Abstract: Aqueous dispersion of a polymer, which polymer has been obtained by subjecting a starting polymer which contains maleic anhydride monomer units and vinyl aromatic monomer units to an imidization reaction, the starting polymer containing 7-50 mole % maleic anhydride monomer units and the imidization reaction having been carried out in such a way that at most 75% of the maleic anhydride monomer units has been imidized.

Abstract: A process for purifying a polycarbonate resin solution which comprises passing a water-in-oil dispersion type (W/O) emulsion composed of a mixture of an organic solvent solution containing a polycarbonate resin with a aqueous solution and having water particles with an average diameter of 1 to 100 &mgr;m in an oil through a metallic filter having a filtering precision of 10 to 200 &mgr;m, and then, settling the mixture for 1 to 30 minutes to perform separation between the organic solvent solution containing a polycarbonate resin and the aqueous solution containing contaminations.

Abstract: A polyacetal resin composition comprising 30-90% by weight of polyacetal copolymer (A) having a melt index of less than 1.0 g/10 min. and 70-10% by weight of polyacetal copolymer (B) having a melt index of 1.0-100 g/10 min., both melting points of (A) and (B) being 155°-162° C., or a difference in melting point between (A) and (B) being not less than 6° C., has distinguished toughness and creep resistance.

Abstract: A polyaspartic acid is obtained from an amino acid having aspartic acid as an essential component thereof without entailing formation of a bulk substance. A method for the production of polyaspartic acid is described which includes heating an amino acid having aspartic acid as an essential component thereof in the presence of water. A novel polyaspartic acid obtained by this method of production is described.

Abstract: The present invention provides a method of recovering a polyamine compound and/or a polyol compound useful for starting materials of polyurethane resin in an industrially advantageous manner by first dissolving the polyurethane resin such as polyurethane foams discharged in a large amount as industrial wastes in a solubilizing agent containing a polyamine compound, a low molecular glycol or an amino alcohol, hydrolyzing the resulting solution with liquid water at 200 to 320° C., then recovering the polyamino compound and/or polyol compound thus formed.

Abstract: An absorbent composition comprising an uncrosslinked, high molecular weight polymer, wherein the uncrosslinked, high molecular weight polymer is treated by a means to effectively insolubilize the uncrosslinked, relatively high molecular weight polymer such that the absorbent composition exhibits desirable absorbent properties. In particular, the absorbent composition has the ability to absorb a large quantity of liquid. The absorbent composition is useful in disposable absorbent products, such as those disposable absorbent products that are used to absorb bodily liquids. Suitable polymers include polyethylene oxide, poly(acrylic acid), poly(vinyl alcohol), and poly(vinyl pyrrolidone) wherein the polymer has a weight average molecular weight that is greater than about 1,000,000.

Abstract: The present invention provides a process for producing a hydroxyalkyl (meth)acrylate which comprises the step of carrying out a reaction between (meth)acrylic acid and an alkylene oxide, wherein the process provides enablement for economically and efficiently recovering and recycling the unreacted residue of the alkylene oxide. The process for producing a hydroxyalkyl (meth)acrylate comprises the steps of, carrying out a reaction between (meth)acrylic acid and an alkylene oxide; stripping the unreacted residue of the alkylene oxide from the resultant reaction liquid; and causing a solvent to absorb the stripped alkylene oxide; wherein: water is used as the absorbing solvent; and an absorbing liquid resultant from the absorption of the unreacted residue of the alkylene oxide is used for production of an alkylene glycol.

Abstract: A process for producing a polyphenylene ether, which comprises contacting, with an aqueous solution of a chelating agent, a polyphenylene ether solution and adding a water-soluble poor solvent for the polyphenylene ether to precipitate the polyphenylene ether; and recovering the thus precipitated polyphenylene ether. A mixture remaining after the recovery of the polyphenylene ether is brought into contact with water to extract the water-soluble poor solvent, and a water phase containing the thus extracted water-soluble poor solvent is recovered by separation. The water-soluble poor solvent is separated and removed from the water phase by distillation, and the whole or a part of the remaining water phase is recycled as water to be brought into contact with the mixture, the remaining water phase having a content of a high-boiling-point organic substance of 1 wt. % or less.

