Abstract: Colpolyamides resulting from the polycondensation of a mixture of (a) dodecanelactam (L12) or of 12-aminododecanoic acid (A12) and of (b) 11-aminoundecanoic acid (A11) are characterized in that the monomer L12 or A12 represents 1 to 15% or 85 to 99% by weight of the mixture, and the copolyamides have melting points (mp) as a function of the composition, the units originating from the monomer A12 and L12 being in a majority or minority respectively:(1) A12 or L12 is a majority: mp (.degree. C.).gtoreq.176-0.567.times.(% A11)(2) A12 or L12 is a majority: mp (.degree.).gtoreq.187-0.5.times.(% A12 or L12),the melting points being determined by taking the peaks of the exotherm signals obtained in differential thermal analysis with a rate of heating of 10.degree. C./minute for the second heating run. Such copolyamides have a property of resilience at low temperature and a property of improved suppleness, especially when plasticizer is added to them.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 .mu.m, provided further that the number average ratio of particles smaller than 53 .mu.m is greater than 80%, the remaining larger particles being in the size range from 53 .mu.m to 180 .mu.m. A powder with slow recrystallization rates, as evidenced by non-overlapping or slightly overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10.degree. C. to 20.

Abstract: A process and device for the standardised continuous production of polyamide 6, polyamide 6.6 and/or copolyamides from e-caprolactam and/or adipic acidic hexamethylenediamine or adipic acid and hexamethylenediamine uses a combination of known specific processes to design a polymerisation reactor in which product with sufficiently high quality can be produced with the most efficient possible use of the energy applied and in such a way that the initial substances can be used alternately in the individual processing stages: pre-heating of the initial products using a common heat exchanger to 190-300.degree. C.; polymerisation of the initial products in a pressure stage with or without elimination of water and product recycling at 150-280.degree. C. and a pressure of <20 bar, dewatering of the polymer melt in a one to five turn coil under slow pressure reduction; and final condensation of the melt in at least one common vertical reactor at temperatures of between 210 and 285.degree. C.

Abstract: Disclosed is a process for preparing spherical polyamide having an average grain diameter of 100 .mu.m or less which comprises polymerizing monomers for preparing the polyamide under heating at a temperature higher than the melting points of the monomers and the polyamide while melting the monomers in a polymerization medium under stirring whereby dispersing the formed polyamide with fine particles in the polymerization medium and then cooling the resulting mixture.

Abstract: A process and a device for continuous production of polyamides from a monomer starting material consisting (up to 100%) of adipic acid hexamethylene diamine and water are described. The process is characterized by completing of the first step under pressure at temperatures between 180 and 280.degree. C. in a closed reactor, after which the polyamide is subjected to further steps at the start of each of which vaporized water is removed or driven out by an inert gas.

Abstract: A two-step process for the production of polyamides from .alpha.,.omega.-dinitriles and .alpha.,.omega.-diamines involving the catalytic hydrolysis of the .alpha.,.omega.-dinitrile by addition of water with simultaneous purging of the reactor (i.e., venting of ammonia and water vapor) in the first step followed by polymerization by addition of the .alpha.,.omega.-diamine to the hydrolysate in the second step. Such a process is particularly useful in the production of poly(hexamethylene adipamide), i.e., nylon 6,6, from adiponitrile and hexamethylene diamine using lower catalyst levels during hydrolysis and resulting in reduced levels of bis(hexamethylene)triamine, BHMT, in the polymer.

Abstract: The invention comprises a process of producing .epsilon.-caprolactam from extract water of polycaprolactam obtained by hydrolytic polymerization, wherein(i) the extract water is concentrated by distillation of water,(ii) from the concentrated extract water from stage (i) an extract of .epsilon.-caprolactam and oligomers including dimers is obtained by separating an .epsilon.-caprolactam/water vapor mixture,(iii) the extract from stage (ii) is depolymerized in the presence of a catalyst and superheated steam, where a vapor mixture of .epsilon.-caprolactam and water is obtained, and(iv) from the .epsilon.-caprolactam/water vapor mixtures of process stages (ii) and (iii) .epsilon.-caprolactam with a dimer content of .ltoreq.0.2 wt-% is obtained by distillation of water.

Abstract: A process for the hydrolysis of a dinitrile (e.g., adiponitrile) utilizing from 0.1 to 500 mmoles of catalyst (e.g., a mixture of phosphorous acid and calcium hypophosphite) per mole of the dinitrile and in the presence of from 0.01 to 0.5 moles of a dicarboxylic acid cocatalyst (e.g., adipic acid) followed by addition of a diamine (e.g., hexamethylenediamine) and heating to produce polymerization. Such a process is particularly useful in the production of nylon 6,6 having a low BHMT content and improved melt stability.

