Curable precursor compositions for adhesives (e.g., pressure sensitive adhesives) and related articles, assemblies, and methods. The provided compositions contain a mixture comprising 50 to 100 parts by weight of a first polymerizable component, 0 to 50 parts by weight of a second polymerizable component, a transition metal complex soluble in the mixture, and an effective amount of a polymerization initiator, thereby allowing for the formation of high molecular weight polymer with essentially no gel content that can be easily processed via established hot melt techniques (i.e., a hot melt processable adhesive), even in the absence of chain transfer agents or crosslinking agents.

A process for producing a polyolefin comprising contacting one or more olefinic monomers in the presence of one or more catalysts, wherein one or more of the catalysts hasthe following structure: wherein M is a Group III or Lanthanide metal that is in a +3 formal oxidation state and wherein the contacting occurs in the absence of any activator is provided.

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The invention relates to neodymium-catalyzed polybutadienes (NdBR) comprising >95 wt % of cis-1,4 units and <1 wt % of 1,2-vinyl content, based on the neodymium-catalyzed polybutadiene, wherein the NdBR evinces a molar mass breakdown of not less than 25%.

Catalyst component for the polymerization of olefins comprising Mg, Ti and an electron donor of formula (I) ##STR00001##
Where R.sub.1 and R.sub.2, independently, are selected from hydrogen and C.sub.1-C.sub.15 hydrocarbon groups, optionally contain an heteroatom selected from halogen, P, S, N, O and Si, which can be fused together to form one or more closed cycles and A is a bivalent bridging group.

Silica-coated alumina activator-supports, and catalyst compositions containing these activator-supports, are disclosed. Methods also are provided for preparing silica-coated alumina activator-supports, for preparing catalyst compositions, and for using the catalyst compositions to polymerize olefins.

A method for producing a solid catalyst component for olefin polymerization produces a novel solid catalyst component for olefin polymerization that achieves excellent olefin polymerization activity and activity with respect to hydrogen during polymerization, and can produce an olefin polymer that exhibits a high MFR, high stereoregularity, and excellent rigidity. The method includes a first step that brings a magnesium compound, a tetravalent titanium halide compound, and one or more first internal electron donor compounds selected from specific aromatic dicarboxylic diesters into contact with each other to effect a reaction, followed by washing, a second step that brings a tetravalent titanium halide compound and one or more second internal electron donor compounds into contact with a product obtained by the first step to effect a reaction, followed by washing, and a third step that brings one or more third internal electron donor compounds into contact with a product obtained by the second step to effect a reaction.

The invention relates to a catalyst system comprising I. a solid reaction product obtained by reaction of: (a) a hydrocarbon solution comprising (1) an organic oxygen containing magnesium compound or a halogen containing magnesium compound and (2) an organic oxygen containing titanium compound and (b) a mixture comprising a metal compound having the formula MeR.sub.nX.sub.3-n wherein X is a halogenide, Me is a metal of Group III of Mendeleev's Periodic System of Chemical Elements, R is a hydrocarbon radical containing 1-10 carbon atoms and 0n3 and a silicon compound of formula R.sub.mSiCl.sub.4-m wherein 0m2 and R is a hydrocarbon radical containing 1-10 carbon atoms wherein the molar ratio of metal from (b): titanium from (a) is lower then 1:1 and II. an organoaluminium compound having the formula AlR.sub.3 in which R is a hydrocarbon radical containing 1-10 carbon atoms.

The present invention is directed to a process for the production of high density polyethylene by polymerisation of ethylene in the presence of a supported chromium oxide based catalyst which is modified with an organic compound comprising oxygen and a nitrogen atom which is selected from the group consisting of saturated heterocyclic organic compounds with a five or six membered ring, amino esters and amino alcohols. Such organic compounds allow manufacturing of HDPE with increases molecular weight distribution and increased molecular weight.

Amorphous propylene-ethylene copolymers are described herein that can include high amounts of ethylene and exhibit desirable softening points and needle penetrations. The desirable combinations of softening points and needle penetrations in these propylene-ethylene copolymers allow them to have a broad operating window. Due their broad operating window, the propylene-ethylene copolymers can be utilized in a wide array of applications and products, including hot melt adhesives.

Provided are a solid titanium catalyst component for ethylene polymerization which can polymerize ethylene at a high activity and which can provide an ethylene polymer having an excellent particle property, an ethylene polymerization catalyst and an ethylene polymerization method in which the catalyst is used. The solid titanium catalyst component (I) for ethylene polymerization according to the present invention is obtained by bringing a liquid magnesium compound (A) including a magnesium compound, an electron donor (a) having 1 to 5 carbon atoms and an electron donor (b) having 6 to 30 carbon atoms into contact with a liquid titanium compound (C) under the presence of an electron donor (B) and includes titanium, magnesium and a halogen. The ethylene polymerization catalyst of the present invention includes the component (I) and an organic metal compound catalyst component (II). Further, the ethylene polymerization method of the present invention is a method for polymerizing ethylene under the presence of the catalyst.