Abstract: Polyolefins having a broad molecular weight distribution are obtained by polymerizing ethylene or higher alpha-olefins in the presence of a catalyst system comprising two or more metallocenes each having different propagation and termination rate constants and alumoxane.

Abstract: A aliphatic hydrocarbon soluble mixed aluminum hydrocarbyl-Lewis base co-catalyst composition comprising (i) at least two different classes of aluminum hydrocarbyls the first being an aluminum hydrocarbyl halide, the second being an aluminum hydrocarbyl hydride and/or aluminum trialkyl and (ii) at least one Lewis base represented by the formula: ##STR1## wherein each Y can be -OR', -NR.sub.2 ' and R' with the proviso that at least two be -OR' or -NR.sub.2 ', Z is an alkylene radical forming a 5 or 6 membered ring with the carbonyldioxy group or Z is alkyl substituted alkylene group wherein the alkyl radical can have from 1 to 8 carbon atoms, R is an aryl, allyl or alkyl group having 1 to 20 carbon atoms and R' is an alkyl, cycloalkyl, aryl or aralkyl radical having from 1 to 20 carbon atoms.The co-catalyst is employed with a titanium halide catalyst for the polymerization of olefins to obtain a advantageous balance of catalytic activity and polymer product stereoregularity.

Abstract: Isotactic-stereoblock polypropylene comprising recurring polypropylene units, said isotactic-stereoblock polypropylene characterized by comprising alternating blocks of monomers having an average block length greater than 2 having methine carbons with the same relative configuration and wherein the methine carbon atoms in adjacent blocks are of opposite configuration.

Abstract: A catalyst component for polymerizing ethylene alone or with another alpha-olefin having from 3 to 18 carbon atoms at temperatures greater than about 150.degree. C. which catalyst component is the product obtained by treating at least one dehydrated particulate support material, such as silica, having an average particle size from about 0.05 to about 20 microns, preferably 1.0 to 10.0 microns, with(a) at least one dihydrocarbyl magnesium compound wherein the hydrocarbyl groups can be the same or different, such as butyl ethyl magnesium,(b) a transistion metal compound of Groups IVa, Va, or VIa of the Periodic Table, such as, for example, titanium tetrachloride, and (c) ethyl aluminum dichloride. In a preferred embodiment the particulate support material is treated with a halogenating agent prior to treatment with the transition metal compound.

Abstract: A catalyst component useful for (co)polymerizing ethylene under high temperatures and pressures comprising the reaction product obtained by treating a magnesium halide supported titanium halide precursor with transition-metal halide or oxyhalide, thoroughly washing the solid reaction product therefrom and prepolymerizing the washed solid product with an alpha-olefin having from 4-12 carbon atoms.

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 & 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 and an aluminum alkyl cocatalyst.

Abstract: Polyolefins, in particular polypropylene, are stabilized against UV degradation by a system of ethylene vinyl acetate, containing at least 20% by weight vinyl acetate and one or more of a nickel or zinc-N,N'-dialkyldithiocarbamate or a piperidine derivative such as bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate.

Abstract: A catalyst for polymerizing ethylene and .alpha.-olefins and process for producing ethylene polymers which comprises homopolymerizing ethylene or copolymerizing ethylene and other olefins in the presence of a catalyst comprising a catalyst component and an organoaluminum compound, said catalyst component being obtained by mechanically copulverizing (A) a magnesium halide and (B) magnesium hydrocarbyloxide at a molar ratio of B/A=0.5 to 1.5 and subsequently bringing the resulting pulverized product into contact with a tetravalent titanium halide in the presence of a hydrocarbon and/or halogenated hydrocarbon.

Abstract: A catalyst component for polymerization of olefins which is prepared by bringing a magnesium alkoxide, a halogenated hydrocarbon, and a titanium compound into contact with one another. The catalyst component together with a organoaluminum cocatalyst is used for the polymerization of olefins and especially for the homopolymerization of ethylene and copolymerization of ethylene with an .alpha.-olefin having from 3 to 10 carbon atoms.

Abstract: Extremely strong, i.e., non-friable TiCl.sub.3 Ziegler-type polymerization catalyst are obtained by prepolymerizing a reduced solid TiCl.sub.3 product with a mixture of propylene and linear C.sub.8 -C.sub.18 alpha-olefin to produce a reduced solid TiCl.sub.3 product containing 5 to 35 weight percent of a copolymer of propylene and C.sub.8 -C.sub.18 alpha-olefin having a ratio of the infrared spectrum of the copolymer at 720 cm.sup.-1 : the infrared spectrum of the copolymer at 975 cm.sup.-1 in the range of 0.04 to 0.20.

Abstract: Ethylene is homopolymerized or copolymerized with another olefin monomer in the presence of a catalyst system comprising organo metal cocatalyst and a titanium-containing catalyst component, such titanium-containing catalyst component being obtained by reacting together a porous particulate material, an organo magnesium compound, a halogen or interhalogen compound and titanium tetrachloride.

