
Abstract: Preparation of specially substituted aromatic polyamides containing structural units of the formula I mentioned and copolyamides containing at least 10 mol % of structural units of the formula I and structural units of the formula II mentioned and their use as orientation layer in liquid crystal display elements and/or liquid crystal switching elements.
Type:
Grant
Filed:
December 17, 1991
Date of Patent:
March 23, 1993
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Hans-Rolf Dubal, Mikio Murakami, Otto Herrmann-Schonherr, Arnold Schneller
Abstract: A polyimide having a high heat-resistance good processability and recurring structural units of the formula (I): ##STR1## wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having at least two carbon atoms, alicyclic radical, monocyclic aromatic radical, fused polycyclic aromatic radical and polycyclic aromatic radical bonded through a direct bond or a bridge member.
Abstract: Azole rings, such as oxazole and thiazole rings, can activate an aromatic ring bonded to a leaving group such as a halogen atom so that the aromatic ring will undergo aromatic nucleophilic substitution. The reaction is useful for making ethers, thioethers and amines containing azole rings. In particular, monomers having azole rings, activated aromatic rings with leaving groups and nucleophilic moieties can react under conditions of aromatic nucleophilic displacement to form non-rigid rob PBZ polymers. The non-rigid rod PBZ polymers can be used to form molecular composites with rigid rod PBZ polymers which molecular composites are not substantially phase separated.
Type:
Grant
Filed:
January 10, 1992
Date of Patent:
March 16, 1993
Assignee:
The Dow Chemical Company
Inventors:
Muthiah N. Inbasekaran, Michael J. Mullins
Abstract: Crystallizable polyphthalamides with a useful combination of thermal and mechanical properties comprising recurring moieties of terephthalic acid, adipic acid, an aliphatic diamine of 4 to 20 carbon atoms and meta-xylylene diamine.
Abstract: Aromatic polyamides with an improved stability toward thermal oxidation was achieved by polycondensation being performed in the presence of 0.05 to 4 mol % of a catalyst comprising a mixture of phosphorus compounds and metal salts.With the process according to the invention, it is possible to obtain aromatic polyamides stable toward thermal oxidation.
Abstract: It is advantageous to prepare oligomers of polybenzazole polymers by reaction of AA-PBZ monomer with an excess of BB-PBZ monomer. The resulting oligomer dopes may be stored at a temperature at which they remain pumpable until such time as the dope can be advanced to higher molecular weight by adding additional AA-PBZ monomer. The molecular weight of the polymer may be adjusted by controlling the amount of chain extender and/or chain terminator added to oligomer mixtures as they are advanced to final molecular weight.
Type:
Grant
Filed:
October 19, 1990
Date of Patent:
March 16, 1993
Assignee:
The Dow Chemical Company
Inventors:
Thomas Gregory, Carl W. Hurtig, Harvey D. Ledbetter, Kenneth J. Quackenbush, Steven Rosenberg, Ying H. So
Abstract: Rigid fluorine-containing compounds, monomers, and polymers based on pentacyclic core systems, such as 12H,14H-5, 7-dioxapentacene with perfluoroalkyl and/or aryl groups in the 12, 14 positions, and 5H,12H-7, 14-dioxapentacene, with perfluoroalkyl and/or aryl groups in the 5,12 positions. These monomers have utility in the preparation of advanced high-performance polymers, particularly polyimides. The rigid pentacyclic core decreases the coefficient of thermal expansion of the polymers, while the fluorinated substituents improve the dielectric constant and water absorption properties. Each monomer unit contains within its pentacyclic core two-O-bridges, and two --CRR.sub.f bridges (where R is aryl, substituted aryl or perfluoroalkyl, and R.sub.f is perfluoroalkyl).
Abstract: An aromatic polyesteramide possessing thermotropic liquid crystalline polymer characteristics, which are easily workable in the molten state and have the mesogenic group in the main chain, are obtained by condensing possible substituted aminophenols and hydroquinone derivatives with aromatic dicarboxylic acids.
Type:
Grant
Filed:
December 3, 1990
Date of Patent:
February 9, 1993
Assignee:
Himont Italia S.r.l.
Inventors:
Francesco Casagrande, Marco Foa', Larry L. Chapoy
Abstract: Perfluoroalkylated diaminoesitylene and polymers, preferably polyimides, made therefrom. The necessarily obtainable meta-substitution position of the perfluoroalkyl group with respect to both amino-groups provides an improved diamine and compositions of matter resulting therefrom.
