Abstract: Polymers of excellent impact strength, reduced particle size, and enhanced proportions of fines are obtained in the bulk polymerization of a vinyl halide or mixture thereof with comonomer(s) in the presence of a high molecular weight polyolefin added to the polymerization mass upon conversion of 0 to about 20% by weight of monomer(s) to polymer, by removing from the polymerization mass during the thick paste state thereof sufficient vinyl halide to adjust the effective concentration of polyolefin to above about 3.5% based on vinyl halide. The resultant product which contains an enhanced proportion of fines and is devoid of massive agglomerates, requires less mechanical work in comminution or shorter heating in melting in subsequent conventional processing steps.

Abstract: An olefin is polymerized in a hydrocarbon diluent in a turbulent reaction zone to produce particles of polymer which are substantially insoluble in the diluent. Fouling of the reactor by adherence of polymer particles to the walls of the reactor is reduced by adding to the reaction medium a composition which comprises a porphyrin compound, alone or together with a metal alkyl sulfosuccinate. This composition is also useful as an antistatic agent for liquid hydrocarbons and halohydrocarbons.

Abstract: This invention relates to a polymerization reaction vessel having a coating on the inner surfaces thereof resulting from applying thereto a coating composition containing, as a primary ingredient, an alkali soluble dye dissolved in an aqueous alkali metal hydroxide solution or an ammonium hydroxide solution. When polymerizing olefinic monomers, such as vinyl halides, vinylidene halides, and vinylidene monomers having at least one terminal CH.sub.2 =C< grouping, and mixtures thereof, in the presence of said coating, polymer build-up on the inner surfaces of the reaction vessel is substantially eliminated. Further, multiple charges or batches of polymer can be made in said internally coated reaction vessel without opening the same between charges thus preventing the escape of unreacted monomer to the atmosphere.

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: 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: A method for the continuous production of crystalline ethylene-propylene block copolymers containing propylene as the major component and having excellent physical properties as that by a batch process in a slurry-phase by homopolymerizing propylene and then copolymerizing ethylene and propylene in the presence of an inert hydrocarbon solvent and a stereoregular polymerization catalyst in polymerization vessels connected in series, which is characterized by homopolymerizing propylene in three polymerization vessels, wherein the inner pressure of the vessels is decreased in order so as to make the inner-pressure difference between each consecutive two vessels from 1 to 3 kg/cm.sup.

Abstract: In conventional olefin polymerization using TiCl.sub.3 -containing Ziegler type catalysts, the catalyst-containing reaction product may be de-ashed by treatment with titanium-solubilizing compounds such as alcohols and the polymer product from the de-ashing step washed with a hydrocarbon to separate it from catalyst residue. It is desirable to treat the dirty hydrocarbon wash liquid to recover purified hydrocarbon suitable for recycle to the polymerization reaction. According to this invention the dirty hydrocarbon wash liquid is treated with an epoxy compound in the presence of an alcohol and distilled to recover purified hydrocarbon suitable for recycle.

Abstract: Polymers of at least two different alpha monoolefinic monomers capable of polymerizing with themselves and each other. The polymers comprise a plurality of polymer chains along which the proportion of mer units provided by a first such monomer for a given first chain length gradually increases as the proportion of mer units provided by a second such monomer along the first chain length gradually decreases to a second chain length along which the proportion of mer units provided by the first and second monomers, respectively, remain substantially constant throughout said second chain length. Also, included are polymers of this type wherein the polymer chains comprise a third chain length along which the proportion of mer units provided by the first monomer is greater than the minimum proportion of the same type of mer units in the given first chain length and remains substantially constant throughout the third chain length.

Abstract: Polymerization of a mono-.alpha.-olefine monomer is effected by contacting the gaseous monomer with a solid phase comprising polymer and catalyst at a pressure and temperature which are such that the temperature is in the range from tp + 0.1.degree. C up to tp + 5.0.degree. C, where tp is the temperature at which the monomer condenses at a pressure which is equal to the monomer partial pressure within the polymerization vessel.

Abstract: According to the invention, polyaddition products containing imide groups are manufactured by reacting certain polyimides (preferably maleimides) with polyhydric alcohols in the presence of basic compounds. The preferred embodiment (E) relates to the use of catalysts as basic compounds. In particular, amines and alkali metal compounds can be used. A further embodiment (F) relates to the use of primary polyamines as basic compounds. In the latter case, the polyamine participates in the polyaddition mechanism, that is to say the molecules are incorporated into the polyaddition products. In this latter case, catalysts can also be used additionally.

Abstract: Process for the manufacture of shaped articles of a mixture of polystyrene and a copolymer of ethylene with vinyl ester, acrylate or methacrylate. To this end, the said copolymers having a content of from 3 to 40% by weight of unsaturated ester are reacted with monomeric styrene in aqueous suspension in the presence of free-radical polymerization initiators. Whereas a portion of the styrene used is directly grafted onto the ethylene copolymer, the remainder of the polymerized styrene is present in a finely divided state as a homopolymer beside or within the grafted ethylene copolymer. There are obtained homogeneous shaped articles having a styrene content of more than 50% by weight.

Abstract: A new catalyst and method of making polymers therewith and the process of preparing the catalyst in which the catalyst is prepared by dispersing on a finely divided carrier material, particularly a difficulty reducible inorganic support such as silica, an organic chromium compound or complex such as a chelate derived from an N-nitroso-substituted N-arylhydroxylamine, N-nitroso-substituted hydroxamic acid, N-aryl-substituted hydroxamic acid, or an aromatic hydroxamic acid with or without an N-substituent and activating the resulting mixture by heating at an elevated temperature in a non-oxidizing atmosphere.

Abstract: Polypropylene molding compositions of improved impact strength are obtained by subjecting certain block copolymers of ethylene and propylene to controlled oxidative degradation.

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: 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: 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: Process for the continuous production of a polymer of an .alpha.-olefin monomer. The monomer is polymerized in bulk, employing a screw conveyor as the reactor. The monomer can be in liquid phase when introduced into the conveyor. By the process, the use of diluents is avoided.

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: Block copolymers are produced by (i) polymerizing ethylene or propylene, or copolymerizing the same with another .alpha.-olefin of 2 to 7 carbon atoms in the presence of a Ziegler-type catalyst, and (ii) copolymerizing the resulting polymer or copolymer with a radical-polymerizable vinyl compound (e.g., methyl methacrylate) in the presence of an organic sulfoxide.

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.