Abstract: A method for delaying curing rate of a curable resin composition comprising a polyfunctional cyanate ester compound or mixture of a polyfunctional cyanate ester compound and a polyfunctional maleimide compound, characterized in that a specific benzene sulfonic acid is added to said composition is disclosed.

Abstract: Methods of making modified polyimide/polyimide-amide foams having selected compressive resistance and density characteristics and the resulting compositions. An N-substituted aliphatic imide is prepared by reacting a suitable aromatic dianhydride with a suitable oxoimine. Within the mole ratio range of oxoimine to dianhydride of about 0.5:1 to about 0.05:1 the compressive resistance of the final foam can be selected in accordance with the intended end use of the foam. Density and compressive resistance varies inversely with the oxoimine quantity in the ratio, being greatest with the 0.5:1 ratio and lowest with the 0.05:1 ratio. A polyimide forming material is prepared by dissolving the N-substituted aliphatic imide in an esterifying solvent, then adding a suitable aromatic diamine. This material is dried to a powder or film. A foam is produced by heating the mateial to reaction temperature for a period sufficient to produce a stable foam.

Abstract: Novel amorphous copolyamides are provided which are the product of reaction of (A) a lactam, (B) a bisimidazoline, and (C) a dicarboxylic acid, wherein the proportions of reactants based on 100 mole percent are from about 43 to about 82 mole percent of lactam (A) and the remaining 18 to 57 mole percent divided between said (B) and said (C) in substantially equimolar proportions.The copolyamides are characterized by better resistance to elevated temperatures than 100 percent polycaprolactam polyamides but at the same time are easily molded because of their amorphous character.

Abstract: Novel polyamides are prepared for itaconic acid, other diacids and diamines. These polyamides are useful as molded objects, fibers, films, laminates and coatings.

Abstract: Polyamides from lactams are prepared by the reaction of an initiator compound, a liquid hydroxy containing nitrile copolymer and a lactam using as a catalyst a minor amount of a lactam anionic polymerization catalyst. The resulting polyamides exhibit high impact strength and improved dimensional stability or reduced sensitivity to dimensional change upon exposure to a high humidity environment.

Abstract: This invention relates to a new process for preparing a copolyamide comprising polymerizing an alpha, beta-unsaturated nitrile and water with a molar excess of a lactam. In one embodiment, acrylonitrile, water and caprolactam are polymerized to form a nylon-3,6.

Abstract: A high temperature and flame resistant closed cell polyimide foam material and methods of making the foam. An aromatic tetracarboxylic acid dianhydride is reacted with an oxomine to produce an N-substituted imide, which is then esterfied with a suitable alcohol. The resulting liquid is dried and the dry residue is reduced to a uniform powder having particles with diameters generally in the 0.5 to 10 mm. range. The powder is preferably further dried, either before or after final size reduction, in a moderate vacuum at moderate temperature to remove any excess residual alcohol. The powder spontaneously expands to form a closed cell foam when heated to a temperature in the range of about 90.degree. to 150.degree. C. for a suitable period. When the powder is expanded in a closed mold, a well consolidated, uniform, closed cell foam product results. When expanded in an unrestricted manner, closed cell "macroballoons" having average diameters between about 0.4 and 15 mm. result.

Abstract: This invention relates to a new process for preparing a copolyamide comprising polymerizing an alpha, beta-unsaturated nitrile and water with a molar excess of a lactam. In one embodiment, acrylonitrile, water and caprolactam are polymerized to form a nylon-3,6.

Abstract: Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. and a lower temperature activator containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170.degree. and 175.degree. C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10.degree., each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to the mixing zone by the tube systems and gear pumps. The products formed crumble on being heated to a temperature of approximately 220.degree. C.

Abstract: Nylon compositions are prepared by anionic polymerization of at least 75% of a lactam with up to about 25% of an epoxy component in the presence of a basic catalyst and a promoter that can be used in lactam polymerization wherein, in a preferred embodiment, the epoxy component is a modified epoxy resin containing physical property enhancing constituents. The nylon compositions are prepared by mixing a fraction of a lactam with the epoxy component and the promotor to form liquid mixture A, mixing remaining lactam with the catalyst to form liquid mixture B, mixing liquid mixtures A and B in the ratio ranging from 1/1 to 4/1 to form liquid mixture C, injecting liquid mixture C into a mold maintained at a temperature of about 100.degree. to 200.degree. C. wherein a chemical reaction takes place whereby the liquid is converted to a solidified mass in less than about 2 minutes, and removing the nylon composition in the form of a molded object.