Abstract: A method for removing volatile components from wet, solid polymeric materials on a vacuum vented extruder is described. Polymeric materials containing substantial amounts of water, 1-20 % by weight, are rapidly converted to polymer compositions containing less than about 0.5% by weight water at high throughput rates while avoiding complications resulting from excessive steam backflow through the extruder feed throat. The method utilizes a screw design comprising only forward flighted screw elements in an initial polymer melting and kneading zone. Steam generated as the polymer is heated and sheared flows downstream to a first vacuum vent for removal. The partially devolatilized polymer melt is then subjected to additional kneading and vacuum venting. The claimed method converts wet polycarbonate powder containing residual methylene chloride to essentially dry polycarbonate powder containing less than about 1 ppm methylene chloride.

Abstract: A process of controlling the molecular weight and dispersity of poly(p-ethylphenol) and poly(m-cresol) synthesized enzymatically by varying the composition of the reaction medium. Polymers with low dispersities and molecular weights from 1000 to 3000 are synthesized in reversed micelles and biphasic systems. In comparison, reactions in bulk solvents resulted in a narrow range of molecular weights (281 to 675 with poly(p-ethylphenol) in a DMF/water system and 1,400 to 25,000 with poly(m-cresol) in an ethanol/water system). Poly(p-ethylphenol) was functionalized at hydroxyl positions with palmitoyl, cinnamoyl, and biotin groups.

Abstract: A process of controlling the molecular weight and dispersity of poly(p-ethylphenol) and poly(m-cresol) synthesized enzymatically by varying the composition of the reaction medium. Polymers with low dispersities and molecular weights from 1000 to 3000 are synthesized in reversed micelles and biphasic systems. In comparison, reactions in bulk solvents resulted in a narrow range of molecular weights (281 to 675 with poly(p-ethylphenol) in a DMF/water system and 1,400 to 25,000 with poly(m-cresol) in an ethanol/water system). Poly(p-ethylphenol) was functionalized at hydroxyl positions with palmitoyl, cinnamoyl, and biotin groups.

Abstract: The present invention relates to a quick set composition and a method for preparing the composition. The composition comprises an aqueous sol of a polymer having a backbone that contains pendant cationic groups and pendant acid groups. The sol is prepared by forming a solution of a polymer that contains pendant cationic groups and pendant acid groups in an aqueous-based solvent that contains water and a suitable organic solvent and removing a sufficient amount of the organic solvent from the solution to form a composition characterized by being reversibly dissolvable and reconstitutable by addition and removal of a suitable organic solvent. The composition of the present invention provides quick-set films that can be prepared in the absence additional surface active agents and with a substantial absence of organic solvents.

Abstract: Process of gelification of aqueous medium with a copolyester oligomer comprising essentially oxyalkylenated or ocycycloalkylenated or polyoxyalkylenated dicarboxylate units at least 35 mole % of said units being similar units of which the correspondent homolymer is crystalline, at least 7 mole % of said units being bearing units of hydrophobic(s) sulfonated functions, the molecular mass in weight of said copolyesters oligomer being less than 20.000. For example: the terephtalic polyoxyethylenated sulfonated oligomers of high content of polyethyleneterephtalate.

Abstract: A soft hydrogel containing a triblock copolymer and water is disclosed. The copolymer has formula (I): X-G-Y, wherein G is a non-hydroxylated hydrophilic linear polymer block containing p repetitive units, where p is a number from 10 to 150, each of X and Y is a polyester block containing m and n repetitive units, respectively, and the ratio (m+n)/p is high enough for said copolymer to be water-insoluble, said ratio (m+n)/p being selected in such a way that adding water to a solution of the copolymer in a water-miscible organic solvent leads to the formation of a soft hydrogel capable of retaining an amount of water at least as great as the weight of said copolymer. Said hydrogel is suitable for retaining and gradually releasing hydrophobic substance and/or hydrophilic macromolecules, including drugs.

