Abstract: The invention relates to compositions for cables filling wherein a styrene-butadiene block copolymer with radial structure is used as a gelling agent. This polymer is obtained through styrene and butadiene sequential polymerization and subsequent reaction with a coupling agent preferably of type Cl4-nMRn, wherein M=Sn or Si, R is an alkyl or aryl group and n is an integer from 0 to 2, and hydrogenation of the resulting polymer. This type of copolymer brings a higher stability to the final properties of the gel as compared with the linear hydrogenated synthetic rubbers usually used in the prior art.

Abstract: Procedure for the preparation of aromatic derivatives of titanocene, useful as catalysts for the polymerisation and hydrogenation of polymers, characterised by the use of a Grignard reagent. This procedure allows to easily prepare compounds with the general formula where: L, which can be equal to or different one from the other, are cyclopentadiene, or pentamethylcyclopentadiene; preferably at least one L is cyclopentadiene; R1, R2, R3, equal or different from one another, are selected from the group consisting of: hydrogen, alkyl group from 1 to 4 carbon atoms, OR4 where R4 is an alkyl group of 1 to 4 carbon atoms; at least one of the R1, R2 or R3 is hydrogen. The preparation is carried out by the reaction of the titanocene dichloride with the corresponding Grignard reagent. This method substantially enhances safety, reproducibility, yield and cost of that carried out via lithium compounds.

Abstract: The invention relates to compositions for cables filling wherein a styrene-butadiene block copolymer with radial structure is used as a gelling agent. This polymer is obtained through styrene and butadiene sequential polymerization and subsequent reaction with a coupling agent preferably of type Cl4-nMRn, wherein M=Sn or Si, R is an alkyl or aryl group and n is an integer from 0 to 2, and hydrogenation of the resulting polymer. This type of copolymer brings a higher stability to the final properties of the gel as compared with the linear hydrogenated synthetic rubbers usually used in the prior art.

Abstract: Process for producing hydrogenated rubbers which allows an easy and effective deactivation of the living polymer before the hydrogenation step. The deactivation of living polymer is carried out using compounds with very good solubility in water of formula R--OH, R--COOH or compound of type R'.sub.n --Si--Cl.sub.4-n, R'.sub.n --Sn--Cl.sub.4-n, with n comprised between 0 and 3, extremes included; wherein R is a C.sub.2 -C.sub.20 alkyl group optionally containing one or more polar functional groups selected from C--OH, COOH, and R' is a C.sub.1 -C.sub.20 alkyl or C.sub.6 -C.sub.20 aryl. The catalysts used in the hydrogenation of the deactivated polymer are titanocene compounds, being the most preferred those of formula Cp.sub.2 Ti (PhOCH.sub.3).sub.2 and Cp.sub.2 Ti (CH.sub.2 PPh.sub.2).sub.2.

Abstract: Procedure of olefin hydrogenation in liquid phase in the presence of homogeneous catalysts that contain, as essential component, a titanocene of general formula Cp CpTiR.sub.2, Cp CpTiR.sub.2, Cp Cp[CpTiR.sub.2 ].sub.2, or Cp Cp[Cp TiR.sub.2 ].sub.2 where Cp is a pentamethylcyclopentadienyl, Cp cyclopentadienyl, Cp Cp are two cyclopentadienyl rings linked together by a dimethylsililene (Me.sub.2 Si), and R is an alyl, aryl, alkylaryl, or alcoxide group containing between 1 and 20 carbon atoms or a halogen atom, a PPh.sub.2, CH.sub.2 SiMe.sub.3, CH.sub.2 PPh.sub.2, or H.These catalysts are very active in the hydrogenation of linear and branched, internal and external olefins, cycloolefins and diolefins.