Abstract: By adding a swelling agent which does not dissolve solid polymers to plastics granulates, the morphology is extended without product damage to such as extent that residual constituents can be quickly removed down to a few ppm by diffusive transport and subsequent separation of the swelling agent. The remaining swelling agent is then removed by application of heat.

Abstract: A process for tempering unextracted polycaprolactam is disclosed which results in polycaprolactam having suitable physical and chemical properties for melt extrusion and spinning, without the need for conventional solvent/water extraction and drying of crude granules.

Abstract: High molecular weight polyester resins such as polyethylene terephthalate, are sometimes produced from low molecular weight polyester prepolymers having the same composition by solid state polymerization. The low molecular weight polyester prepolymers which are used in such solid state polymerizations are normally prepared by conventional melt polymerizations and are generally in the form of pellets or chips. It has been unexpectedly found that solid state polymerization rates can be greatly improved by utilizing polyester prepolymers which are in the form of porous pills. By utilizing polyester prepolymers that are in the form of porous pills, higher molecular weights can be achieved after shorter solid state polymerization times.

Abstract: Polyisocyanates containing only trace amounts of free aromatic diisocyanates are recovered by purifying and isolating an isocyanate condensate containing free NCO groups from an impure admixture thereof, said isocyanate condensate impure admixture having been prepared by reacting a stoichiometric excess of an aromatic di- or polyisocyanate with a reactant compound containing at least two functional groups which are reactive with NCO groups, and such purification/isolation entailing extracting unreacted excess di- or polyisocyanate from said impure admixture with an inert gas, e.g., carbon dioxide, in either the liquid or supercritical state.

Abstract: High molecular weight polyester resins such as polyethylene terephthalate, are sometimes produced from low molecular weight polyester prepolymers having the same composition by solid state polymerization. The low molecular weight polyester prepolymers which are used in such solid state polymerizations are normally prepared by conventional melt polymerizations and are generally in the form of pellets or chips. Solid state polymerization rates can be greatly improved by utilizing polyester prepolymers which are in the form of porous pills. By utilizing polyester prepolymers that are in the form of porous pills, higher molecular weights can be achieved after shorter solid state polymerization times.This invention relates to an improved process for solid state polymerizing porous pills which are made by compacting fine fibers of the polyester prepolymer.

Abstract: A process for producing a copoly(arylene sulfide) 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 200, comprising reacting within a reaction zone a mixture of a diiodoaromatic compound and elemental sulfur at a polymer producing temperature wherein the reaction zone contains an oxygen-containing gas flowing at a rate in the range of 0.001 to 0.08 ft3/hr/mol of oxygen per mole of sulfur.

Abstract: The invention relates to a process for degassing and pelletizing polyolefin particles produced by a gas phase polymerization. The polyolefin particles are submitted to a primary degassing, preferably at the outlet of a reactor for catalytic polymerization in the gas phase. Then the polyolefin particles are subjected to a secondary degassing step comprising agitating the particles by a mechanical stirrer and converting the mechanical energy therefrom into heat such that the temperature of the particles is brought to between 80.degree. and 120.degree. C. which is close to minimum sintering temperature Ts so that the polyolefin particles are substantially freed from the gases accompanying them. The heated degassed polyolefin particles are then pelletized in an extruder of a pelleting unit.

Abstract: An improved method of stabilizing a polyoxymethylene copolymer, which comprises(1) heat-melting a crude copolymer of trioxane and a cyclic ether and/or a cyclic acetal to form a first stabilized copolymer having a decomposition ratio (D.sub.220.sup.60), determined when it is heated at 220.degree. C. for 60 minutes in vacuum, of up to 2% by weight, and then(2) bringing the first stabilized copolymer into contact with steam containing 0.01 to 5% by weight of a basic compound at a temperature of at least 100.degree. C. but not exceeding the melting point of the copolymer to form a second stabilized copolymer.

Abstract: A solution polymerization process for the preparation of high molecular weight polymers of alpha-olefins is disclosed. In the process, the coordination catalyst is deactivated using a solution of at least one trialkanolamine deactivating agent of the formula N(ROH)(R'OH).sub.2 where R is isopropyl and R' is alkyl of 2-4 carbon atoms, especially ethyl or isopropyl. The process is capable of producing polyers of improved color.

