Abstract: Catalyst components for the polymerization of olefins and catalysts obtained therefrom, said components comprising a porous metal oxide on which a magnesium dihalide, and a titanium halide or titanium halogen alcoholate and a compound containing two or more ether groups having specific reactivity properties towards MgCl.sub.2 and TiCl.sub.4 are supported.

Abstract: Disclosed are solid catalyst components for the polymerization of olefins comprising a titanium halide or titanium alkoxy halide, and an electron-donor compound selected from silicon compounds of the formula ##STR1## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are hydrocarbyl radicals, supported on a magnesium halide in active form.Also disclosed are catalysts obtained from said catalyst components and from an Al-alkyl compound, as well as catalysts obtained by the reaction of an Al-alkyl compound and a silicon compound of the formula above with a solid catalyst component comprising a titanium halide or halogen alcoholate and an electron-donor compound having specific characteristics of extractability with Al-triethyl, supported on an active magnesium halide.

Abstract: Compatible mixtures of styrene copolymers of type SAN (AES, ABS, SAN) with polyglutarimides, characterized in that the polyglutarimides are prepared by imidization of poly(meth)acrylates and/or poly(meth)acrylic acid with amides of formulaX--Z--NHRwhereX=H, hydrocarbyl or, when ##STR1## a --NHR radical or a --Y--CO--NHR radical; R=aryl; ##STR2## --C.sub.6 H.sub.4 --SO.sub.2. The mixtures composed of SAN copolymers and N-aryl polyglutarimides having a Tg of at least 140.degree. C. are claimed as new mixtures.

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: Crystalline copolymers of ethylene and alpha-olefins CH.sub.2 .dbd.CHR in which R is an alkyl group having 2 to 8 carbon atoms, containing 0.5 to 3% by moles of polymerized alpha-olefin and having a density lower than 0.945 g/cc are obtained by polymerizing, in the gas phase, mixtures of ethylene and the alpha-olefins in contact with catalysts prepared from (1) Ti compounds supported on Mg halides and (2) organometallic compounds, which are active in the polymerization of ethylene but exhibit little, if any, activity in the homo- or copolymerization of the alpha-olefins.

Abstract: Catalysts for the polymerization of olefins, obtained by means of the reaction of:a) a compound of a transition metal containing at least one metal-halogen linkage, supported on a magnesium halide in the active form, withb) a compound of Ti, Zr or Hf, containing at least one metal-carbon linkage.

Abstract: Catalyst components for the polymerization of olefins comprising a titanium halide or alkoxyhalide and an electron-donor compound selected from ethers having two or more ether groups and containing at least one heteroatom selected from the group consisting of N, S, P, Si, non-ether O and halogen atoms or at least one double bond, or both at least one heteroatom and at least one double bond, supported on a magnesium halide in active form.Catalysts obtained from said catalyst components and an Al-alkyl compound, as well as catalysts obtained by the reaction of an Al-alkyl compound and an ether having the above defined characteristics with a solid catalyst component comprising a titanium halide or alkoxyhalide and an electron-donor compound having particular characteristics of extractability with Al-triethyl, supported on activated magnesium halide.

Abstract: Catalysts for the polymerization of olefins, obtained from special zirconocenic compounds and from alkyl-Al compounds.

Abstract: Imidized acrylic polymers obtained by means of the reaction of an acrylic resin in the molten state, with at least one modifying agent having the general formula:R--X--NH--R' (I)wherein:R and R' are either equal to, or different from, each other and represent hydrogen or an alkyl, cycloalkyl, aryl or alkylaryl radical containing from 1 to 20 carbon atoms, andX is a bifunctional radical selected from the group consisting of: --CO--, --CONH--, --NHCO--, --OCO--, --SO.sub.2 --, --C.sub.6 H.sub.4 SO.sub.2 --.

Abstract: Disclosed is a component for a catalyst for the polymerization of alpha-olefins to stereoregular polymers having narrow molecular weight distribution. The product is formed by the reaction of a solid catalyst-forming component comprising (1) a Ti compound having at least one Ti-halogen bond and (2) optionally, an electron-donor compound, supported on an anhydrous Mg dihalide in active form, with certain amounts of an organic compound (AH) containing at least one active hydrogen atom, in the presence of a liquid medium which is inert with respect to the Ti compound and the other components of the catalyst component, and which has a dielectric constant greater than 2 at 20.degree. C.Catalysts comprising the reaction product of the solid catalyst component prepared as above described, with an Al-alkyl compound and an electron-donor compound are also disclosed.

