Abstract: A solid-state polymerization process for increasing the molecular weight of a polymer such that the n value is at least 200 comprising heating within a heating zone at a temperature of at least 200.degree. C. a crystalline polymer corresponding to the structure:[(--A--S--).sub.1-x (--A--S--S--).sub.x ].sub.nwherein A is a divalent substituted or unsubstituted aromatic radical, x is in the range of 0.5 to 0.001 and n is at least 20 wherein the volume of the heating zone not occupied with polymer is either under vacuum or is occupied with an inert gas.

Abstract: A method of stabilizing a poly(arylene ether ketone), which method comprises in one embodiment heating the poly(arylene ether ketone) at a temperature between about 240.degree. C. and about 325.degree. C. for a period of between about 0.5 and about 24 hours, prior to any melt-processing of the poly(arylene ether ketone) and in another embodiment hydrothermally treating the poly(arylene ether ketone) by heating it to a temperature of at least 160.degree. C. while contacting it with water.

Abstract: The present invention relates to a method for hot curing thermosetting resins and vulcanizable elastomers, based on the use of perfluoropolyethers in the liquid state as heat transfer media.

Abstract: Catalyst residues are reduced in linear alternating polymers of carbon monoxide and at least one ethylenically unsaturated hydrocarbon produced in the presence of a Group VIII transition metal catalyst by contacting the linear alternating polymer with a dithiocarbamate compound in a non-gaseous reaction environment in an oxygenated organic reaction diluent.

Abstract: A process for producing a stretched molded article of a conjugated polymer, hich comprises subjecting a polymer precursor having a repeating unit represented by the general formula (I) ##STR1## (wherein R.sub.1 is a group which forms a C--C conjugated system together with a vinylene group which is formed upon the dehydrogenation of the >CH--Ch.sub.2 -- group; and R.sub.2 is a group which is to be eliminated from the alpha-position carbon of the >CH--CH.sub.2 -- group simultaneously with the elimination of one of the hydrogen atoms bonding to the beta-position carbon of the >CH--Ch.sub.2 -- group) to stretching in the swelling state and then subjecting the stretched precursor polymer to elimination of the R.sub.2 group, and a conductive composition of the stretched molded article of the conjugated polymer, comprising the comjugated polymer and a dopant as essential components.

Abstract: The specification discloses a readily de-waterable modified rubber concentrate and method for forming same from a process including the preparation of a latex emulsion of the modified rubber concentrate, insuring that the emulsified modified rubber concentrate has a rubber content of from about 57 to about 88% by weight and freeze coagulating the modified rubber concentrate from the emulsion.

Abstract: The invention relates to a copolyamide for application in films with improved barrier properties. The copolyamide containing tetramethyleneadipamide and tetramethylene-isophtalamide in a ratio between 9:1 and 1:9 and a relative viscosity of at least 2.0, and a process for the production of the copolyamide. Preferably the copolyamide contains a small amount of a compound that induces the formation of networks between the polyamide chains.

Abstract: A process for producing a low-particle polycarbonate resin molding material suitable for use as molding material for optical materials is disclosed, which comprises directly supplying a polycarbonate resin wet powder having a water content of from 0.5 to 10.0% by weight and an organic solvent content of from 0.01 to 5.0% by weight, said wet powder, when dried, having a weight average particle diameter of from 5 to 60 mesh, to a vented extruder and extruding the wet powder while venting to obtain pellets containing not more than 20 ppm of a residual halogenated hydrocarbon. The molding material has a greatly decreased solvent content while being freed from a particle content increase.

Abstract: Thermotropic, fully aromatic polyesters based on p-hydroxybenzoic acid, aromatic dicarboxylic acid and diphenol in which the dicarboxylic acid groups consist at least in part of 3,3'-diphenyldicarboxylic acid groups have excellent mechanical properties, in particular excellent elongation at break.

Abstract: Polymer compositions comprising polyphenylene ethers free from polystyrenes are extruded with vacuum venting at 300.degree. C. or above in the presence of water. This extrusion operation reduces the content of volatile impurities, including those with an undesirable odor.

Abstract: A resin-molding tablet for use in resin-molding semiconductor devices has a tablet body formed of powdered or particulate resin. The particles of the resin are compacted such as to form voids between adjacent particles. At least the outer peripheral region of the tablet is fused such that the resin particles are welded together to form a continuous layer of fine and impervious structure substantially free of open pores. The internal air trapped in the voids of the tablet is drawn and removed before the tablet is fused so that the tablet is substantially free of air. The tablet is produced by placing a particulate or powdered resin material in a vacuum vessel so as to allow the internal air in the resin material to be drawn outside, and then applying pressure and heat to the resin material so that at least the peripheral region of the mass of the particulate resin is fused to weld together.