Abstract: The invention is a process for reducing catalyst residues from a Group VIII metal compound-containing polymer of CO, ethylene and optionally at least one olefinically unsaturated hydrocarbon. The process comprises contacting the polymer with an effective amount of carbon monoxide or a carbon monoxide-containing gas. It is preferable for the process to use a carbon monoxide partial pressure of at least 0.1 bar and a temperature of at least 60.degree. C., which temperature is at least 20.degree. C. higher than that at which the polymers were prepared.

Abstract: The specification discloses a method for assuring consistent and, if desired, increased melt flow rate in a vinyl aromatic based polymer by controlling the degree of absorption of carbon dioxide, oxygen and/or argon for a substantial period of time immediately prior to introduction of the polymer into a molding machine.

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: Electroactive polymers of the structure and formula ##STR1## in their neutral and ionized forms, where the backbone group R.sub.b is selected from or is a combination of five- and six-membered rings capable of aromatic and quinonoid bonding structures, R.sub.s is selected from aliphatic, aromatic and heterocyclic groups and x, y are positive integers from 1 to 5 and m is a positive integer from 2 to about 10,000, together with a method of making them are disclosed.

Abstract: A process and an apparatus for the production of high molecular weight linear polyester is proposed, in which a pumpable material is produced in particular terephthalic acid and an alkaline diol which is esterified in a two or multi-stage reactor arrangement and is subsequently condensed in vacuo in at least one vacuum reactor. The waste heat of the esterification reactor arrangement is used for producing the vacuum in the vacuum reactors. The water for condensing the steam is also obtained from the process steam.

Abstract: A method for removing unpolymerized gaseous monomers from a solid olefin polymer in a single purge vessel while deactivating Ziegler-Natta catalysts and organometallic catalyst residues present in said solid olefin polymer by utilizing a two diameter purge vessel wherein hydrolysis of the catalysts are effected in the portion of the reactor having the smaller diameter with the gaseous monomers being removed in the larger diameter portion.

Abstract: High molecular weight polyester resins such as polyethylene terephthalate, are sometimes produced from low molecular weight polyester prepolymers having the same composition by solid state polymerization. The low molecular weight polyester prepolymers which are used in such solid state polymerizations are normally prepared by conventional melt polymerizations and are generally in the form of pellets or chips. It has been unexpectedly found that solid state polymerization rates can be greatly improved by utilizing polyester prepolymers which are in the form of porous pills. By utilizing polyester prepolymers that are in the form of porous pills, higher molecular weights can be achieved after shorter solid state polymerization times.

Abstract: The deactivation of Ziegler-Natta catalyst and organometallic cocatalyst residues present in the olefin polymer resins produced by the fluidized bed polymerization process is accomplished in a purge vessel by contacting the olefin polymer resin with an inert purge gas containing water the latter being present in said inert purge gas in an amount to establish and maintain a moisture front region in the resin bed of said purge vessel as to create a region above said moisture front substantially free of water and wherein deactivation of said catalyst and cocatalyst are effected in said moisture front region.

Abstract: Moist halogenated resins separated from an aqueous acid suspension of said resins are dried and stripped of residual acid with a heated inert drying gas. The resins are not washed to lower residual acid or treated with a base compound to neutralize residual acid before drying begins. Inert drying gases include nitrogen, helium, argon and the like. The dried resin has low residual acid and moisture levels. It is white and free of visually detectable areas of discoloration. It also has high thermal stability, particularly when admixed with minor amounts of a thermal stabilizer such as calcium stearate.

Abstract: The invention relates to a process for purifying ethylene-alkene-diene rubbers by extraction with an extractant chosen from substances with a critical temperature below 435.degree. K. at a temperature above the critical temperature of the extractant and a pressure above the critical pressure of the extractant.

Abstract: Bringing polymerizates, particularly those comprising styrene polymerized with an equal amount or more acrylonitrile and containing free styrene and acrylonitrile monomers, into contact with carefully selected gases in the near-critical to supercritical state substantially inhibits depolymerization and decomposition while substantially improving residue extraction.

Abstract: The residual monomers, solvents and other impurities particularly in coarse or oversized fat imbibing, fat retaining copolymer beads can be substantially reduced by bringing the copolymer beads into contact with a gas in the supercritical state.

Abstract: Many synthetic latices are produced with a small particle size. It is desirable to increase the particle size and concentrate the latex. It is known to use agglomerating agents to increase particle size. The temperature of agglomeration may be reduced if the latex is destabilized with a weak acid, preferably carbonic acid. This results in an energy saving for the process.

