Abstract: A macroscopically isotropic side chain liquid crystal polymer is described containing photochromic mesogenic groups and which through irradiation with light is capable of being permanently or substantially permanently converted into an optically anisotropic phase without having been pre-oriented. The polymer is preferably a polyester between on the one hand either an aliphatic, optionally substituted, .alpha.,.omega.-dicarboxylic acid having a total chain length of up to 24 carbon atoms, or an aryl-, in particular phenyl-, carboxylic acid, and on the other hand an optionally substituted 1,3-propanediol containing the mesogenic group, or a group containing the mesogenic group, attached to the carbon in the 2-position. Furthermore, an optical storage device comprising a film of the polymer.

Abstract: The present invention provides novel substituted biphenyl pyrazines or pyrazine derivatives ("BPD") which are functional and have useful application as a monomer for a variety of high performance polymers such as polyester, polyarylate, polycarbonate, polyetherketones, epoxides, polyimides, polyamides, and polyamides-imides; and as pigments for coating compositions such as paints. These BPD have the general formula: ##STR1## wherein R.sub.1 -R.sub.8 and n are defined herein.

Abstract: Oligomeric monomers are produced by reaction of a bisphenol compound with ther a dihalobenzophenone or a (2,2)bis(4-halophenyl)hexafluoropropane and any other activated halogen containing aromatic compounds in the presence of a base and an appropriate solvent. The resulting oligomeric product, a dialkaline bisphenate terminated salt, is then reacted with 4-nitrophthalonitrile to form an oligomer-based phthalonitrile. These oligomers, in the presence or absence of an curing agent, may then be heated to form high temperature thermosetting polymers. These polymers can potentially be used as advanced materials for composites, as adhesives, and for microelectronic applications.

Abstract: A method of providing electronic shielding comprising providing a layer of a polyaniline composition on the object to be shielded, whereby the entrance and egress of electromagnetic radiation is prevented. Also presented herein is a method of changing the absorption by a polyaniline composition of electromagnetic radiation by modifying the chemical structure and crystallinographic order of the polyaniline composition, wherein said composition comprises a composition of the formula ##STR1## where y can be equal to or greater than zero, and R.sup.1 and R.sup.2 are independently selected from the group consisting of --H, --OCH.sub.3, --F, --Cl, --Br, --I, --NR.sup.3.sub.2, --NHCOR.sup.3, --OH, --O, --SR.sup.3, --OR.sup.3, --OCOR.sup.3, --NO.sub.2, --COOH, --COOR.sup.3, --R.sup.3 SO.sub.3 H, --COR.sup.3, --CHO, and --CN, where R.sup.3 is a C.sub.1 to C.sub.8 alkyl, aryl, or aralkyl group.

Abstract: A method for preparing a polyaniline having a desired molar mass. Control of the molar mass of the polyaniline is achieved in connection with an aniline polymerization reaction, by feeding aniline and an oxidizing agent participating in the polymerization reaction gradually into a polymerization vessel. By varying the feeding speeds of the aniline and the oxidizing agent, polyanilines having different molar masses are obtained.

Abstract: Described are compositions protected against thermal and oxidative degradation that compriseA) a polyether polyol or mixtures of such polyols,B) at least one benzofuranone derivative of formula I, ##STR1## wherein L, G, m, R.sub.1 to R.sub.5 and R.sub.21 to R.sub.24 are as defined in claim 1,C) at least one compound from the group of the phenolic anti-oxidants, and/orD) at least one compound from the group of the amino anti-oxidants of the secondary amine type. Also polyurethane(s) (foam(s)) prepared therefrom are protected against thermal and oxidative degradation, especially against core scorching.

Abstract: Described herein is a process for synthesizing polybenzazole polymers comprising: (a) contacting a bis(trihalomethyl) organic compound with a polyphosphoric acid under reaction conditions sufficient to convert at least about 25 mole percent of the trihalomethyl groups present to carboxylic acid or carboxylate groups, forming a reaction mixture thereby; and (b) contacting the reaction mixture with an aromatic compound having two o-amino-basic moieties under reaction conditions sufficient to form a polybenzazole polymer.