Abstract: This invention is a transparent alcohol resistant, hot water resistant, thermoplastically formable copolymer of (A) 80.4 to 88.8 weight percent epsilon-caprolactam and the remaining (B) 11.2 to 19.6 weight percent of substantially equimolar portions of a moiety derived from (1) a diamine or diisocyanate and (2) a diacid or (c) 11.2 to 19.6 weight percent para amino benzoic acid.

Abstract: What are disclosed are a polyamide polymer and its use as a melt adhesive for adhering textiles, said polymer having a melt viscosity, measured at 220.degree. C., of 5-150 Pas and being the reaction product of approximately equivalent amounts of an acid component and a basic component, said acid component comprising(a) (1) a dimerized fatty acid having a content of 70-100 percent by weight of dimeric fatty acid and, optionally,(a) (2) a monocarboxylic acid, as a molecular weight regulator, having up to 22 carbon atoms, which monocarboxylic acid may be present in an amount up to 50 equivalent percent of the total carboxy groups of the mixture (a) (1) and (a) (2);(b) at least one aliphatic straight chain co-dicarboxylic acid having 6 to 13 carbon atoms, wherein the ratio of carboxylic acid according to (a) (1) and (a) (2) to carboxylic acid according to (b) is from 0.

Abstract: Methods of making modified polyimide/polyimide-amide foams and the resulting compositions. An N-substituted aliphatic imide is prepared by reacting a suitable aromatic dianhydride with a suitable oxoimine. A polyimide forming material is prepared by dissolving the N-substituted aliphatic imide in an esterifying solvent, then adding a suitable aromatic diamine. This material is dried to a powder or film. A foam is produced by heating the material to reaction temperature for a period sufficient to produce a stable foam. The material melts, then spontaneously expands into a foam which becomes self supporting and cures to a resilient flexible foam. Depending upon heating conditions, a polyimide, polyimide-amide or mixture thereof may be produced, resulting in foams having varying physical properties.

Abstract: Molded articles of polymerized lactams are prepared by pumping of a catalyst containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. and a lower temperature activator containing partial lactam melt at a temperature of .+-.1.degree. C. of a temperature in the range of 160.degree. C. to 170.degree. C. to which activator addition is delayed relative to catalyst addition, with separate gear pumps to a mixing zone maintained between 170.degree. and 175.degree. C., the pumps connected to the mixing zone by straight feed tubes positioned at an angle of inclination to the horizontal of a maximum of 10.degree., each feed tube having a volume of at least one-third greater than the pump to which it is connected and form the mixing zone into a mold. At least part of the gases released are returned to the mixing zone by the tube systems and gear pumps. Apparatus to carry out the method is also provided.

Abstract: Non-crosslinking, water-soluble polyamines which can be obtained by reacting(A) basic polyureas which have been prepared by condensation of ureas with polyamines containing at least three amino groups, of which at least one is a tertiary amino group, or with mixtures of these polyamines with aliphatic, araliphatic, cycloaliphatic or heterocyclic polyamines containing two primary or two secondary amino groups or one primary or one secondary amino group, and optionally with .omega.-aminocarboxylic acids containing at least three carbon atoms, or lactams thereof,(B) polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.

Abstract: Hardenable mixtures which contain a polyepoxide compound with, on average, more than one epoxide group in the molecule, and a hardener of the formula I ##STR1## The symbol n is an integer from 3 to 5. The methylene carbon atoms can be substituted by one or two methyl or ethyl groups.The hardenable mixtures can be used, for example, in the fields of the protection of surfaces or of adhesives technology.

Abstract: Poly(.epsilon.-caprolactam) is prepared with less than 3 percent water-extractable material by carrying out the polymerization reaction in a vessel, the interior surfaces of which are coated with an inert adherent coating of an organic polymer.

Abstract: A mixture for the preparation of novel crosslinked nitrogen-containing polyadducts, which comprises(a) an N-cyanolactam of the formula I or II ##STR1## and (b) a monomeric or oligomeric organic compound having at least 2 C atoms and at least 2 amino groups or at least 1 amino group and 1 hydroxyl group.The curable mixtures of components (a) and (b) and, if desired, a monoamino compound are suitable for use as casting resins or adhesives, or for the preparation of foams and coatings.The symbols are each as defined in claim 1.