Abstract: The invention relates to a process for the preparation of cellular or noncellular plastics, preferably polyurethane coatings, by reacting at least two components with one another, preferably organic polyisocyanates and polyhydroxyl compounds, by feeding the components into a mixing zone separately, and mixing them together and then discharging the reaction mixture from the mixing zone, while adding air heated to a temperature of 100.degree. to 1200.degree. C. to the reaction mixture as it emerges from the mixing zone.

Abstract: A process for the production of polyester is disclosed, comprising feeding an ester compound made mainly of terephthalic acid and ethylene glycol or an oligomer thereof to a final polymerization reactor, and then polymerizing it in the form of fine molten particles in an inert gas stream, wherein the ester compound has an intrinsic viscosity [.eta.] of not more than 0.4 dl/g and a carboxyl terminal group concentration [COOH] of not more than 90.times.[.eta.].sup.-0.4 .mu.eq/g, and the fine particles have an average particle diameter of from 0.015 to 0.5 mm.

Abstract: High molecular weight polyester resins are sometimes produced from low molecular weight polyester prepolymers having the same composition by solid state polymerization. Polyester prepolymers are generally converted from the amorphous state to the crystalline state prior to solid state polymerization in order to raise their sticking temperature. This is done in order to keep the polyester prepolymer from sticking together as a solid mass in the solid state polymerization reactor. Such polyester prepolymers have traditionally been crystallized by heating them to elevated temperatures. It has been found that polyester prepolymers can be crystallized by exposing them to the vapors of certain volatile organic compounds. By utilizing such vapors to crystallize polyester prepolymers the need for a thermal crystallization step can be eliminated.

Abstract: In a process for producing a formed article of aromatic polyamide-imide resin by compression-molding at the temperature lower than the melting temperature of the resin, the improvement which comprises subjecting the resin, prior to the molding, to heat treatment in an oxygen-containing gas under conditions satisfying the following equationlogt.gtoreq.a.sub.1 +a.sub.2 T+a.sub.3 T.sup.2 +a.sub.4 T.sup.3,wherein a.sub.1 =2.5841, a.sub.2 =-8.4926.times.10.sup.-3, a.sub.3 =6.9984.times.10.sup.-6, and a.sub.4 =-2.0449.times.10.sup.-8 ; t and T represent the heat-treatment time in hour and the heat-treatment temperature in .degree.C., respectively; and 200.degree. C..ltoreq.T.ltoreq.400.degree.C.

Abstract: The present invention relates to the isolation of thermoplastic polycarbonates from their solutions by treating the organic solutions, obtained in the phase boundary processes, of the thermoplastic polycarbonates with vapors of benzene or alkylbenzenes.

Abstract: A process for the production of polyester comprising at least 80% of an ethylene terephthalate repeating unit using as a starting material an ester compound made mainly of terephthalic acid and ethylene glycol or an oligomer thereof is disclosed. This process is characterized in that a prepolymer having an intrinsic viscosity of not more than 0.4 dl/g and a carboxyl terminal group concentration [COOH] of not more than 90.times.[.eta.].sup.-0.4 .mu.eq/g is fed to a final polymerization unit and polymerized in the form of a molten thin film having a thickness of from 0.005 to 0.15 mm.

Abstract: Polyethylene terephthalate (PET) produced by direct esterification of a mixture containing ethylene glycol and terephthalic acid in a mole ratio ranging from about 1.05 to about 1.35 dl/g, with at least about 325 parts of an antimony catalyst per million parts of polymer product, can be treated to reduce its acetaldehyde content and acetaldehyde generation rate and increase molecular weight to the levels required for the production of beverage bottles. After heat treatment to produce a crystallinity of at least about 10 percent, the PET can be used in molding after substantially conventional pre-drying and drying steps in air at the molding facility. The invention thus allows beverage bottle grade PET to be produced and prepared for molding without the conventional step of solid state polymerization or stabilization, saving energy, time, production costs and capital investment.

Abstract: A method is provided for separating metal catalyst contaminants from organic polymers, typically polymers derived from dienes and/or vinyl arenes, by treatment with a dicarboxylic acid and an oxidant which forms an insoluble metal compound, then separating the insoluble compound to remove the contaminating metal.

Abstract: A method for reducing the volatile component content of crude high molecular weight polyesters containing said component. The method comprises first contacting the crude polyester with steam, or a mixture of steam and inert gas and/or air, at a temperature of 100.degree. to 245.degree. C. to form a partially treated polyester. The second step comprises further contacting the product of the first step with an inert gas and/or air at a temperature of 200.degree. to 245.degree. C. to produce the purified polyester.In particular, the method is intended for use with such polyesters as polyethylene terephthalate which contains acetaldehyde as the undesired volatile component.A new method of analysis useful in the foregoing process is also disclosed. The products of the new process are primarily intended for use in the manufacture of plastic bottles or similar containers for use in the foodstuffs industry.