Abstract: A process for the hydrolysis of a dinitrile (e.g., adiponitrile) utilizing a dicarboxylic acid (e.g., adipic acid) as the sole catalyst followed by addition of a diamine (e.g., hexamethylenediamine) and heating to produce polymerization. Such a process is particularly usefull in the production of nylon 6,6 having a low BHMT content and improved melt stability.

Abstract: The invention relates to an acid-dyeable polyamide fiber which can be obtained very reproducibly and unsusceptibly to faults during the production process. The fiber is characterized in that the amino end group content is less than 10 meq/kg. A very reproducible affinity for dyestuffs is obtained by copolymerization of a compound containing an acidic end group and having a basic nature. Compounds derived from melamine are particularly suitable.

Abstract: Disclosed is a process for the preparation of polyamide polymers via prepolymer formation in a reactor system comprising a reactor, flasher and separator, crystallization of the prepolymer under controlled temperature conditions and the subsequent conversion of these crystallized prepolymers to high molecular weight polymer.

Abstract: Copolymers containing N-vinyllactam derivatives protected at 3-position are provided and represented by the following formula. The copolymers are used as a photoresist material suitable for deep uv process so that high sensitivity and resolution can be obtained. In addition, ultrafine circuits can be formed and an exceptional improvement in PED stability can be accomplished by use of the photoresist.

Abstract: A method of forming a polyamide from a corresponding nylon salt material comprises providing a reaction mixture comprising a nylon salt and carbon dioxide; and then condensing the nylon salt in the carbon dioxide to form a polyamide and water. A method of forming a polyamide comprises providing a reaction mixture containing at least one lactam monomer and carbon dioxide; and then polymerizing the lactam monomer in the carbon dioxide to form a polyamide.

Abstract: A method for the production and use of a catalytically-acting liquid system is offered, which has no or only a small proportion of free lactam, and which is of low viscosity and good storage stability and which directly initiates the anionic lactam polymerization.

Abstract: The present invention relates to a mixture of polymers (A) having polyamide blocks and copolymers (B) comprising vinylaromatic units and unsaturated carboxylic anhydride units, the quantity of (B) being sufficient for the melt index (or melt flow index, MFI) of the mixture of (A) and (B) to be less than the melt index of (A) alone.It also relates to masterbatches of (A) and (B).

Abstract: A method for manufacturing shaped parts by polymerization of lactams in a mold includes the steps of providing a melt consisting of at least one catalyst, at least one activator, and amino-terminated polyethers in a mold and providing as the catalyst a 17% by weight solution of sodium lactamate in an amount of 1.0 weight-% to 3.8 weight-%.

Abstract: Claimed is a copolyether amide having a melting point in the range of 180.degree. to 260.degree. C., incorporating at least 10 wt. % and not more than 30 wt. % of ethylene oxide groups, and composed of 30 to 60 wt. % of polyamide segments and 70 to 40 wt. % of segments derived from a (cyclo)aliphatic or aromatic dicarboxylic acid or a dimeric fatty acid and a polyoxyalkylene diamine derived from a polyoxyalkylene group having a molecular weight of 600 to 6000 and an atomic ratio of carbon to oxygen of 2.0 to 4.3. Also claimed is a non-porous, waterproof film having a water vapor permeability of at least 1000 g/m.sup.2 day determined at 30.degree. C. and 50% RH in accordance with ASTM E96-66 which is based on a the use of these films in rainwear, shoes, tents, chairs, as mattress covers and underslating, for medical purpose garments, and for the manufacture of dressings.

Abstract: A laser-sinterable powder product has been prepared having unique properties which allow the powder to be sintered in a selective laser sintering machine to form a sintered part which is near-fully dense. For most purposes, the sintered part is indistinguishable from another part having the same dimensions made by isotropically molding the powder. In addition to being freely flowable at a temperature near its softening temperature, a useful powder is disclosed that has a two-tier distribution in which substantially no primary particles have an average diameter greater than 180 .mu.m, provided further that the number average ratio of particles smaller than 53 .mu.m is greater than 80%, the remaining larger particles being in the size range from 53 .mu.m to 180 .mu.m. A powder with slow recrystallization rates, as evidenced by non-overlapping endothermic and exothermic peaks in their differential scanning calorimetry characteristics for scan rates of on the order of 10.degree. C. to 20.degree. C.

