Abstract: In order to produce inexpensively with high productivity a water-absorbent resin of which: the residual monomer content and the water-extractable content are both low, and the properties are high, and the colorability is low; there is provided a process for producing a water-absorbent resin, which is a process for producing a crosslinked water-absorbent resin by polymerizing a monomer component including acrylic acid and/or its salt in a major proportion wherein the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane, with the process being characterized by comprising the steps of: preparing the monomer component from an acrylic acid composition that includes the unneutralized acrylic acid and a methoxyphenol and has a methoxyphenol content of 10 to 160 ppm by weight (based on the unneutralized acrylic acid); and then carrying out radical and/or ultraviolet polymerization of the resultant monomer component.

Abstract: To provide: a process in which a coarse gel itself is made not to form in the case of applying the aqueous solution polymerization; and a process in which the polymerization is mildly controlled and the production is stably carried out in the case of applying the reversed-phase suspension polymerization or static polymerization, in a production of a water-absorbent resin.

Abstract: A method for olefin polymerization is provided. A feed stream comprising more than 0.1 ppm by volume of oxygen and 0.3 ppm by volume of water is passed through a first packed bed to selectively remove at least a portion of the oxygen. The feed stream is then passed through a second packed bed to selectively remove at least a portion of the water, providing a purified feed stream comprising less than 0.1 ppm by volume of oxygen and 0.3 ppm by volume of water. Both the first and second packed beds operate at a temperature of from about 0° C. to about 50° C. The purified feed stream is then passed to a polymerization reactor.

Abstract: The present invention relates to a process for polymerizing monomer and comonomer(s) utilizing a bulky ligand transition metal metallocene-type catalyst or catalyst system, where the process is operated in the absence of or with a low amount of any of the isomers of the comonomer(s). The level of these isomers in the process of the invention are eliminated or maintained below a threshold level. It has been discovered that removal of certain isomers of the comonomer used in a polymerization process using metallocene-type catalysts results in an improved process.

Abstract: A diene polymer rubber composition comprising (A) 100 parts by weight of a raw material rubber comprising (A-1) a diene rubbery polymer which is a conjugated diene rubber polymer or conjugated diene-styrene rubbery copolymer (1) containing a modified component in an amount exceeding 60 wt. %, which modified component is obtained by reacting an active end of the rubbery polymer with a polyfunctional compound having, in its molecule, at least two epoxy groups, (2) having a molecular weight distribution Mw/Mn of 1.05 to 3.0, and (3) having weight-average molecular weight of 100,000 to 2,000,000; and based on 100 parts of the component (A), (B) 1–100 parts by weight of rubber extension oil, (C) 25–100 parts by weight of reinforcing silica, and (D) 1.0 to 20 parts by weight in total of a vulcanizing agent and a vulcanizing accelerator.

Abstract: The present invention provides a process for producing a water-absorbent resin of which the residual monomer content and the extractable content are low. The process for producing a water-absorbent resin comprises the step of polymerizing at least one monomer component including acrylic acid and/or its salt as major components to produce a water-absorbent resin that is a neutralized salt, and this process is characterized in that the acrylic acid is a product obtained by catalytic gas phase oxidation of propylene and/or propane and has a protoanemonin content of not more than 10 ppm, and in that the resultant water-absorbent resin has a neutralization ratio of not less than 50 mol %.

Abstract: The present invention provides a diene rubber composition having excellent processability and being improved in both the balance between low rolling resistance and wet skid resistance, and strength properties. The composition according to the invention is a diene polymer rubber composition comprising (A) 100 parts by weight of a raw material rubber comprising (A-1) a diene rubbery polymer which is a conjugated diene rubbery polymer or a conjugated diene-styrene rubbery copolymer (1) containing a modified component in an amount exceeding 60 wt. %, which modified component is obtained by reacting an active end of the rubbery polymer with a polyfunctional compound having, in its molecule thereof, at least two epoxy groups, (2) having a molecular weight distribution Mw/Mn of 1.05 to 3.