Abstract: The present invention is directed to a method and apparatus for the detoxification of polymeric film chip materials which have been contaminated with cyanide compounds during the process for the reclamation of their silver content. The present invention includes the steps of providing within a substantially impervious container a quantity of polymeric film chip materials containing a cyanide compound, and then submerging the cyanide containing polymeric film chip materials in a solution containing hypochlorite ion at a pH of approximately 9.5 to 10.5 until the cyanide in the polymeric film chip material is substantially converted into cyanate. In preferred alternative embodiments the treatment solution is replaced with a second treatment solution containing hypochlorite ion and having a pH of approximately 7.5 to 8 until the cyanate is substantially converted into carbon dioxide and nitrogen gases. Mixing means in the form of influent and effluent means are provided in such apparatus.

Abstract: Described are a process and an apparatus for the aftercondensation of polycondensates, wherein moist and amorphous polymer in a granular or powderous form is continuously introduced from above into a single reactor. The granulate flows downward under gravity, with a hot gas being caused to flow in counter-current relation thereto. The reactor is formed as a continuous shaft or column which has positioned in the upper portion thereof an agitating element acting to prevent agglutination of the granulate. The granulate is crystallized and pre-dried in the upper portion of the shaft or column. In a further (subsequent) portion of the shaft or column, drying and aftercondensation take place without separation from the remainder of the shaft or column.

Abstract: A method for removing residual solvent dissolved in non-sticky crumb particles produced by solution polymerization that have been treated substantially to remove solvent from the polymer surface. Particles are transferred into a closed storage zone under inert atmosphere conditions and are maintained for a period of time sufficient to allow diffusion of solvent from the particles as free solvent. Inert gas is then passed through the storage zone to remove the free solvent. The processes of allowing diffusion followed by purging of the free solvent is repeated as necessary.

Abstract: The present invention involves a method of treating solutions of hydrogenated conjugated diene polymers contaminated with residues of nickel hydrogenation catalysts, wherein the solutions are first oxidized and then contacted with a ligand which readily forms a stable nickel compound.

Abstract: A method for removing trace amounts of contaminating hydrazine from pharmaceutical grade PVP. An aqueous solution of PVP is contacted with a gaseous stream containing ozone for a period of time sufficient to remove the hydrazine.

Abstract: Polyesters are often polymerized to higher molecular weights in the solid state in the presence of an inert gas stream. The inert gas stream removes volatile reaction products and helps to heat the polyester. It has been found that the amount of inert gas needed to solid state polymerize a polyester can be greatly reduced by pulsing the inert gas through the polyester.

Abstract: When producing molded foam parts from liquid reaction components, the charge of gas in the initial components has a significant effect on the foam structure and quality of the molded part. This invention provides a process and apparatus for introducing a gas into at least one of the liquid reaction components prior to mixing said components for reaction. The component which is to be charged with gas is circulated from a feed tank through a recycle circuit to a compression zone which is maintained at a higher pressure than that of the feed tank. Said gas is admixed with said component at the point of initiation of the compression zone and the higher pressure is relieved through a throttle element prior to returning the gas-charged component to the feed tank. A finely divided stable gas dispersion which can be mixed with other components for reaction is obtained.

Abstract: Benzene is removed from carboxy polymethylene resin by dissolving the resin to form a solution and dispersing the solution as fine droplets in a gas phase or aerating the solution to introducing into it a fine dispersion of gas bubbles. The benzene transfer from the solvated resin to the gas phase and a benzene-free resin or solution can be obtained which may be usable in pharmaceutical and food products.

Abstract: A method of polymerizing a thermosetting resin such as an epoxy resin charged with silver particles in which shaped bodies of the resin are brought cold into contact with vapor of an organic liquid boiling at a temperature of above 100.degree. C. so that a condensate from this liquid forms on the bodies in temperature equilibrium so that the heat of vaporization is transferred upon such condensation rapidly to the bodies and the latter are polymerized rapidly under the constant temperature and pressure conditions.

