Abstract: Process for the preparation of polyamides comprising the steps of A) reacting a soybean oil condensate obtained from the deodorization of refined soybean oil and which contains less than 30% by weight of free and esterified oleic acid based on the total weight of free and esterified fatty acids in said condensate, with a C.sub.1-4 alkanol in the presence of a zinc oxide catalyst to convert free fatty acids and fatty acid glyceride esters to fatty acid C.sub.1-4 alkyl esters;B) removing excess C.sub.1-4 alkanol, volatile reaction by-products, water, and the zinc oxide catalyst from the resulting reaction mixture;C) heating the reaction mixture from step B) under vacuum to obtain a distillate of fatty acid C.sub.1-4 alkyl esters;D) separating the distillate from step C) into a fraction containing mostly C.sub.16-18 saturated fatty acid C.sub.1-4 alkyl esters and a second fraction containing mostly C.sub.16-18 unsaturated fatty acid C.sub.1-4 alkyl esters wherein the oleic acid C.sub.

Abstract: An improved method for manufacturing poly(hexamethylene adipamide), i.e. nylon 6,6, by reacting monomethyl adipate with hexamethylenediamine in an approximately equimolar ratio in the presence of water at a temperature of 100 to 165.degree. C. while simultaneous distilling off of a stoichiometric amount of methanol. The resulting aqueous intermediate product is then heated to 200 to 260.degree. C. while distilling off substantially all water at a pressure of 150 to 250 psig (1.03 .times.10.sup.6 to 1.72 .times.10.sup.6 Pa) followed by reducing the pressure to atmospheric pressure and increasing the temperature to 270 to 280.degree. C. to polycondense the distillate residue. Such a process is useful in producing high purity commercial grade poly(hexamethylene adipamide) that advantageously avoids problems caused by N-methylation of the polyamide.

Abstract: A low molecular weight, ester-terminated polyamide may be blended with a liquid hydrocarbon to form a transparent composition having gel consistency. The ester-terminated polyamide is prepared by reacting "x" equivalents of dicarboxylic acid wherein at least 50% of those equivalents are from polymerized fatty acid, "y" equivalents of diamine such as ethylene diamine, and "z" equivalents of monoalcohol having at least 4 carbon atoms. The stoichiometry of the reaction mixture is such that 0.9.ltoreq.{x/(y+z)}.ltoreq.1.1 and 0.1.ltoreq.{z/(y+z)}.ltoreq.0.7. The reactants are heated until they reach reaction equilibrium. The gel contains about 5-50% ester-terminated polyamide with the remainder preferably being pure hydrocarbon. The gels are useful in formulating personal care products and other articles wherein some degree of gel-like or self-supporting consistency is desired.

Abstract: A polyamide composition which is amorphous and transparent, which has reduced flammability, and which has reduced migration of flame-retardant additive so that it is film-free, includes at least one polyamide which contains cycloaliphatic monomer units and which is amorphous and transparent; and a flame-retardant additive which is present in an amount effective to reduced flammability of the polyamide composition, which is dissolved in the at least one polyamide, and which is at least one alkyl phosphonic acid compound having a general formula: ##STR1## wherein R and R' each represent, independent of each other, an alkyl group having from 1 to 4 carbon atoms, and x=0 or 1. An article molded from this composition is transparent, has reduced flammability, and has reduced migration of flame-retardant additive so that it is film-free.

Abstract: This invention relates to high temperature, semi-crystalline, semi-aromatic nylon terpolymers with improved shrinkage resistance, made from terephthalic acid (TA), hexamethylene diamine (HMD) and/or 2-methyl pentamethylene diamine (2-MPMD) and another aliphatic dicarboxylic acid as monomers. These polymers display superior % TD (Transverse Direction) annealing shrinkage, as well as very good balance of mechanical performance as high temperature nylons.