Abstract: Extremely rapid ambient curing of polyepoxide resins and mixtures of polyepoxide resins and polyacrylate esters is achieved by use of a curing system composed of at least one polymercaptan and at least one catalytic co-curing agent which is the condensation product of:(a) aliphatic amine or substituted aliphatic amine containing at least one primary aliphatic amine group where the aliphatic moiety is ethylene or greater with(b) at least one amino acid, its corresponding lactam or other amide forming derivative.Optionally, known Lewis Base catalysts for the epoxy/mercaptan reaction, such as tertiary amines, may also be used.

Abstract: Anionic copolymers of lactams and aliphatic polycarbonates having urethane and carboxylic acid ester groups, preferably having recurring structural units of the formula:--NH--CO--O--Y--O--CO--(CR.sub.2).sub.n --whereinR represents hydrogen or C.sub.1 -C.sub.4 -alkyl;n represents an integer of from 2 to 13;Y represents the residue of an alcohol of the following formula:HO--X--OH,whereinX represents an open-chain, cyclic or mixed open-chain-cyclic alkylene radical having from 2 to 12 carbon atoms which is optionally substituted by C.sub.1 -C.sub.4 -alkyl and optionally interrupted by from 1 to 3 oxygen atoms, or a polyethylene glycol having a molecular weight up to 10,000 or an alkoxylation product of bifunctional phenols.

Abstract: Compositions are described, which are blow-moldable into shaped articles, comprising a reaction product between polycaprolactam, aminoalkyltrialkoxysilane and a catalytic amount of water. The compositions have a melt index of about 2.25 g/10 min. or below and are substantially free of trialkoxysilane groups. Preferred compositions also contain ethylene/vinyl acetate copolymer as an impact modifier to increase the impact strength of blow-molded articles made therefrom, such as bottles.

Abstract: The method for preparing polydodecanamide or copolymers based thereon according to the present invention involves melting of .omega.-dodecalactam or a mixture thereof with amide-forming monomers and polymerization of the resulting melt at a temperature ranging from 180.degree. to 320.degree. C. in the presence of a catalyst and a molecular-mass regulator. According to the invention, prior to polymerization the resulting melt is filtered through a filtering bed comprising solid oxidized particles of .omega.-dodecalactam with an elemental content of oxygen of from 10 to 24% by mass.

Abstract: A mixture for the preparation of novel cross-linked nitrogen-containing polyadducts, which contains(a) a N-cyanolactam of the formula I or II ##STR1## and (b) a monomeric or oligomeric organic compound having not less than 2 C atoms and not less than 2 hydroxyl groups.The mixture, with or without addition of a monohydroxy compound, can be used as a casting resin or adhesive, or for the production of foams or coatings.The symbols in the formula are all as defined in claim 1.

Abstract: .epsilon.-Caprolactam is melt polymerized in the presence of water and from about 0.01 mole percent to less than about 0.6 mole percent of an amine boiling at a temperature greater than 245.degree. C. An amine may be a primary or secondary amine wherein the NH has attached thereto, for example alkyl radicals, cycloalkyl radicals, and the like. The resultant polymer has a methanol extractable content of 3 weight percent or less.

Abstract: A composition useful as a catalyst in solution polymerization comprises (1) a barium, calcium and/or strontium alcoholate, (2) an organoaluminum compound and (3) an organomagnesium compound. (2) and (3) may be used as a complex with (1). The compositions can be used to polymerize ethylenically unsaturated monomers like butadiene, butadiene and styrene, and isoprene and heterocyclic monomers like oxiranes, thiiranes, siloxanes, thiatanes and lactams. The catalyst composition can produce polybutadienes and butadiene-styrene copolymers having a trans-1,4 content as high as 90%. The non-terminating features of the polymerization of this invention permit the preparation of functionally terminated butadiene based polymers and block polymers containing sufficient amounts of trans-1,4 butadiene units to crystallize.