Abstract: A process is disclosed for producing with good productivity a cross-linked polyaspartic acid resin having biodegradability and high water absorbency. The process features inclusion of one of the following steps: (a) a polysuccinimide, which has been brought into a dispersed state by a dispersant, and a cross-linking agent are reacted to produce the cross-linked polyaspartic acid resin; (b) imide rings of a cross-linked polysuccinimide are subjected to a hydrolysis reaction while controlling a swelling degree of a resulting gel, whereby the cross-linked polyaspartic acid resin is produced; and (c) a gel of a cross-linked polysuccinimide, which has been obtained by reacting a cross-linking agent to a solution of a polysuccinimide in an organic solvent, is disintegrated to subject imide rings of the cross-linked polysuccinimide to a hydrolysis reaction, so that the cross-linked polyaspartic acid resin is produced.

Abstract: A process is provided to recover at least one modifier compound and at least one polar organic compound from a reaction mixture comprising high molecular weight Poly(arylene sulfide) product, low molecular weight P(AS), cyclic and linear P(AS) oligomers, at least one POC, at least one modifier, an alkali metal halide by-product, and water.

Abstract: A process for continuous extraction of polyamide particles using a recirculating extractant in a vertical extraction column that is divided into two zones comprises treating the polyamide with an aqueous extractant comprising from 40 to 95% by weight of &egr;-caprolactam in a first zone at from 100 to 140° C., and then effecting an aftertreatment with water in a second zone. The caprolactam can then be extracted in a conventional manner. The process provides for economical production of polyamide having a low dimer content.

Abstract: Polyamide particles, or polymer particles comprising polyamides, are extracted with aqueous solutions of aminonitiles and optionally further polyamide-forming monomers, polyamide-forming oligomers or mixtures thereof.

Abstract: The present invention provides a method of producing a chlorinated rubber wherein an acidic or highly acidic chlorinated rubber cake obtained after chlorinating a rubber latex or an aqueous dispersion is subjected to fluidized drying together with a drying medium to obtain a preliminary dried powder, and the preliminary dried powder is subjected to fluidized drying again. According to the present invention, a high quality chlorinated rubber can be obtained efficiently with easy handling from an acidic or highly acidic chlorinated rubber cake obtained after chlorinating a rubber latex or an aqueous dispersion.

Abstract: Methods and apparati have been developed for producing a suspension of predominately amorphous polymer particles, wherein the method includes thermally treating a suspension that includes crystalline or semi-crystalline polymer particles. The thermal treatment includes (a) heating a suspension of polymer particles of an appropriate size to a temperature effective to cause the polymer to become amorphous, and then (b) cooling the suspension of amorphous polymer particles below the melting point of the polymer at a rate effective to prevent substantial coalescence of the polymer particles. The method and apparati are effective for use with a variety of polymers having suitable crystallization parameters, although polyhydroxyalkanoate (PHA) polymers are preferred, particularly in an aqueous suspension medium. For PHA polymers, the polymer particles subjected to treatment preferably are of a size of less than 5 &mgr;m, or more preferably less than 1.5 &mgr;m in diameter.

Abstract: The present invention provides a process for preparing polyethylene naphthalate polymers comprising: esterifying a slurry comprising NDCA or a dicarboxylic acid containing NDCA or derivatives thereof, and ethylene glycol or a glycol containing ethylene glycol or derivatives thereof to produce esterification compounds comprising bis (beta-hydroxyethyl) naphthalate or low molecular weight polymers thereof, wherein one or more primary alcohol is added to the slurry; and polycondensing the above resultant esterification compounds to produce polyethylene naphthalate polymers. The process of the present invention allows for the preparation of a slurry more easily and to maximize the manufacturing efficiency.

