Abstract: A process is disclosed for the preparation of reactive copolymers by bulk- or solution polymerizing a material composed of a monomeric mixture consisting of at least one glycidyl group-containing monomer and at least one monomer copolymerizable therewith and a chain transfer agent in a stirred-tank reactor, and withdrawing from the reactor a liquid which contains the reactive copolymer in an amount equal to the feed. The process is improved by removing from the reaction liquid together with the reactive copolymer the adduct formed in the liquid by the reaction of the chain transfer agent with the monomers. The residue is then liquefied and directly recycled to the reactor.

Abstract: Removing water and light ends from recycle liquid olefin monomer and fresh liquid olefin monomer feed before catalytic polymerization thereof in said liquid state with a water sensitive catalyst, by flowing them through a mass transfer plate tower with a reboiler which vaporizes them upwardly through openings in the plates of said tower and in the form of bubbles through layers of liquid monomer reflux maintained on said plates by weirs and downcomers by means of which said reflux is flowed from each plate downwardly to the plate below it and, as a layer, along the top of the plate and thence downwardly to the next lower plate, condensing in a reflux condenser the vapor from the top of said tower, removing from said condenser as a vapor said light ends, removing water from said condenser as a heavy condensed liquid fraction and refluxing back to the top of said tower as a lighter liquid fraction, condensed liquid monomer. Preferably the tower is a valve tray tower and the plates are valve trays.

Abstract: Removing oligomers (short chain polymers of from two to seven atoms in the chain) from olefin monomer vapor recovered for recycle from the reaction mass resulting from the catalytic polymerization of liquid olefinic monomers by flowing such recovered vapor through a mass transfer plate tower upwardly through openings in the plates of said tower and in the form of bubbles through layers of liquid oligomer reflux maintained on said plates by weirs and downcomers by means of which said reflux is flowed from each plate downwardly to the plate below it and, as a layer, along the top of the plate and thence downwardly to the next lower plate, condensing in a reflux condenser the vapor from the top of said tower, removing olefin monomer from said condenser as a vapor and refluxing condensed liquid oligomers back to the top of said tower. Preferably the tower is a valve tray tower and the plates are valve trays.

Abstract: A method which comprises drawing a part of the reaction liquid from a reactor for unsaturated polyesters, bringing the drawn liquid into contact and reaction with a gaseous starting material or a liquid starting material capable of being converted into vapor on reaction, for example, an alkylene oxide by means of tubular mixing and recycling this reaction liquid to the reactor thereby preventing increase in pressure of the reactor. An apparatus which comprises a reactor having a confined or open structure, a tubular mixer where a part of the reaction liquid drawn from the reactor is mixed with a gaseous starting material or a liquid starting material capable of being converted into vapor on reaction, which is blown through a nozzle, to cause a vapor-liquid reaction, and a liquid circulation pump for supplying the liquid drawn from the reactor to the tubular mixer and recycling the vapor-liquid reaction product to the reactor.

Abstract: Acrylonitrile or monomer mixtures containing acrylonitrile are purified by treating them with alkaline reacting compounds followed by distillation. The products are particularly suitable for the manufacture of acrylonitrile polymers showing improved color stability.

Abstract: Gaseous and/or vaporous monomers are recovered from reaction off-gases by treating the latter with compounds which are liquid at 50.degree. C and atmospheric pressure and with which, and/or in which, the said monomers are subsequently reacted.

Abstract: A process for cooling a polymerization reaction of compounds in a dispersion and/or solution involves evaporation of one or more liquids contained in the dispersion and/or solution, condensation of the vapors in a reflux condenser, and recycling of the thus-condensed vapors into the reactor, together with the use of a controllable flow of coolant which is introduced into the reflux condenser jacket. In this process the amount of heat given off during condensation serves as the control variable for a controller for controlling the input of cooling medium for the reflux condenser.

Abstract: The fouling of autorefrigeration polymerization systems because of entrained particles in the vaporized solvent-diluent is substantially reduced by returning the recycle solvent-diluent into the reaction zone through nozzles which provide a solvent-diluent spray of an average droplet size of less than 1000 microns, preferably between about 225 and 300 micron average particle size, which spray removes major amounts of entrained particles down to 5 microns in size. The solvent diluent may be an inert material or unreacted alpha-olefin, such as propylene.

Abstract: Improved process permitting a vinyl chloride batch which is to undergo polymerization in suspension, to be additionally cooled. Gaseous matter formed in the gas chamber of a polymerization vessel is delivered through a pipe connection communicating with the gas chamber and a reflux condenser, to the reflux condenser and condensed therein, and the resulting condensate is returned to the polymerization vessel. In the improved process one or more nozzle structures are used to inject fully desalted water into the pipe connection over the entire polymerization period. The spray water has an approximate temperature of from 5.degree. to 45.degree. C and is used in a proportion of at least 10% by volume, based on the overall quantity of water necessary for effecting the polymerization.