Type:
Grant
Filed:
April 4, 1991
Date of Patent:
January 5, 1993
Assignee:
E. I. Du Pont de Nemours and Company
Inventors:
Brian C. Auman, David P. Higley, Bruce B. Johnson
Abstract: A wholly aromatic copolymer and a shaped article thereof having an excellent mechanical property, high resistances to heat and chemicals, and a satisfactory processability, is composed of (1) an aromatic dicarbonyl moiety consisting of recurring dicarbonyl units (A) and (B): ##STR1## and (2) an aromatic diamine moiety consisting of recurring diamine units (C) and (D): ##STR2## and the recurring dicarbonyl units (B) being in an amount of 0.01 molar % or more but less than 20 molar % based on the total molar amount of the dicarbonyl moiety (1), and the recurring diamine units (D) being in an amount of 60 molar % or less but more than 20 molar % based on the total molar amount of the diamine moiety (2).
Abstract: Polyimide intercondensation products are prepared from mixed dianhydrides and aromatic diamines. One of the mixed dianhydrides must be 2,2-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride (6FDA) and the other dianhydride may be oxydiphthalic anhydride (ODPA) or biphenyl dianhydride (BPDA) or mixtures thereof. Preferred aromatic diamines are p-phenylenediamine (PPD) and/or m-phenylenediamine (MPD). The polyimide products have increased glass transition temperatures (Tg), frequently higher than 400.degree. C. Composites made from the polyimides have high thermal and oxidative stability and may be used in aircraft engine hardware.
Abstract: Polyimide compositions, films, and electronic devices using polyimides, based on 9-aryl-9(perfluoroalkyl)-xanthene-2,3,6,7-dianhydride and one or more diamines from a selected group, which offers to the polyimides a combination of desirable properties including solubility, pseudo rod-like structure, low linear coefficient of thermal expansion, high glass transition temperature, low dielectric constant, and high modulus.
Abstract: A new class of soluble phenylated polyimides made from 3,6-diarypyromellitic dianhydride and process for the manufacture of the 3,6-diarypyromellitic dianhydride starting material. The polyimides obtained with said dianhydride are readily soluble in appropriate organic solvents and are distinguished by excellent thermal, electrical and/or mechanical properties making the polyimides ideally suited as coating materials for microelectronic apparatii, as membranes for selective molecular separation or permeation or selective gas separation or permeation, or as reinforcing fibers in molecular composites, or as high modulus, high tensile strength fibers.
Abstract: Aromatic homopolyimide and copolyimide films derived from an aromatic dianhydride and a chlorinated aromatic diamine such as 2-chloro-p-phenylene diamine and 2,2'-dichloro-4,4'-diaminodiphenyl ether are described. The films have low water absorption, high elastic modulus and elongation and can be heat-processed without embrittlement.
Abstract: Polyimide resins, which have reduced anhydride content when molded, are prepared by a novel reaction process that includes reacting an esterified aromatic tetracarboxylic acid or anhydride monomer with a primary aromatic diamine until substantially no free monomer remains to form a polyamide-acid (the molar ratio of esterified monomer to diamine ranging from 1:1 to 1:2); reacting the polyamide-acid with a low molecular weight end-capping agent to form an end-capped polyamide-acid; and heating the end-capped polyamide-acid to form the polyimide.
Abstract: Rigid-rod aromatic heterocyclic copolymers having repeating units of the formula: ##STR1## wherein n has a value of about 0.10 to 0.99, m is 1.0-n, Ar is a para-ordered divalent aromatic moiety, as defined hereinafter, and wherein Ba is a benzobisazole moiety of the formula: ##STR2## wherein X is --O--, --S-- or --NH. Ar can be any para-ordered divalent moiety such as, for example, 1,4-phenylene, 4,4'-biphenylene, 4,4"-terphenylene, and the like, as well as substituted divalent moieties, such as, for example: ##STR3## wherein R is Q or an alkyl group having 1 to 4 carbon atoms, wherein Q is ##STR4## wherein Z is --O-- or --S--; ##STR5## wherein R is as defined above, or ##STR6## wherein R.sup.1 and R.sup.3 are --H or -phenyl, R.sup.2 is --H or ##STR7## wherein Q is as defined above, and R.sup.4 is R.sup.
Type:
Grant
Filed:
May 22, 1992
Date of Patent:
December 29, 1992
Assignee:
The United States of America as represented by the Secretary of the Air Force
Abstract: The present invention relates to a novel class of aromatic diamine monomers, benzoxazole polymers made from said class of monomers, and polymer-matrix composites which may be produced therefrom. The present invention also relates to methods of producing said polymers and said polymer-matrix composites. The polymer-matrix composites have as one advantage high strength and temperature resistance.