Abstract: In a process for the preparation of poly-o-hydroxyamides and poly-o-mercaptoamides, a bis-o-aminophenol or a bis-o-aminothiophenol is reacted with a dicarboxylic acid derivative of the following structure: ##STR1## with D=O, S, or NH and where R* is the parent body of the dicarboxylic acid and at least one of the groups R.sup.1 and R.sup.2 is CN or NO.sub.2.

Abstract: Improved high temperature polyamides, and particularly partially-aromatic polyamides, containing less than about 40 .mu.eq/g carboxylic acid endgroups. When stabilized with a copper-containing thermal stabilizer, the polyamides exhibit improved thermal oxidative stability.

Abstract: It has been found that fibers which incorporate very good mechanical properties as well as very good adhesive properties can be made from an optically anisotropic spinning solution containing a mixture of a paraphenylene groups-containing, wholly aromatic polyamide component and another polyamide component if for the para-aromatic polyamide component full or partial use is made of copolymer in which 2,6-naphthylene units are present in addition to the paraphenylene units and the other polyamide component is an aliphatic polyamide. Preferably, the weight ratio of the para-aromatic polyamide component to the aliphatic polyamide component is 95:5 to 85:15. The aromatic copolyamide containing paraphenylene and 2,6-naphthylene is preferably obtained by polymerising paraphenylene diamine (PPD) and a stoichiometric amount of a mixture composed of terephthalic acid dichloride (TDC) and 2,6-naphthylene carboxylic acid dichloride (NDC) in a molar ratio TDC:NDC of 99:1 to 80:20.

Abstract: Polyamides are built up from, as fundamental building blocks (a), lactams or aminocarboxylic acids or mixtures of these,as fundamental building blocks (b), from 1 to 50 .mu.mol of at least tribasic amines or carboxylic acids per gram of polyamide,as fundamental building blocks (c), dibasic carboxylic acids or amines andas fundamental building blocks (d), monobasic carboxylic acids or amines,where (c) and (d) are carboxylic acids if (b) are amines, and (c) and (d) are amines if (b) are carboxylic acids,the equivalents ratio of the functional groups of (b) to the functional groups of (c) and (d) together is from 60:40 to 40:60 andthe equivalents ratio of the functional groups of (c) to the functional groups of (d) is from 15:85 to 60:40.

Abstract: Disclosed is a polymeric composite material in which metal sulfide microparticles having optical characteristics are uniformly dispersed and suspended in a high polymer material at high concentration. The polymeric composite material comprises metal sulfide microparticles formed by a reaction of a functional group in a matrix forming material having the functional group, the metal sulfide microparticles being dispersed in a matrix. It is desirable that the matrix includes a compound having the structure represented by formulae (1) to (5).

Abstract: A process is provided for preparing a dispersion of a polyamide in water, said process comprising:forming a solution of a polyamide having an acid value of greater than about 2 in an organic solvent to form a solution of said polyamide in said solvent, said polyamide and said solvent being at a temperature below the softening point of said polyamide during said dissolving, said solution further comprising a surfactant, wherein at least a portion of the acid value of said polyamide is neutralized,adding sufficient water to said solution with mixing to form an oil-in-water dispersion, the temperature of said solution and said water being below the softening point of said polyamide during said adding, andremoving at least a major amount of said organic solvent from said oil-in-water dispersion. The resulting dispersion is useful in preparing a coating of the polyamide, which coating is useful as an adhesive.

Abstract: A method for binding ceramic materials in aqueous media is disclosed. The method utilizes water-soluble polyamides prepared by condensation polymerization for binding various classes of ceramic materials.