Abstract: A process for the continuous preparation of polycaprolactam, which comprises polymerizing .epsilon.-caprolactam in a vertical tubular reactor through which the .epsilon.-caprolactam flows downward, wherein the .epsilon.-caprolactam is partially polymerized, at a nylon-forming temperature, in a mechanically mixed zone, the reaction mixture is circulated through a heat exchange zone in the lower part of the mechanically mixed reaction zone, and is polymerized further, in additional heat exchange zones, until the desired degree of polymerization is reached, and poly-.epsilon.-caprolactam is then discharged as a melt, and an apparatus for carrying out the process.

Abstract: Polymerable organic compounds and an epoxide compound are emulsified with aqueous alkali metal silicate solutions then polymerized with a catalyst such as a peroxide type catalyst thereby producing an alkali metal silicate organic plastic which may be used as an adhesive, as molding powder or reacted with an organic diisocyanide to produce polyurethane silicate resins and foams.

Abstract: Non-crosslinking, water-soluble polyamines which can be obtained by reacting(A) basic polyureas which have been prepared by condensation of ureas with polyamines containing at least three amino groups, of which at least one is a tertiary amino group, or with mixtures of these polyamines with aliphatic, araliphatic, cycloaliphatic or heterocyclic polyamines containing two primary or two secondary amino groups or one primary or one secondary amino group, and optionally with .omega.-aminocarboxylic acids containing at least three carbon atoms, or lactams thereof,(B) polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.

Abstract: Polyamide materials for the construction of protheses and surgical sundries are made biocompatible by inducing a superficial hydrolysis by treating such materials, either raw or in the form of shaped articles, with a normal multiple solution of hydrogen chloride. Thrice normal or fourfold normal solutions are preferred and the treatment time being a function of the temperature. At human body temperature (37.degree. C.) a treatment time from 30 to 60 minutes will do.

Abstract: Polyamide powder coating compositions for the coating of metals at high temperatures are obtained by the precipitation method from polyamides having at least 10 aliphatically bound carbon atoms per carbonamide group, copolyamides having at least 70% of these polyamides and mixtures of homopolyamides and copolyamides having at least 70% of these polyamides.A. For the preparation of powder coating compositions useful in the fluidized bed coating method the polyamides with 10 or more carbon atoms and having a relative viscosity between 1.4 and 1.8 are added to at least twice the amount by weight of ethanol and while the mixture is being mechanically mixed in a closed vessel is converted into a solution at temperatures between 130.degree. and 150.degree. C. This solution is adjusted to a precipitation temperature of between 100.degree. and 125.degree. C. while avoiding the formation of local sub-cooling and is agitated under an inert gas atmosphere to suppress boiling.

Abstract: A process for the production of polyamide-6 or corresponding copolyamides by hydrolytic polymerization wherein the low molecular weight secondary reaction products and the unreacted .epsilon.-caprolactam are separated off from the polyamide melt and directly condensed on the .epsilon.-caprolactam melt to be polymerized.

Abstract: Compounds typified by N,N'-polyoxyalkylene bis (pyrrolidinone-3-carboxylic acid) are useful as epoxy curing accelerators. Salts thereof, including alkali metal salts, are curing agents for isocyanurate foams.

Abstract: Alkali metal aminoalkanoate is prepared by contacting in the presence of an alkali metal carboxylate a reaction mixture in which there is at least one alkali metal hydroxide, at least one lactam, and water. Arylene sulfide polymer is prepared by contacting at polymerization conditions a reaction mixture that contains at least one alkali metal aminoalkanoate prepared as described above; at least one polyhalo-substituted aromatic compound; at least one organic amide as solvent and H.sub.2 S. In an embodiment of the polymerization the organic amide used as solvent can be the same as the lactam from which the alkali metal aminoalkanoate was produced.

Abstract: A method for producing flame resistant synthetic polyamides, suitable for inning is described, wherein melamine and isocyanuric acid are reacted in an aqueous environment at the melamine isocyanurate formation temperature. An aqueous suspension of melamine isocyanurate is obtained having a maximum granule size not exceeding 2 microns, substantially free from agglomerates. The suspension is admixed with the monomeric material and the whole is submitted to polymerization. The invention provides a successful method for obtaining flame-resisting polyamide fibers and yarns owing to the presence therein of the melamine isocyanurate additive.

Abstract: Compositions are described, which are blow-moldable into shaped articles, comprising a reaction product between polycaprolactam, aminoalkyltrialkoxysilane and a catalytic amount of water. The compositions have a melt index of about 2.25 g/10 min. or below and are substantially free of trialkoxysilane groups. Preferred compositions also contain ethylene/vinyl acetate copolymer as an impact modifier to increase the impact strength of blow-molded articles made therefrom, such as bottles.