Abstract: This invention is directed to a method of removing dimethyl ether from an olefin stream. Dimethyl ether is removed from the olefin stream by first separating the olefin stream into a first stream comprising dimethyl ether and lighter boiling point compounds, and a second stream comprising C4+ olefin and higher boiling point hydrocarbons. The dimethyl ether is then separated from the first stream using extractive distillation.

Abstract: A subject-matter of the present invention is a process for the preparation of a latex by radical aqueous emulsion polymerization in the presence of at least one ethylenically unsaturated monomer, of at least one radical polymerization initiator and of at least one surface-active block copolymer comprising at least one hydrophilic block and at least one hydrophobic block which is prepared by a “living” or “controlled” preparation process, the said copolymer exhibiting a number-average molecular mass of between 2 000 and 20 000, preferably between 4 000 and 16 000, a glass transition temperature of the hydrophobic block of less than 30° C., preferably of less than 25° C., and greater than −100° C., and a surface tension of less than 60 millinewtons per metre (mN/m), preferably of less than 50 mN/m, measured at a concentration in demineralized water of less than or equal to 10−4 mol/l at 20° C.

Abstract: Disclosed is a method of purifying olefin containing oxygenate contaminants. The method incorporates the use of extractive distillation. Under the appropriate conditions, olefins containing very low levels of oxygenate contaminants can be recovered.

Abstract: Disclosed is a method of purifying olefin containing oxygenate contaminants. The method incorporates the use of extractive distillation. Under the appropriate conditions, olefins containing very low levels of oxygenate contaminants can be recovered.

Abstract: Disclosed is a process which comprises (a) reacting allyl bromide with diethyl amine in a molar ratio of at least about 1 mole of allyl bromide per about 1.15 moles of diethyl amine and in a molar ratio of no more than about 1 mole of allyl bromide per about 2 moles of diethyl amine, thereby generating allyl diethyl amine in a monomer reaction mixture; (b) subsequently filtering the monomer reaction mixture to remove impurities; (c) subsequently reacting the allyl diethyl amine with allyl bromide, thereby generating solid diallyl diethyl ammonium bromide; (d) subsequently isolating the solid diallyl diethyl ammonium bromide; (e) subsequently dissolving the diallyl diethyl ammonium bromide in a solvent and adding thereto a polymerization initiator to form a polymerization reaction mixture; (f) subsequently heating the polymerization reaction mixture in a vessel equipped with a reflux condenser to a temperature of from about 90 to about 100° C.

Abstract: In a packed column handling an easily polymerizing substance, the packing with which the column is stuffed is subjected to a water-repelling treatment or a wetting treatment to prevent the easily polymerizing substance in the packed column from polymerizing. By preventing the occurrence of a polymer, it is made possible to ensure continuous production of an easily polymerizing substance-containing solution and decrease the content of the easily polymerizing substance in the product and consequently improve the quality of the product.

Abstract: The invention relates to a process for the production of polyolefins in a reactor system which comprises at least one gas-phase reactor with at least one monomer is polymerized. According to the process, there is fed into the gas-phase reactor the monomer to be polymerized and possibly a polymer-containing fluid. According to the invention, before being fed into the gas-phase reactor, the fluid is subjected to a phase change in order to separate uncondensed compounds from liquid and possibly solid compounds. The gas including the uncondensed compound is recovered, and hydrogen is separated from the gas by membrane separation. The invention can be applied to the removal of hydrogen from the circulation gas of a gas-phase reactor, for example in order to change the polyolefin grade to be produced.

Abstract: The invention provides a hydrophilic resin and an absorbent article, both of which display still less coloring and discoloring when preserved for a long time. The hydrophilic resin is any one of: 1) a hydrophilic resin, obtained by a process including the step of polymerizing a monomer component including a major proportion of either one or both of acrylic acid and its salt which merely have a content of at most 0.20 ppm in total of hydroquinone and benzoquinone; 2) a hydrophilic resin, comprising a major proportion of an acrylic polymer and a minor proportion of either one or both of hydroquinone and benzoquinone, with the hydrophilic resin further comprising a quinhydronation inhibitor of 10˜1,000,000 times the total weight of hydroquinone and benzoquinone; 3) a hydrophilic resin, comprising a major proportion of an acrylic polymer and merely having a coloring degree (YI) of at most 20 after being left under conditions of the open system, 70° C.