Abstract: This invention relates to a process for the enzymatic synthesis of electrically conductive substituted and unsubstituted polyanilines. Aniline monomer(s), an oxidizing agent, which comprises an enzyme and an electron acceptor, and an acidifying agent are reacted together to form polyanilines.

Abstract: Novel molecular weight controlled and endcapped polybenzimidazoles (PBI) are prepared by the aromatic nucleophilic displacement reaction of di(hydroxyphenylbenzimidazole) monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The PBI are endcapped with mono(hydroxyphenyl)benzimidazoles. The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. Mono(hydroxyphenyl)benzimidazoles are synthesized by reacting phenyl-4-hydroxybenzoate with aromatic (o-diamine)s in diphenylsulfone. Molecular weight controlled and endcapped PBI of new chemical structures are prepared that exhibit a favorable combination of physical and mechanical properties.

Abstract: Micromachined organic crystals are used in electro-optic modulators to provide high speed modulation capability. Machined modulator blocks of organic crystal material, such as dimethylamino n-methylstilbazolium tosylate (DAST), have smooth surfaces adapted to couple light between the organic crystal and a medium adjoining the crystal in the electro-optic modulator. Electrodes are disposed with respect to the modulator block such that an electric field is generated along a selected axis corresponding to the polar axis of the organic crystal. A method of machining the soft organic crystal adapted for use as a modulator includes illuminating the organic crystal material via an opaque mask having a selected pattern corresponding to a desired machined pattern for the organic crystal.

Abstract: Epoxy resins containing more than one vicinal epoxide group per molecule and at least one thiadiazole, oxadiazole or both thiadiazole and oxadiazole moiety per molecule are disclosed, as well as curable and cured compositions thereof. Certain of these epoxy resins possess enantiotropic liquid crystallinity. These enantiotropic epoxy resins are useful in preparing copolymers with high glass transition temperatures and liquid crystalline morphology, which can result in enhanced unidirectional mechanical properties. These epoxy resins are useful in coating, casting, encapsulation, electronic or structural laminate or composite, filament winding or molding applications.

Abstract: Disclosed is a novel composition of matter comprising a polyacid and a polymer containing repeating units which contain one or more basic atoms. The complex is water-soluble and electrically conductive. The complex is useful in providing organic discharge layers for use in electronic applications and fabrications.

Abstract: Oligomeric monomers are produced by reaction of a bisphenol compound with ther a dihalobenzophenone or a (2, 2) bis (4-halophenyl) hexafluoropropane and any other activated halogen containing aromatic compounds in the presence of a base and an appropriate solvent. The resulting oligomeric product, a dialkaline bisphenate terminated salt, is then reacted with 4-nitrophthalonitrile to form an oligomer-based phthalonitrile. These oligomers, in the presence or absence of an curing agent, may then be heated to form high temperature thermosetting polymers. These polymers can potentially be used as advanced materials for composites, as adhesives, and for microelectronic applications.

Abstract: An electrically conducting plastic material is produced by blending a polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof. A reaction product or blend of a polyaniline or a derivative thereof with an organic sulfonic acid or a derivative thereof can be brought to an easy-to-handle or directly melt-processable form through a heat-treatment process carried out at approx. +40.degree. to +250.degree. C. The obtained plastic material is advantageously further improved by blending the heat-treated reaction product or blend with a thermoplastic polymer and then melt-processing the mixed blend. The properties of the resulting compound material exhibit complete compatibility of the heat-treated reaction product or blend with the thermoplastic polymer.

Abstract: Compositions and methods are described that relate to the use of reaction products of metal compounds and protonic acids for plasticizing and neutralizing acidic, protonated compositions comprising substituted and unsubstituted polyanilines and co-polymers and or mixtures thereof; and for reducing the percolation threshold for conductivity in blends with insulating bulk polymers.