Abstract: A two-stage hydrolysis process for polymerizing epsilon-caprolactam is disclosed comprising a first stage from a temperature of about 180.degree. C.-260.degree. C., a pressure of 20 to 150 psig, for a period of about 0.5 to 4 hours, then before equilibrium conditions are reached a second stage at a temperature of about 200.degree. C.-260.degree. C., a pressure of about 100-900 Torr for a period of about 2 to 15 hours, while continuously removing most of the water so that water is removed both during hydrolyzation and during the subsequent polycondensation, whereby the cyclic dimer content of the shaped polymer article is below 0.2 percent by weight.

Abstract: A method is described for the anionic polymerization and copolymerization of .omega.-aminoacid lactams. This end is attained at elevated temperatures in the presence of a polymerization initiator of the formulaMeZX.sub.m L.sub.nwherein Me is an alkali metal, Z is boron or aluminum, X is an alkoxy group and L is an organic residue derived from a lactam and being of the formula ##STR1## wherein a is an integer in the range 3-11, m is an integer in the range of 0-3, (m+n) is 4 and n is (4-m).

Abstract: Provided are polyamides having properties which make them useful as adhesives, sizing agents, paper strength enhancers and as resins. These polyamides are prepared by heating an alpha-(N,N-disubstituted amino)-E-caprolactam, alone or in combination with one or more comonomers, in the presence of an anionic polymerization catalyst, and are characterized by a repeating unit reprsented by the formula ##STR1## wherein R and R' are each a lower alkyl group or a cyclic amine residue, and also having a relative viscosity of at leasrt 1.5.

Abstract: A highly rigid poly-.epsilon.-caproamide composition containing about 50 to 5000 ppm of barium combined with the poly-.epsilon.-caproamide, and having a .gamma.-type crystal ratio of about 0.3 to 0.7 is disclosed. The polyamide has improved rigidity without loss of other advantageous mechanical properties of poly-.epsilon.-caprolactam. By addition of an aluminum compound, the rigidity of the composition can be further improved. A bisamide compound may be added to provide excellent mold release without harming the mechanical properties of the composition.

Abstract: A copolymer having peroxy bonds in the molecule thereof which is obtained by copolymerizing an diacyl type polymeric peroxide having ester bonds therein with one or more monomers having double bonds therein, may have a broad range of average molecular weight and a lot of peroxy bonds therein, and it may be used as an useful polymerization initiator in producing a block copolymer.

Abstract: A polymer containing repeating units of the formula: ##STR1## wherein R.sub.1 and R.sub.2 are independently hydrogen, alkyl, aryl, aralkyl, substituted alkyl, substituted aryl, substituted aralkyl, R.sub.3 is hydrogen, alkyl or --CH.sub.2).sub.n COOR.sub.8 where n is an integer of 0 to 10, R.sub.6 is OR or NR.sub.4 R.sub.5, wherein R and R.sub.8 are independently hydrogen or a group derived from a compound containing esterifiable hydroxyl groups, R.sub.4 and R.sub.5 are independently alkyl, aryl, aralkyl, substituted alkyl, substituted aryl, substituted aralkyl or together comprise an alkylene group.

Abstract: A process for removing volatile constituents which are evolved from plastic melts when extruding the latter and are drawn off together with the surrounding air. The volatile constituents are drawn off immediately as they are evolved by the plastic melt and the air containing such volatile constituents is heated immediately after entering the suction orifice, and an apparatus for carrying out this process.

Abstract: Disclosed is a polyamide multifilament yarn comprising a plurality of polycapramide multifilaments and having a high softness, a mild touch, a level-dyeing property and an excellent colorfastness to washing and laundering. The individual filaments in this yarn are characterized by a birefringence of 0.045 or more, a denier of 0.8 or less and a ratio of the X-ray diffraction intensity I.sub.23 at an angle (2.theta.) of 23.2 degrees to the X-ray diffraction intensity I.sub.21 at a peak formed at an angle (2.theta.) of approximately 21 degrees which ranges from 0.50 to 1.00. A process for producing the above-mentioned polyamide yarn is also disclosed.