Abstract: The invention relates to the use of a fraction of hardened particles of an elastomer material of limited particle sizes between 0.1 and 1 mm, preferably between 0.3 and 0.7 mm. The order of magnitude of the admixture to every 100 parts of unhardened elastomer material lies at 5 to 60 parts, preferably 20 to 40 parts. The admixture of the particles to the elastomer material is effected before the elastomer material hardens and is done to produce a defined, non-smooth surface in end products made of elastomers.

Abstract: Sintered polybenzimidazole articles are obtained by compacting a particulate, dried polybenzimidazole resin under a pressure of 2,000 to 10,000 psi in a mold, heating the formed article to a temperature in the range of 825.degree. to 950.degree. F. for at least four hours, cooling the polybenzimidazole article to below 800.degree. F. while maintaining the article under a pressure of 2,000 to 10,000 psi, and thereafter heating the constrained formed polybenzimidazole article to a temperature in the range of 825.degree. to 950.degree. F. for at least one hour.

Abstract: The invention relates to the purification of polymers, particularly resorbable polyesters, using shear fields produced mechanically or by fluid dynamics.

Abstract: A method and apparatus for devolatilizing high viscosity polymer solutions are provided wherein high viscosity polymer solutions are heated along a short zone of indirect heat exchange. The residence time within the zone of indirect heat exchange ranges from approximately 5 seconds to 120 seconds.

Abstract: A process for producing a 4-methylpentene-1 copolymer comprising copolymerizing 4-methylpentene-1 with other .alpha.-olefin in a hydrocarbon solvent in the presence of a Ziegler-Natta catalyst and a resin composition containing the 4-methylpentene-1 copolymer are disclosed. The copolymerization comprises a first stage in which (A) a homopolymer or random copolymer of 4-methylpentene-1 having an .alpha.-olefin content of not more than 3 mol % and an intrinsic viscosity of at least 2.5 dl/g is prepared and a second stage in which (B) a random copolymer having an .alpha.-olefin content higher than that of the polymer (A) and no higher than 9 mol % and an intrinsic viscosity of at least 2.5 dl/g is prepared, and the produced copolymer insoluble in the solvent is separated to recover a 4-methylpentene-1 copolymer containing from 5 to 80% by weight of the polymer (A). The process produces a solvent-insoluble copolymer in an increased yield without impairing transparency of the copolymer.

Abstract: A process for the preparation of a polyphenylene layer which comprises the steps of treating a copolycyclohexa-3,4-diene under first conditions to aromatize a portion of the aromatic rings and then under second conditions to aromatize the residual cyclohexadiene rings from the first treatment.

Abstract: An oil-soluble additive for lubricating oil applications is provided by the formation of an adduct of thiocyanogen halide and polyalkene, removal of the hydrogen halide from said adduct and thermal rearrangement of the product to provide a polyalkenyl isothiocyanate which can be subsequently derivitized to provide a thiocarbamyl moiety containing product having excellent sludge dispersement properties.

Abstract: A process for the preparation of a polymer composition which comprises a polyarylene which process comprises treating a first composition comprising a polycyclohexadiene, a suitable additive and a solvent for the polycyclohexadiene to a suitable heat treatment such that at least a major portion of the cyclohexenylene rings in the polycyclohexadiene are converted into aromatic groups.

Abstract: The homogeneity of highly reactive polycondensates is improved in a process involving batch operations in a reactor, followed by extrusion and then cooling by a coolant to the point of solidification after which the polycondensates are milled and removed. The cooling is carried out with a low-boiling liquified gas.

Abstract: A frozen urethane premix coating material is prepared by mixing together an isocyanate, a hydroxy terminated aliphatic polyol, and an organic solvent in an amount of at least 75 percent by weight of the total weight of the premix, and then freezing the mixture. The storage life of the mixture is several months, after which it is thawed and used as a coating material. In one form, the premix includes 4,4'-diphenyl methane diisocyanate as the isocyanate and a mixture of toluene and methyl ethyl ketone as the solvent.

Abstract: The invention relates to highly filterable polyvinyl polypyrrolidone particles and to the process for improving filterability of standard polyvinyl polypyrrolidone granules, wet cakes and slurries which comprises heating granular polyvinyl polypyrrolidone, containing a minor amount of non-crosslinked and/or unsaturated sites while maintaining between 1 wt. % and 20 wt. % moisture at a temperature of between about 50.degree. C. and about 250.degree. C. under a pressure of from about 5 psig. to about 200 psig. and collecting product having an average particle size distribution between about 40 and 400 mesh, a non-volatile water solubles (NVWS) content less than 2% and a filter flow rate greater than 95.