Abstract: A process for continuous extraction of polyamide particles in an essentially vertical extraction column using an aqueous extractant comprises using an extraction column that is divided into two zones and performing an extraction with a recirculating 15-40% strength by weight aqueous &egr;-caprolactam solution in the first zone and then with countercurrent water at a from 5 to 40° C. lower temperature in the second zone. The process provides for economical extraction of polyamides with a low level of monomers and oligomers.

Abstract: A process is provided to recover at least one modifier compound and at least one polar organic compound from a P(AS) recycle mixture.

Abstract: The pelletized product of melt condensation polymerization of 1,3-propanediol and terephthalic acid (or alkyl ester thereof) is crystallized by immersion in water at a temperature within the range of 60 to about 100° C. Hot-water treatment increases the crystallinity of the polymer to at least about 35% and increases pellet density to about 1.33 g/cm3.

Abstract: Disclosed is a method for closely linking a process for producing 2,6-naphthalene dicarboxylic acid (2,6-NDA) with a process for producing polyethylene naphthalate, thus eliminating the need for drying 2,6-NDA, handling solid 2,6-NDA, and optimizing particle size of 2,6-NDA which comprises: a) Adding an aqueous slurry of polymer grade 2,6-NDA directly into a process for making PEN, either by directly adding a stream from a 2,6 NDA process into a PEN process, or by adding water to polymer grade 2-6-NDA prior to adding the resulting slurry to a PEN process. b) Removing the slurry water during the first esterification reaction at the same time the water of reaction is removed.

Abstract: Thermally stable polymers comprising resorcinol arylate chain members are prepared using an interfacial method comprising the steps of: (a) combining at least one resorcinol moiety and at least one catalyst in a mixture of water and at least one organic solvent substantially immiscible with water; and (b) adding to the mixture from (a) at least one dicarboxylic acid dichloride while maintaining the pH between 3 and 8.5 through the presence of an acid acceptor, wherein the total molar amount of acid chloride groups is stoichiometrically deficient relative to the total molar amount of phenolic groups.

Abstract: Methods and apparati have been developed for producing a suspension of predominately amorphous polymer particles, wherein the method includes thermally treating a suspension that includes crystalline or semi-crystalline polymer particles. The thermal treatment includes (a) heating a suspension of polymer particles of an appropriate size to a temperature effective to cause the polymer to become amorphous, and then (b) cooling the suspension of amorphous polymer particles below the melting point of the polymer at a rate effective to prevent substantial coalescence of the polymer particles. The method and apparati are effective for use with a variety of polymers having suitable crystallization parameters, although polyhydroxyalkanoate (PHA) polymers are preferred, particularly in an aqueous suspension medium. For PHA polymers, the polymer particles subjected to treatment preferably are of a size of less than 5 &mgr;m, or more preferably less than 1.5 &mgr;m in diameter.

Abstract: Aromatic polyamide fibers which have a crystalline structure having (1) crystal size (A) in a (110) plane of 7.5 nm, (2) crystal size (B) in a (200) plane of 8.2 nm and (3) a product A×B of 61.50 to 630.00, and exhibit a thermal linear expansion coefficient of −1.0×10−6/° C. to −7.5×10−6/° C. and thus a high dimensional stability even upon moisture-absorbing and desorbing, are useful for forming a resin-reinforcing fiber sheet, a pre-preg containing the fiber sheet, and a laminate for, for example, an electric insulating material or electric circuit board, having an excellent cutting, shaving, perforating or laser processability and capable of forming a smooth cut, shaved or perforated face.

Abstract: Doped polyanilines are prepared by contacting aniline with an oxidizing agent such as ammonium peroxydisulfate in aqueous solution at a temperature of at most about 10° C. in the presence of at least one organic sulfonic acid, preferably an alkylbenzenesulfonic acid such as dodecylbenzenesulfonic acid. The products may be blended with thermoplastic resins such as polystyrene to produce blends having excellent static discharge properties.

Abstract: The present invention relates to stable aqueous polymer dispersions and a process for their preparation. The aqueous dispersions of the invention have less than about 2 weight percent organic solvent, at least about 30 weight percent solids, a mean particle size of not more than about 300 nm, and a viscosity of less than about 20.0 poise at about ambient temperature.