Abstract: Acetylene end-capped polyimide oligomers are prepared by a process including the following sequential steps:1. Preparing an alkanol or ether solution containing substantially 1 molar equivalent of a dialkyl ester of an aromatic tetracarboxylic acid,2. Adding substantially 0.5 to 0.8 molar equivalent of an aromatic diamine to the solution of (1) to form a reaction product between the diacid and the diamine,3. Adding an aminoarylacetylene to the solution of (2) in a quantity sufficient to provide amine groups equivalent to the free carboxylic acid groups present in the product of (2).4. Heating the solution of (3) to vaporize the solvent therefrom, and5. Heating the product of (4) to convert the carboxylic acid groups, the ester groups, and the amino groups thereof to imide groups.The temperature in steps (2) and (3) is maintained below about 50.degree. C. The temperature in steps (4) and (5) is maintained below about 210.degree. C.

Abstract: Polyphosphazene polymers are prepared which contain repeating units represented by the formulas: ##STR1## wherein X is represented by: ##STR2## wherein Y is selected from the group consisting of ##STR3## and --SO.sub.2 -- and p=0 or 1; when p=0, R.sub.1 and R.sub.2 are independently selected from a group consisting of substituted or unsubstituted aliphatic, aryl, araryl, and alkylaryl radicals or R.sub.1 and R.sub.2 can form a cyclic amide containing radical wherein R.sub.1 and R.sub.2 taken together are selected from a group consisting of --CH.sub.2).sub.n where n=2 to 12, wherein R.sub.3 is a lower alkyl radical or hydrogen; and when p=1, R.sub.1 and R.sub.2 taken together form a linkage in a cyclic imide containing radical selected from a group consisting of --CH.sub.2).sub.n, where n'=2 or 3 and ##STR4## where R.sub.3 is as defined above, R.sub.

Abstract: A process to synthesize poly (ether-ester-amide) sequence copolycondensates by the reaction in a molten condition between a dicarboxylic polyamide, in which the carboxylic functions are located at the chain-ends, and a polyoxyalkoylene with hydroxylated chain-ends, in the presence of a catalyst.This reaction is performed continuously in a thin-film reaction space through which the reaction mixture passes continuously under turbulent flow conditions.This process, which involves much shorter reaction times, produces sequence copolycondensates with better mechanical properties than corresponding substances obtained by batch processes.

Abstract: Method for preparing and using thermoplastic polyether ester amides with units of the starting components randomly distributed in the polymer chain. A mixture of:I. one or more polyamide forming compounds from the group of the omega-aminocarboxylic acids and/or lactams having at least 10 carbon atoms;II. an alpha, omega-dihydroxy-(polytetrahydrofuran) having an average degree of polymerization of between about 2 and 42 or a molecular weight of between 160 and 3,000; andIII. at least one organic dicarboxylic acid is heated in a weight ratio of I to (II+III) of between 30:7 and 98:2. In (II+III) the hydroxy and carboxy groups are present in equivalent amounts. The heating takes place in the presence of 2-30% by weight of water, based on the polyamide-forming compounds of component I, under the internal pressure attained in a closed container at temperatures of between 230.degree. and 300.degree. C. Water is removed as steam and after removal of the water, the product is further treated at 250.degree.-280.

Abstract: An improved process for the continuous polymerization of .epsilon.-caprolactam in the presence of water as initiator in a vertical downward-flow tubular reactor, in which the .epsilon.-caprolactam is partially polymerized at elevated temperature in a first, mechanically agitated reaction zone and is further polymerized in further reaction zones to the desired degree of polymerization. Poly-.epsilon.-caprolactam is discharged in the form of a melt. The polymerization is carried out at a gauge pressure of from 0.2 to 0.9 bar, constant in all reaction zones. The temperature in the first reaction zone is maintained according to the relationship t.ltoreq.265+43 p .degree.C., where p is the numerical value of the gauge pressure in bars which relationship is subject to the condition that the temperature be within the range of 260.degree. to 295.degree. C.

Abstract: Processes for the production of polyamides by polymerizing lactams in the presence of a catalyst and anisocyanatoallophanate as activator.

Abstract: A catalyzed process for the preparation of monomeric and/or polymeric compounds such as esters, polyesters, ester-amides, and polyester-polyamides which result from the reaction of an imide and an alcohol in the presence of a Group IA, IIA, IIB and/or IIIA metal or metal compound, imide-alcohol condensation catalyst.