Abstract: A cable having at least one electrical conductor and at least one extruded covering layer based on a thermoplastic polymer material in admixture with a dielectric liquid. The thermoplastic polymer material is selected from: (a) at least one propylene homopolymer or at least one copolymer of propylene with at least one olefin comonomer; (b) a mechanical mixture of at least one propylene homopolymer or copolymer (a) and (c) at least one elastomeric copolymer or ethylene with at least one aliphatic ?-olefin, and optionally a polyene. The cable of the invention possesses good mechanical and electrical properties, including high dielectric strength, in particular enabling it to be used at high operating temperature.

Abstract: An electrical cable having at least one conductor and at least one extruded insulating coating layer. The extruded insulating coating layer includes a polymeric composition having a polyethylene grafted with at least one unsaturated carboxylic acid of general formula (I): in which: R represents H or CH3; n represents 0 or 1. The grafted polyethylene is derived from polyethylene, a radical initiator and at least one unsaturated carboxylic acid of general formula (I) in free form; and the unsaturated carboxylic acid is present in an amount of between 0.0006% and 0.25% by weight. The amount is expressed as the weight content of —COOH groups relative to the total weight of the polymeric composition.

Abstract: Electrical cable particularly for high voltage direct current transmission having at least once conductor and at least one extruded insulating coating layer of a polymeric composition. The polymeric composition is a polyethylene modified with at least one compound of formula (I): in which R represents H or CH3; R1 represents a linear or branched, preferably linear, C1-C8 alkylene group; R2 represents OH; a group OR3 in which R3 represents a linear or branched C1-C4 alkyl group, a group NR4R5 in which R4 and R5, which may be identical or different, represent H, or a linear or branched C1-C4 alkyl group, and related insulating composition.

Abstract: Process for preparing an electrical cable comprising at least one conductor and at least one layer of extruded insulating coating, which includes: coating, by extrusion, the conductor with a polymeric composition comprising a polyethylene, a radical initiator and at least one unsaturated carboxylic acid of general formula (I) in free form: ?in which: R represents H or CH3; n represents 0 or 1; ?said unsaturated carboxylic acid being present in an amount of between 0.0006% and 0.25% by weight, said amount being expressed as the weight content of —COOH groups relative to the total weight of the polymeric composition; heating the conductor thus coated so as to obtain cross-linking of said polymeric composition.

Abstract: Process for preparing an electrical cable comprising at least one conductor and at least one layer of extruded insulating coating, which includes: coating, by extrusion, the conductor with a polymeric composition comprising a polyethylene, a radical initiator and at least one unsaturated carboxylic acid of general formula (I) in free form: in which: R1 represents H or CH3; n represents 0 or 1; said unsaturated carboxylic acid being present in an amount of between 0.0006% and 0.25% by weight, said amount being expressed as the weight content of —COOH groups relative to the total weight of the polymeric composition; heating the conductor thus coated so as to obtain cross-linking of said polymeric composition.

Abstract: Electrical cable particularly for high voltage direct current transmission having at least once conductor and at least one extruded insulating coating layer of a polymeric composition.

Abstract: Cable for high voltage direct current transmission having at least one conductor and at least one extruded insulating layer consisting of a polymeric composition of a polyethylene and at least one unsaturated fatty acid. Insulating composition having a polyethylene and at least one unsaturated fatty acid.

Abstract: Biodegradable thermoplastic compositions comprising a starch component, a cellulose ester or ether, a plasticizer for the starchy phase and of the cellulose and derivatives, and a compatibilizer agent selected from polymers compatible with the cellulose and or starchy component, grafted with aliphatic or polyhydroxilated chains; copolymers obtained from hydroxy acids and/or diamines with 2-24C and aliphatic or aromatic diisocyanates; copolymers obtained from aliphatic polyesters, polyureas and polyalkylene glycols and aliphatic or aromatic diisocyanates; copolymers obtained from polymers compatible with cellulose ester or ethers and/or the starchy component by grafting starch soluble polyols; polymer capable of complexing starch; starch compatible polyols.