Abstract: A method for manufacturing a sheet molded part by polymerization of lactams in a sheet mold includes the steps of placing a fiber composite material into a sheet mold having large plane surfaces and fixedly positioning the fiber composite material in the sheet mold. Subsequently, the lactams are introduced into the sheet mold and the lactams are polymerized.

Abstract: The invention concerns a process for continuously preparing polyamide 6 with a low dimer content from .epsilon.-caprolactam (fresh lactam) and/or from recycled lactams from extraction and melt-demonomerizing stages. In a plurality of process stages the recycled lactam and/or fresh lactam is hydrolyzed under pressure in the fusible state with water contents of between 3 and 15% and temperatures ranging from 220.degree. C. to 280.degree. C. With a lower constant water content being set, the molten polyamide is then fed to the polymerization process in a further pressure stage incorporating a gas chamber.

Abstract: Disclosed herein are cyclic oligomers comprising substituted or unsubstituted m-phenylene isophthalamide, complexes of these oligomers with selected metal salts, novel methods for their preparation, and polymerization of the cyclic oligomers to linear aramids. The aramids are useful, for example, as fibers for fire resistant clothing. Amino-functional cyclic oligomers may be reacted with polyfunctional acyl halides to produce polyamides.

Abstract: The invention relates to electrical and electronic components made of a polyamide composition and possessing an improved resistance under soldering conditions, particularly when the surface mounting technique is used. This is achieved by using a polyamide composition whose main chain essentially consists of units derived from aliphatic dicarboxylic acids and diamines or .alpha.,.omega.-amino acids, and in which 1-40% of the chain units are derived from 1,6-cyclohexanedicarboxylic acid and an aliphatic diamine, or from 1,4-cyclohexanediamine and an aliphatic dicarboxylic acid.As a result, the temperature at which blisters are formed during soldering by the infrared method is 20-30.degree. C. higher than in the case of the homo-polyamide.

Abstract: The invention concerns a method of continuously producing polyamide 6 using recycled lactam from extraction and melt-demonomerizing stages. According to the invention, the cyclic oligomers present in the recycled lactam owing to the addition of .epsilon.-caprolactam (fresh lactam) are dissolved in the lactam as a function of the concentration of the oligomers in the product in use, at a dissolution temperature of between 120.degree. C. and 180.degree. C. The solution is then passed to a treatment, the solution preferably being introduced into a closed system and hydrolyzed in the fusible phase under pressure, at water contents of between 3 and 15% and temperatures ranging from 220 to 280.degree. C. With a constant low water content being set, the melt is then fed to the polymerization process in a further pressure stage incorporating a gas chamber (polymerizator).

Abstract: An improved method for increasing the relative viscosity and molecular weight of a polyamide polymer (such as nylon 6,6, nylon 6, and the like) while in the solid state involving the use of a phosphorus-containing catalyst (such as 2(2'-pyridyl) ethyl phosphonic acid or the like) in combination with an oxygen free gas characterized by a low dew point (typically below 30.degree. C. and preferably below -30.degree. C.). The combination of affording commercial operation at greater through put at lower temperature. Such a process is of particular value during the production of terpolyamide and multipolyamide polymer intended for use in colored nylon fiber manufacture.

Abstract: N-vinyllactam derivatives protected at the 3-position are provided and represented by the following formula (I). These are polymerized into homo- and copolymers for use in microlithography of semiconductor manufacture. The polymers are used as a photoresist material suitable for a deep UV process so that pictures of high sensitivity and high resolution can be obtained. In addition, ultrafine circuits can be formed and an exceptional improvement in pattern formation can be accomplished through the use of the photoresist of the invention.

Abstract: Degradable polyesteramide suitable for use in biomedical applications is obtained by reacting diamino alkyl ester with alpha hydroxy acid to form diamide-diol which is reacted with acyl halide or dicarboxylic acid to yield polyesteramide.

Abstract: A manufacturing process of continuously producing a polyether-ester amide elastomer, which is adapted for mass production and reducing manufacturing cost, includes the steps of melting a poly (tetra methylene ether) glycol reactant, a .epsilon.-caprolactam reactant and an adipic acid reactant, pre-polymerizing the melted reactants by esterification and ring-opening reaction to form a pre-polymer and highly polymerizing the pre-polymer to form the polyether-ester amide elastomer. The polyether-ester amide elastomer is specifically used as a raw ingredient for producing a polyether-ester amide elastic fiber by drying the polyether-ester amide elastomer in a drying device, extruding the dried polyether-ester amide elastomer by an extruder, and molten spinning the extruded polyether-ester amide elastomer to form the polyether-ester amide elastic fiber.