Abstract: An uncoated lens, especially for use as the lens of a fog light or a headlight for an automobile, and having particularly good resistance against the environmental effects which are inherent in this environment, is formed of a colorless, transparent copolyamide having a glass transition temperature of at least a 170.degree. C., blended with a homopolyamide, and wherein the copolyamide is formed from at least one cycloaliphatic diamine with two cyclohexane rings, and at least one aromatic dicarboxylic acid which is predominantly isophthalic acid. The copolyamide may optionally contain up to 20 mol % of a further polyamide forming monomer of at least one lactam or an omega-aminocarboxylic acid. The homopolyamide is preferably one of PA6, PA11, PA12, PA66, PA69, PA610 or PA612. The cycloaliphatic diamine of the copolyamide is preferably bis(3-methyl-4-aminocyclohexyl)-methane.

Abstract: A method for binding ceramic materials in aqueous media is disclose. The method utilizes water-soluble polyamides prepared by condensation polymerization for binding various classes of ceramic materials.

Abstract: Aromatic polyimide powder wherein a solid portion consisting of a highly heat resistant crystalline aromatic polyimide is covered with a coating layer of an amorphous polyimide, and a process for producing polyimide powder molded bodies by compression molding of the powder. The polyimide powder has satisfactory secondary molding workability, and molding thereof gives molded bodies which retain heat resistance and dimensional stability while having high mechanical strength and elongation.

Abstract: A copolyamide composition prepared from hexamethylene diamine and either mixtures of adipic acid and terephthalic acid, or mixtures of adipic acid, terephthalic acid and isophthalic acid, has a melting point below 320.degree. C., a glass transition temperature between 100.degree. C. and 120.degree. C. and physical properties similar to nylon 66.

Abstract: A process is provided for preparing a dispersion of a polyamide in water, said process comprising:dissolving a polyamide having an amine value of greater than about 2 in an organic solvent to form a solution of said polyamide in said solvent, said polyamide and said solvent being at a temperature below the softening point of said polyamide during said dissolving, said solution further comprising a surfactant and an inorganic alkaline material,adding sufficient water containing an acid to said solution with mixing to form an oil-in-water dispersion, the temperature of said solution and said water being below the softening point of said polyamide during said adding, the amount of said acid being sufficient to neutralize a portion of said inorganic alkaline material, but insufficient to coagulate said polyamide from the resulting oil-in-water dispersion, andremoving at least a major amount of said organic solvent from said oil-in-water dispersion.

Abstract: Pyrrolidonyl-containing polyesters and polyamides I to III ##STR1## where R, X, A and Z are defined herein, are suitable as film formers and conditioners in hair-cosmetic formulations, for stabilizing hydrogen-peroxide in aqueous solution, for complexing iodine, as tablet binders and as a constituent of film coatings in pharmaceutical preparations, for enzyme and bleach stabilization in detergent formulations, as an auxiliary in the production and finishing of textiles, as a solubilizer and protective colloid in the preparation and stabilization of polymer dispersions, and as an adhesive raw material.

Abstract: A water solvent extraction degreasing method capable of reducing degreasing time without consideration of abrupt decomposition/vaporization and swelling caused by heat. An organic binder is removed from a molded product that is produced by a powder material mixed with the organic binder and this organic binder contains at least one water-soluble organic compound and at least one water-insoluble thermoplastic resin. The degreasing step of this method includes a water solvent extraction step for extracting the water-soluble organic compound from the organic binder contained in the molded product, using water as a solvent.

Abstract: This invention relates to a nonwoven web and fibers comprising a water soluble polyamide and articles constructed therefrom. The water soluble polyamide may be used alone or in combination with conventional thermoplastic web and fiber forming materials such as water insoluble polyethylene, polypropylene, polyester and polyamide. The water soluble polyamide may also be combined with biodegradable or selectively dispersible material to form nonwoven webs and fibers having various combinations of properties. Such water soluble webs and fibers have utility in the manufacture of disposable absorbent articles such as disposable diapers, feminine napkins, incontinent products and cellulosic articles such as tissues and towels, as well as for water soluble heat fusible webs for the textile industry.

