Abstract: Process for preparing a pressure-sensitive adhesive composition, characterized in that tackifiers in dispersed, melted or solid form are mixed with natural rubber latex, the water content being not more than 45% by weight.

Abstract: The present invention relates to a continuous process for the production of impact resistance-modified thermoplastics. An elastomer, in particular a particulate graft polymer with a water moisture content of 1 to 50%, preferably 10 to 40%, is incorporated into a thermoplastics melt in a large volume kneader reactor. The mixing ratio of elastomer to thermoplastics melt is 4:1 to 1:4. The energy required to melt the elastomer and to evaporate the adhering water is added by heating the walls of the apparatus and via the kneading action of the installed rotating parts.

Abstract: Described herein is a process and an apparatus for preparing propylene homopolymers and copolymers, which comprises polymerizing propylene optionally with comonomers in the presence of a catalyst at elevated temperature and pressure in at least one slurry reactor and at least one gas phase reactor, the polymerization product of at least one slurry reactor, containing unreacted monomers, being conducted to a first gas phase reactor essentially without recycling of the unreacted monomers to the slurry reactor. The invention provides for fast start-ups because the gas phase bed material is available directly from the loop reactor.

Abstract: A set of trim forward bins is utilized to set aside, distribute and allocate portions of granular product made in a continuous, usually fluidized bed, olefin polymerization reactor, to form blends which more efficiently utilize the products made during transitions from one set of specifications to another and/or to maintain a target property substantially continuously during steady state production of a single product.

Abstract: A process for preparing impact-modified styrene polymers (HIPS) omprises anionic polymerization of styrene in the presence of a rubber in one or more polymerization reactors in succession. The rubber is prepared in solution in an immediately upstream process. The heat of polymerization is utilized to remove the solvent for the rubber, this solvent having a boiling point lower than those of styrene and ethylbenzene, from at least one of the polymerization reactors via distillation with distillative cooling, and the solvent is reintroduced into the process of rubber preparation.

Abstract: A procatalyst and a process for the preparation of a multimodal ethylene homopolymer or copolymer by gas-phase polymerisation is described. The procatalyst used in the process is prepared by: a) contacting the support, preferably silica with a halogenating agent, preferably ethyl aluminium dichloride to obtain a first reaction product, b) contacting the first reaction product with a compound or mixture containing hydrocarbyl and one or more of hydrocarbyloxy, monoalkylamido, dialkylamido, carboxylato and alkoxymethoxy groups linked to magnesium, thereby to obtain a second reaction product (the procatalyst precursor), and c) contacting the second reaction product with a titanium compound, preferably TiCl4. In step a) the molar ratio of the alkyl metal chloride to the surface hydroxyls of the inorganic oxide is preferably between 1:1 and 10:1. In step b) the atomic ratio of the magnesium to the chlorine of the alkyl metal chloride of step a) preferably is between 1:1.5 to 1:2.5.

Abstract: A process is disclosed for enhancing the production of polymerized monovinyl aromatic compounds, in which process a small polymerization reactor is inserted in the recycle stream to deactivate the polymerization inhibitors in the recycle stream and to further increase the conversion level of monomer to desirable polymer.

Abstract: The present invention relates to a continuous process for the production of impact resistance-modified thermoplastics. An elastomer, in particular a particulate graft polymer with a water moisture content of 1 to 50%, preferably 10 to 40%, is incorporated into a thermoplastics melt in a large volume kneader reactor. The mixing ratio of elastomer to thermoplastics melt is 4:1 to 1:4. The energy required to melt the elastomer and to evaporate the adhering water is added by heating the walls of the apparatus and via the kneading action of the installed rotating parts.

Abstract: Abstract of the disclosure: A process is described for the continuous preparation of an impact-resistant molding material by anionic polymerization of styrene or another aromatic vinyl compound or mixtures thereof in the presence of a solvent and a block rubber, wherein the polymerization is carried out in at least 2 reaction vessels that together form a reactor cascade, the monomer stream being subdivided among the reaction vessels present, the living polymer chain ends being terminated in a conventional manner and the solvent being removed.