Abstract: Petroleum resins are produced by using a supported halide based Lewis acid polymerization catalyst wherein the Lewis acid is chemically bound to the support and free hydrogen halide and/or alkane formed by the reaction of the Lewis acid with the support has been removed. The more active catalysts are useful with both pure monomer and mixed feeds.

Abstract: The present invention provides pure, storage stable, reactive esters of 2-cyanopenta-2,4-dienoic acid and the adhesives and polymers thereof. The monomers of the present invention have the formula: where R is alkyl, alkenyl, alkynyl, alkoxyalkyl, alkenyloxyalkyl, alkynyloxyalkyl, poly(oxyalkyl), aryl, cycloalkyl or a heterocyclyc radical. R may also be one of the foregoing moieties substituted with one or more of the other moieties; this includes the case of the substituent itself being substituted, and may also contain halogens. The reactive monomers of the present invention can be formulated into adhesives by incorporating certain modifiers and additives such as polymeric thickeners, viscocity regulators, plasticizers, thixotrophic agents, compatibilizers, adhesion promoters, pigments and colorants, fillers, deodorants and perfumes. They can also be used in composition with other monomers containing a reactive double bond such as for example cyanoacrylates.

Abstract: In the operation of a gas phase polymerization reactor, a significant amount of production time and material can be lost during the transition from initial process conditions for the production of one product to the desired process conditions for the production of a second product. The present invention recognizes the synergy between the use of a membrane separation zone selective for the removal of hydrogen from the reactor effluent and the operation of the polymerization reactor during the transition period to significantly reduce the transition time and substantially reduce the production of off-specification product during the transition period.

Abstract: There is provided a process for efficiently and economically producing a polymer which is superior in transmittances of visible light and far-ultraviolet light, has a high molecular weight and is light-colored. A process for producing a light-colored vinylphenol-based polymer by subjecting p-vinylphenol to homopolymerization or subjecting p-vinylphenol and a vinyl compound copolymerizable with p-vinylphenol to copolymerization, in the presence of a cationic polymerization catalyst or a radical polymerization initiator, which process comprises subjecting a p-vinylphenol-containing raw material to vacuum flash distillation in the presence of a phenolic compound having no unsaturated side chain and water and subjecting the resulting p-vinylphenol-containing fraction to polymerization.

Abstract: The invention provides a method for purification of an .alpha.-olefin selected from ethylene and propylene for polymerization use which comprises contacting the .alpha.-olefin with an alkali metal carried on a support material. The invention further provides a method for production of a poly-.alpha.-olefin which comprises polymerizing the thus purified .alpha.-olefin in the presence of a polymerization catalyst comprising a transition metal catalyst component and an organometallic catalyst component.

Abstract: The present invention is directed to precipitation polymerization processes for the manufacture of polymers prepared from N-vinyl formamide monomer, the processes including the steps of contacting the N-vinyl formamide monomer with a polymerization medium containing t-butanol as diluent and a free-radical initiator, under conditions effective to polymerize the N-vinyl formamide monomer, thereby forming a precipitate of the polymer in the polymerization medium, substantially isolating the precipitated polymer from the polymerization medium, contacting the substantially isolated polymer with a wash containing a different diluent than the t-butanol used in the polymerization and isolating the washed polymer from the wash.

Abstract: The present invention relates to a process for preparing isobutene-cyclodiene copolymers having a number-average molecular weight of at least 100,000 and an unsaturation of 1.about.30% by mol, characterized in that polymerization is carried out without gelation by reacting 75.about.99.5% by weight of an isobutene and 0.5.about.25% by weight of a cyclodiene or a mixture of cyclodiene as reaction materials, in a polar reaction solvent of 1.about.10 times by weight with respect to the reaction materials, wherein a catalyst solution of 0.02.about.2% by weight in the polar solvent is used in the amount of 0.2.about.2 times by weight with respect to the reaction materials, at a reaction temperature of -100.degree..about.-85.degree. C., thereby obtaining a copolymer, and then removing the residual catalyst activity at a temperature of -100.degree..about.-25.degree. C.