Abstract: A process for preparing highly viscous polyhexamethyleneadipamide by postpolycondensing the melt of a polymer having a relative viscosity of 2.5-2.7 (measured in a 1% strength solution in 96% strength sulfuric acid) in a twin-screw extruder having degassing zones and closely meshing screws which turn in the same direction. The polymer melt is polycondensed in the extruder by treatment in a plurality of serially arranged zones of alternatingly elevated and reduced pressure, wherein in the zones of elevated pressure, steam superheated to the temperature of the melt is supplied to the melt in an amount of 0.05-0.7 kg/kg of polymer, whereas in the zones of reduced pressure, the input vapor phase and water of condensation are drawn off. The temperature of the melt is raised at a uniform rate over the length of the extruder from 260.degree.-280.degree. C. in the first zone to 280.degree.-310.degree. C. in the last zone.

Abstract: Melt-processible tetrafluoroethylene/perfluoroolefin copolymer granules, and process for their preparation, are disclosed having improved thermal stability, high purity and reduced bubble tendency.

Abstract: Aluminum nitride structures are made by pyrolyzing the condensation products of certain organo-aluminum compounds with certain aromatic diamines, triamines or tetraamines.

Abstract: Provided is a medical material comprising a molded hydrogel obtained by pouring an aqueous solution containing not less than 6 wt. % of a polyvinyl alcohol which has a degree of hydrolysis not less than 97 mole % and average polymerization degree not less than 1,100, into a desired shape of a vessel or mold, freeze-molding the aqueous solution at a temperature lower than -5.degree. C., then partially dehydrating the resulting molded product without thawing it up to a percentage dehydration not less 5 wt. %, and if required, immersing the partially dehydrated, molded product in water to attain a water content thereof in the range of 45 to 95 wt. %.

Abstract: The continuous solution polymerization of an acrylate, particularly methyl methacrylate, is practiced in the presence of a large quantity of solvent by introducing the monomer feed into a continuous loop of recycled solvent and removing the polymerized product therefrom. The polymerization is practiced in a plurality of stages, preferably two stages wherein the bulk of the polymerization is performed in the first stage and the final stage is operated to deplete the initiator and any other polymerization modifiers, thereby forming a crude polymerizate for devolatilization. A product of superior thermal stability and optimum heat distortion temperature is achieved by the addition of some of the comonomer such as methyl acrylate, or ethyl acrylate, etc., to the final stage or stages of the polymerization. Additionally, the product quality is enhanced by addition of a portion of the chain transfer agent, such as n-dodecyl mercaptan, to the final stage or stages of polymerization.

Abstract: This invention relates to a process for preparing melt-processible tetrafluoroethylene perfluoro(alkyl vinyl ether) (TFE/PAVE) copolymer granules having good particle flow characteristics and thermal stability, and to the product of the process.

Abstract: A circulation loop is provided between a point next to the outlet of an amorphous polyalphaolefin polymerization zone and a flash zone, carrying a stream of molten devaporized polymer product.

Abstract: A method for the production of reformed p-vinylphenol polymers which are lightened in color comprising treating a p-vinylphenol polymer under heating at about 150.degree. C. to about 350.degree. C. in the presence of an amine, and if optionally, in the additional presence of an acid compound and/or a reducing agent, and if necessary, in the additional presence of an inert solvent.

Abstract: Disclosed is a continuous treating process of a rubber modified styrenic polymer composition produced by bulk or solution polymerization and containing at least 1% by weight of a rubber component and at least 16% by weight of the total amount of an unreacted monomer and solvent which process comprises treating the polymer composition in two-step volatile component separation apparatuses, each of which comprises a multi-tube preheater and a volatilizer, to remove the unreacted monomer and other volatile components wherein the first treated composition contains 3-15% by weight of the unreacted monomer and solvent.

Abstract: Elastomeric materials such as elastomeric nonwoven webs of elastomeric meltblown fibers, elastomeric films or elastomeric molded materials are attained by forming, e.g., extruding or meltblowing, a polystyrenic poly(ethylenebutylene) thermoplastic block copolymer at elevated temperatures of at least about 290 degrees Centigrade, e.g., from about 290 degrees Centigrade to 345 degrees Centigrade. The resulting products retain good elastic elongation and strength properties. In the case of elastomeric nonwoven webs of elastomeric fibers, other fibers such as cellulosic fibers, e.g., cotton fibers, may be combined with the elastomeric fibers by known methods to provide an elastomeric nonwoven web comprising a blend of the elastomeric fibers with other fibers. Such web or film materials are useful generally in applications utilizing webs or sheets of elastic fabrics or the like, for example, in making composite materials in which an elastic layer of material is bonded to a gatherable web.

