Abstract: The invention describes a cable with recyclable covering, particularly for transporting or distributing medium or high voltage energy, in which at least one covering layer is based on thermoplastic polymer material comprising a propylene homopolymer or a copolymer of propylene with ethylene or an &agr;-olefin other than propylene in mixture with a dielectric liquid. The cable of the invention possesses superior mechanical and electrical properties, including high dielectric strength, in particular enabling it to be used at high operating temperature.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components:

Abstract: Method for improving processability and storage stability of a silica filled elastomeric composition, said method comprising adding to said composition a thermoplastic polymer having a main hydrocarbon chain to which hydroxy groups are linked, said polymer having a weight-average molecular weight of at least 8,000. Preferably, the method further comprises adding to the silica filled elastomeric composition a polymer containing functional groups reactive with said hydroxy groups. The polymer containing hydroxy groups is highly effective in reducing and stabilizing viscosity of the composition, even when used in relatively low amounts, while maintaining or even enhancing the reinforcement effect of silica on the elastomeric composition. The resulting composition is particularly suitable to produce tyres, and particularly tyre treads.

Abstract: An elastomeric composition includes at least one elastomeric diene polymer, at least one thermoplastic polymer, and at least one polymer comprising functional groups. The at least one thermoplastic polymer comprises a main hydrocarbon chain. Hydrophilic groups are linked to the main hydrocarbon chain. The functional groups are reactive with the hydrophilic groups. The composition may also include at least one reinforcing filler. The at least one reinforcing filler may include carbon black, silica, or both carbon black and silica. The composition may further include a silica coupling agent, a sulfur-based vulcanizing agent, or both a silica coupling agent and a sulfur-based vulcanizing agent. A tire for vehicle wheels including at least one element including an elastomeric material, where the at least one element include the composition, is also disclosed.

Abstract: A flame-retardant composition includes a crystalline propylene homopolymer or copolymer, a copolymer of ethylene with at least one alpha-olefin having from 3 to 12 carbon atoms, and optionally with a diene, the copolymer of ethylene being characterized by a composition distribution index greater than 45%, the index being defined as a weight percentage of copolymer molecules having an alpha-olefin content within 50% of an average total molar content of alpha-olefin, and natural magnesium hydroxide in amounts such as to impart flame-retardant properties. A related cable with self-extinguishing properties includes a conductor and a flame-retardant coating. The flame-retardant coating includes the flame-retardant composition.

Abstract: A self-extinguishing cable and the flame-retardant composition used therein are disclosed. The cable comprises at least one flame-retardant coating comprising a) at least one polymer material; b) at least one inorganic hydrated flame-retardant filler; and c) at least one silane substituted with at least one C10-C40 hydrocarbon group and with at least one hydrolysable group. The self-extinguishing cable shows improved insulating properties in water or in the presence of a moist environment without adversely affecting self-extinguishing properties.

Abstract: A cable includes at least one conductor and at least one covering layer. The at least one covering layer includes a thermoplastic polymer material. The polymer material includes a propylene homopolymer or a copolymer of propylene with an olefin comonomer. The olefin comonomer is ethylene, one or more &agr;-olefins other than propylene, or ethylene and one or more &agr;-olefins other than propylene. The homopolymer or copolymer has a melting point between 140° C. and 165° C., a melting enthalpy between 30 J/g and 80 J/g, a boiling diethyl ether soluble fraction less than or equal to 12 wt % and melting enthalpy less than or equal to 4 J/g, a boiling n-heptane soluble fraction between 15 wt % and 60 wt % and melting enthalpy between 10 J/g and 40 J/g, and a boiling n-heptane insoluble fraction between 40 wt % and 85 wt % and melting enthalpy greater than or equal to 45 J/g.

Abstract: Cables, in particular electrical cables for low-voltage power transmission or for telecommunications, or alternatively for data transmission or mixed power/telecommunications cables, which have self-extinguishing properties and produce a low level of fumes, wherein a coating layer based on a polymer material and on a flame-retardant inorganic filler is present. The polymer material includes a heterophase copolymer having an elastomeric phase based on ethylene copolymerized with an &agr;-olefin and a thermoplastic phase based on propylene. The elastomeric phase is at least 45% by weight relative to the total weight of the heterophase copolymer and the heterophase copolymer is substantially devoid of crystallinity deriving from polyethylene sequences.

Abstract: A cable, in particular for power transmission, for telecommunications or for data transmission, or also combined power/telecommunications cables, wherein at least one coating layer consists of a recyclable material which is halogen-free and has superior mechanical, electrical, and flame-retardant properties. This material consists of a polymer mixture comprising: (a) a crystalline propylene homopolymer or copolymer; and (b) a copolymer of ethylene with at least one alpha-olefin having from 4 to 12 carbon atoms, and optionally with a diene; the said copolymer (b) being characterized by a density of between 0.90 and 0.86 g/cm3 and by a Composition Distribution Index, defined as the weight percentage of copolymer molecules having an alpha-olefin content within 50% of the average total molar content of alpha-olefin, of greater than 45%. This material may also include a flame-retardant inorganic filler.

Abstract: The invention describes a cable, in particular for electric energy transportation or distribution, in which an electrically insulating layer is present, consisting of a material substantially free of lead or derivatives thereof, and having high resistance to water.