Abstract: A process for the in vitro production of chemically modified polyphenolic polymer (PPP). First, stable, highly active extracellular tyrosinase is produced from genetically transformed microorganism such as Streptomyces antibioticus. The tyrosinase is then incubated with a reaction substrate such as l-tyrosine, hydrolyzed protein, or an oligopeptide in combination with l-tyrosine. The ratio of the oligopeptide/tyrosine combination as well as variation in the concentration of tyrosinase can be used to modify the color, the molecular size, and the spectral absorbance properties of the PPP produced. Alternatively, or additionally, oxidants such as hydrogen peroxide or hypochlorite can be used to modify the color of the PPP, regardless of the method used to produce the PPP, and the PPP can subsequently be fractionated using molecular weight cut-off ultrafiltration. Organic solvents can also be used in the method of making PPP to produce PPPs having variable but reproducible physical properties.

Abstract: Novel cyclic imino ether compositions containing one or more mesogenic moieties, when polymerized, result in products having improved properties.

Abstract: In reactions to form PBZ polymers such as polybenzoxazole, monomers having an aromatic group bonded to a primary amine group and to a hydroxy, thio or amine group ortho to said primary amine group are contacted with monomers having an electron-deficient carbon group. In the present invention the electron deficient carbon group may be an alkali metal carboxylate group or a trihalomethyl group. Useful monomers include, for example, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexachloroxylene and disodium terephthalate.

Abstract: A method of emulsion polymerization of aniline or substituted anilines for making substituted or unsubstituted homopolymers and co-polymers of aniline. The method includes formation of an emulsion of aniline monomers, polar solvent, non-polar or weakly polar solvent and functionalized protonic acid, which is selected for its ability to perform two functions: acting as a surfactant and acting as a protonating agent (dopant) in producing an electrically conducting polymer. Then, an oxidant is added to polymerize the ingredients of the emulsion. This method provides polyaniline particles of highly crystalline and oriented morphologies of controlled aspect ratios.

Abstract: The invention provides for a process of using a static dissipative, polymeric composition to prevent electrostatic discharge. The static dissipative, polymeric composition is both humidity independent and water insoluble. The present invention also provides an article comprising a substrate to be protected from electrostatic discharge.

Abstract: Di(hydroxyphenyl)benzimidazole monomers were prepared from phenyl-4-hydroxybenzoate and aromatic bis(o-diamine)s. These monomers were used in the synthesis of soluble polybenzimidazoles. The reaction involved the aromatic nucleophilic displacement of various di(hydroxyphenyl)benzimidazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds in the presence of an alkali metal base. These polymers exhibited lower glass transition temperatures, improved solubility, and better compression moldability over their commercial counterparts.

Abstract: Electroactive polymers are provided which contain alternating phenyl rings and nitrogen atoms, and which contain both quinoid mer units and benzenoid mer units. The polymers are formed by poly(condensation) of N-phenylhydroxylamine or derivatives thereof under anhydrous conditions in the presence of a Lewis acid catalyst. Methods for producing films, fibers and shaped articles of the polymers are provided as well.

Abstract: A process for preparing a polymeric composition comprising reacting a mixture of at least one phenolic compound and at least one oxazoline compound in the presence of a catalytic amount of at least one ammonium salt and a tetracarbyl phosphonium salt, and optionally also in the presence of an alkyl halide is described.

Abstract: Energy polymerizable compositions comprising at least one cyanate monomer and as curing agent an organometallic compound are disclosed. The compositions are useful in applications requiring high performance, such as high temperature performance; in composites, particularly structural composities; structural adhesives; tooling for structural composities; electronic applications such as printed wiring boards and semiconductor encapsulants; graphic arts; injection molding and prepregs; and high performance binders.

Abstract: A method is provided for absorbing electromagnetic radiation using a polyaniline composition, wherein the radiation is infrared, visible light, ultraviolet, radar, or microwave radiation. Also provided is a method for reducing the detectability by radar of an object by increasing the absorption of radar waves and thereby decrease the reflection of the radar waves by applying to the object a polyaniline composition or a partially protonated salt thereof.

Abstract: Epoxy resins containing more than one vicinal epoxide group per molecule and at least one thiadiazole, oxadiazole or both thiadiazole and oxadiazole moiety per molecule are disclosed, as well as curable and cured compositions thereof. Certain of these epoxy resins possess enantiotropic liquid crystallinity. These enantiotropic epoxy resins are useful in preparing copolymers with high glass transition temperatures and liquid crystalline morphology, which can result in enhanced unidirectional mechanical properties. These epoxy resins are useful in coating, casting, encapsulation, electronic or structural laminate or composite, filament winding or molding applications.