Abstract: An improved low toxicity polymerization of monomer reactants (PMR) system has 3,4'-oxydianiline as the key monomer reactant. One variation of this system, LaRC-RP46, is prepared by reacting together monomethyl ester or 5-norbornene-2,3-dicarboxylic acid (NE), 3,4'-oxydianiline (3,4'-ODA), and dimethyl ester of 3,3',4,4'-benzophenonetetracarboxylic acid (BTDE); this combination is then treated with heat. This new matrix resin is readily processed into a high quality graphite fiber reinforced composite with excellent reproducibility. The flexibility of the ether linkage in 3,4'-ODA provides high toughness. The composite retains excellent mechanical properties both at 316.degree. C. and at 371.degree. C. The development of LaRC-RP46 will significantly extend the applications of PMR type polyimides.
Type:
Grant
Filed:
February 5, 1991
Date of Patent:
December 15, 1992
Assignee:
The United States of America as represented by the Administrator of National Aeronautics and Space Administration
Abstract: Disclosed is an aromatic copolyimide film prepared by chemical conversion of a copolyamide acid solution obtained by copolymerization of an aromatic tetracarboxylic acid component comprising from 30 to 50 mole % of biphenyltetracarboxylic acid dianhydride, 50 to 70 mole % of pyromellitic acid dianhydride, 60 to 80 mole % of p-phenylenediamine and 20 to 40 mole % of 4,4'-diaminodiphenyl ether. The aromatic copolyimide film has a low coefficient of thermal expansion, low water absorption, a low coefficient of hygroscopic expansion, high mechanical strength and is readily etchable making it suitable for use an advanced electronic substrate.
Abstract: The present invention comprises diamantane groups interspersed among benzothiazole groups, benzoxazole groups or benzimidazole groups. This constitutes a rigid-rod polymer with stable cycloaliphatic groups interspersed into the aromatic-heteroaromatic backbone of the rods. The presence of the aliphatic groups decreases crystallinity by adding disorder to the rods thus minimizing interactions between the heteroaromatic groups. The interspersed aliphatic groups act as insulators and thus permit greater relative protonation. Also, the reduced conjugation of the aromatic-heteroaromatic rings reduces the color of the polymers. The preferred method of manufacturing this improved rigid-rod polymer is by condensation of dimethyl diamantanecarboxylate with 2,5-diamino-1,4-benzenedithiol, 1,2,4,5-tetraaminobenzene, or 4,6-diamino-1,3-benzenediol.
Type:
Grant
Filed:
April 29, 1991
Date of Patent:
November 24, 1992
Assignee:
Fluorochem, Inc.
Inventors:
Thomas G. Archibald, Aslam A. Malik, Kurt Baum
Abstract: Polyamides of the general formula [N(A)-X-N(B)-CO-Y-CO-].sub.n are described, in which Y denotes a divalent group, X a divalent radical whose chain contains at least two carbon atoms, A and B independently of one another denote H or a C.sub.1 to C.sub.26 alkyl group and n denotes an integer greater than 4. The said polyamides contain at least one alkyl group of C.sub.6 to C.sub.26 per repeating unit. The groups X and/or Y contain at leat one CH.sub.2 group in the chain. The polyamides are prepared by reaction of a diamine of the formula NHA-X-NHB with an about equimolar amount of a reactive derivative of a dicarboxylic acid of the formula COOH-Y-COOH. The polyamides obtained can be used in order to prepare highly ordered monomolecular LB films on a support. For this purpose, the polyamide is dissolved in a volatile organic solvent which is immiscible with water and the solution is spread on the water/air interface.
Type:
Grant
Filed:
September 5, 1989
Date of Patent:
November 24, 1992
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Harald Cherdron, Werner Prass, Ude Scheunemann, Donald Lupo
Abstract: Soluble and/or fusible polyimides or polyamidoimides of the general formula I ##STR1## in which R denotes a divalent radical of the formula II ##STR2## Ar denotes trivalent or tetravalent aromatic radicals or mixtures thereof, X denotes the amide radical, if Ar is trivalent, and if Ar is tetravalent denotes the imide radical and R.sub.1 denotes divalent aromatic radicals, and a process for their preparation.
Type:
Grant
Filed:
June 12, 1990
Date of Patent:
November 17, 1992
Assignee:
Chemie Linz Gesellschaft m.b.H.
Inventors:
Gerd Greber, Heinrich Gruber, Marcel Sychra
Abstract: The invention provides aromatic polyamides having an improved resistance to thermo-oxidation. This is achieved by carrying out the polycondensation in the presence of a catalyst system which comprises a mixture of a phosphorus compound and a tin(II) compound or is a compound which contains both elements. The process according to the invention allows aromatic polyamides to be obtained which are resistant to thermo-oxidation (discoloration).
