Abstract: A process for producing a 1-butene polymer comprising the step of polymerizing 1-butene in the presence of a catalyst system obtainable by contacting: b) at least a metallocene compound of formula (Ia) in the meso or meso-like form: wherein M is an atom of a transition metal p is an integer from 0 to 3, X, same or different, is a hydrogen atom, a halogen atom, or a hydrocarbon group.

Abstract: Butene-1 (co)polymers characterized by the following properties: content of butene-1 units in the form of isotactic pentads (mmmm) from 25 to 55%; intrinsic viscosity [?] measured in tetraline at 135° C. from 1 to 3 dL/g; content of xylene insoluble fraction at 0° C. from 3 to 60%; and a ratio ES2/ES1>1, where ES1 is the boiling diethyl ether soluble fraction determined on the polymer as such and ES2 is the boiling diethyl ether soluble fraction determined after milling the polymer. The butene-1 (co)polymers show a good balance between processability and elastomeric behavior.

Abstract: A 1-butene polymer optionally containing from 0 to 30% by mol of derived units of ethylene, propylene or alpha-olefin of formula CH2?CHZ, wherein Z is a C3-C20 linear or branched alkyl radical, having the following features: a) distribution of molecular weight (Mw/Mn) lower than 4; b) Melt flow rate (MFR) measured according to ISO 1133 (190° C., 2.16 kg); c) Intrinsic viscosity (IV) measured in tetrahydronaftalene (THN) at 135° C. lower than 0.8 dl/g; d) melting point higher than 100° C.; e) isotactic pentads (mmmm) measured with 13C-NMR operating at 100.61 MHz higher than 90%; f) 4,1 insertions not detectable at a C13-NMR operating at 100.61 MHz; and g) a yellowness index lower than 0.

Abstract: A solution process for polymerizing one or more ?-olefins of the formula CH2?CHR, where R is H or an alkyl radical C1-C18, to produce a polymer that is soluble in the reaction medium, comprising the steps of: continuously polymerizing in a liquid phase the ?-olefin in the presence of a catalyst system based on a transition metal compound to obtain a solution of polymer in the reaction medium; the polymeric solution obtained from step a) is then mixed in one or more mixing stages with an aqueous mixture comprising one or more organic compounds having at least a hydroxy or epoxy group, said aqueous mixture having a dynamic viscosity at 30° C. higher than 50 cP (centiPoise).

Abstract: A multistage process comprising the following steps: a) polymerizing propylene with optionally one or more monomers selected from ethylene and alpha olefins of formula CH2?CHT1, wherein T1 is a C2-C20 alkyl radical in the presence of a catalysts system, supported on an inert carrier comprising: i) a transition metal compound containing a ligand having a cyclopentadienyl skeleton; and ii) an alumoxane or a compound capable of forming an alkyl metallocene cation; b) contacting, under polymerization conditions, in a gas phase, ethylene with one or more alpha olefins of formula CH2?CHT1, wherein T1 is a C2-C20 alkyl radical, and optionally a non-conjugated diene, in the presence of the polymer obtained in step a), in the presence of a weigh ratio hydrogen/hethylene higher than 1 ppm and optionally in the presence of an additional organo aluminum compound; wherein the amount of the polymer obtained in step a) ranges from 5% by weight and 90% by weight of the polymer obtained in the whole process and the amount of

Abstract: A process for polymerizing one or more alpha-olefins of formula CH2?CHT wherein T is a hydrogen atom or a C1-C20 alkyl radical comprising the following steps: a) contacting in a continuous way one or more of said alpha olefins with a metallocene based catalyst system in a loop reactor, wherein: (i) the reaction is carried out in a liquid medium; (ii) the average residence time of the metallocene-based catalyst system is not more than 30 minutes; (iii) the temperature of the loop ranges from 25° to 70° C.; in to obtain a polymerization degree ranging from 60 to 500 g per gram of catalyst system; b) feeding in continuous the prepolymerized metallocene-based catalyst system obtained in step a) into a polymerization reactor C) polymerizing one or more alpha-olefins, the same or different from the alpha olefins used in step a), in the presence of said prepolymerized metallocene-based catalyst system.