Abstract: A process for preparing a conductive polymer article comprises the steps of preparing a dispersible neutral intrinsically conductive polymer; dispersing the intrinsically conductive polymer in a thermoplastic polymer to form a blend; processing the blend into the shape of the desired article; and, contacting the processed article with a dopant solution capable of both swelling the thermoplastic polymer and doping the intrinsically conductive polymer. A process for preparing neutral polyaniline comprises the steps of neutralizing doped polyaniline with a sodium carbonate solution and washing the polyaniline with a polyethyleneglycol solution. A conductive polymer article comprises a blend of an intrinsically conductive polymer and a thermoplastic polymer which is subsequently doped. A conductive polymer blend according to the invention, includes polyaniline, or insulating thermoplastic material and carbon black.

Abstract: Novel cyclic imino ether compositions containing one or more mesogenic moieties, when polymerized, result in products having improved properties.

Abstract: Salts that contain AA-PBZ monomer ions and BB-PBZ monomer ions can be precipitated from an aqueous solution by contacting soluble salts of the monomers in an aqueous solution. The monomer salt can be polymerized by ordinary techniques to form polybenzazole polymers without the need for devolatilization and with very accurate stoichiometric control.

Abstract: Polybenzoxazoles (PBO) are prepared by the aromatic nucleophilic displacement reaction of novel di(hydroxyphenyl)benzoxazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The polymerizations are carried out in polar aprotic solvents, such as N-methylpyrrolidine or N,N-dimethylacetamide, using alkali metal bases, such as potassium carbonate, at elevated temperatures under nitrogen. The novel di(hydroxyphenyl)benzoxazole monomers are synthesized by reacting phenyl-4-hydroxybenzoate with aromatic bis(o-aminophenol)s in the melt. High molecular weight PBO of new chemical structures are prepared that exhibit a favorable combination of physical and mechanical properties. The use of the novel di(hydroxyphenyl)benzoxazoles permits a more economical and easier way to prepare PBO than previous routes.

Abstract: A hydroxy-substituted poly(phenylene ether) resin can be produced by copolymerizing from 1.5 to 8 mol % of a phenol compound selected from those represented by the following formulae (a), (b), (c), (d), and (e): ##STR1## and from 98.5 to 92 mol % of a phenol compound of the following formula (f): ##STR2## The hydroxy-substituted poly(phenylene ether) resin shows excellent compatibility with a polyamide, a polycarbonate, a poly(butylene terephthalate), a poly(phenylene sulfide), and is useful as a copatibilizer or a modified resin for engineering plastics.

Abstract: Homopolymers and copolymers with high Tg's are produced from phthalazones which in turn are produced from phenolphthalein as a readily available starting material; the homopolymers may be represented by formula (IX): ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, are selected from hydrogen, fluorine, phenyl and fluorophenyl, each m, which may be the same or different, is an integer of 0, 1, 2, 3 or 4, and n is an integer of 2 to 200. Novel phenyl substituted phenolphthaleins and novel hydroxybenzoylbenzoic acids, as well as novel phthalazones, all of which may be employed in the preparation of homopolymers and copolymers of the invention, are also provided.

Abstract: Solder interconnection whereby the gap created by solder connections between a carrier substrate and semiconductor device is filled with a composition obtained from curing a preparation containing a cycloaliphatic polyepoxide and/or curable cyanate ester or prepolymer thereof; filler having a maximum particle size of 31 microns and being at least substantially free of alpha particle emissions.

Abstract: The present invention relates to a homogeneous accelerator system for epoxy resins and to a method of curing such epoxy resins, wherein the system comprises (a) an inorganic salt which contains a nitrate ion, (b) aliphatic hydroxy compound selected from monohydric alcohols containing 1 to 10 carbon atoms in the molecule, polyhydric alcohols containing 2 to 10 carbon atoms and 2 to 4 hydroxy groups in the molecule, and poly (C.sub.2-5 alkylene) glycols and (c) an aminophenol.

