A tyre for wheels of vehicles, in particular motor vehicles, is described. The tyre has a tread with at least one copolymer of (iso-styrene/trans-butadiene):diene-terminated copolymers. The tread has less sensitivity to the effects of temperature, with less weakness, better consistency of performances, and improved characteristics in terms of grip and/or resistance to laceration.

A (iso-styrene/trans-butadiene):diene-terminated copolymer is described which includes (i) a polymeric block of styrene-butadiene consisting of a random sequence of butadiene in trans conformation and styrene in isotactic configuration, and (ii) a terminal polymeric block consisting of a sequence of one or more dienic monomers.

A (iso-styrene/trans-butadiene):diene-terminated copolymer is described which includes (i) a polymeric block of styrene-butadiene consisting of a random sequence of butadiene in trans conformation and styrene in isotactic configuration, and (ii) a terminal polymeric block consisting of a sequence of one or more dienic monomers.

An iso-styrene:diene-terminated copolymer is described which includes (i) a polymeric block of styrene and/or substituted styrene consisting of a sequence of styrene and/or substituted styrene in isotactic configuration, and (ii) a terminal polymeric block consisting of a sequence of one or more dienic monomers.

An iso-styrene:diene-terminated copolymer is described which includes (i) a polymeric block of styrene and/or substituted styrene consisting of a sequence of styrene and/or substituted styrene in isotactic configuration, and (ii) a terminal polymeric block consisting of a sequence of one or more dienic monomers.

A method for producing an olefin block polymer, the method includes: polymerizing olefin using a polymerization catalyst (X), a polymerization catalyst (Y), and an organometallic compound (C) having an atom of any of Groups 2, 12, and 13 of the periodic table of the elements, the organometallic compound (C) excluding an activating co-catalyst agent (B), wherein: the polymerization catalyst (X) is formed by bringing a transition metal compound (A-X) represented by a general formula (1-X) into contact with an activating co-catalyst agent (B); and the polymerization catalyst (Y) is formed by bringing a transition metal compound (A-Y) represented by a general formula (1-Y) into contact with the activating co-catalyst agent (B). ##STR00001## [Chem. 2]
(ML.sub.aX.sub.bE.sub.c).sub.n(1-Y)

A method for producing an olefin block polymer, the method includes: polymerizing olefin using a polymerization catalyst (X), a polymerization catalyst (Y), and an organometallic compound (C) having an atom of any of Groups 2, 12, and 13 of the periodic table of the elements, the organometallic compound (C) excluding an activating co-catalyst agent (B), wherein: the polymerization catalyst (X) is formed by bringing a transition metal compound (A-X) represented by a general formula (1-X) into contact with an activating co-catalyst agent (B); and the polymerization catalyst (Y) is formed by bringing a transition metal compound (A-Y) represented by a general formula (1-Y) into contact with the activating co-catalyst agent (B). ##STR00001## [Chem. 2]
(ML.sub.aX.sub.bE.sub.c).sub.n(1-Y)

A method for producing an olefin block polymer, the method including: polymerizing olefins using a polymerization catalyst (X) and an organometallic compound (C) containing an atom of any of Groups 2, 12, and 13 of the periodic table of the elements, the organometallic compound (C) excluding an activating co-catalyst agent (B), wherein the polymerization catalyst (X) is formed by bringing a transition metal compound (A) into contact with the activating co-catalyst agent (B), the transition metal compound (A) is represented by the following general formula (1), and the activating co-catalyst agent (B) is selected from among an organoaluminumoxy compound (B-1), an organoboron compound (B-2), a zinc co-catalyst component (B-3), and ion-exchange layered silicate (B-4). ##STR00001##

A method for producing an olefin block polymer, the method including: polymerizing olefins using a polymerization catalyst (X) and an organometallic compound (C) containing an atom of any of Groups 2, 12, and 13 of the periodic table of the elements, the organometallic compound (C) excluding an activating co-catalyst agent (B), wherein the polymerization catalyst (X) is formed by bringing a transition metal compound (A) into contact with the activating co-catalyst agent (B), the transition metal compound (A) is represented by the following general formula (1), and the activating co-catalyst agent (B) is selected from among an organoaluminumoxy compound (B-1), an organoboron compound (B-2), a zinc co-catalyst component (B-3), and ion-exchange layered silicate (B-4). ##STR00001##