Abstract: A high quality copolymer of styrene and methyl methacrylate is economically produced by polymerizing styrene and methyl methacrylate in a homogeneous solution of raw materials comprising methyl methacrylate, styrene, and an antioxidant, while the solution of raw materials is continuously supplied to a polymerization reactor including at least one complete-mixing type reaction tank, continuously removing the polymerization product from the polymerization reactor, supplying the polymerization product removed from the polymerization reactor directly to an extruder having a plurality of vents, and extruding a copolymer from the extruder, while volatile matter are removed through the plurality of vents.

Abstract: A method of synthesis for building a polymer chain, oligonucleotides in particular, by sequentially adding monomer units to at least one solid support for growing and immobilizing a polymer chain thereon in a liquid reagent solution. The method includes the step of: A) depositing a liquid reagent in a reaction well (26) in contact with at least one solid support and at least one monomer unit of the polymer chain affixed to the solid support. The well (26) includes at least one orifice (74) extending into the well (26), and is of a size and dimension to form a capillary liquid seal to retain the reagent solution in the well (26) to enable polymer chain growth on the solid support. The method further includes the step of B) expelling the reagent solution from the well (26), while retaining the polymer chain therein.

Abstract: A process comprising contacting ethylene and at least one alpha-olefin comonomer having 3 to 8 carbon atoms with a transition metal based catalyst system in two fluidized bed reactors connected in series, in the gas phase, under polymerization conditions, with the provisos that:(a) the first reactor is operated at a temperature at or above the dew point of the mixture of monomers, but no higher than about 5 degrees C. above said dew point;(b) the mixture of ethylene copolymer matrix and active catalyst formed in the first reactor in the series is transferred to the second reactor in the series;(c) other than the active catalyst referred to in proviso (b), no additional catalyst is introduced into the second reactor;(d) in the reactor in which a low melt index copolymer is made:(1) the alpha-olefin is present in a ratio of about 0.01 to about 0.4 mol of alpha-olefin per mol of ethylene; and(2) optionally, hydrogen is present in a ratio of about 0.001 to about 0.

Abstract: This invention relates to a method for preparing compositions comprising terminally unsaturated polymers of low molecular weight, referred to as oligomers or macromonomers. In particular, a first oligomer composition is obtained by free radical polymerization of a reaction mixture comprising monomers. Terminally unsaturated oligomers in the first oligomer composition, or a selected portion of the composition, are reinitiated into free radicals in order to continue their oligomerization to a desired endpoint. The process is useful for preparing an oligomer composition having a controlled degree of polymerization. The process is also useful for preparing block copolymers. Such oligomer compositions or block polymers are useful for preparing engineered or structured polymers used in making various end products, including plastics, coatings, films, and dispersants.

Abstract: The present invention provides polymer polyols and a method for preparing polymer polyols which have (1) exceptional dispersion stability, especially at high styrene contents, and (2) substantially smaller particle sizes than polymer polyols having equivalent viscosity. In a preferred embodiment of the present invention, a first reaction product is obtained by feeding the following materials to a first continuous reactor in the presence of a free radical initiator or catalyst: (a) less than about 50 wt. % of a total monomer proportion or monomer mixture, preferably comprising styrene/acrylonitrile at a ratio preferably greater than about 50/50 wt. %; (b) at least about 50 wt. % of a total base polyol proportion; (c) a majority of a precursor stabilizer; and, (d) a polymer control agent (PCA).

Abstract: A process for manufacturing bimodal olefin polymers and copolymers having a ratio between low molecular weight fractions within the range of 40:60-70:30, by mixing under shear conditions 5-50 percent by weight of a low molecular weight unimodal polyolefin having a molecular weight (Mw) between 15,000-30,000, and 95-50 percent by weight of a bimodal polyolefin having a ratio between low molecular weight fractions and high molecular weight fractions within the range of 30:70-55:45. According to a preferred embodiment, there is used a multi-phase process including a loop reactor followed by a gas-phase reactor, wherein a part of the product coming out from the loop reactor is separated and combined with the bimodal product coming out from the gas-phase reactor.

Abstract: The present invention provides polymer polyols and a method for preparing polymer polyols which have (1) exceptional dispersion stability, especially at high styrene contents, and (2) substantially smaller particle sizes than polymer polyols having equivalent viscosity. In a preferred embodiment of the present invention, a first reaction product is obtained by feeding the following materials to a first continuous reactor in the presence of a free radical initiator or catalyst: (a) less than about 50 wt % of a total monomer proportion or monomer mixture, preferably comprising styrene/acrylonitrile at a ratio preferably greater than about 50/50 wt %; (b) at least about 50 wt % of a total base polyol proportion; (c) a majority of a precursor stabilizer; and, (d) a polymer control agent (PCA).