Abstract: Provided are processes by which an ethylenimine polymer and an aqueous solution thereof can advantageously be produced at low costs in an industrial scale. The ethylenimine polymer can be produced by polymerizing crude ethylenimine obtained by a simple distilling operation from an ethylenimine-containing reaction mixture produced by subjecting ethanolamine to intermolecular dehydration reaction, preferably crude ethylenimine having impurity contents which are controlled in the specific ranges. When the above crude ethylenimine is polymerized in an aqueous medium, capable of being obtained is an aqueous solution of an ethylenimine polymer having a higher molecular weight than that produced by non-solvent polymerization. The ethylenimine polymer can be purified by, for example, adding water thereto, mixing them and then vaporizing and removing water under heating. The aqueous solution of an ethylenimine polymer can be purified by heating and condensing it.

Abstract: An ocular lens material comprising a polymer prepared by polymerizing a polymerizable component for an ocular lens, containing (A) 20 to 50% by weight of a silicon-containing alkyl acrylate, (B) 20 to 50% by weight of a polysiloxane macromonomer in which a polymerizable group bonds to a siloxane main chain through at least one urethane bond, (C) 10 to 50% by weight of at least one of hydroxyalkyl acrylates and at least one of hydroxyalkyl methacrylates, and (D) 0.01 to 10% by weight of a crosslinkable compound having at least two polymerizable groups, and a process for producing the same. The ocular lens material shows excellent stain resistance and excellent flexibility at the same time in addition to excellent transparency, and can be easily produced by the process.

Abstract: A method for continuously stripping an unreacted monomer from a vinyl chloride paste resin latex, comprising the steps of continuously supplying the latex to a vacuum recovery vessel, wherein the latex is boiling with generation of foam, under the condition that the temperature of the latex to be supplied is higher than that of the latex in the recovery vessel, withdrawing a monomer gas generated in the recovery vessel through an exhaust line provided with a foam separator, contacting the foam entrained into the exhaust line with steam introduced to the exhaust line and/or the foam separator, thereby destroying the foam, and returning the resulting latex in the separator to the recovery vessel. The unreacted monomer can be efficiently recovered from the latex by a continuous operation, and defoaming can be achieved without deteriorating the quality and without lowering the productivity.

Abstract: An optical molding material which is an aromatic polycarbonate resin pellet, wherein the amount of fine powders, produced from 5 kg of the pellets mixed in a vessel for 1 hour and having a particle diameter of 1.0 mm or less, is 300 ppm or less. The formation of carbide during molding can be suppressed by using the pellets of the present invention.

Abstract: Method for the manufacture of a phenolic resin emulsion and/or dispersion, wherein an aldehyde, a phenolic compound and an alkaline catalyst are allowed to react at a temperature of 40-100° C. until a desired degree of condensation is achieved, and the pH of the resin is adjusted to a value below 9 using an acid in the presence of a surface active agent or a mixture thereof at a temperature below 100° C. and a phenolic resin emulsion and/or dispersion is obtained providing a colorless or light-colored glue line or surface when cured.

Abstract: A process for granulating a polyamide resin involving: (a) providing an underwater granulating device having a heated multiple-bore die wherein the bores have an internal diameter ranging from 1.2 to 2.5 mm and a length of from 12 to 50 mm; (b) providing a polyamide resin melt having a viscosity, at 160° C., of less than 3,000 mPas; (c) cooling the polyamide resin melt to form a cooled polyamide resin; (d) introducing the cooled polyamide resin into and through the heated multiple-bore die to form an extrudate; (e) providing a source of water; (f) contacting the extrudate with the water to form a cooled extrudate; and (g) cutting the cooled extrudate into granules.

Abstract: A process for preparing an aqueous dispersion coating material containing a resin component having a softening temperature of from 10 to 250° C., which comprises: (1) a step of mixing various starting materials which will be coating film-constituting components, to obtain a blend material, (2) a step of melting and kneading the blend material at a temperature of at least the softening temperature of said resin component, to obtain a homogenized material, (3) a step of cooling and solidifying the homogenized material, followed by crushing, to obtain coarse particles, and (4) a step of wet-pulverizing the coarse particles in an aqueous dispersant, to obtain an aqueous dispersion coating material containing fine particles having an average particle size of at most 10 &mgr;m.