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

Abstract: A method for increasing the molecular weight of aliphatic polyester resins from dicarboxylic aliphatic acids having 2-22 carbon atoms, or from hydroxy-acids having 2-22 carbon atoms, in which the solid resin is brought into contact with a chain extender preferably chosen from the organic disocyaciates.

Abstract: A synthetic material is disclosed, which is constituted by a copolymer of D, L-lactide and &egr;-caprolactone (which itself is characterized by lower degradation times than those obtainable with copolymers of L-lactic acid and &egr;-caprolactone), obtained by using as reaction control agent a sugar dianhyide with non-toxic characteristics. The use of suar dianhydrde in the reaction has a considerable control effect on the molecular weight of the copolymer and, thanks to its low molecular weight, this copolymer is characterized by extreraely short resorption times, in the order for the example of one or two months. The copolymer is used as covering clement to be placed around tendon sutures and/or nerve tracts with the aim of preventing formation of scarry adherences between the suture lines and the soft surrounding tissues.

Abstract: A process of surface activation of a material based on one or more of the copolymers of lactic acid and .epsilon.-caprolactone is carried out on bioabsorbable and biocompatible aliphatic polyesters chosen from the group formed by homo- and copolymers derived from L-lactide, D-lactide, racemic D,L-lactide, meso D,L Lactide, .epsilon.-caprolactone, glycolide, .delta.-valerolactone, p-dioxanone, preferably copolymers of L-lactide, D-lactide, racemic D,L lactide, meso D,L-lactide with .epsilon.-caprolactone; the process consists of performing at least one of the following treatments: acid or base hydrolysis, treatment by means of cold plasma, by chemical reactions or electromagnetic radiations.The process brings about a substantial increase in surface hydrophilicity and, consequently, a significant lowering of the wetting angle measured with water at 23 degrees Celsius in air.

Abstract: Poly(lactic acid) with a high molecular weight is produced by the polycondensation reaction of the free monomer carried out in the presence of a catalytically effective quantity of iron ions. High molecular weight poly(lactic acid) and lactide are obtained as the principal products.

Abstract: Polymers and copolymers of L(+) and D(-) lactic acid, with high molecular weight and in the absence of catalysts, are prepared by upgrading low molecular weight polymers in the solid state.

Abstract: New chlorotrifluoroethylene telomers and process for preparing them. Chlorotrifluoroethylene is reacted, at a temperature ranging from -100.degree. to +40.degree. C., with a fluoroxy compound of formula R.sub.x --CF.sub.2 OF, wherein R.sub.x represents among others a perhalogenated alkyl radical containing from 1 to 10 carbon atoms. There are obtained telomer mixtures having, among others, the following formulae: R.sub.x --CF.sub.2 --O--(M).sub.n --F; R.sub.x --CF.sub.2 --O--(M).sub.n --O--CF.sub.2 --R.sub.x ; R.sub.x --(M).sub.n --F; R.sub.x (M).sub.n --R.sub.x ; R.sub.x --CF.sub.2 --O--(M).sub.n --R.sub.x and F--(M).sub.n --F; wherein M is CF.sub.2 --CFCL and "N" ranges from 2 to 20. Most of these telomers are new compounds.

Abstract: Preparation of fluorooxy-fluorosulfonyl-fluorocompounds by means of the direct fluorination with elemental fluorine of various .beta.-sultones according to the following reaction scheme: ##STR1## wherein R.sub.1 and R.sub.2, which can be either equal to, or different from, each other, represent a fluorine or chlorine atom, or an alkyl radical partially or totally halogenated with fluorine and/or chlorine.The reaction takes place in continuous in the presence of a fluorination catalyst, preferably constituted by an alkali-metal fluoride preferably supported on a metal material, at temperatures comprised within the range of from -30.degree. C. to +100.degree. C., and under the pressure comprised within the range of from 50 to 800 kPa; said catalyst is a fixed-bed catalyst, or is suspended in a reaction medium inert under the operating conditions.