Abstract: Propylene-base random copolymer particles suitable for use in the production of pre-foamed particles are obtained by heating starting copolymer particles of ethylene-propylene random copolymer to the crystallization temperature thereof and then quenching them in a medium at a temperature of (the crystallization temperature-30.degree. C.) or lower. Pre-foamed particles produced using the copolymer particles contain large cells are columnar in shape with an average diameter D of 1.7 mm or less and an L/D.gtoreq.1. They can thus provide foamed moldings which are substantially free of shrinkage and have good flexibility.

Abstract: An unusual polybutene-1 polymer blend based on the ability of polybutene-1 to undergo random scission of molecules in a chemical cracking process. Such cracked polymer when blended back with the parent polybutene-1 produces a unique molecular weight distribution which is manifested in a unique and valuable combination of processing behavior and mechanical, optical and thermal properties of film made from the blend. Good hot tack, low heat sealing temperature and high clarity as well as improved processability are simultaneously achieved in these films.

Abstract: Melt-processible tetrafluoroethylene/perfluoroolefin copolymer granules, and process for their preparation, are disclosed having improved thermal stability, high purity and reduced bubble tendency.

Abstract: According to the invention, a method for modifying a polyfumaric acid diester is provided. The method comprises subjecting the polyfumaric acid diester to thermal treatment to thereby obtain a polyfumarate having carboxyl groups. The polyfumaric acid diester is obtained by polymerizing a fumaric acid diester represented by the following general formula of: ##STR1## wherein R represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms or an organic residue having at least one aromatic ring.

Abstract: Unstable backbone links in melt-processible tetrafluoroethylene copolymers can be reduced by subjecting the copolymer to high shear in a twin-screw extruder.

Abstract: A high strength and modulus conjugated polymer film which comprises as its rincipal constitutive unit a conjugated polymer structure represented by the general formula:--R--CH.dbd.CH).sub.nwherein R is an aromatic hydrocarbon group having 6 to 20 carbon atoms which forms a consecutive carbon to carbon conjugated system with vinylene group, and n is an integer of 5 to 50,000, and has a tensile strength of 15 kg/mm.sup.2 or more and an elastic modulus of 350 kg/mm.sup.2 or more, and a highly electroconductive pyrolyzed product thereof.

Abstract: A polyester having an initial accumulation electric charge of not less than 2.9 .mu.c/mm.sup.2 when determined in a melt state according to the method as hereinabove defined and a heat resistance of not more than 0.210 when determined according to the method as hereinabove defined, which comprises at least one magnesium compound and at least one phosphorus compound solubilized therein in amounts as satisfying the following formulas:30.ltoreq.[Mg].ltoreq.400 (1)0.8.ltoreq.Mg/P.ltoreq.3 (2)wherein [Mg] is the content (ppm) of the magnesium compound in terms of magnesium atom to the polyester and Mg/P is the atomic ratio of the magnesium atom in the magnesium compound to the phosphorus atom in the phosphorus compound.

Abstract: Disclosed herein are propylene-base random copolymer particles suitable for use in the production of pre-foamed particles. The copolymer particles are obtained by heating starting copolymer particles to the crystallization temperature thereof and then quenching them in a medium of (the crystallization temperature-30.degree. C.) or lower. Processes for obtaining the copolymer particles are also disclosed. Pre-foamed particles produced using the copolymer particles contain large cells. They can thus provide foamed moldings which are substantially free of shrinkage and have good flexibility.

Abstract: A semisintered polytetrafluoroethylene article which is prepared by heating an unsintered polytetrafluoroethylene article at a temperature of at least the melting point of a sintered polymer, the article having an endothermic curve at a temperature of 345.+-.5.degree. C. on a crystalline melting chart measured with a differential scanning carolimeter and a crystalline conversion of from 0.10 to 0.85 defined by heat of fusion of the unsintered, semisintered and sintered polymer, and the crystallinity of the semisintered article measured by X-ray diffraction being from 80 to 93%. The article is expandable biaxially to afford a porous polytetrafluoroethylene material having an almost unporous surface.

Abstract: The specification discloses a method for freeze coagulating polymeric material in which the freezing surface is coated with a thin film of ice to facilitate separation of the coagulated material from the freezing surface without the need for mechanical scraping.