Abstract: This invention relates to a nonwoven web comprising a water soluble polyamide and articles constructed therefrom. The water soluble polyamide may be used alone or in combination with conventional thermoplastic web forming materials such as water insoluble polyethylene, polypropylene, polyester and polyamide. The water soluble polyamide may also be combined with biodegradable or selectively dispersible material to form nonwoven webs having various combinations of properties. Such water soluble webs have utility in the manufacture of disposable absorbent articles such as disposable diapers, feminine napkins, incontinent products and cellulosic articles such as tissues and towels, as well as for water soluble heat fusible webs for the textile industry.

Abstract: A method of making paper in which dry chemical additives are incorporated into the pulp mixture by addition of an entire bag containing the additive directly to the mixture, the improvement being that the bag is sealed with an adhesive closure, the adhesive being a hot melt consisting essentially of a water dispersable polyamide prepared from a diacid component comprising in major portion an aliphatic diacid of 6 or fewer carbon atoms and a diamine component consisting of one or more compounds of the formula :H.sub.2 N--C.sub.y H.sub.2y --(OC.sub.2 H.sub.4).sub.x --O--C.sub.y H.sub.2y --NH.sub.2where y is 2 or 3 and x is 1-50 and a wax. Such bags will not leak in shipping and handling, and yet can be added directly to paper batches at ambient temperature in the manner of the unsealable bags employed in the prior art.

Abstract: A low-cost thermal decomposition degreasing method capable of drastically reducing the time required for a degreasing process which involves heating, vaporization and thermal decomposition, while assuring the shape retention property of an injection molded product during degreasing. The degreasing process comprises: (i) a first step wherein a molded product placed under a reduced pressure less than or equal to atmospheric pressure is heated at a temperature lower than the melting point of a thermoplastic binder so that the thermoplastic binder partially evaporates by 5 wt % or more, and then the molded product is further heated at a temperature lower than higher one of the melting points of a more volatile organic compound and a thermoplastic resin whereby the thermoplastic binder further evaporates by 10 wt % or more, and wherein the final temperature is set to 200.degree. C.

Abstract: The semiaromatic polyamide of the invention comprises 40 to 90% by mol of (A) recurring units derived from terephthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 50% by mol of (B) recurring units derived from isophthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 60% by mol of (C) recurring units derived from an aliphatic dicarboxylic acid of 4 to 18 carbon atoms and an aliphatic diamine of 4 to 12 carbon atoms and 0 to 50% by mol of (D) recurring units derived from a lactam or an aminocarboxylic acid of 6 to 20 carbon atoms, and has a content of boiling water-soluble components (MO components) of not more than 0.25% by weight. The semiaromatic polyamide has a low content of the MO components, so that mold contamination hardly brought about in the molding process, and also molded articles of good heat resistance can be produced.

Abstract: A method of producing a polyamide resin by reacting 1 mol of linear polyester resin (as calculated in repeating unit of the linear polyester resin) consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g with 0.5-1.5 mol of at least one diamine compound in a reaction medium comprising at least one solvent which is selected from the group consisting of hydrocarbons, halogenated hydrocarbons, ethers and acetals, so that the diol component of the linear polyester resin is substituted by the diamine compound to provide the polyamide resin as a reaction product.

Abstract: Synthetic filaments include a nonaqueous additive system having dispersant-coated pigments physically dispersed in a liquid nonaqueous polymeric carrier. The additive system is most preferably in the form of a particulate paste which can be added in metered amounts (dosed) to a melt flow of the polymeric host material prior to being spun into filaments. By providing a number of additive systems having a number of different additive attributes, and controllably dosing one or more into the melt flow of polymeric material, melt-spun filaments having different additive attributes may be produced on a continuous basis (i.e., without shutting down the spinning operation). The filaments may be included in yarns which are formed into carpet structures.

Abstract: Colorless, amorphous polyamide, or blends or alloys thereof, and the molded articles with high alternate bending strengths are made available; they are preferably made up of unbranched aliphatic diamines and cycloaliphatic dicarboxylic acids, and have high strength, high rigidity, high heat distortion, and good solvent resistance.

