Abstract: This invention relates to a method of preparing graft polymers by mass polymerizing a mixture of polymerizable vinyl monomers in the presence of an elastomer to which the vinyl monomers are to be grafted, the elastomer being soluble in at least one of the vinyl monomers and also insoluble in at least one of the vinyl monomers, which comprises:A. dissolving an elastomer in at least one monomer in which it is soluble;B. initiating a mass prepolymerization reaction;C.introducing the monomer or monomers in which the elastomer is insoluble during the prepolymerization reaction;D. completing the addition of the monomer or monomers prior to the phase inversion of the reaction medium; andE. completing the polymerization.

Abstract: Conjugated dienes and alpha-olefins, such as butadiene and propylene, are copolymerized by a new catalyst system which gives copolymers containing a high proportion of the alpha-olefin with accompanying desired properties. This catalyst system comprises: (1) A titanium or vanadium halide, preferably chloride, (2) an aluminum hydrocarbon compound which also has Cl, Br or H attached to the Al atom and preferably the hydrocarbon group or groups are alkyl groups which have 1-8 carbon atoms in each of said alkyl groups and (3) CS.sub.2. The copolymers produced by this process have molecular weights in the range of 100,000-5,000,000; referably 250,000-500,000, and other desirable properties.

Abstract: Novel catalysts are provided for the polymerization of olefins such as ethylene. The catalysts consist essentially of a chromium compound supported upon an inorganic carrier containing aluminum and arsenate moieties. The inorganic carrier is an amorphous precipitate of aluminum arsenate, or an amorphous coprecipitate containing aluminum and arsenate moieties in proportions such that the aluminum and arsenic are present in an atomic ratio in the range of 5:1 to 1:1. The catalysts are particularly useful for polymerizng ethylene in a Particle Form Process in that the catalysts have essentially no induction period and provide ethylene polymers having a desirably-broad molecular weight distribution and a desirably-high melt flow shear ratio.

Abstract: A reactor for vinyl chloride polymerization in aqueous dispersion and inside said reactor at least one polished surface provided by a layer constructed from a Cr/Ni stainless steel of Cr content 13-30 wt % and Ni content 20-35 wt %.Preferably the layer provides at least part of the interior surface of the body of the reactor.A process for the production of a vinyl chloride polymer in such a reactor is also disclosed.

Abstract: A hindered phenolic antioxidant stablizer for polyolefins is rendered extraction resistant by complexing it with an agent containing complexing groups derived from N-vinyl-2-pyrrolidone or a N-dialkyl substituted amino alkyl ester of an .alpha.,.beta.-unsaturated carboxylic acid.

Abstract: In the aqueous polymerization of vinyl chloride and vinylidene chloride polymers and copolymers, the polymer build up normally experienced in many areas of commercial polymerization reactors is reduced, or when such polymer build up does occur it is more readily removed, when these trouble areas in polymerization reactors are coated with a latex-modified portland cement composition, the polymer in said latex containing carboxyl groups and the polymer having a Tg .degree. C. of less than about 40.degree. C., preferably less than about 25.degree. C.

Abstract: The present invention relates to novel polymeric compositions of styrene and amorphous polyolefins which include amorphous polypropylene, amorphous propylene/alpha-olefin copolymers and blends thereof and to processes for their preparation. These polymeric compositions are useful in preparing hot melt adhesives.

Abstract: Olefin polymerization catalysts are prepared by depositing a chromium compound and an aluminum compound on an inorganic support material and heating the support material in a non-reducing atmosphere at a temperature above about 300.degree. C up to the decomposition temperature of the support material. The supported chromium and aluminum compound is then combined with a metallic and/or non-metallic reducing agent, to provide a catalyst system useful in the polymerization of 1-olefins.

Abstract: Copolymer substantially free from compositional drift can be produced in a batch-type addition copolymerization process to a high degree of conversion by initiating the reaction in a monomer-containing phase (optionally dispersed in another phase of a reaction mixture) containing the monomers at mole ratios f.sub.i such that the monomers will initially be incorporated into copolymer at the desired mole ratios F.sub.i and sustaining the reaction while simultaneously controlling the addition each monomer to the phase in which the copolymerization reaction is continuing according to the relationQ.sub.i = f.sub.i Q.sub.0 + (F.sub.i - f.sub.i Q.sub.0 /Q.sub..infin.)Z,where Q.sub.i is the running cumulative moles of monomer i added to the phase in which reaction is occurring (including that initially present), Q.sub.0 is the total moles of all monomers initially present in that phase, Q.sub..infin.