Abstract: Processes are disclosed for the selective hydrolysis of saturated esters, e.g., ethyl propionate, over unsaturated esters, e.g., ethyl acrylate, using enzymes, e.g., lipases. The processes are useful, for example, for removing undesired esters from monomer feeds used in latex polymerization and from the latexes after polymerization. The processes can be used, for example, to treat latexes used in hair fixative compositions to remove unpleasant odors.

Abstract: Purifying reagent for the purification of starting materials to be used in a metal compound catalyzed polymerization, containing proton donating reactive contaminants, consisting of a solid product, obtainable by the metallation of a product of a nucleophilic displacement reaction between a halogen alkylated crosslinked poly(vinlyaromatic) resin and a metallated conjugated diene compound, which product is insoluble inorganic solvents, which is not able to initiate anionic polymerization of olefins or dienes and which is able to scavenge proton donating contaminants, which may hamper polymerizations catalysted by metal organic compounds; and process for purification of starting materials applying said purifying reagent.

Abstract: This invention relates to a method of producing polyisobutenes from a feedstock comprising a mixture of C4 hydrocarbons and containing isobutene and at least 5% by weight of 1-butene using a cationic polymerisation catalyst, characterised in that prior to polymerisation, the feedstock is subjected to a pre-treatment step in order to reduce the 1-butene content thereof to a level which is at least 20% lower than that of the 1-butene content in the initial mixed C4 hydrocarbon feedstock prior to the pre-treatment thereof and the polyisobutene so formed is (a) very high in its vinylidene group content and (b) substantially free of halogen.

Abstract: There is disclosed a process for producing a syndiotactic polystyrene (SPS) which comprises polymerizing a styrenic monomer having a content of indene-based compounds of at most 50 ppm by bringing a polymerization catalyst into contact with the above styrenic monomer, which catalyst preferably comprises an (A) transition metal compound (e.g. Ti compound) and (B) an (a) compound capable of reacting with the above transition metal compound (component (A)) to form an ionic complex (e.g. DMAB) or a (b) oxygen atom-containing compound (e.g. MAO), and optionally a (C) alkyl group-containing metallic compound (e.g. TIBA). By virtue of using the above styrenic monomer, the process enables to minimize the amount of the residual metals in the resultant styrenic polymer without deterioration of the catalytic activity, simplify the process and thereby curtail the production cost of SPS.

Abstract: A process for forming dielectric particles includes admixing a vinyl halide monomer and a crosslinker in a liquid dispersion medium to form a first mixture. A second mixture of an initiator and a stabilizer is prepared and added to the first mixture to form a third mixture in which the monomer polymerizes to form white crystalline polymer particles which are sonified for uniformity. The particles may be stained by exposure to a dehydrohalegenation reagent and dispersed in an electrophoretic fluid for use in an electrophoretic display.

Abstract: A process for processing a cracked feed stream so as to provide a feed stream, having a requisite concentration of isobutylene and butene-1, to a polymerization unit for polymerization of isobutylene.

Abstract: A process is disclosed for the preparation of liquid and aqueous solutions of amorphous colorless poly (vinyl methyl ether) polymer with low level of impurities from purified vinyl methyl ether. The polymer has relatively high molecular weight, narrow molecular weight distribution and does not degrade readily due to the presence of impurities. The purification of the monomer uses a procedure selected from the group consisting of a vapor-liquid separation, a solid-liquid separation and combinations thereof to remove the impurities at a temperature within the range of from -20.degree. C. to +30.degree. C. The aqueous solution is prepared by devolitilization of solvent solutions of the polymerized purified vinyl methyl ether monomer. The solid polymer is prepared by heating the aqueous solution of the poly(vinyl methyl ether). The amorphous polymers of poly(vinyl methyl ether) are particularly suited for adhesive applications.

