Snamprogetti S.p.a.

Eniricerche S.p.a.

Anic S.p.a.

Enichem Sintesi S.p.a.

Dow Corning Corporation

Enichem Synthesis S.p.a

Eniricherche S.p.a.

Enichimica Secondaria, S.p.a.

Snamprogetti

Guglielmo Bertolini

Alberto Greco

Arnaldo Roggero

Sebastiano Cesca

Mario Bruzzone

Mario G Clerici

Maurizio Brunelli

Carlo Busetto

Aldo Giusti

Giuseppe Braca

Glauco Sbrana

Anna M Galletii

Gianfranco Pazienza

Alessandro Ricci

Omero Zavattini

A catalyst active in the polymerization of ethylene or the copolymerization of ethylene with unsaturated monomers consists of a nickel complex catalyst bonded to a polystyrene substrate, and definable by the general formula (I): ##STR1## where R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 have the meanings given in the description. The preparation is described of the catalyst and its use in the polymerization of ethylene and the copolymerization of ethylene with other unsaturated monomers.

Polymerization catalyst, the process for its preparation and its use in

Sterically hindered amino compounds definable by the general formula (I): ##STR1## where R represents a hydrogen atom, a C.sub.1 -C.sub.18 alkyl radical or a C.sub.7 -C.sub.18 alkaryl radical, are useful as organic polymer stabilizers. Processes for preparing these compounds are described.

Sterically hindered

Polymeric stabilizer compounds are formed by an organic polymeric matrix, of paraffinic character, deriving from a hydrogenated polydiene and bearing bonded at at least one chain end a sterically hindered aminic function. Such polymeric stabilizer compounds are obtained by means of a process, which provides:

Polymeric stabilizer compounds and process for their preparation

Solid polymeric stabilizer compound containing the hydroxybenzophenone function, having the general formula (I): ##STR1## wherein: m=from 0.01 to 0.99 (preferably from 0.1 to 0.6);

Process for the preparation of solid polymeric stabilizer compounds

Solid polymeric stabilizer compounds are disclosed comprising an organic polymeric matrix, to which are linked groups containing a sterically hindered aminic function, the organic polymeric matrix being a polymeric matrix of a vinyl-aromatic, aromatic with heteroatoms, dienic or olefinic polymer, containing hydrogen atoms replaceable by metal atoms, the groups containing the sterically hindered aminic function replacing, at least partially, said replaceable-by-metal hydrogen atoms of the matrix. Also disclosed are processes for the preparation of said solid polymeric stabilizers and stabilized polymeric compositions comprising an organic polymer and a stabilizing amount of said solid polymeric stabilizers.

Solid polymeric stabilizer compounds and process for their manufacture

Isobutylene copolymers, cross-linkable under ambient humidity conditions, characterized by the presence of pendant functions containing a silyl radical, are prepared by a process comprising the preliminary formation of new copolymers of isobutylene with a triene containing a system of two conjugate double bonds in position 1,3 and at least one other double bond of vinyl type, followed by the silylation of the polymers thus produced by means of a silicon derivative chosen from those of formula (I) or (II): ##STR1##

Isobutylene-triene copolymers cross-linkable under ambient humidity

For preparing polyoxyalkylenediol-.alpha.,.omega.-bisallyl policarbonates, diallyl carbonate is reacted in a first reaction stage with a polyoxyalkylenediol having a mol wt between 400 and 4500 in the presence of a transesterification catalyst at a temperature in the neighborhood of 100.degree. C. and under reduced pressures, whereafter, in a second reaction stage, the product as obtained from the first stage is treated at a temperature between 70.degree. C. and 150.degree. C. under reduced pressures, still in the presence of a transesterification catalyst. By so doing, the chain extension of the bisallyl carbonate of the polyoxyalkylenediol is achieved, whereas the unreacted diallyl carbonate coming from the first stage, and that produced in the second stage, are eliminated, and the final reaction product can thus be collected.

Polyoxyalkylenediol-.alpha.,.omega.-bisallyl polycarbonate useful as a

Alkoxides of transition metals, selected from among tetravalent Ti, tetravalent and pentavalent V, tetravalent Cr and tetravalent Zr, actinides and lanthanides, are reduced to corresponding alkoxides of lower valency by reacting such higher valency metal alkoxides, in liquid phase, with vapors of metals of the alkaline earth group, the III group and the IV group metals and magnesium. Very efficient polymerization catalysts for the polymerization of unsaturated compounds are thus obtained.

Process for reducing metal alkoxides, and the use of the compounds so

Novel salt-like compounds adapted to be used as component of catalytic systems in the polymerization of ethylenically unsaturated monomers are disclosed: these compounds are obtained by reacting halides of transition metals or of aluminium with halides of alkaline earth metals, in the presence of phosphorous oxide derivatives which have the function of solvating agents. Also oxyhalides of transition metals lie within the scope of the invention.

Compounds formed by combining transition metal halides or oxyhalides, or

An alpha-olefin such as ethylene is polymerized in the presence of a catalyst system consisting of (1) an alkyl-halide, alkyl-derivative or hydride of a metal belonging to one of the first three groups of the periodic system and (2) the combination product of a transition metal chloride and titanium trichloride, supported on a previously chlorinated material such as chlorinated .alpha.-alumina having a high superficial area.

Process for the polymerization of alpha-olefins, catalyst employed in

An alpha-olefin such as ethylene is polymerized in the presence of a catalyst system consisting of (1) an alkyl-halide, alkyl-derivative or hydride of a metal belonging to one of the first three groups of the periodic system and (2) the combination product of a transition metal chloride and titanium trichloride, supported on a previously chlorinated material such as chlorinated .gamma.-alumina having a high superficial area.

An alpha-olefin such as ethylene is polymerized in the presence of a catalyst system consisting of (1) an alkyl-halide, alkyl-derivative or hydride of a metal belonging to one of the first three groups of the periodic system and (a) the combination product of a transition metal chloride and titanium trichloride said transition metal chloride being derived from the reaction of a transition metal carbonyl and titanium tetrachloride.

Alpha olefin polymerization catalyst comprising an alkyl halide and a

Ethylene is polymerized through the use of an improved catalyst system consisting of a carrier such as neodymium oxide having a high superficial area, an aluminum compound such as triisobutylaluminum and the combination product of titanium trichloride and an isostructural chloride of another transition metal prepared by impregnating the carrier with a solution of a carbonyl derivative of the other transition metal, refluxing the impregnated carrier with titanium tetrachloride until that carbonyl derivative is converted to the chloride of the other transition metal, and then removing the excess of titanium tetrachloride.

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Pavia, Italy

Guglielmo Bertolini