Abstract: Methods and apparati have been developed for producing a suspension of predominately amorphous polymer particles, wherein the method includes thermally treating a suspension that includes crystalline or semi-crystalline polymer particles. The thermal treatment includes (a) heating a suspension of polymer particles of an appropriate size to a temperature effective to cause the polymer to become amorphous, and then (b) cooling the suspension of amorphous polymer particles below the melting point of the polymer at a rate effective to prevent substantial coalescence of the polymer particles. The method and apparati are effective for use with a variety of polymers having suitable crystallization parameters, although polyhydroxyalkanoate (PHA) polymers are preferred, particularly in an aqueous suspension medium. For PHA polymers, the polymer particles subjected to treatment preferably are of a size of less than 5 &mgr;m, or more preferably less than 1.5 &mgr;m in diameter.

Abstract: A hydrophobic textile product of the present invention is obtained through graft polymerization of an ethylenically unsaturated organic acid. The textile product characterized by: a graft polymerization rate of about 8 wt % or more; substantially no agglutination of a byproduct polymer from the graft polymerization process; a hygroscopicity of about 2.5 wt % or more under a 20° C.×65% RH environment; and an ammonia deodorizing property.

Abstract: Devolatilization of molten polymer is carried out using a vertical static mixer which opens directly into a flash tank. Expansion of a stripping agent injected at an inlet of the static mixer occurs in the static mixer and the continued shearing causes disengagement of the vapor from the polymer, so that expansion is complete before the polymer enters the flash tank and stripper and volatiles are removed by a pump and condenser arrangement which holds the flash tank at a reduced pressure. Polymer outlets are in the floor of the flash tank and have metering pumps at their bottom end.

Abstract: A novel treatment and recovery process is provided which produces commercially desirable high molecular weight poly(arylene sulfide)s from undesirable low molecular weight poly(arylene sulfide)s. The novel process reduces the quantity of low molecular weight poly(arylene sulfide)s which otherwise have little or no commercial value and can require disposal.

Abstract: In a method of making repositionable pressure sensitive adhesive of tacky elastomeric microspheres wherein the microspheres are polymerized and formed in an aqueous suspension which includes a surfactant, a certain amount of the surfactant is removed from the aqueous suspension after completion of polymerization of the microspheres so that a predetermined reduced amount of surfactant remains, with the result that migration of the surfactant from the adhesive is at least substantially reduced.

Abstract: The sulfonation of a polyaniline or a derivative thereof by the use of a sulfonating agent, characterized by dispersing the polyaniline or the derivative thereof in a reaction solvent thereby inhibiting the formation of lumps of grains due to substantial aggregation. Preferably, the solvent for the reaction is an organic solvent incapable of reacting with the sulfonating agent. The initial stirring power for the reaction of sulfonation is preferred to be not less than 0.03 kW/m3 and the polyaniline or the derivative thereof is preferred to have a water content of not more than 8 wt. %. Further, this invention is characterized by subjecting a polyaniline having introduced a sulfonic acid group therein or a derivative thereof to hydrolysis in a mixed solution of water with a hydrophilic organic solvent. The hydrophilic organic solvent is preferred to be an alcohol.

Abstract: Nylon 6 chip is obtainable by hydrolytic polymerization of caprolactam in the presence of dicarboxylic acids as chain regulators, subsequent processing of the polymer melt into chip, extraction of the low molecular weight portions from the chip with water and subsequent drying of the chip.

