Abstract: A method for reducing sheeting during polymerization of alpha-olefins in a low pressure fluidized bed reactor utilizing titanium or vanadium based compounds as catalysts together with alkyl aluminum cocatalysts wherein water is introduced water into said reactor in an amount sufficient to maintain the electrostatic levels at the site of possible sheet formation at levels which avoid sheeting without substantially altering the effectiveness of said catalysts.

Abstract: A catalyst and its use in polymerizing olefins, wherein the catalyst is prepared by contacting a support with a compound of titanium and/or vanadium.

Abstract: Generally, linear polyethylene containing long chain branching is obtained by polymerizing ethylene in the presence of a catalyst comprising a transition metal compound such as titanium chloride, an organoaluminum compound represented by the formula R.sub.1 R.sub.2 AlR.sub.p wherein R.sub.1 and R.sub.2 are the same or different hydrocarbyl groups having from 1 to 18 carbon atoms and R.sub.p is a polymeric hydrocarbyl group containing long chain branching aluminum alkyl cocatalyst.

Abstract: Stereoblock polymers of 1-olefins having a broad uni-, bi-, tri- or multimodal molecular weight distribution are obtained when a catalyst which comprises a chiral metallocene containing bridges and an alumoxane is used for the polymerization of the 1-olefins. The polymers are particularly highly suitable for the production of transparent films.

Abstract: A novel highly efficient process is disclosed for the production of substantially amorphous ethylene-propylene copolymers. The polymers have properties which make them applicable for use, e.g., as hot melt adhesives, as blending components in roofing materials, and as cable and wire flooding agents.

Abstract: Ethylene is polymerized using a Ziegler catalyst system consisting of (1) a titanium catalyst component and (2) an aluminum catalyst component, the component (1) used being the product (VI) which is obtained by a method in which (1.1) first (1.1.1) a carrier (I) and (1.1.2) a solution (II) of (IIa) a solvent, (IIb) a titanium trichloride and (IIc) magnesium chloride are combined with formation of a dispersion (III) and the latter is evaporated down with formation of an intermediate (IV), and (1.2) then (1.2.2) the intermediate (IV) obtained from (1.1), and (1.2.2) an aluminum component (V) consisting of (1.2.2.1) a complex of a certain oxacycloalkane and a certain aluminum compound and (1.2.2.2) if necessary, a certain free aluminum compound are combined, the resulting product (VI) being the catalyst component (1). In this process, a component (1) is employed which has been prepared using, in (1.1) under (1.1.

Abstract: Ethene homopolymers and ethene copolymers with minor amounts of higher .alpha.-monoolefins are prepared by polymerization of the monomer or monomers using a chromium trioxide catalyst which is obtained by a method in which (1) a finely divided, porous, silicate carrier is laden with (2) chromium trioxide or a chromium compound which is converted to chromium trioxide under the conditions of stage (3), and then (3) the intermediate resulting from stage (2) is heated in an oxygen-containing gas stream. In this process, a cocatalyst which consists of a lithiumalkyl used in addition to the chromium trioxide catalyst.

Abstract: Polymerization of olefins in the presence of a catalyst system comprising a titanium-containing component A associated with a chemically treated silica-containing composition and a dihydrocarbylmagnesium compound and a cocatalyst component B comprising metal hydride or organometal compound derived from an element of Groups IA-IIIA of the Periodic Table.

Abstract: Stereoblock polymers of 1-olefins having long isotactic sequences are obtained at industrially favorable polymerization temperatures using a catalyst which comprises a metallocene compound having cyclopentadienyl radicals which are substituted by chiral groups, and an alumoxane.

Abstract: Fluorinated pentanedione-stabilized metal driers provide coating compositions of extended pot life. Allyloxy activated surface coatings of free radical-polymerizable compounds having fluorinated pentanedione stabilized metal drier and peroxide free radical initiator provide durable films.

Abstract: Homopolymerization and copolymerization of ethene are carried out using a Ziegler catalyst system consisting of (1) a transition metal catalyst component prepared by a method in which (1.1) first (1.1.1) an inorganic oxide substance (I) as a carrier and (1.1.2) a solution (II) of (IIa) a certain oxahydrocarbon and (IIb) a mixture of (IIb1) a vanadium trichloride/alcohol complex, (IIb2) a titanium trihalide or titanium trihalide/alcohol complex and, if desired, (IIb3) a zirconium tetrahalide, are combined with formation of a suspension (III), the latter is evaporated down to form a solid-phase intermediate (IV), (1.2) then (1.2.1) the solid-phase intermediate (IV) obtained from (1.1), and (1.2.2) a dissolved organoaluminum compound (V), are combined with formation of a suspension, the resulting suspended substance being a solid-phase product (VI), (2) an organoaluminum catalyst component and (3) an organohalogen catalyst component.

Abstract: A process for producing polyolefins having a high stereoregularity, no smell and a good particulate form, without needing removal of catalyst residue contained in the resulting polyolefins, which process comprises polymerizing olefins by the use of a catalyst obtained by combining a solid product (II) as a solid catalyst component prepared through the following reaction steps I, II and III, with an organoaluminum compound component and an organic silicon compound component having Si-O-C bond: Step I of mixing and dissolving .circle.a an anhydrous Mg dihalide, .circle.b a specified orthotitanic acid ester or/and a specified polytitanic acid ester and .circle.c a saturated or unsaturated, mono- or polyhydroxy alcohol of 1.about.20 C in an inert hydrocarbon solvent to obtain a component (A), Step II of mixing (A) with a component (B) consisting of .circle.d an aliphatic or aromatic monocarboxylic acid ester, .circle.e a specified halogenated aluminum and .circle.