Type:
Grant
Filed:
October 24, 1990
Date of Patent:
November 10, 1992
Assignee:
Huels Aktiengesellschaft
Inventors:
Gunter Poll, Martin Bartmann, Jurgen Finke
Abstract: Novel thermotropic semialiphatic copolyesteramides having relatively low melt temperatures contain the following recurring structural units: ##STR1## in which Ar.sub.1 is a divalent aromatic and/or cycloaliphatic radical, Ar.sub.2 is a divalent aromatic radical, X is --NH-- or --CO--, and A includes a divalent aliphatic hydrocarbyl radical.
Abstract: Polyimide prepared from 3,3'4,4'-biphenyltetracarboxylic dianhydride and an aromatic diamine which is at least about 60% meta-phenylene diamine exhibits excellent hydrolytic and oxidative stability.
Abstract: A polymeric acid is synthesized by the ring-opening poly-addition reaction using a biphenyl tetracarboxylic acid as a tetracarboxylic acid moiety and an aromatic diamine, particularly p-phenylene diamine, as a diamine moiety. An aromatic polyimide resin layer possessing a highly desirable heat-resisting property as a heat-resistant insulating coating material and excelling in adhesive strength relative to a substrate is obtained by adjusting the polymeric acid in viscosity with a suitable organic solvent, applying the resultant polyamic acid on a substrate, and firing the applied layer of the polyamic acid. The substrate, for example, is a conductor layer formed as with copper and used as a multi-layer wiring board for hybrid IC's.
Type:
Grant
Filed:
August 29, 1989
Date of Patent:
October 20, 1992
Assignees:
Kabushiki Kaisha Toshiba, Toshiba Chemical Corporation
Abstract: The thermooxidative stability and thermomechanical properties of advanced composites which use high performance resin matrices such as polyimides and high strength carbon fibers may be improved by sizing the carbon fibers with uncapped or capped linear polyamideimides.The uncapped linear polyamideimides useful as carbon fiber sizings generally contain repeating units having the general formula: ##STR1## wherein R.sub.2 =a trivalent organic radical and generally benzenetriyl;R.sub.3 =a divalent organic radical; andn=an integer sufficiently large to provide a strong, tough coating.Useful capped, linear polyamideimide oligomers may be formed by including end caps with an unsaturated functionality (Y) containing a residue selected from the group consisting of: ##STR2## wherein R.sub.1 =lower alkyl, lower alkoxy, aryl, aryloxy, substituted alkyl, substituted aryl, halogen, or mixtures thereof;j=0, 1, or 2;i=1 or 2;G=--CH.sub.2 --, --O--, --S--, --SO.sub.2 --, --SO--, --CO--, --CHR--, or --CR.sub.
Type:
Grant
Filed:
April 28, 1989
Date of Patent:
October 13, 1992
Assignee:
The Boeing Company
Inventors:
Hyman R. Lubowitz, Clyde H. Sheppard, Ronald R. Stephenson
Abstract: Polybenzoxazole polymers can be synthesized from BB-monomer having pendant methyl groups. The resulting polymer has pendant methyl groups, which can be used to cross-link the polymers.
Abstract: A novel liquid crystal polymer comprising repeating units having the structure (I): ##STR1## and a method for preparing such liquid crystal polymer are described.
Abstract: Block copolymers can be formed from heterocyclic polymers such as PBO and thermoplastic polymers such as polyamide or poly(aromatic ether ketone). The block copolymer compositions are thermoplastic and do not experiSTATEMENT OF GOVERNMENT INTERESTThis invention was made with Government support under contract F33615-86-C-5068 awarded by the Department of the Air Force. The Government has certain rights in this invention.
Abstract: There is described a process for preparing aromatic polyamides of high hydrolysis resistance by reacting aromatic diamines in a conventional organic solvent and in the presence or absence of inorganic salts wherein the diamine, which has a water content of up to 25% by weight, is dissolved in the organic solvent, which may likewise contain water, and the solution is subjected to a vacuum distillation until the water content of the bottom product is <100 ppm and subsequently the inorganic salts if necessary and then the dicarbonyl dichloride are added in a conventional manner and the condensation reaction is performed and concluded in a conventional manner.
Type:
Grant
Filed:
April 3, 1991
Date of Patent:
September 22, 1992
Assignee:
Hoechst Aktiengesellschaft
Inventors:
Georg-Emrich Miess, Peter Klein, Wilfried Pressler