Abstract: The present invention provides a production process, in which hydrophilic crosslinked polymers can be dried uniformly with good efficiency, and the deterioration during the drying is little. The production process of a hydrophilic crosslinked polymer comprises the steps of polymerizing an aqueous solution including a hydrophilic monomer and a crosslinking agent to obtain a hydrogel crosslinked polymer, and drying the hydrogel crosslinked polymer, thus obtaining the hydrophilic crosslinked polymer, and is characterized in that: the hydrogel crosslinked polymer is dried in a static state until it becomes possible to disintegrate an aggregate of the hydrogel crosslinked polymer; the dried hydrogel crosslinked polymer is disintegrated into a particle size of 20 mm or less; and the disintegrated hydrogel crosslinked polymer is dried in a stirred state and/or a fluidized state.

Abstract: A process for the recovery of methyl polysiloxane in the form of methyl cyclosiloxane of the general formula (R2SiO)x, wherein R is selected from alkyl, alkenyl, aryl and alkaryl groups and “x” is an integer selected from 3-6, in which: a) liquifying silicone feedstock as herein defined is liquefied in a solvent selected from alcohol or siloxane in presence of a catalyst at a temperature of between 110° C.-180° C. to obtain a liquefied mass consisting of a mixture of methyl polysiloxane, solvent and filler; b) adding a metal hydroxide to the liquefied mass so as to convent the fillers to their corresponding silicates, the said silicates thus obtained are removed and the liquid recovered; and c) cyclyzing methyl polysiloxane in the liquid medium thus obtained in the presence of a cracking catalyst in the temperature range of 115-160° C. so as to crack the liquid methyl polysiloxane to a mixture of volatile methyl cyclosiloxane.

Abstract: Wear resistance and oxidation resistance of polymer material or a polymer component for bioimplantation are improved by packaging a polymer object in a sealed gas impermeable package substantially free of oxygen, irradiating the package with penetrating radiation to an extent sufficient to effect a desired substantial level of cross-linking within the polymer, and warming the packaged object while maintaining an elevated hydrostatic pressure to cause gases released during irradiation to recombine, stabilizing the material against subsequent oxidative change. The pressure stabilization terminates active sites, substantially eliminating free radicals. When applied to finished parts, the process simultaneously hardens and sterilizes the parts without degrading mechanical properties or dimensions. When applied to bulk material or unfinished parts, the part may be subsequent machined or otherwise finished, and sterilized by any conventional means.

Abstract: Disclosed are reduced salt polyallylamine polymer compositions, a process for producing a cross-linked polyallylamine polymer from a reduced salt, aqueous solution of a polyallylamine polymer and a multifunctional cross-linking agent and to cross-linked polyallylamine polymer compositions produced thereby.

Abstract: A method is provided to hydrogenate a polymer containing ethylenic unsaturation comprising the steps of: providing a solution or suspension of the polymer containing ethylenice unsaturation with an amount of Group VIII metal alkoxide or carboxylate and metal alkyl hydrogenation catalyst effective to permit hydrogenation of the ethylenic unsaturation upon exposure to hydrogen; exposing the polymer solution or suspension to a hydrogen partial pressure for a time period sufficient to hydrogenate greater than about 90 percent of the ethylenic unsaturation; adding additional Group VIII metal alkoxide or carboxylate and metal alkyl hydrogenation catalyst to the polymer solution or suspension after greater than about 90 percent of the ethylenic unsaturation has been hydrogenated; mixing the hydrogenated polymer solution or suspension with the additional Group VIII metal alkoxide or carboxylate and metal alkyl hydrogenation catalyst with an aqueous solution of an acid; and separating a hydrogenated polymer solution o

Abstract: A process for the recovery of an initially living polymer from a cement produced in a polymerization process. The living polymer cement is shortstopped, washed, stabilised, coagulated and dried. The recovery process comprises adding a short stop to the polymer in the cement, washing catalyst residue from the polymer with water, adding an antioxidant Irganox 1520 to the cement to stabilise the polymer, adding epoxidised soya bean oil to the polymer to stabilise the polymer against colour degradation, and coagulating and drying the polymer. The pH of the cement is regulated in the range of from about 3 to about 7, and preferably from about 6 to about 7, during the catalyst wash and the coagulation steps of the recovery process. A product of the process is also described.