Abstract: A process and apparatus are provided for the production of a non-woven fabric by melt-blowing wherein one or more yarns, e.g. monofilaments, are added or charged into the fabric stream between the extruder and collector by means of a supporting and drawing pressure gas stream. In one embodiment means are provided to regulate flow of the gas stream. In another embodiment means are provided to reciprocate or to rotate through a small arc the one or more charging means.

Abstract: An artificial leather is made by impregnating a special nonwoven web substrate with an elastic polymer material. In another embodiment the substrate comprises a nonwoven fabric laminated to a woven or nonwoven fabric.

Abstract: A titanium trichloride catalyst component containing a minor amount of prepolymerized alpha-olifin and useful in the polymerization of alpha-olefins is produced by reducing titanium tetrachloride with an organoaluminum compound at low temperatures and then treating the resulting reduced solids product with about 1 to 1,000 wt. % alpha-olefin so as to obtain a prepolymerized titanium trichloride reduced solid. The prepolymerized reduced solid can thereafter be activated to a highly active prepolymerized titanium trichloride by treating the prepolymerized reduced solid with a halogenated hydrocarbon and a Lewis base complexing agent or titanium tetrachloride and a Lewis base complexing agent. The prepolymerized reduced solid and the prepolymerized activated titanium trichloride manifests substantially no evidence of friability upon being subjected to mechanical shearing forces.

Abstract: According to this invention, there is provided a magnesium-containing solid, obtained by contacting the reaction product of (1):a magnesium-containing solid, obtained by contacting the reaction product of:(a) metallic magnesium;(b) a halogenated hydrocarbon of the general formula RX in which R stands for an alkyl, aryl or cycloalkyl group having 1 to 20 carbon atoms, and X stands for a halogen atom; and(c) an alkoxy compound of the general formula X'.sub.m C(OR').sub.4-m in which X' stands for a hydrogenor halogen atoms, or an alkyl, aryl or a cycloalkyl group having 1 to 10 carbon atoms, R' stands for an alkyl, aryl or cycloalkyl group having 1 to 20 carbon atoms and m is 0, 1 or 2, with (2) an organic aluminum compound.The magnesium-containing solid is employed as a carrier for a transition metal halide. The supported transition metal halide in combination with an aluminum alkyl cocatalyst such as aluminum triethyl is usefully employed for the polymerization of olefins.

Abstract: A titanium trichloride catalytic complex is produced by reducing titanium tetrachloride with an organo-metal compound and then treating the resulting reduced solids product with a chlorinated saturated aliphatic hydrocarbon having three to eight carbon atoms in the presence of a complexing agent. The resulting titanium trichloride complex composition, when employed as a co-catalyst with an organo-metal compound for Ziegler-type catalysts in polymerization of .alpha.-olefins, results in uniform polymer grains with unexpectedly high polymerization activity and high stereoregular polymer yielding ratios.

Abstract: A titanium trichloride catalyst complex is produced by reducing titanium tetrachloride with an organo-metal compound and then activating the resulting reduced solids by treatment with a chlorinated hydrocarbon and titanium tetrachloride in the presence of a Lewis base complexing agent. The employment of the chlorinated hydrocarbon and titanium tetrachloride in the presence of the Lewis base complexing agent unexpectedly produces a synergistic effect whereby activating conditions, e.g., temperature, time and TiCl.sub.4 concentration can be employed resulting in a titanium trichloride complex having superior alpha-olefin polymerization properties as compared to titanium trichloride catalyst complexes obtained by treatment under the same conditions in the absence of either titanium tetrachloride or chlorinated hydrocarbon. Moreover, unexpectedly high yields of activated catalyst can be recovered without loss of activity.

Abstract: A supported titanium catalyst component is produced by cogrinding an organo aluminum catalyst component with a supported titanium (IV) halide on a magnesium halide. The resulting supported titanium halide catalyst component, when employed with an organo aluminum catalyst component to form a catalyst system is highly useful for the stereoregular polymerization of .alpha.-olefins as well as the copolymerization of .alpha.-olefins.

Abstract: Normally intractable polymers of the structure: ##STR1## wherein X is O or NH, provided at least one X is O, such as poly(parabanic acids) are made extrudable by composition with greater than 15 to 60 weight percent of phosphate ester of the structure (R.sub.1 --O).sub.3 P=O wherein R.sub.1 is: ##STR2## and each R.sub.2 and R.sub.3 is independently selected from H or --CH.sub.3 or (b) an alkyl radical having 1 to 8 carbon atoms.

Abstract: A process for producing a thermoplastic nonwoven fabric having a uniform thickness and optionally napped fibers according to a melt blowing method, which comprises blowing a fiber stream consisting of melt blown fibers and a gas at a high speed onto a plate within a valley-like fiber-collecting zone formed by two plates having a large number of pores, to form a uniform nonwoven fabric without scattering fibers.