Abstract: A system for recovering vapor, such as residual isobutane, from powder, such as polyethylene powder, comprises surge vessel and a two-compartment purge column. The polymer passes through the surge vessel by means of valves such as ball valves on the inlet and outlet of the surge vessel. Hot vapor, such as isobutane, is used to strip a large portion of the residual isobutane from the polyethylene in the top section of the purge column. Part of the isobutane leaving the column goes to a hydrocarbon recovery section and part is heated and recycled as the stripping medium. In the bottom section, nitrogen is used to strip the remaining isobutane from the polymer. An analyzer controller sensing nitrogen in the isobutane stream to recovery controls pressure in the bottom section by manipulating a valve in the nitrogen off-gas line from the bottom section to control the nitrogen content of the isobutane stream being recycled as stripping medium.

Abstract: An epoxy resin composition is provided which contains carbon dioxide as a cure retardant. The composition comprises an epoxy resin, a curing agent for the epoxy resin, a hydrocarbon diluent and carbon dioxide. It can optionally contain an alcohol. The presence of the carbon dioxide enables preparation of an epoxy resin and curing agent solution which can be stored and transported to the site of application without curing of the resin until after application. The composition is useful, for example, as a corrosion inhibitor for metal surfaces, and is particularly useful for downhole metal equipment at oil and gas drilling sites.

Abstract: Method to condition water-swellable hydrocolloids for use in mechanical forming processes such as die molding or injection molding. To avoid long conditioning times at high temperature, the hydrocolloids are conditioned to the predetermined water content at ambient temperature and then rapidly heated, just before processing, in a gaseous stream loaded with water to the equilibrium conditions needed to maintain the predetermined water content of the hydrocolloids at the high process temperature of the mechanical forming.

Abstract: In manufacturing a photographic support by coating a travelling paper substrate with a polyolefin resin, the adhesion of the resin to the substrate can be markedly improved by subjecting the uncoated paper substrate to an activation treatment on the side to be subsequently coated with the polyolefin resin and exposing the side of the molten polyolefin resin to be brought into contact with said paper substrate to an ozone-containing gas blown against said molten resin. This method leaves behind no adverse effect on the photographic emulsion which is subsequently applied and permits of marked improvement of the productivity at a low cost.

Abstract: A process for the post condensation of poly(alkylene terephthalate) in the solid phase is carried out in the presence of esters of phosphorous acid at 25.degree.-65.degree. C. below the melting point of the poly(alkylene terephthalate) while passing an inert gas stream through the reaction mixture.

Abstract: A process of removing solvents from polymer solutions is made more efficient by the use of a prestripping operation during which substantially none of the polymer precipitates from solution.

Abstract: Epichlorohydrin levels in heat sensitive glycidyl products are reduced from a few thousand ppm, an unacceptable level, to only a few ppm or to a non-detectable level by use of a multistage stripping column with or without inert gas purging without decomposition of the heat sensitive glycidyl products. Such glycidyl products are useful in epoxy resins particularly as crosslinking agents.

Abstract: A process for crosslinking a polycarbonate resin involves heating the polycarbonate resin in the presence of an organic copper compound at a temperature higher than the glass transition point of the polycarbonate resin.

Abstract: A process for condensing a linear polyalkylene terephthalate having a viscosity number of at least 60 cc/g in two stages, at an elevated temperature, in the solid phase, and in the presence of an alkanediol, comprises, in a first stage, treating the polyalkylene terephthalate in an inert gas stream at a reaction temperature 30.degree.-80.degree. C. below its melting point, with 0.2-3.5% by weight, based on the weight of the polyalkylene terephthalate, of an alkanediol whose boiling point under normal pressure is 20.degree.-70.degree. C. above the reaction temperature, wherein the amount of inert gas passed through per hour, measured under standard conditions, corresponds to 0.3 to 2 times the gross reactor volume; and, in a second stage, condensing the polyalkylene terephthalate in an inert gas stream at a temperature 5.degree.-25.degree. C. below its melting point, wherein the amount of inert gas passed through per hour, measured under standard conditions, corresponds to 2.

Abstract: Method for removing chlorinated solvents from chlorinated polymers which retain them as a result of a chlorination process, wherein after being dried and pulverized, said chlorinated polymer is treated with a non-halogenated aliphatic organic solvent or a halogenated aromatic organic solvent. Said organic solvent pertains to the following groups: alcohols such as methanol, ethanol, isopropanol; esters such as methyl formate, ethyl formate, methyl acetate; nitriles such as acetonitrile; aromatic halides such as chlorobenzene; hydrocarbons such as n-hexane; and acetone.