Abstract: Improved high temperature polyamides, and particularly partially aromatic polyamides, containing less than about 40 .mu.eq/g carboxylic acid endgroups, when stabilized with a copper-containing thermal stabilizer, the polyamides exhibit improved thermal oxidative stability.

Abstract: A copolyamide composition prepared from hexamethylene diamine and mixtures of adipic acid, terephthalic acid and isophthalic acid, has a melting point below 300.degree. C., a glass transition temperature between 100.degree. C. and 130.degree. C. and physical properties similar to nylon 66.

Abstract: An insulated electrical wire coated with a polyamide-imide insulating material which is a copolymer of anhydrotrimellitic acid, aliphatic and aromatic dicarboxylic acids and a diisocyanate, with a molar ratio of the acids to the diisocyanate of from about 0.9:1.0 to about 1.1:1.0 and optionally further containing from about 1 part wt. to about 30 parts wt. of an epoxy resin per each 100 parts of the copolymer. Optionally the aforementioned insulation can be an interior, first coating, coated by a second coating of a polyamide, polyamide-imide, and when the first coat does not contain an epoxy, then a polyimide.

Abstract: A polyamide resin composition having good molding fluidity, heat and chemical resistance and dimensional stability is provided containing: (A) 30-90 weight percent, based on components (A) and (B), of a polyamide resin containing (i) 10-99 weight percent, based on components (i) and (ii) of an aromatic polyamide containing a carboxylic acid component derived from terephthalic acid or a mixture of terephthalic and isophthalic acid in which the isophthalic acid constitutes 40 mole percent or less of the mixture, and an aliphatic diamine component derived from a mixture of hexamethylene diamine and 2-methylpentamethylene diamine; and (ii) 1-90 weight percent, based on components (i) and (ii), of at least one polyamide selected from the group consisting of polyamides containing repeat units derived from alipathic dicarboxylic acids and alipathic diamines and polyamides containing repeat units derived from aliphatic aminocarboxylic acids; and (B) 10-70 weight percent, based on components (A) and (B), of an inorgan

Abstract: This invention relates to a novel ternary polyamide for the production of monofilaments, films and injection moulded articles.

Abstract: A partially aromatic copolyamide is formed of:(a) 5 to 30 weight-% of hexamethylene diamine(b) 10 to 40 weight-% of metaxylylene diamine(c) 15 to 50 weight-% of adipic acid(d) 5 to 45 weight-% of at least one aliphatic dicarboxylic add with 7 to 10 carbon atoms, preferably sebacic acid and/or acelaic acid, wherein the components (a) to (d) add up to 100 weight-%, and the add groups and the amine groups are essentially present in equimolar portions. These novel copolyamides are used for producing barrier layers for mono- or multi-layered composites, such as foils or containers, infusion- or ostomy bags, shrink wraps for meat, fish and cheese packagings or sausage skins, wherein the copolyamides can be present in the pure form or as a mixture with other polymers, in particular in combination with further polymer layers.

Abstract: A process for producing precondensates of partially crystalline or amorphous, thermoplastically processable, partially aromatic polyamides or copolyamides, and the use of the higher molecular weight of polyamides, accessible from the precondensates, for producing molding compositions, which are further processable by means of suitable processing techniques, involves the control of temperature and water vapor partial pressure, in a batch process.

Abstract: A copolyamide with an improved modulus of elasticity for the melt-spinning of filaments consists of at least 75 wt. % of a linear polyamide base polymer with a melting point of 150.degree.-320.degree. C. and at least 0.5 wt. % of a block comonomer which is incorporated into the base polymer and has a glass transition temperature (T.sub.g) between 130.degree. and 330.degree. C. and a degree of polymerization (DP) of <100. The filaments produced from the modified copolymer with an initial modulus of 500 to 1500 cN/tex are suitable for use in the production of technical fabrics.