Abstract: A highly polymerizable dicyclopentadiene (DCPD) monomer composition is obtained. The dicyclopentadiene so obtained is highly suitable for ring-opening polymerization by metathesis catalysts. The active DCPD yields articles with excellent physical properties upon in-mold polymerization.

Abstract: A method for the selective separation of a particular compound from a mixture of compounds, by enzymatically converting a weakly adsorbable compound to a strongly adsorbable compound, and binding the converted compound to a material of appropriate chemical properties is described. Also described are methods for removing contaminants from wastewater streams, and from intermediate chemical process streams.

Abstract: A process and plant are disclosed for the manufacture of particulate or liquid elastomeric polymers suitable for the manufacture of a wide variety of commercial elastomers, substantially in the absence of water for purifying and particulating the elastomer.

Abstract: Polyolefins are produced by a process which includes the steps of: polymerizing an olefin in a reaction zone; removing unreacted olefin from the polymer in a flash chamber and recycling the unreacted olefin to the reaction zone; stripping unreacted olefin from the polymer by passing a stripping gas through the polymer in a stripping zone; passing the unreacted olefin from the stripping zone at superatmospheric pressure through an adsorbent which selectively adsorbs olefins; depressurizing the adsorbent to produce a substantially pure olefin and recycling the substantially pure olefin to the reaction zone; purging the adsorbent bed with a nonadsorbable gas to remove residual unreacted olefin from the adsorbent; and passing the purge gas-unreacted olefin to the stripping zone to be used as stripping gas.

Abstract: This invention relates to a two component catalyst system for the polymerization of metathesis polymerizable cycloolefins, comprising (a) a tungsten compound of the formula WOX.sub.4-x (OAr).sub.x where X is chlorine, bromine or fluorine, Ar is a hindered phenyl ring having 1-5 specified substituents and x = 1, 2 or 3; and (b) an activator compound.Among the preferred molecules or groups that are substituted on the phenyl ring of the tungsten compound are phenyl, chlorine, bromine, methoxy and isopropyl groups. Ar can also represent a multi-substituted phenyl group such as 2,4-dichloro-6-methylphenyl.

Abstract: Cyclic olefin metathesis polymerization catalyst comprising metal compounds wherein said metals consist essentially of a minor amount of a transition metal which Will initiate ring-opening metathesis polymerization of a cyclic olefin and a major amount of at least one second metal which will propagate the polymerization, wherein said catalyst is essentially devoid of pyrophoric metal compounds, e.g. metal alkyls, and preformed metal carbenes. A preferred transition metal is ruthenium. Said second metal can comprise aluminum, copper, hafnium, iron (III), iridium, manganese, molybdenum, nickel, niobium, rhenium, rhodium, tantalum, titanium, tungsten, yttrium, a Lanthanide, zinc or zirconium or a mixture thereof. Using such catalyst cyclic olefin, e.g. norbornene derivatives, can be polymerized, e.g. in an extruder, even in the presence of water.

Abstract: Highly crystalline high melting 1,5-hexadiene cyclopolymers are prepared by carrying out the polymerization in the presence of a catalyst comprising a specific Zr or Hf metallocene compound and specific alumoxane compounds.

Abstract: Methods and apparatus are disclosed for removing undesirable volatile components having high boiling points from a product stream during polymerization of monovinyl aromatic compounds such as styrene, which methods include the use of partial condensers, devolatilizers, and filter beds.

Abstract: The dimer content in alpha, beta- ethylenically unsaturated ketones may be reduced by treating the ketone with a peroxide of the formula ##STR1## wherein R.sub.4 is a C.sub.1-6 branched or straight chain alkyl radical or a C.sub.6-10 aromatic radical and n is 1 or 2. The treated ketone has a faster rate of polymerization with other ethylenically unsaturated monomers.

Abstract: A copolymer of maleic anhydride and an alkyl vinyl ether is prepared with substantially reduced benzene content by first contacting the alkyl vinyl ether with activated charcoal and then reacting together the charcoal treated alkyl vinyl ether and maleic anhydride in the presence of a free radical initiator.