Abstract: An impact resistant styrene resin is prepared by the continuous bulk polymerization of a styrene monomer in the presence of a second component having a 5 wt % styrene solution viscosity which may be polybutadiene, styrene-butadiene copolymerization rubber, or mixtures thereof. Preliminary polymerization is carried out in a reactor having a dynamic mixing structure and which is integrated between and connected to the material feed line and the initial-stage polymerization line.

Abstract: A process for making a blend of high-density polyethylene polymers containing one or more C3 to C12 .alpha.-olefin comonomers. The process begins in two parallel streams. In one stream ethylene is polymerized alone, and in the second stream ethylene is polymerized with the comonomer(s). The two streams are combined in a subsequent reactor where the polymerization process is completed. The polymerization produces a polymer wherein the comonomer is concentrated in the higher molecular weight fractions.

Abstract: A first reactor is used to graft polystyrene to a rubber-like polymer. A second reactor is used to obtain a mixture of styrene and polystyrene. The effluent from both the first and the second reactors are fed into a quiescent reaction zone where phase inversion occurs. The phase inverted material is fed into post inversion reactors to substantially complete the polymerization of the styrene monomer, and any unreacted styrene monomer is driven off to form the improved high-impact polystyrene.

Abstract: Process for the continuous bulk production of high impact vinylaromatic copolymers in which the vinylaromatic monomer, and if present, a comonomer selected from the group consisting of acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid and their alkyl- or cyclo-alkyl-esters containing from 1 to 8 carbon atoms in the alkyl group, the rubber, a part of the diluent solvent and the catalyst are premixed in a premixer at a temperature under 100.degree. C. and fed to a plug-flow agitated tubular reactor, which is divided into several stages or zones. The excess mixture is recycled to the premixer and the remaining part of the diluent solvent is injected into the top of the reactor to prevent the formation of incrustations. In the first zone of the reactor, the temperature and the residence time of the mixture are regulated so to have the halving the catalyst life.

Abstract: In the gas phase, two stage process for the production of polypropylene impact copolymer, the fouling of the second stage recycle loop and the heat exchange unit incorporated therein is reduced by the addition to the substantially gaseous material passing through the loop of a small amount of alkylene compound selected from alkylene glycol compounds, alkylene glycol derivatives of alkylene diamines or ethers or esters thereof.

Abstract: In a process for producing a high impact styrene resin by continuously polymerizing a styrene monomer in bulk in the presence of a rubbery polymer, the improvement whereina polymerization line is used which is comprised of an initial-stage polymerization line (II) following a material feed line (I) and consisting of one or more tubular reactors having fixedly set therein a plurality of mixing elements having no moving parts, a main polymerization line (III) following the initial-stage polymerization line (II) and consisting of one or more tubular reactors having fixedly set therein a plurality of mixing elements having no moving parts, and a recycle line (IV) which branches between the initial-stage polymerization line (II) and the main polymerization line (III) and returns to the initial-stage polymerization line (II), anda minor part or a major part of a flow of the initial-stage polymer solution leaving the initial-stage polymerization line (II) is recycled through the recycle line (IV) while the remaining

Abstract: Process for the continuous production in solution of styrene thermoplastic resins by polymerization of a vinyl-aromatic monomer and of a vinyl-nitrile monomer in the presence of an elastomer and of a starter, wherein polymerization is conducted in two or more steps, wherein the elastomeric component is fed, in solution in the solvent and/or in the monomers, to the first step, polymerization is carried out in the subsequent steps at temperatures ranging from 70.degree. to 150.degree. C., in each step the reaction mass is gently and homogeneously stirred and the reaction product is caused to flow to a thin evaporator heated at 150.degree.-300.degree. C.

Abstract: Water-dilutable printing ink binder system based on a binder in the form of a clear, dilute, ammoniacal or amine-containing solution, the binder being a product of reacting a natural resin acid and formaldhyde in at least one stage, the amount of (100% strength) formaldehyde being 1 to 25% by weight, based on the natural resin acid, and the reaction having been carried out under atmospheric or superatmospheric pressure in the absence or in the presence of 0.1 to 2% by weight of a lewis catalyst. A variant comprises partially esterifying the natural resin acid/formaldehyde reaction product with at least one polycarboxylic acid unit of the group (a) an ethylenically unsaturated dicarboxylic acid and/or the anhydride thereof and (b) a hydroxycarboxylic acid. The binder system has added to it as solubilizers monohydric and/or polyhydric alcohols, and the pH value is preferably set to 7.5 to 10.