Abstract: In reactions to form PBZ polymers such as polybenzoxazole, monomers having an aromatic group bonded to a primary amine group and to a hydroxy, thio or amine group ortho to said primary amine group are contacted with monomers having an "electron-deficient carbon group." In the present invention the electron-deficient carbon group may be an alkali metal carboxylate group or a trihalomethyl group. Useful monomers include, for example, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.',-hexachloroxylene and disodium terephthalate.

Abstract: Solutions and plasticized compositions of electrically conductive substituted and unsubstituted polyanilines in nonpolar organic fluid phases with functionalized protonic acids are disclosed as are methods of forming such solutions or compositions and use of same to form conductive articles.

Abstract: A polyarylene sulfide has an inherent viscosity [.eta..sub.i n h ] of 0.1 to 0.5 dl/g, a weight-average molecular weight of 1.times.10.sup.4 to 2.times.10.sup.5 ; a ratio of the inherent viscosity [.eta..sub.i n h ] to a calculated viscosity [.eta.].sub.calc ([.eta..sub.i n h /[.eta.].sub.calc) of 0.4/1 to 0.8/1; and a degree of whiteness of 50 or higher when measured in accordance with whiteness testing procedures (JIS P8123). The polyarylene sulfide is prepared by reaction by contacting at least one member of a metallic sulfide (A) selected from an alkali metal sulfide and an alkali metal hydrosulfide with a dihalogen aromatic compound (B) and an aromatic compound (C) having three or more than three functional groups in a polar solvent in a molar ratio of the dihalogen aromatic compound (B) to the metallic sulfide (A) [(B)/(A)] ranging from 1.035/1 to 1.300/1 and in a molar ratio of the aromatic compound (C) to the dihalogen aromatic compound (B) [(C)/(B)] ranging from 0.003/1 to 0.05/1.

Abstract: The invention is a process for making novel branched polybenzazole polymers and the polymers formed thereby. Novel compounds are also disclosed that are useful as branching agents in making the branched polybenzazole polymers. The branched polymers synthesized by the process can be formed into strong, light articles such as fibers and films.

Abstract: Energy polymerizable compositions comprising at least one cyanate monomer and as curing agent an organometallic compound are disclosed. The compositions are useful in applications requiring high performance, such as high temperature performance; in composites, particularly structural composities; structural adhesives; tooling for structural composities; electronic applications such as printed wiring boards and semiconductor encapsulants; graphic arts; injection molding and prepregs; and high performance binders.

Abstract: A process for the preparation of aromatic polyamides comprises reacting carbon monoxide and an aromatic iodoamine characterized by having at least one iodine atom covalently bonded to an aromatic ring and at least one amino group. The process is conducted in the presence of a solvent, a catalyst and a base at a pressure greater than about 1 kg/cm.sup.2.

Abstract: The present invention relates to nonlinear optical material comprising nonlinear optical dihydroxy arylhydrazones and to nonlinear optical materials comprising compositions containing at least one divalent moiety of nonlinear optical arylhydrazones. The present invention also relates to polyesters, polyestercarbonates, polycarbonates, polyethers, and poly(hydroxy ether) polymers, incorporating the dihydroxy arylhydrazone as recurring divalent moieties in the backbone of the polymer. The polymeric compositions of the present invention have high glass transition temperatures and exhibit stable nonlinear optical activity at high temperatures over a period of time.

Abstract: Sulfonic acid-substituted polyaniline compositions, ammonium salts thereof, and uses therefor are disclosed. The ammonium salts of the sulfonic acid-substituted polyaniline compositions are used as interim materials in the processing of conducting sulfonated polyaniline compositions. The ammonium salts of the sulfonic acid-substituted polyaniline compositions are also used to either reversible or irreversible NH.sub.3 filters, sensors, temperature indicators and the like.

Abstract: Difficultly inflammable polymeric resins are obtained by curing resin mixtures comprising(a) a resin component comprising at least one thermically curable 1-oxa-3-aza tetraline groups containing compound; and(b) an organic metal or semimetal compound, or a carbon monoxide complex compound, of an element of the 6th, 7th or 8th auxiliary group of the periodic system or of copper, antimony or bismuth.