Abstract: Process for preparing an electrical cable comprising at least one conductor and at least one layer of extruded insulating coating, which includes:

Abstract: Amorphous copolymers of ethylene with propylene, and optionally with minor amounts of polyenes, have the following characteristics: (A) the % content by mole of propylene in the copolymer (%P) and the triads ratio EPE/(EPE+PPE+PPP) satisfy the following relationship: 0.01%P+EPE/(E?E+PPE+PPP)≧1 (B) less than 2% of the CH2 groups in the chain are in sequences (CH2)n, wherein n is an even number. These copolymers are obtainable by operating in the presence of particular metallocene catalysts having two fluorenyl groups joined together through a bridging group.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components: (A) a porous organic support functionalised with groups having active hydrogen atoms; (B) an organo-metallic compound of aluminium containing heteroatoms selected from oxygen, nitrogen and sulphur; and (C) a compound of a transition metal selected from those of groups IVb, Vb or VIb of the Periodic Table of the Elements, containing ligands of the cyclopentadienyl type. These supported catalysts, obtainable in the form of spherical particles, can be used in the polymerization reaction of olefins either in liquid or in gas phase, thus producing polymers endowed with a controlled morphology and with a high bulk density.

Abstract: Supported catalysts for the polymerization of olefins comprise the following components: (A) a porous organic support functionalised with groups having active hydrogen atoms; (B) an organo-metallic compound of aluminium containing heteroatoms selected from oxygen, nitrogen and sulphur; and (C) a compound of a transition metal selected from those of groups IVb, Vb or VIb of the Periodic Table of the Elements, containing ligands of the cyclopentadienyl type. These supported catalysts, obtainable in the form of spherical particles, can be used in the polymerization reaction of olefins either in liquid or in gas phase, thus producing polymers endowed with a controlled morphology and with a high bulk density.

Abstract: A cable, in particular for power transmission, for telecommunications or for data transmission, or also combined power/telecommunications cables, wherein at least one coating layer consists of a recyclable material which is halogen-free and has superior mechanical, electrical, and flame-retardant properties. This material consists of a polymer mixture comprising: (a) a crystalline propylene homopolymer or copolymer; and (b) a copolymer of ethylene with at least one alpha-olefin having from 4 to 12 carbon atoms, and optionally with a diene; the said copolymer (b) being characterized by a density of between 0.90 and 0.86 g/cm3 and by a Composition Distribution Index, defined as the weight percentage of copolymer molecules having an alpha-olefin content within 50% of the average total molar content of alpha-olefin, of greater than 45%. This material may also include a flame-retardant inorganic filler.

Abstract: A process for the preparation of amorphous copolymers of ethylene with &agr;-olefins and optionally minor amounts of polyenes are disclosed, which have the following characteristics: (A) the % by mole content of &agr;-olefin in the copolymer (%&agr;) and the ratio between the molar amount of &agr;-olefin diads and the molar content of &agr;-olefin in the copolymer (&agr;&agr;/&agr;) satisfy the following relationship: (%&agr;)−250 (&agr;&agr;/&agr;)≧10 (B) less than 2% of the CH2 groups in the polymeric chain are in sequences (CH2)n, wherein n is an even number. These copolymers are obtained by operating in the presence of particular metallocene-based catalysts having two fluorenyl groups joined together through a bridging group.

Abstract: A cable, in particular for power transmission, for telecommunications or for data transmission, or also combined power/telecommunications cables, wherein at least one coating layer is comprised of a recyclable material which is halogen-free and has superior mechanical and electrical properties. This material comprises a polymer mixture of a crystalline propylene homopolymer or copolymer and an elastomeric copolymer of ethylene with at least one alpha-olefin having from 3 to 12 carbon atoms, and optionally containing a diene. The copolymer is characterized by a 200% tension set value of lower than 30% (measured at 20° C. for 1 minute according to ASTM standard D 412). The cable also includes a flame-retardant polymer composition.

Abstract: Cable, in particular for medium-voltage or high-voltage electrical power transmission or distribution, for telecommunications or for data transmission, comprising a conductor and at least one coating layer based on a non-crosslinked polymer material comprising a heterogeneous copolymer with an ethylene-based elastomeric phase copolymerized with an &agr;-olefin and a propylene-based thermoplastic phase, in which the said elastomeric phase in the said heterogeneous copolymer is at least 45% by weight relative to the total weight of the heterogeneous copolymer, and the said heterogeneous copolymer is essentially free of crystallinity deriving from polyethylene sequences.

Abstract: Novel crystalline copolymers of propylene with minor proportions of ethylene and/or alpha-olefins, endowed with very good mechanical properties, a low melting point and a limited solubility in xylene at 25° C., and the process for preparing them by means of the polymerization of mixtures of propylene with ethylene and/or alpha-olefins of suitable composition, by using catalysts obtained from stereorigid and chiral compounds of zirconium, and methylalumoxanic compounds.

Abstract: Self-extinguishing cable coated with a flame-retardant composition having: (a) an ethylene homopolymer or copolymer having a density of from 0.905 to 0.970 g/cm3, and being selected from: ethylene homopolymers: copolymers of ethylene with an alpha-olefin; copolymers of ethylene with an ethylenically unsaturated ester; or mixtures thereof; (b) a copolymer of ethylene with at least one alpha-olefin, and optionally with a diene, said copolymer (b) having a density of from 0.860 to 0.904 g/cm3, and having a composition distribution index greater than 45%; (c) natural magnesium hydroxide in an amount such as to impart flame-retardant properties; wherein at least one of the polymeric components (a) and (b) contains hydrolyzable organic silane groups grafted onto the polymer chain. The silane groups are preferably introduced during compounding of the flame-retardant composition by adding to the polymer mixture a suitable silane compound and a radical initiator.