Abstract: Polyesteramides having amino acid-derived groups alternating with hydroxy acid-derived groups are useful in making shaped articles, particularly, shaped articles suitable for use as surgical devices.

Abstract: Cyclic monomers prepared by novel methods are useful in making polyesteramides which can be made into shaped articles, particularly, shaped articles suitable for use as surgical devices.

Abstract: A polyesteramide suitable for use in the fabrication of absorbable surgical devices such as monofilament and multifilament sutures, films, sheets, plates, clips, staples, pins, screws, and the like, is obtained by reacting a monoalkanolamine such as ethanolamine with a diacid halide such as succinic acidchloride to provide a diamidediol and thereafter reacting the diamidediol with the same or different diacid halide under polymerization conditions to form the polyesteramide.

Abstract: A process for producing composite materials which can be thermally postformed, with a matrix of polylactam produced by means of activated anionic polymerization is offered.

Abstract: A process for making stain resistant nylon fibers from a mixture of nylon and highly sulfonated nylon copolymer is disclosed. The highly sulfonated nylon has greater than about 4.0% weight of aromatic sulfonate incorporated into the polymer structure and an unexpectedly low solid particle content as measured by Flow Vision Particle Analyzer and melt filtration studies. Also disclosed is the process and composition of the highly sulfonated nylon copolymer.

Abstract: The present invention provides an improved process for the recovery of caprolactam from polycaprolactam processing waste. The present process for depolymerizing polycaprolactam waste to form caprolactam comprises the step of: in the absence of added catalyst, contacting the polycaprolactam waste with superheated steam at a temperature of about 250.degree. C. to about 400.degree. C. and at a pressure within the range of about 1.5 atm to about 100 atm and substantially less than the saturated vapor pressure of water at the temperature wherein a caprolactam-containing vapor stream is formed.The formed caprolactam may then be used in the production of engineered resins and fibers.

Abstract: The invention relates to polymerisable double-bond derived polyamides obtainable by reacting the polyamide in an aqueous solution with a compound which contains both a polymerisable double bond and an oxirane ring. These derived polyamides may be processed to provide graft polymers with improved properties.

Abstract: A liquid system for executing the anionic lactam polymerization is proposed, which contains activator as well as catalyst and selectively additives and which is liquid at room temperature and remains stable when stored.

Abstract: The invention relates to a process for the preparation of star-branched polymers by reaction in the melt of a polymer having at least one hetero atom in the chain with a compound having at least three functional groups. Suitable polymers are for instance polyamides, polyesters, polyurethanes, polyoxyalkyls, polyimines and copolymers of these. Functional groups are for instance amine, carboxyl, hydroxyl, isocyanate and imine groups. The process is very fast and requires no special purification. The process enables star-branched polymers to be prepared which are derived from so-called AABB polycondensates.

Abstract: A process is disclosed for preparing a polyamide by polymerizing a diacid and a diamine, aminocarboxylic acid or lactam in the presence of excess of either acid or amine such that the ratio of acid to amine end groups or the ratio of amine end groups to acidend groups in the polymer is at least 2.0:1.0.

Abstract: Disclosed are a method for producing a polyamide resin which comprises the steps of extracting with water a polyamide resin obtained by polymerizing caprolactam in the presence of water; condensing the extracted aqueous solution containing unreacted caprolactam and its low polymerized materials; and polymerizing the condensate by adding an additional amount of caprolactam, the improvement wherein(a) among the low polymerized materials of caprolactam, a cyclic dimer is supplied to a polymerization reactor after subjecting it to ring-opening reaction to give a chain structure material in an amount of 15% by weight or more based on the total amount of the cyclic dimer, or(a') a condensate obtained by condensing said aqueous solution until reaching a water partial pressure of 10 kg/cm.sup.2 G or more and a temperature of 230.degree. C.

Abstract: There are proposed a method and a device for manufacturing polyamides, in which polyamide granulate manufactured by polycondensation in the molten mass is after-condensed in the solid phase, being heated. The polyamide granulate is heated in one step to a first temperature of between 70.degree. C. and 150.degree. C., and held for a predetermined period of time at this temperature, and then, in a second step, is heated to a second higher temperature, however lying beneath the melting point, and is after-condensed at this temperature, until the desired average degree of polycondensation is achieved.