Abstract: A continuous process for the production of high impact polystyrene using a free radical initiator which decomposes to form only non-acid decomposition by-products.

Abstract: A continuous flow process for the production of high impact polystyrene, wherein specific types of polymerization inhibiting impurities are removed from a recycle stream prior to feeding or introducing the recycle stream into a styrene polymerization zone. Preferably, the process further comprises the step of monitoring the acidity of the recycle stream.

Abstract: Water setting paper (high water-absorbency material) comprised of pulp fiber, water-soluble resin and high wate-absorbency resin is produced in sheet form for use in urine containers or portable toilets. Water setting paper or the high water-absorbency sheet thus formed absorbs and solidifies the urine, allowing the urine to be disposed of easily, rapidly and hygienically.

Abstract: Polyacetal obtained by the polymerization of trioxane, for example, suspended in an organic solvent, in the presence of a comonomer (for example, ethylene oxide), is stabilized by hydrolysis in the heated state under pressure and then, after hydrolysis, the reaction mixture is depressurized to atmospheric pressure in order to release an aqueous phase containing the polymer and a vapor phase which contains formaldehyde and trioxane. According to the invention, the latter is recycled directly into the formaldehyde trimerization stage under reduced pressure.

Abstract: Process for the preparation of thermoplastic copolymers of .alpha.-methylstyrene and acrylonitrile by continuous bulk copolymerization ofA. 30 to 50 mol % of .alpha.-methylstyrene andB. 70 to 50 mol % of acrylonitrileat temperatures from 60.degree. to 120.degree. C. with average residence times of 4 to 12 hours in the presence of initiators which supply free radicals, carried out in at least two continuously operated mixed tank reactors, characterized in that 100 molar parts of a monomer mixture ofA.sub.0. 34 to 52 mol % of .alpha.-methylstyrene andB.sub.0. 66 to 48 mol % of acrylonitrileare fed continuously into the first tank reactor per unit time, and, with back-mixing, are copolymerized up to a conversion of 5 to 30 molar parts to give a copolymer of the compositionA.sub.1. 49 to 53 mol % of .alpha.-methylstyrene andB.sub.1. 51 to 47 mol % of acrylonitrile,and the mixture consisting of 70 to 95 molar parts of the monomers A and B and 5 to 30 molar parts of the copolymer of the composition A.sub.1 -B.sub.

Abstract: Water-dilutable printing ink binder system based on a binder in the form of a clear, dilute, ammoniacal or amine-containing solution, the binder being a product of reacting a natural resin acid and formaldehyde in at least one stage, the amount of (100% strength) formaldehyde being 1 to 25% by weight, based on the natural resin acid, and the reaction having been carried out under atmospheric or superatmospheric pressure in the absence or in the presence of 0.1 to 2% by weight of a Lewis catalyst. A variant comprises partially esterifying the natural resin acid/formaldehyde reaction product with at least one polycarboxylic acid unit of the group (a) an ethylenically unsaturated dicarboxylic acid and/or the anhydride thereof and (b) a hydroxycarboxylic acid. The binder system has added to it as solubilizers monohydric and/or polyhydric alcohols, and the pH value is preferably set to 7.5 to 10.

Abstract: In a copolymerization process of propylene, a mixture of unreacted propylene and ethylene is recovered. It is then fed to a distillation system which includes first and second distillation columns. The distillation system is operated in such a way that the temperature and pressure of the top of the second distillation column remain constant and an ethylene-propylene mixture can be recovered at a constant ethylene/propylene ratio from the top of the second distillation column. By using the thus-recovered ethylene-propylene mixture, the copolymerization reaction can be carried out under excellent control so that the ethylene-propylene copolymer can be obtained with uniform quality and properties.