Abstract: Partly aromatic semicrystalline thermoplastic polyamide molding compositions containA) from 40 to 100% by weight of a copolyamide composed ofa.sub.1) from 30 to 44 mol % of units which are derived from terephthalic acid,a.sub.2) from 6 to 20 mol % of units which are derived from isophthalic acid,a.sub.3) from 43 to 49.5 mol % of units which are derived from hexamethylenediamine anda.sub.4) from 0.5 to 7 mol % of units which are derived from aliphatic cyclic diamines of 6 to 30 carbon atoms,the molar percentages of components a.sub.1) to a.sub.4) together giving 100%, andB) from 0 to 50% by weight of a fibrous or particulate filler,C) from 0 to 30% by weight of an elastomeric polymer andD) from 0 to 30% by weight of conventional additives and processing assistants,the percentages by weight of components A) to D) together giving 100%.

Abstract: Certain polyamide resin compositions make it possible to shorten the injection molding processing cycle for polyamide resins. The polyamide resin compositions are obtained by adding an external lubricant to polyamide resin granules composed of from 55 to 85% by weight of polyamide resin, 10 to 40% by weight of filler, and 0.3 to 2.0% by weight of at least one type of higher fatty acid ester type internal lubricant selected from among esters of higher alcohols and higher fatty acids and higher fatty acid partial esters of polyhydric alcohol compounds.

Abstract: Colorless, transparent copolyamides, made up of monomers based on cycloaliphatic diamines and aromatic dicarboxylic acids and a maximum of 20 mol % of further polyamide-forming aliphatic monomers, which have glass transition temperatures of at least 175.degree. C., their blends and alloys, along with the molded articles that can be produced from them and a process for their preparation are proposed.

Abstract: Shaped articles are obtained from a polymerization mixture of soluble wholly aromatic polyamides in a gel state.

Abstract: The resin composition of the present invention allows the molding of a hollow molded product, able to stably form a long parison and having a three-dimensionally curved shape, by the formation of a copolyamide having a melting point of 225.degree. C. or more and a crystallization temperature of 230.degree. C. or less obtained by a polymerization of 66, 6T and 6I components at a specific compounding ratio.

Abstract: A process for the continuous production of polyamides from a mixture of at least one lactam and water and, if required, other monomer units and/or conventional additives and fillers under polyamide-forming conditions, where the mixture of the starting materials is heated in liquid phase in a first reaction zone until a conversion of at least 70% is reached, and undergoes adiabatic decompression and further polymerization in another reaction zone, wherein, in the first reaction zone, 0.5-7% by weight of water are employed, the temperature is increased to the range from 220.degree. to 310.degree. C., and polymerization is carried out until a conversion of at least 85% is reached and, in the second reaction zone, after the decompression further polymerization is carried out in the range from 215.degree. to 300.degree. C. without heat input.

Abstract: The invention provides a continuous process for the preparation of polyamides, equipment in which the polymerization process can be conducted, and process control methods for said polymerization process.

Abstract: A polyamide hot melt adhesive is provided. It comprises the polyamide condensation product of substantially equivalent quantities of (a) an acid component consisting essentially of one or more polymeric fatty acids and one or more dicarboxylic acids and (b) an amine component consisting essentially of (i) two or more non-cyclic aliphatic diamines and (ii) one or more amine-terminated polyglycol diamines. The amine component is substantially free of piperazine-containing polyamines. The adhesive has an open time of at least 120 seconds. Preferred non-cyclic aliphatic diamines are ethylenediamine and 1,6-diaminohexane, preferably present in about equimolar amounts. The composition may further comprise an aromatic sulfonamide plasticizer. The adhesive is particularly useful for spraying applications.

Abstract: A low temperature process for polymerizing nylon monomers to freely flowing polymers is disclosed. The polymerization process is carried out at lower than conventional polymerization temperatures and produces a freely flowing polymer without thermal degradation.