Abstract: An acrylic/lactam monomer based polymeric resin is provided which has excellent weatherability, outstanding transparency and optical clarity, improved heath and solvent resistance, as well as improved impact strength. The acrylic/lactam monomer based polymeric resin is formulated by the catalytic activation at ambient temperature of a polymerization syrup which contains from about 300 to about 2970 parts by volume of an acrylic monomer, from about 30 to about 2700 parts by volume of a lactam monomer, from about 0.3 parts to about 40 parts by volume of a mercaptan chain transfer agent and from about 0.3 to about 40 parts by volume of a crosslinking agent capable of crosslinking the acrylic monomer and the lactam monomer. To prevent further polymerization of the polymeric constituents of the polymerization syrup, as well as to enhance the shelf life of the polymerization syrup, an effective amount of a polymerization inhibitor and an ultraviolet light stabilizer are incorporated into the polymerization syrup.

Abstract: Disclosed herein are cyclic oligomers comprising substituted or unsubstituted m-phenylene isophthalamide, complexes of these oligomers with selected metal salts, novel methods for their preparation, and polymerization of the cyclic oligomers to linear aramids. The aramids are useful, for example, as fibers for fire resistant clothing. Amino-finctional cyclic oligomers may be reacted with polyfunctional acyl halides to produce polyamides.

Abstract: A liquid system for executing the anionic lactam polymerization is proposed, which contains activators as well as catalysts and selectively additives and which is liquid at room temperature and remains stable when stored.

Abstract: Branched polyamides are prepared by mixingA) from 10 to 99.7% by weight of a melt of a polyamide prepolymer having a viscosity number of from 40 to 90 ml/g withB) from 0.3 to 6% by weight of a polybasic carboxylic acid, where the number n of the free carboxylic acid groups is 3.ltoreq.n.ltoreq.10, and alsoC) from 0 to 80% by weight of further additives and processing aids,where the percentages by weight of the components A) to C) add up to 100%, and subsequently further condensing the mixture in the solid phase.

Abstract: A process for the activated anionic lactam polymerization is proposed, wherein a liquid system is employed, which simultaneously contains activator and anionic catalyst for the polymerization of the lactam.

Abstract: A continuous process for activated anionic lactam polymerization is proposed, wherein a liquid system is employed, which simultaneously contains activator and anionic catalyst for the polymerization of lactam.

Abstract: A method for the anionic polymerization of a lactam which produces an nylon having a surface resistivity of between about 10.sup.6 to about 10.sup.12 .OMEGA./.quadrature.. Miscible antistatic agents are mixed with the lactam and the moisture concentration in the lactam is adjusted to about 0.4 wt %. When required to complete the polymerization, the initiator concentration in the lactam is adjusted to about 1 wt %.

Abstract: Claimed is a copolyether amide having a melting point in the range of 180.degree. to 260.degree. C., incorporating at least 10 wt. % and not more than 30 wt. % of ethylene oxide groups, and composed of 30 to 60 wt. % of polyamide segments and 70 to 40 wt. % of segments derived from a (cyclo)aliphatic or aromatic dicarboxylic acid or a dimeric fatty acid and a polyoxyalkylene diamine derived from a polyoxyalkylene group having a molecular weight of 600 to 6000 and an atomic ratio of carbon to oxygen of 2.0 to 4.3. Also claimed is a non-porous, waterproof film having a water vapour permeability of at least 1000 g/m.sup.2 day determined at 30.degree. C. and 50% RH in accordance with ASTM E96-66 which is based on a the use of these films in rainwear, shoes, tents, chairs, as mattress covers and understating, for medical purpose garments, and for the manufacture of dressings.

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

Abstract: This invention relates to a coprecipitated binder composition used for the compression of pharmaceutically and agriculturally active components to provide a non-friable pill or tablet of increased hardness with remarkably improved rate of dissolution and improved stability in aqueous solution. The invention also relates to the process for preparing the binder and to its incorporation in a formulation with the active ingredient.

Abstract: Thermoplastic molding materials containA) from 5 to 94% by weight of a partly aromatic, semicrystalline copolyamide composed essentially 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 5 to 94% by weight of an ASA or ABS or SAN polymer or of a C.sub.1 -C.sub.18 -alkyl ester of (meth)acrylic acid or of a mixture thereof,C) from 1 to 30% by weight of an adhesion promoter which contains from 0.