Abstract: Halogenated hydrocarbons are removed from hydrocarbon solvents for reuse in a butyl rubber process by contacting the halide containing hydrocarbon solvent with alumina at a temperature of at least 20.degree. C. In particular 2-methyl-3-chloropropene-1, 2-methyl-1,2-dibromo-3-chloropropane and tribromo isobutane or mixtures thereof can be removed from a hydrocarbon solvent by the process of this invention. The halide removal is preferably carried out at a temperature of at least 40.degree. C., e.g., 60.degree. C. to 100.degree. C.

Abstract: The present invention relates to a process for producing a polypropylene-ethylene block copolymer by a continuous multi-stage polymerization comprising a first stage in which polypropylene is polymerized in a first polymerization vessel in the presence of a propylene polymerization catalyst, and a second stage in which propylene and ethylene are copolymerized in a second polymerization vessel, wherein the polypropylene slurry discharged from the first polymerization vessel is supplied to a concentrator to separate said slurry into a concentrated polypropylene slurry and a supernatant liquid, the concentrated polypropylene slurry is then introduced through an upper part of a hydraulic sedimentation classifier to be contacted with a countercurrent of the upward flowing of the supernatant fluid introduced through a lower part of said classifier to obtain hydraulically sedimented polypropylene, and non-hydraulically sedimented polypropylene; the thus obtained hydraulically-sedimented polypropylene is then supplie

Abstract: Molding materials containing high molecular weight polyphenylene ethers are produced by a process in which a solution of a polyphenylene ether in an organic solvent, together with another polymer, is freed of solvent by multi-stage evaporation.The solvent is preferably an aromatic compound from the class comprising the hydrocarbons, halohydrocarbons, ethers or esters, the ratio of the other polymer to the polyphenylene ether is advantageously from 99:1 to 20:80 parts by weight, the other polymer is, in particular, a homopolymer or copolymer of styrene or of a homolog thereof, which may be modified with rubber, and the multi-stage evaporation process preferably comprises not less than two and not more than four working up stages.The evaporation is carried out in general at from 120.degree. to 280.degree. C. and under a pressure of from 1 to 3,000 mbar, advantageously in the presence of assistants which reduce the partial pressure, eg. water and/or methanol.

Abstract: The invention relates to a process for preparing ABS polyblends having small and large grafted rubber particles dispersed therein providing polyblends having greater toughness and chemical resistance. The process includes extracting small grafted rubber particles into a separated monomer phase which is mass polymerized to a first melt, mixing said first melt with a second melt having present larger grafted rubber particles to form a third melt which is devolatilized to an ABS polyblend having a bimodal grafted rubber particle size distribution.

Abstract: A process and apparatus for preparing vinyl polymers by continuous bulk or solution polymerization provide improved mixing during polymerization. In the process, fresh polymerization starting material is incorporated into a part of reaction mixture withdrawn from a polymerization zone and then fed to the polymerization zone. Polymerization temperature is kept at 100.degree. to 200.degree. C. and polymer content in a reaction mixture withdrawn from the polymerization zone is kept at 50 to 80% by weight. A tank having agitating means, outlet opening and recycling inlet is used as polymerization reactor. Said recycling inlet is preferably located at a position corresponding to 1/4 or less of the total height from the bottom to the top of the tank.

Abstract: Anion exchange resins produced by reacting a stabilized polychloromethylstyrene polymer bead with a polyamine containing at least two tertiary amine groups of which at least one is a terminal group, and processes for producing the resins in uniform sizes.

Abstract: The process relates to a continuous mass polymerization process for ABS polyblends wherein a monomer formulation of monoalkenyl aromatic and alkenyl nitrile monomers having a conjugated diene rubber dissolved therein is continuously charged to a first, stirred reaction zone operating at a steady conversion of said monomers of about 5 to 45% forming a partially polymerized first mixture having said rubber dispersed as grafted rubber particles, followed by continuously polymerizing said first mixture in a second stirred reaction zone by substantial linear flow polymerization under evaporative cooling of said monomers to a second partially polymerized mixture containing about 50 to 90% of ABS polyblend solids and separating said solids from said second mixture as an ABS polyblend.

Abstract: In the solution polymerization process wherein monomers comprising at least one conjugated diene are polymerized followed by coupling with a polyfunctional coupling agent which results in some alkyl chloride formation and solvent recovered from said polymerization is used in a subsequent solution polymerization process, the improvement comprising contacting said solvent with a molecular sieve to remove alkyl chloride therefrom before said solvent is used in said subsequent polymerization.