Abstract: A copolymerized polyamide, comprising amide bonds formed by an aliphatic diamine with 4 to 14 carbon atoms and terephthalic acid, with the existence ratios of distributed respectively adjacent amide bonds satisfying the following formulae (A) and (B), and with the half-crystallization time satisfying the following formula (C).0.9.ltoreq.[XY]obs./[XY]calcd.<1.1 (A)0.9.ltoreq.[XX]obs./[XX]calcd.<1.1 (B)wherein X stands for an amide bond formed by an aliphatic diamine with 4 to 14 carbon atoms and terephthalic acid, and Y stands for any other amide bond than X. [XY] refers to the rate at which X and Y are adjacent to each other among all the amide bonds in the polymer structure, and [XX] refers to the rate at which X and X are adjacent to each other among all the amide bonds in the polymer structure. [XY] calcd. and [XX] calcd. are respectively the values of [XY] and [XX] calculated on the assumption that X and Y amide bonds are distributed statistically at random, and [XY] obs. and [XX] obs.

Abstract: This invention relates to a nonwoven web comprising a water soluble polyamide and articles constructed therefrom. The water soluble polyamide may be used alone or in combination with conventional thermoplastic web forming materials such as water insoluble polyethylene, polypropylene, polyester and polyamide. The water soluble polyamide may also be combined with biodegradable or selectively dispersible material to form nonwoven webs having various combinations of properties. Such water soluble webs have utility in the manufacture of disposable absorbent articles such as disposable diapers, feminine napkins, incontinent products and cellulosic articles such as tissues and towels, as well as for water soluble heat fusible webs for the textile industry.

Abstract: In a process for producing filler-containing thermoplastic molding compositions by mixing fillers with thermoplastics in the melt,a) the fillers are mixed in a mixing apparatus in the melt with a low molecular weight thermoplastic having a melt viscosity of at most 30 Pas (measured at 20.degree. C. above the melting point of the thermoplastic compound and at a shear gradient of 1,000 s.sup.-1),b) the product thus obtained is removed from the mixing apparatus, cooled and comminuted, andc) the comminuted product is then subjected in the solid phase to a post-condensation.

Abstract: A process for the copolymerization of (1) a carboxylic acid comprising terephthalic acid and mixtures thereof with isophthalic acid with (2) a mixture of hexamethylene diamine and 2-methyl pentamethylene diamine. The pressure in the polymerization process is maintained at at least about 2.15 MPa for a period of at least about 40 minutes so that the resultant copolyamide, when annealed, has less than 1% by weight based on the total weight of the copolyamide of fractions having melting points greater than 320.degree. C. Use of lower pressures and times tends to result in formation of a high melting fraction.

Abstract: Polyesters obtained by reacting from 5 to 50 parts of at least one linear or branched, aliphatic or cycloaliphatic, at least dihydric alcohol, from 2 to 40 parts of at least one at least dibasic, aromatic carboxylic acid, from 0 to 40 parts of at least one 2-alkenyldicarboxylic anhydride, from 10 to 30 parts of at least one at least dibasic, linear or branched, aliphatic carboxylic acid, from 0 to 15 parts of an aliphatic, linear or branched hydroxy acid, from 0 to 15 parts of an aliphatic, linear or branched polyamine having at least one primary and at least one secondary or tertiary amino group, from 0 to 15 parts of a glycidyl ester of a branched, aliphatic monocarboxylic acid or of a glycidyl ether of a branched, aliphatic alcohol, and from 0 to 15 parts of polyhydroxyamine are useful, for example, as additives in coating compositions.

Abstract: A polymer having repeating units of the formula: ##STR1## wherein Q is ##STR2## wherein X is --NH--, --S-- or --O--. A copolymer having repeating units of the formula: ##STR3## wherein x has a value of 0.01 to 0.99 and Q is ##STR4## wherein X is --NH--, --S-- or --O--.