Abstract: An isotropic semicrystalline morphology of ultra-high-molecular-weight polyethylene and a method of making it. An original powder stock or a partially fused, melt-crystallized stock having a granular memory, is heated to a temperature at which the stock fuses completely to form a homogeneous melt which loses memory of the granular structure of the original stock. The resultant melt is cooled to ambient temperatures under compression to provide a novel homogeneous isotropic semicrystalline morphology. An anisotropic morphology of ultra-high-molecular-weight polyethylene may then be made by solid-state deforming that semicrystalline morphology at a temperature near but below its crystalline melting point at a deformation ratio of about 5 to 8.

Abstract: The invention is a chemical process for complete destruction and safe disposition of hazardous organic chemicals such as Polychlorinated Biphenyl (PCB). The invention also comprises the process for production of an inert polymer formed of essentially equal parts of Carbon and Sulfur, and also comprises the new inert polymer, itself and articles made of the new polymer. This new polymer has many of the properties of refractory materials and is an inert non-inflammable cross-linked polymer that is relatively insoluble in all generally known solvents. In the process of the invention PCB and Sulfur are heated, in an atmosphere of Nitrogen at 500.degree. to 1500.degree. C. Waste gases including sulfur and sulfides are condensed, scrubbed and the sulfur recycled. The solids residue when analyzed by a mass spectrometer contains less than one (1) part per million (1 ppm) of unreacted polychlorinated biphenyl (PCB).

Abstract: The present invention is directed to polymethylmethacrylate bone cement that is premixed and frozen so as to arrest the polymerization reaction at a suitable point. The frozen bone cement is treated by electromagnetic radiation to insure sterility. In use, the bone cement is warmed until it reaches a temperature and consistency suitable for use. The bone cement may be prepackaged in a syringe, or may be molded for use in connection with a particular prosthesis, or may be packaged unitarily with a prosthesis.

Abstract: A method of providing cured latex-based compositions is disclosed which permits in situ curing of latexes disposed in plastic container closures or other heat sensitive receptacles without adverse effect on the closure or receptacle. The method comprises heating a fluid latex composition to gel the latex and effect removal of at least a portion of the water initially contained therein and subjecting the resultant composition to modulated microwave energy to effect curing thereof. Modulation of the microwave energy is achieved by applying same in an intermittent or pulsed fashion. The method is of particular interest for the in situ formation of cured latex-based gaskets in polyalkylene container closures.

Abstract: A trioxane copolymer is manufactured by adding to trioxane and a co-monomer, 0.0001 to 2.0 percent by weight, based on the total weight of the monomers, of one or more sterically hindered phenols, then co-polymerizing the resultant mixture in the presence of a cation-active catalyst, and then treating the resultant copolymer by heating it at a temperature which is higher than the melting point of the copolymer to melt the copolymer and decompose and remove unstable parts of the copolymer.

Abstract: The invention relates to a simplified, economic process for the production of polyamines by the alkaline hydrolysis of compounds containing terminal aromatic and/or aliphatic isocyanate groups (including modified isocyanates or NCO-prepolymers and semi-prepolymers with NCO-contents of from 0.5 to 40% by weight), with strong aqueous bases, direct isolation of the polyamines from the carbamate stage being possible by thermal carbamate decomposition and/or solvent extraction.The invention also relates to the use of the aromatic and/or aliphatic polyamines containing primary NH.sub.2 -groups obtainable by the process according to the invention for the production of polyurethanes, such as optionally cellular polyurethane plastics and polyurethane foams.

Abstract: A process for producing a coagulated latex is disclosed which comprises spraying into a coagulating chamber a suspension liquid or a high polymer latex to disperse as droplets, simultaneously spraying a coagulant into the chamber in the form of gas or mist, introducing into the chamber super-heated steam to heat dispersed droplets of the suspension liquid or the high polymer latex and the coagulant, collecting coagulated particles in a film-like flow of water or an organic solvent flowing downward along side walls and the bottom of the chamber, and recovering the coagulated particles.

Abstract: The invention relates to a simplified, economic process for the production of polyamines by the alkaline hydrolysis of compounds containing terminal aromatic and/or aliphatic isocyanate groups (including modified isocyanates or NCO-prepolymers and semi-prepolymers with NCO-contents of from 0.5 to 40% by weight), with strong aqueous bases, direct isolation of the polyamines from the carbamate stage being possible by thermal carbamate decomposition and/or solvent extraction.The invention also relates to the use of the aromatic and/or aliphatic polyamines containing primary NH.sub.2 -groups obtainable by the process according to the invention for the production of polyurethanes, such as optionally cellular polyurethane plastics and polyurethane foams.