Abstract: The dry polymerization of olefins to produce polymers having a molecular weight above 50,000 in the presence of a catalyst system formed of a compound of a transition metal and a co-catalyst of an organo-metallic compound of a metal of Groups II or III of the periodic table, in which the polymerization reaction is carried out in a series of reaction vessels wherein the formed polymer is transferred from one to the other and in which additional co-catalyst is added to reaction vessels beyond the first, the gaseous effluent from each reaction vessel is recycled back to the reaction vessel and in which the co-catalyst is introduced into the first reaction vessel in an amount such that the atomic ratio of the metal of the co-catalyst to the transition metal is within the range of 0.1 to 10, and in which the co-catalyst is introduced into vessels other than the first in an amount such that the atomic ratio of metal of the co-catalyst to the transition metal is within the range of 0.1 to 20.

Abstract: A process for the polymerization of aromatic vinyl compounds and their copolymerization with alkyl esters or nitriles of acrylic and/or methacrylic acid, wherein1. in a first stage, the monomer or monomers is or are continuously introduced at excess pressure into a first reaction zone and polymerized there to a degree of conversion of 5 - 40% by weight at a temperature of from 80.degree. to 170.degree. C;2. in a second stage, the reaction mixture is conducted at constant pressure into a second reaction zone designed for conducting highly viscous melts, the mixture flowing through this reaction zone at a rate which is 1.1 to 5 times the intrinsic rate, and polymerized there to a degree of conversion of 40 to 95% at temperatures of from 120.degree. to 250.degree. C, the excess pressure in the first and second stage being chosen so that the monomer or monomers is or are liquid, and the polymer is continuously removed from this zone with release of the pressure; and3.

Abstract: The method of this invention is particularly useful for removing heat from an exothermic reaction of a liquid medium. An example of such a reaction is an emulsion polymerization of styrene and butadiene to obtain a latex product. In this reaction the butadiene will boil at the temperature and pressure conditions in the reactor. Attached to the reactor is a condenser unit, which is basically a modified shell and tube heat exchanger. During the reaction the butadiene vapors are directed from the reactor into the tube bundle of the condenser unit through the top of the unit. In the condenser the butadiene vapors are condensed to a liquid, which flows downwardly into the reactor to cool the reaction mass.

Abstract: An improved method of removing heat from polymerization reactions of normally gaseous monomers in the gas phase comprising feeding the monomer in liquid form to a polymerization zone, immediately after entering said zone, removing a portion of said gaseous monomer from the polymerization zone, liquefying said portion of monomer by cooling it at the same pressure as that prevailing in the polymerization zone, recycling the liquefied monomer to the polymerization zone together with fresh monomer in liquid form and causing said liquid monomer to change to the gaseous form immediately after entering said zone. The improvement consists in not only condensing the monomer outside the polymerization zone but also storing the same, in keeping the temperature in the polymerization zone constant by regulating the rate at which liquid monomer is fed to the zone, and in keeping the temperature and pressure in the polymerization zone within limits conducive to the gaseous state of the monomer.

Abstract: A fluid bed reactor system and process employing a silyl chromate catalyst therein wherein the reactor system comprises a vertical reactor having a fluidizing medium permeable distribution plate towards the base thereof, a fluidizing medium supply line to supply fluidizing medium to the base of the reactor, a catalyst injection means to supply particulate catalyst to the side of the reactor, a polymer product recovery means to recover polymer product from the reactor and beneath the distribution plate, a fluidizing medium recycle line to recycle the fluidizing medium from and to the reactor, and a heat exchanger in the recycle line to remove heat of reaction from the recycled fluidizing medium.

Abstract: In a process for preparing homo- or co-polymer of ethylene, in which ethylene alone or mixed with one or more other unsaturated organic compounds capable of forming a copolymer with ethylene is subjected to a high pressure and a high temperature in a reactor in the presence of an initiator or a catalyst, in which the mixture of polymer and unconverted monomer discharged out of the reactor is expanded to, practically, atmospheric pressure with the aid of an expansion device in two or more steps, and in which the polymer present in the expanded mixture is separated from the mixture in the solid state, the improvement which comprises obtaining the polymer in a fibrous form by supplying the mixture to the last stage of the expansion device at such a pressure and temperature that, during the expansion, in this last stage, the polymer passes from the liquid phase to the solid phase.

Abstract: An essentially total reactor off-gas recycle process essentially isobaric in nature is herein disclosed for use in polymerizations wherein a polymerizable monomer or a mixture thereof is polymerized in a vapor state polymerization process using a stirred-bed, quench-cooled, horizontal reactor.

