Embodiments are directed to a catalyst system comprising metal-ligand complexes and processes for polyolefin polymerization using the metal-ligand complex having the following structure: ##STR00001##

Embodiments are directed to a catalyst system comprising metal-ligand complexes and processes for polyolefin polymerization using the metal-ligand complex having the following structure: ##STR00001##

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 tyre for wheels of vehicles, in particular motor vehicles, is described. The tyre has a tread with at least one iso-styrene/trans-butadiene elastomeric copolymer with a styrene content higher than 30% by weight with respect to the total weight of copolymer and a molecular weight higher than 500,000. The tread has improved dynamic-mechanical behaviour at high temperatures, with higher dynamic modulus and hysteresis values, and at the same time better properties at break, optimum elasticity at low temperature and higher abrasion resistance.

A tyre for wheels of vehicles, in particular motor vehicles, is described. The tyre has a tread with at least one iso-styrene/trans-butadiene elastomeric copolymer with a styrene content higher than 30% by weight with respect to the total weight of copolymer and a molecular weight higher than 500,000. The tread has improved dynamic-mechanical behaviour at high temperatures, with higher dynamic modulus and hysteresis values, and at the same time better properties at break, optimum elasticity at low temperature and higher abrasion resistance.

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.

Embodiments are directed to a catalyst system comprising metal ligand complexes and processes for polyolefin polymerization using the metal ligand complex having the following structure:

##STR00001##

Embodiments are directed to a catalyst system comprising metal ligand complexes and processes for polyolefin polymerization using the metal ligand complex having the following structure:

##STR00001##