Abstract: Catalysts for the polymerization of olefins, particularly alpha-olefin of the formula CH.sub.2 .dbd.CHR in which R is an alkyl radical with 1-6 carbon atoms or an aryl radical, obtained by the reaction of:(a) an Al-alkyl compound;(b) an ether containing at least two ether groups which can form complexes with anhydrous magnesium dichloride, under standard conditions of reaction, in an amount less than 60 mmol per 100 g Mg dichloride; and(c) a solid catalyst component comprising an anhydrous magnesium dihalide in active form and having supported thereon a titanium compound containing at least a Ti-halogen bond and an electron-donor compound which is at least 70 mole % extractable with Al-triethyl, under standard conditions of extraction, component wherein the solid, after extraction, has a surface area of more than 20 m.sup.2 g.

Abstract: Solid catalyst components for the polymerization of olefins and modified with electron-donor compounds, comprising a titanium halide supported on a magnesium dihalide in active form and containing as an electron-donor compound a di- or other polyether having specific reactivity characteristics towards MgCl.sub.2 and TiCl.sub.4.

Abstract: Imidized acrylic polymers obtained by means of the reaction of an acrylic resin in the molten state, with at least one modifying agent having the general formula:R--X--NH--R' (I)wherein:R and R' are either equal to, or different from, each other and represent hydrogen or an alkyl, cycloalkyl; aryl or alkylaryl radical containing from 1 to 20 carbon atoms, andX is a bifunctional radical selected from the group consisting of: --CO--, --CONH--, --NHCO--, --OCO--, --SO.sub.2 --, --C.sub.6 H.sub.4 SO.sub.2 --.

Abstract: Compositions comprising from 5 to 50% by weight of a polyphenylene ether and from 95 to 50% by weight of a styrene polymer having a syndiotactic structure. Such compositions are endowed with enhanced mechanical properties compared to those containing amorphous polystyrene, or polystyrene having an isotactic structure.

Abstract: Process for the imidization of vinyl-aromatic copolymers containing maleic anhydride, using as an imidizing agent an amide, the imidization being conducted in an anhydrous state and in the presence of a catalyst.

Abstract: Catalysts for the polymerization of alpha-olefins, which comprise the product of the reaction between:(a) a metallorganic compound of Al;(b) an electron-donor compound reactive towards MgCl.sub.2 but which is not completely complexed with AlEt.sub.3, at the equivalent point of a potentiometric titration under standard conditions;(c) a solid comprising a halogenated Ti compound and an electron-donor belonging to particular classes of compounds and being extractable with AlEt.sub.3 for at least 70% by mols from the solid, the surface area of which after extraction is higher than 20 m.sup.2 /g.The present invention refers to new supported components of catalysts for the polymerization of olefins CH.sub.2 .dbd.CHR, in which R is an alkyl with 1-4 carbon atoms or an aryl, and of mixtures of such olefins with each other and/or with ethylene, and to the catalysts obtained from such components.

Abstract: The invention concerns a process for the imidization of copolymers of maleic anhydride with vinyl-aromatic monomers using an urea as the imidizing agent.

Abstract: Solid components of catalysts for the (co)polymerization of ethylene, or precursors of such components are prepared by treating an (a) emulsion in a perfluoropolyether of a liquid compound of magnesium, of titanium or of another transition metal, or of solutions thereof, possibly using an electron-donor compound, with (b) a reducing and/or halogenating agent capable of forming an insoluble solid product, after which, if such a product is a precursor of the catalytic component, it is treated with a tetravalent-titanium halide, or with a halide of another transition metal.

Abstract: A process for preparing spheroid particles of oxide compounds, having an average diameter of smaller than 3 microns. An emulsion is prepared of a hydrolyzable liquid oxide compound in a perfluoropolyether, the emulsion is reacted with water, water vapor or with a mixture, in any ratio, of water with a liquid miscible or immiscible with water so as to form an oxide hydrate which is recovered dried and calcined. Oxide compounds include oxides of Ti, Al, Zr, Si or B.

Abstract: Polymers of alpha-olefins of formulaR--CH.dbd.CH.sub.2wherein R=alkyl of from 1 to 6 C atoms, or of their mixtures with minor amounts of ethylene are obtained by adopting catalysts comprising:(A) a solid component obtained by treating an emulsion (a) in a perfluoropolyether liquid of a liquid compound of magnesium, of titanium or of another transition metal, either liquid or in solution, with possibly using an electron-donor compound, with (b) a reducing and/or halogenating agent capable of forming an insoluble solid product, after which, if such a product is a precursor of the catalytic components, it is treated with a tetravalent-titanium halide, or with a halide of another transition metal;(B) an aluminum-alkyl compound;(C) an outer electron-donor compound (c).