Abstract: A method and apparatus for continuously manufacturing water absorbing resin. A mixed monomer solution is stored in a storage vessel and a polymerization initiator stored in an initiator storage vessel. The monomer solution is fed by gravity or otherwise through a conduit to a lower position (below the liquid surface) of a reaction chamber of a reaction vessel at a rate of, for example, 4 gallons per minute. Simultaneously, the polymerization initiator is fed at a rate of, for example, 0.2 gallons per minute by gravity or otherwise through a conduit to an opposite side of the reaction chamber, again at a lower portion (below a continuously maintained liquid level) to begin polymerization. The reaction product forms from an upper surface of the reactant mixture (mixed monomer solution plus initiator) and travels upwardly through a truncated frustoconical cone shaped upper portion of the reaction chamber as a solid resin.

Abstract: Polycyclopentadienylene vinylene exhibiting solvent resistance, e.g. to chlorinated solvents such as chloroform and methylene chloride and to amine solvents such as dimethylformamide, is prepared by removal of acid groups from precursor polymer having norbornene dioxo derivatives.

Abstract: A vanadium catalyst composition comprising:(i) the reaction product of a vanadium trihalide wherein the halogen is chlorine, bromine, or iodine, or mixtures thereof, and an electron donor, which is a liquid, organic Lewis base in which the vanadium trihalide is soluble;(ii) a silica support onto which component (i) is impregnated;(iii) a salt admixed with the silica support, the cation of said salt being selected from the group consisting of Groups I and II of the Periodic Chart of the Atoms;(iv) a halocarbon promoter; and(v) a hydrocarbyl aluminum cocatalyst.

Abstract: A vanadium catalyst composition comprising:(i) the reaction product of a vanadium trihalide wherein the halogen is chlorine, bromine, or iodine, or mixtures thereof, and an electron donor, which is a liquid, organic Lewis base in which the vanadium trihalide is soluble;(ii) a silica support onto which component (i) is impregnated;(iii) a salt admixed with the silica support, the cation of said salt being selected from the group consisting of Groups I and II of the Periodic Chart of the Atoms;(v) a halocarbon promoter; and(v) a hydrocarbyl aluminum cocatalyst.

Abstract: The present invention is a process for polymerizing trialkylsilylacetylene derived monomers to form the corresponding poly(trialkylsilylacetylene) polymer. The polymerization reaction is carried out in the presence of an organic solvent over a catalyst comprising a halide of a transition metal of group Vb or VIb. The molecular weight of the resultant polymer is decreased by adding to the reaction mixture, in a concentration between about 0.5-25 wt. %, a compound having the structural formula ##STR1## wherein each R is independently methyl, C.sub.2-4 alkyl or phenyl, and n is from 1 to 100.

Abstract: Disclosed is a method of making a cross-linked poly(dicyclopentadiene) with a metathesis-catalyst system, where the metathesis-catalyst system contains an organoaluminum or organoaluminum halide activator and a pentavalent tantalum catalyst. In a preferred embodiment, the cross-linked polymer is formed by combining, in a first place, a plurality of reactant streams, one reactant stream which contains the activator, a second reactant stream which contains the catalyst and at least one reactant stream which contains dicyclopentadiene; then injecting the combined reactant streams into a second place, such as a mold, where polymerization occurs. Use of the pentavalent tantalum catalyst results in the formation of a cross-linked polymer having less color and greater transparency than cross-linked poly(dicyclopentadiene) made without a pentavalent tantalum catalyst.

Abstract: A manufacturing method of polyolefin characterized in that at least one kind of olefins is allowed to polymerize in the presence of a catalyst system comprising(A) solid catalyst ingredient (A) obtained through the successive reaction steps, wherein, with a homogeneous solution involving(i) at least one member selected from metallic magnesium and hydroxylated organic compounds and oxygen-containing organic compounds of magnesium, and(ii) at least one kind of oxygen-containing organic compounds of titanium, are allowed to react in sequence with:(iii) at least one kind of organoaluminum compounds, then(iv) at least one kind of silicon compounds and further(V) at least one kind of halogenated aluminum compounds and(B) at least one kind of catalyst ingredients (B) selected from organometallic compounds, the metal of which belongs to Ia, IIa, IIb, IIIb or IVb group in the periodic table.

Abstract: The pressure in a continuous high pressure polymerization system, in which ethylene, with or without comonomers, is polymerized under high pressures and temperatures and the unconverted amounts of gas are recycled through the high pressure recycle gas system into the polymerization system, is rapidly reduced to below the particular reaction pressure when predetermined limiting pressure and/or temperature values are exceeded or when other faults occur by opening one or more pressure-relief apparatuses mounted on the high pressure polymerization system and transferring the hot let-down reaction mixture from the polymerization system via one or more let-down lines through one or more separator systems into the atmosphere, by a process in which the high pressure polymerization system is divided into a plurality of isolated sections at the same time as the let-down process is triggered and only the section in which the let-down process is triggered is let down to the atmosphere.