Abstract: The present invention provides a homogeneous accelerator system, having improved efficacy for curing epoxy resins, which comprises (A) an inorganic salt which contains a nitrate ion, (B) an aliphatic hydroxy compound selected from monohydric alcohols containing 1 to 10 carbon atoms in the molecule, polyhydric alcohols containing 2 to 10 carbon atoms and 2 to 4 hydroxy groups in the molecule, and poly (c.sub.2-5 alkylene)glycols and (C) an aminophenol accelerator.

Abstract: Biocatalytic oxidative processes wherein oxidizable substrates are reacted with peroxides in the presence of a peroxidase such as soybean peroxidase or another legume peroxidase; an oxidative coupling reaction for producing phenolic resins; a method for the purification of peroxidase enzyme-containing extracts generally also are described.

Abstract: Poly(1,2,4-triazoles)(PT) have been prepared by involving the aromatic nucleophilic displacement reaction of di(hydroxyphenyl)-1,2,4-triazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The reactions are carried out in polar aprotic solvents such as sulfolane or diphenylsulfone using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl)-1,2,4-triazole monomers are first synthesized by reacting bis(4-hydroxyphenyl) hydrazide with aniline hydrochloride at 250.degree. C. in the melt and also by reacting 1,3 or 1,4-bis-(4-hydroxyphenyl)phenylenedihydrazide with 2 moles of aniline hydrochloride in the melt. Purification of the di(hydroxyphenyl)-1,2,4-triazole monomers is accomplished by recrystallization.

Abstract: Sulfonic acid-substituted polyaniline salt compositions, processes for their preparation and uses therefor are disclosed. The sulfonated polyaniline salt compositions have fast electronic and optical responses to electrochemical potentials, improved environmental stability, and improved solubility. A process for producing the sulfonated polyaniline salt compositions comprises reacting a sulfonated polyaniline polymer with an aqueous basic solution. The sulfonated polyaniline compositions are useful for absorption of electromagnetic radiation, as a high density erasable data storage medium for use in information storage and processing applications, and to provide electronic, chemical, electrochemical, and optical microelectronic devices which use and control the chemical and physical properties of the sulfonated polyaniline salt compositions.

Abstract: Disclosed is a process for the preparation of a phenolic resin which comprises reacting a phenol with a peroxidase or an oxidase enzyme and a peroxide in an organic solvent-containing medium, wherein said phenol and said organic solvent are present at a ratio greater than about 0.5:1.

Abstract: A polyether copolymer comprising the repeating units represented by the following general formula (I) ##STR1## and the repeating units represented by the following formula (II) ##STR2## the molar ratio of (I)/{(I)+(II)} being from 0.1 to 0.8 and the polyether copolymer having a melt viscosity of at least 500 poise as measured at 400.degree. C. is produced by allowing a dihalogenobenzonitrile, 1,4-bis(4'-halobenzoyl)benzene, and 4,4'-biphenol to react with each other in an aprotic polar solvent in the presence of an alkali metal compound. The polyether copolymer exhibits excellent heat-resistance, solvent resistance, and mechanical strength, and is suitable as a material for resin compositions, heat-resistant laminates, fiber, and film.

Abstract: A method for the preparation of poly(benzoxazole)s, poly(benzimidazoles)s, and poly(benzthiazole)s. In the presence of solvent and catalyst, reacting carbon monoxide, an aromatic halide reactant having the general formula X.sup.1 --Ar.sup.1 --Z.sup.1 and an aromatic amine reactant having the general formula Z.sup.2 --Ar.sup.2 --M.sup.1, wherein X.sup.1 and Z.sup.1 are non-ortho, Z.sup.2 and M.sup.1 are non-ortho, one of Z.sup.1 and Z.sup.2 is X.sup.2 and the other one is M.sup.2, --Ar.sup.1 -- and --Ar.sup.2 -- are each independently selected from the group consisting of aromatic and heteroaromatic moieties having a total of ring carbons and heteroatoms of from 6 to about 20, X.sup.1 and X.sup.2 are each independently selected from the group consisting of --I and --Br, and M.sup.1 and M.sup.2 are each independently selected from moieties having an --NH.sub.2 radical and, ortho to the --NH.sub.2 radical, a radical selected from the group consisting of --NH.sub.2, --OH, and --SH.