Abstract: An active catalyst in the polymerization of alpha-olefins is obtained by:(i) bringing a dialkyl magnesium, or an alkyl magnesium halide into contact with a silicon or tin halide, in solution in an inert organic solvent, until a granular solid precipitates off;(ii) suspending said solid precipitate in an inert organic solvent and bringing it into contact with a compound which can be defined by the formula: ##STR1## wherein M represents a metal from Group IVB of the Periodic Table of Elements, and each R and C.sub.p has the meaning as reported in the disclosure, in order to form a granular solid catalyst; and(iii) recovering said solid catalyst from the resulting suspension.

Abstract: A supported catalyst for the (co)polymerization of alpha-olefins is obtained by putting the following products in contact with each other:(A) a metallocene derivative of a metal selected from the group consisting of transition metals and lanthanides, which is in itself capable of promoting the polymerization of alpha-olefins in the presence of or also without suitable activators;(B) an active support containing magnesium, halogen, titanium and smaller quantities of tin;(C) an organometal derivative of aluminium of which at least 50% of the aluminium atoms are bound to at least one alkyl carbon atom.Components (A) and (B) are preferably interacted first to obtain a supported metallocene derivative, which is then put in contact with (C) to obtain the desired catalyst. Alternatively, (B) and (C) are interacted and subsequently put in contact with (A).

Abstract: A catalyst active in the polymerization of alpha-olefins is formed by:(a) a bis(cyclopentadienyl) bis(amide) derivative of an element of Group IVB of the Periodic Table of the Elements, to be defined by means of the formula: ##STR1## wherein M represents a metal of Group IVB, each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, and Cp have the same meaning as reported in the disclosure, and(b) an aluminoxane co-catalyst.This catalyst finds use in the processes of ethylene and other alpha-olefins polymerization and copolymerization.

Abstract: A solid component of catalyst, active in the polymerization of propylene and other .alpha.-olefins in stereoregular polymers, is obtained:(i) by treating a non-activated silica support in particles with a tin tetrahalide, to at least partially block the hydroxylic groups of the silica and to obtain a blocked silica;(ii) by impregnating the blocked silica with magnesium dialkyl or magnesium alkyl halide to make the magnesium compound react with the tin compound and with possible residual hydroxylic groups of the silica and to obtain a support;(iii) by halogenating the support by contact with a halogenating agent selected from the halides of tin, antimonium or silicon to obtain a halogenated support;(iv) by titanating the halogenated support with an excess of a titanium tetrahalide to obtain a titanated support;(v) by putting the titanated support in contact with a Lewis base, to obtain a solid component of catalyst.

Abstract: A catalyst for the polymerization of olefins, containing magnesium, chlorine, aluminium and at least one transition metal, in a dispersed or emulsified form within an inert diluent, is obtained by:contacting, in an inert diluent, a magnesium dialkyl and aluminium trichloride, in a molar ratio equal or almost equal to 2/1, at a temperature lower than 105.degree. C. to obtain a catalyst precursor in a suspended form, or at a temperature higher than 105.degree. C. to form a catalyst precursor in the form of a colloidal emulsion, in the diluent used; andcontacting said suspended or emulsified precursor with at least one compound of a transition metal to form a catalyst in the form of a suspension or emulsion respectively.

Abstract: A supported solid component of catalyst, for the stereospecific polymerization of propylene and other .alpha.-olefins, is obtained by making a non-activated silica interact in succession with: (i) a magnesium dialkyl or halide of magnesium alkyl; (ii) a halogenating agent selected from silicon, tin and antimony halides; (iii) a titanium tetrahalide; and (iv) a Lewis base. A catalyst for the stereospecific polymerization of propylene and other .alpha.-olefins is composed of: (A) the solid component of catalyst; (B) an aluminium trialkyl or aluminium alkyl halide; and (C) an electron donor compound, capable of forming a complex compound with component (B).

Abstract: A solid component of catalyst for the (co)polymerization of ethylene is composed of a silica support and of a catalytically active part containing titanium, magnesium, chlorine and alkoxy groups, and is obtained by:(i) activating a silica support by contact with a solution of magnesium dialkyl, or magnesium alkyl chloride, in a liquid, aliphatic hydrocarbon solvent;(ii) impregnating the activated silica with a solution, in a liquid aliphatic or aromatic ester, of titanium tetrachloride and tetra-alkoxide in equimolecular or almost equimolecular quantities, and magnesium chloride; and(iii) treating the solid obtained in step (ii) with a proportioned quantity of aluminium alkyl sesquichloride.

Abstract: Solid component of catalyst for the (co)polymerization of ethylene, including magnesium, halogen and titanium, obtained by:(i) dissolution, in an inert organic solvent, of a magnesium dialkyl, or a magnesium alkyl halide, a tin halide (IV) and possibly also an alkyl halide and their contact until a granular solid precipitates from the solution;(ii) contact of said granular solid and its interaction with a titanium halide, alkoxide or halo-alkoxide, to form a solid component of catalyst.

Abstract: A solid component of catalyst for the (co)polymerization of ethylene, including magnesium, halogen and titanium, is prepared:(i) by dissolving a magnesium dialkyl, a silicon halide and at times also an alkyl halide, in an inert organic solvent and maintaining contact until a granular solid precipitates;(ii) putting this granular solid in contact and making it react with a titanium halide, alkoxide or halogen-alkoxide, to produce a solid component of catalyst; and(iii) activating this solid component of catalyst by contact with aluminium alkyl halide, if a titanium alkoxide or halogen-alkoxide has been used in phase (ii).