Abstract: Vinyl sulfonate monomers are recovered from an aqueous stream by bringing the stream into contact with activated carbon to allow the carbon to adsorb the monomers from the stream. The sulfonate monomers are subsequently removed from the carbon by bringing an aqueous solution of acrylonitrile into contact with the carbon. The acrylonitrile replaces the sulfonate monomers on the carbon to thereby desorb the sulfonate monomers into the solution in a concentration such that the solution is useful as a feed stream directly to a polymerization reactor. The sulfonate monomers have the formula ##SPC1##Where R.sub.1 is --H or --CH.sub.3, R.sub.2 is --CH.sub.2 O--, --O--, or --CH.sub.2 , n is 0 or 1 and X is Na, K or H.

Abstract: Vinyl sulfonate monomers are recovered from an aqueous stream by bringing the stream into contact with activated carbon to allow the carbon to adsorb the monomers from the stream. The sulfonate monomers are subsequently removed from the carbon by bringing an aqueous solution of acrylonitrile into contact with the carbon. The acrylonitrile replaces the sulfonate monomers on the carbon to thereby desorb the sulfonate monomers into the solution in a concentration such that the solution is suitable as a feed stream to a polymerization reactor. The sulfonate monomers have the formula ##EQU1## where R.sub.1 is --H or --CH.sub.3, R.sub.2 is --CH.sub.2 -- or ##EQU2## in which R.sub.3 and R.sub.4 are either --H or --CH.sub.3 and X is H, Na or K.

Abstract: A continuous process for recycling hydrogen for reuse in making blends of olefin copolymers of high and low molecular weights which comprises copolymerizing ethylene with at least one higher olefin monomer in a solvent in separate reactors in the presence of a coordination catalyst, at least one, but not all, of said reactors containing hydrogen in an amount sufficient to produce low molecular weight copolymer. The resulting solutions of high and low molecular weight copolymers are mixed, unreacted monomers and hydrogen are flashed from the mixture, and the copolymer blend is isolated from the unflashed residue.

Abstract: A process of producing methyl methacrylate polymers is provided wherein the monomer are polymerized by a bulk polymerization procedure at 150.degree. to 180.degree.C with a conversion of 50 to 80% and the volatiles predominantly comprised of the unreacted monomer, separated from the polymer product, are cyclically reused as a part of the monomer feed for polymerization. In such a monomer feed cycle system, oligomers are substantially removed from the volatiles and then the volatiles are blended with a virgin monomer feed for polymerization, the content in the volatiles of impurities having boiling points of lower than 200.degree.C at normal pressure is maintained within the range of 5 to 20% by weight.

Abstract: Sulphur dioxide and unreacted monomer or mixture of monomers are separated and recovered from the polymer or copolymer slurry obtained by polymerizing acrylonitrile monomer or copolymerizing acrylonitrile monomer and a further ethylenically unsaturated monomer copolymerizable therewith in the presence of a catalytic system comprising sulphur dioxide or a sulphite, by a process comprising the steps of separately removing the sulphur dioxide and the monomer or mixture of monomers from the slurry in two distinct volatilization zones connected in series under decreasing subatmospheric pressures, scrubbing with water the sulphur dioxide vapors removed in the first zone and vapors of unreacted monomer or monomers removed in the second zone, and recycling the two resulting aqueous solutions to the polymerization or copolymerization medium.

Abstract: A method for producing solid polymers having a molecular weight greater than 50,000 from olefins wherein the olefin is polymerized in the absence of a liquid dispersion agent of a nature different from that of the olefin to be polymerized, and in contact with a prepolymer containing a small amount of transition metal of subgroups IV-b, V-b and VI-b having been produced by the polymerization of an olefin in a dispersion liquid containing a Ziegler-type catalyst.

Abstract: A continuous process for the polymerisation of olefinically unsaturated monomers in bulk or in solution in which at least a portion of the low-viscosity materials to be fed to the polymerization zone is thoroughly mixed with a portion of the high-viscosity contents of the polymerization zone in a mixing zone disposed upstream of the polymerization zone, which mixture is then continuously fed to the polymerization zone. The resulting polymers have a uniform composition and a narrow molecular weight distribution. They may be converted to shaped articles by thermoplastic methods.

Abstract: A process is provided for recovering hexane from the mixed recycle stream from a plurality of ethylene polymerization reactors. The recycle stream containing hexane and periodically vinyl acetate and/or an alkyl acrylate admixed with vinyl acetate to provide a mixed feed stream containing at least 45% by weight vinyl acetate. This feed stream is distilled at atmospheric pressure and all of the hexane is recovered as an overhead azeotrope containing about 57% hexane. The overhead fraction is redistilled at a superatmospheric pressure of at least 4 atmospheres in a second column. The overhead fraction of the second column will be enriched in vinyl acetate and pure hexane is recovered as a bottoms fraction from the second column. The vinyl acetate and/or alkyl acrylate contained in the bottoms fraction of the first column is recovered by atmospheric distillation in a third column.