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 manufacture of olefin polymers by polymerization of monoolefins using a silicic xerogel/chromium trioxide catalyst obtained by (1) synthesizing a particulate silicic xerogel, (2) doping said xerogel with chromium trioxide or a chromium compound capable of converting to chromium trioxide under the conditions of stage (3) and (3) heating the resulting product in a gas stream containing oxygen. The silicic xerogel/chromium trioxide catalyst used is one which has been obtained by (1) synthesizing the silicic xerogel in the first stage by (1.1) starting with a silicic hydrogel having a relatively high solids content, (1.2) extracting water from said hydrogel by means of an alkanol and/or alkanone until the organic liquid absorbs no further water, (1.3) extracting the organic liquid used in stage (1.

Abstract: Polymeric fibers are produced from a polymer-solvent solution without mechanical agitation means by supplying a polymer solution in a solvent to a radial-symmetrical mixing chamber and causing a rotary flow therein which subjects the polymer to shearing forces while, at the same time, adjusting the temperature of the polymer-solvent mix to just below the precipitation temperature of the polymer. Under these conditions a polymeric fiber precipitates which, after separation from the solvent, is useful in the preparation of paper and textile products.

Abstract: Process for preventing build-up in the reactors used in the free radical polymerization of ethylenically unsaturated monomers, and more particularly of vinyl chloride, in which the reactor walls are subjected to heat treatment before the reactors are charged in preparation for the polymerization process.

Abstract: Reliable continual preparation of polymers is obtained using a tubular reactor by intermittently feeding monomer, permitting substantial polymerization, adding additional monomer to displace a portion of the polymer formed and repeating the foregoing cycle. Plugging of the reactor is avoided.

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: This invention relates to a process for the manufacture of olefin polymers by polymerization of monoolefins with the aid of a silicic xerogel/chromium trioxide catalyst obtained by (1) synthesizing a particulate silicic xerogel, (2) doping this xerogel with chromium trioxide or a chromium compound which converts to chromium trioxide under conditions of stage (3) and (3) maintaining the resulting product at an elevated temperature in a water-free oxygen-containing stream of gas. The characteristic feature of the process of the invention is that the silicic xerogel/chromium trioxide catalyst used is one obtained by (1) synthesizing the silicic xerogel in the first stage as follows: (1.1) taking an aqueous solution of a sodium silicate, (1.2) substituting substantially all of the sodium ions contained in said solution by hydrogen ions by means of an ion exchanger, (1.3) introducing a water-soluble aluminum salt into the resulting aqueous silicic acid solution, (1.

Abstract: A method for avoiding decomposition of ethylene during polymerization in a tube form reactor having one or more side branches opening into the reactor wherein the diameter of the side branches is made to be not greater than about 12 mm and a flow number is maintained at between about 0.20 m.sup.2 /sec. and 0.55 m.sup.2 /sec, the flow number being defined as the product of the internal diameter of the tube reactor and the rate of flow of the reactant through the reactor. Flow numbers greater than 0.55 m.sup.2 /sec can be used as long as the diameter of the side branches is reduced to not more than 10 mm.

Abstract: A catalyst prepared by (1) forming a mixture of a finely divided support such as silica, alumina, zirconia or thoria and a chromium compound which may be either organic or inorganic followed by (2) adding a titanium compound, then (3) heat activating the reaction product of (2), and then (4) further heating in a gas that comprises oxygen. The disclosure also includes a method of polymerizing olefins with this catalyst and the process of preparing the catalyst.

Abstract: The method of making an active catalyst system, the catalyst system and a method of polymerizing olefins in which the catalyst system used is prepared by mixing an inorganic support such as silica with a chromium (III) amine complex and activating by heating the mixture to and at an elevated temperature in a non-oxidizing atmosphere.

Abstract: The reaction product of a chromium tris-diorganoorthophosphate and an alkyl aluminum halide is a catalyst for olefin polymerization and for alkylation of aromatic hydrocarbons with olefins.