Abstract: A process for the preparation of a solid component of a catalyst active in the (co)polymerization of ethylene and able to form (co)polymers of ethylene having from middle to wide distribution of molecular weight and monomodal distribution of molecular weights, in processes operating in a single step, in suspension or in the gaseous phase. Said solid component of a catalyst contains magnesium, chlorine, silicon, titanium and at least another transition metal on a solid, granular and porous carrier and is obtained by treating the carrier, in succession, with: a compound of a metal selected from hafnium, zirconium or vanadium; a magnesium dialkyl or magnesium alkyl halide; a silicon chloride; and a titanium compound.

Abstract: The fluidity at low temperatures of compositions based on liquid hydrocarbons from refining is improved by the addition, preferably in solution, of ethylene/propylene/(conjugated diene) copolymers or terpolymers, containing 20-55% of propylene, optionally degraded by thermo-oxidation, and structurally characterized by values of at least one of X.sub.2 and X.sub.4 parameters, which are equal to, or lower than, about 0.02, indicative of the absence in the polymeric chain of propylene linking inversions.

Abstract: This invention relates to plastoelastomeric polyolefinic compositions comprising an intimate mixture of the following components, in the indicated percentages by weight:A) 10-50% of non cross-linked polypropylene;B) 2-10% of ethylene/propylene/(diene)non cross-linked elastomeric copolymer,C) 30-40% of polymeric product which is insoluble in xylene at 135.degree. C., comprising polypropylene and ethylene/propylene/(diene) copolymer, andD) 5-58% of an extender oil.This invention also relates to a process for preparing the above compositions, which consists in subjecting to vulcanization under dynamic conditions a mixture comprising, in % by weight:A) 20-80% of polypropylene,B) 80-20% of ethylene/propylene/(diene) elastomeric copolymer,C) 0.1-10%, referred to such copolymer, of a peroxide,D) 5-60%, referred to such peroxide, of a furan derivative as a cross-linking coadjuvant.and in adding, after vulcanization, the extender oil in an amount ranging from 6 to 100% calculated on the vulcanized product.

Abstract: Polyolefinic compositions endowed with a high impact strength, comprising:(a) 35-45% by weight of a C.sub.2 /C.sub.3 copolymer containing from 4 to 10% by weight of C.sub.2 and exhibiting a melt flow rate (M.F.R.) from 10 to 20 g/10 minutes at 230.degree. C. and 2.16 kg;(b) 35-45% by weight of a C.sub.2 /C.sub.3 copolymer containing from 4 to 10% by weight of C.sub.2 and exhibiting a M.F.R. from 35 to 45 g/10 minutes at 230.degree. C. and 2.16 kg;(c) 10-30% by weight of a C.sub.2 /C.sub.3 /(diene) elastomer containing from 40 to 55% by weight of C.sub.3 and from 0 to 5% by weight of a diene monomer, which is amorphous to X-rays and is characterized by:.alpha..sub.2 +.alpha..sub.4 higher than 16%R.sub.1 .times.R.sub.2 lower than 0.5M.W.D. lower than 3Mooney viscosity (ML 1+4, 100.degree. C.) from 30 to 38.vertline..eta..vertline. from 1.5 to 2 dl/g, measured in tetrahydronaphthalene at 135.degree. .

Abstract: This invention relates to plastoelastomeric polyolefinic compositions comprising an intimate mixture of the following components, in the indicated percentages by weight:(A) 10-50% of non cross-linked polypropylene;(B) 2-10% of ethylene/propylene/(diene) non cross-linked elastomeric copolymer,(C) 30-40% of polymeric product which is insoluble in xylene at 135.degree. C., comprising polypropylene and ethylene/propylene/(diene) copolymer, and(D) 5-58% of an extender oil.This invention also relates to a process for preparing the above compositions, which consists in subjecting to vulcanization under dynamic conditions a mixture comprising, in % by weight;(A) 20-80% of polypropylene;(B) 80-20% of ethylene/propylene/(diene) elastomeric copolymer,(C) 0.1-10%, referred to such copolymer, of a peroxide,(D) 5-60%, referred to such peroxide, of a furan derivative as a cross-linking coadjuvant.and in adding, after vulcanization, the extender oil in an amount ranging from 6 to 100% calculated on the vulcanized product.

Abstract: (1) Polymeric compositions, suitable for use as bitumen modifiers, comprising, by weight:(a) 20-50% of an ethylene/propylene elastomeric copolymer containing from 60 to 75% by weight of ethylene, and having a value of Mooney viscosity (ML 1+4) at 100.degree. C. higher than 5;(b) 0-25% of polypropylene prevailingly constituted by isotactic macromolecules having an M.I. value higher than 1;(c) 0-70% of substantially amorphous polypropylene, possibly in mixture with amorphous copolymers of ethylene with propylene, such component (c) having a total combined ethylene content lower than 60% by weight, and intrinsic viscosity (in tetralin at 135.degree. C.) lower than 2 dl/g;(d) 0-25% of polyethylene having density comprised between 0.98 and 0.96 g/cm.sup.3, and having a value of M.I. higher than 5;(e) 0-25% of an ethylene/vinyl acetate (EVA) copolymer containing from 60 to 95% by weight of ethylene, having a value of M.I. higher than 0.

Abstract: Ethylenically unsaturated monomers are grafted on homo- and olefinic co-polymers by means of a radicalic reaction, operating at between 60.degree. C. and 160.degree. C., in a solution of the polymer in a solving medium consisting of, or predominantly comprising a mixture of a component (A), chosen between aliphatic hydrocarbons, aromatic hydrocarbons, esters and ethers containing at least one aromatic or cycloaliphatic group, with a component (B) consisting of an aliphatic, cycloaliphatic or aromatic ketone, and by separating at the end of the reaction the grafted polymer, by means of the cooling down of the solution to a temperature below 40.degree. C.