Abstract: A free-radical retrograde polymerization process for forming a polymer. An admixture of reactants including predetermined amounts of a monomer, a solvent, and a free-radical-initiator is reacted. A precipitation polymerization reaction occurs such that a polymer-rich phase is at a temperature generally above the lower critical solution temperature (LCST) of the admixture.

Abstract: Novel polymerized dienes prepared by the step propagation, condensation type polymerization of acyclic dienes employing Lewis acid-free metal alkylidene complexes as catalysts.

Abstract: A process for blanking a reaction mixture utilizing as a blanking agent a difunctional lithium composition.

Abstract: A process for preparing improved yields of styrene polymers by means of polymerization with a Ziegler-Natta type polymerization catalyst wherein the styrene monomer is first contacted with a hydrogenating agent under hydrogenation conditions such that substantially all phenylacetylene contained in the monomer stream is hydrogenated and thereafter contacting with a Ziegler-Natta catalyst.

Abstract: A process is disclosed for preparing a blend of a metathesis polymer and a radical polymer wherein a norbornene polymer is metathesis polymerized in the presence of a vinyl compound having two double bonds in conjugated relationship. Also included in the system is a compound capable of being reduced to a radical by the reduced valence transition metal element which serves as the catalyst of the metathesis polymerization. Examples of such compounds are specific chlorinated organic and chlorinated inorganic compounds.

Abstract: Narrow molecular weight telechelic and/or block copolymers are prepared by anionic polymerization using an initiator composition comprising a multifunctional lithium initiator in combination with an organic diamine or triamine and optionally a metal alkoxide.

Abstract: Methods of preparing storage stable components useful for metathesis bulk polymerization of cycloolefin monomers are provided. These components contain cycloolefins with norbornene-functional groups and cocatalysts activated with a halometal compound. In these methods, the cocatalyst is completely formed before the halometal activator is added to prevent the formation of unwanted hydrogen halides, which catalyze undesired crosslinking reactions which destabilize the cocatalyst component. Bulk polymerization systems are provided wherein these storage stable cocatalyst components are paired with catalyst components that together form the complete metathesis catalyst system. For some embodiments, storage stability is aided by the removal of water.

Abstract: A process is disclosed for treatment of alkyl methacrylate monomers for subsequent polymerization by an anionic initiator to produce a polymer with a molecular weight distribution between about 1.20 and about 1.01. The process involves treatment of the monomer with an aluminum hydrocarbyl or boron hydrocarbyl in quantities which permit polymerization in the presence of the by-products of the reaction between the impurities and the aluminum hydrocarbyl or boron hydrocarbyl.

Abstract: The specification discloses a monovinylidene aromatic polymer having a molecular weight of at least 50,000 and an extremely narrow molecular weight distribution of less than 1.5, preferably with at least 80% by weight of the polymer having a molecular weight within plus or minus 30% of the weight average molecular weight. This polymer is produced through anionic polymerization of a pure feed stock which is first cooled to a temperature at which an anionic initiator preferentially reacts with impurities present in the feed stock and initiates the polymerization reaction but does not substantially propagate styrene polymerization. The initiator is uniformly dispersed into the feed stock while maintaining it at the lower temperature and the feed stock temperature is subsequently increased to a temperature at which polymerization of the sytrene proceeds normally.

Abstract: Acetylene can be polymerized into a polyacetylene by a solid-state polymerization reaction when it is compressed into a solid under a high pressure of, for example, 1 GPa or higher. The polyacetylene product is obtained in a bulky transparent form in contrast to conventional polyacetylenes in a fibrous form prepared by utilizing a Ziegler-Natta catalyst, and free from impurities because neither catalyst nor solvent is used in the reaction.

Abstract: Control of an anionic polymerization is obtained by monitoring an indicator of molecular weight of the polymer in the polymerizing mixture, measuring the molecular weight of the polymer produced therein and using this information to control the rate at which polymerization initiator is added to the polymerizing mixture in a continuous stirred tank reactor.