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.

The present disclosure provides a process. The process includes (i) forming a composition containing a peroxide-modified ethylene-based polymer selected from the group consisting of a peroxide-modified ethylene/a-olefin multi-block copolymer, a peroxide-modified low density polyethylene, and combinations thereof; (ii) contacting the composition with a blowing agent to form a foam composition; and (iii) forming foam beads comprising the foam composition. The present disclosure also provides a foam bead produced by said process.

The present invention relates to a solid catalyst for propylene polymerization and a method of producing a propylene polymer or copolymer using the solid catalyst for propylene polymerization, and provides a solid catalyst which prepares a dialkoxymagnesium carrier and is formed of a carrier produced through a reaction of the carrier with a metal halide, a titanium halide, an organic electron donor, etc., and a method of producing a propylene polymer or copolymer through copolymerization of propylene-alpha olefin using the solid catalyst, wherein the dialkoxymagnesium carrier has an uniform particle size range of 10 to 100 m and a spherical particle shape by adjusting injection amounts, injection numbers, and reaction temperatures of metal magnesium, alcohol and a reaction initiator during a reaction process of metal magnesium and alcohol.

The invention provides a polyolefin composition comprising: (i) 55 to 95 wt % of a propylene butene random copolymer having an MFR.sub.2 of 1.0 to 20.0 g/10 min, a butene content of 1.5 to 8.0 wt % and prepared using a single site catalyst; and (ii) to 45 wt % of an ethylene based plastomer having a density of 860 to 905 kg/m.sup.3, an MFR.sub.2 of 0.3 to 30 g/10 min and prepared using a single site catalyst.

The present disclosure relates to a catalyst system for use in forming a multi-block copolymer, said copolymer containing therein two or more segments or blocks differing in chemical or physical properties, a polymerization process using the same, and the resulting polymers, wherein the composition comprises the admixture or reaction product resulting from combining: (A) a first olefin polymerization procatalyst, (B) a second olefin polymerization procatalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by procatalyst (A) under equivalent polymerization conditions, (C) an activator, and (D) a chain shuttling agent.

A process for preparing a multiblock polymer by statistical copolymerization of a mixture containing ethylene and a 1,3-diene and subsequent polymerization of ethylene in the presence of a rare-earth metallocene and an organomagnesium reagent R.sup.B(MgR.sup.A).sub.mMgR.sup.B or XMgR.sup.AMgX is provided. According to the formula, R.sup.A is a divalent aliphatic hydrocarbon-based chain optionally interrupted with one or more oxygen or sulfur atoms or arylene groups, R.sup.B comprises a benzene nucleus substituted with the Mg atom, one of the carbon atoms of the benzene nucleus ortho to the Mg is substituted with a methyl, an ethyl or an isopropyl or forms a ring with the carbon atom which is its closest neighbour and which is meta to the Mg. The other carbon atom of the benzene nucleus ortho to the Mg is substituted with a methyl, ethyl or isopropyl, X being a halogen atom, m being greater than or equal to 1.

A block copolymer composition is disclosed. The composition contains an elastomeric block copolymer and a hydrophilic fumed silica with a surface area (BET, measured by nitrogen gas adsorption) of at least 200 m.sup.2/g, and a pH of 3 to 5, a tamped density of <=75 g/L. The block copolymer composition forms free-flowing composition, requiring less than 400 lbs/ft.sup.2 to break in a blocking test. The free-flowing composition does not negatively impact haze, transparency, and yellowness of transparent compounds, suitable for use in transparent formulations for medical, toys, and overmolds, viscosified oils, and oil gels applications.

The present invention relates to an organic zinc compound comprising a styrene-based polymer or a polyolefin-polystyrene block copolymer at both ends. Also, the present invention relates to a method for preparing the organic zinc compound, the method preparing an intermediate by coordination-polymerizing an olefin monomer using a transition metal catalyst, and then performing anionic polymerization by inserting an alkyllithium compound, an amine ligand, and a styrene-based monomer into the intermediate. Accordingly, the present invention can provide a method for preparing a commercially useful styrene-based polymer or polyolefin-polystyrene block copolymer directly from an olefin monomer and a styrene monomer in a one-pot manner.

A polymer composition and a process for the production of this composition comprising a base resin is disclosed herein. The base resin includes a very high molecular weight component, a low molecular weight component, and a high molecular weight component having a weight average molecular weight higher than the weight average molecular weight of the low molecular weight component but lower than the weight average molecular weight of the very high molecular weight component. An amount of the very high molecular weight component in the base resin is 0.5 to 8 wt %. The very high molecular weight component has a viscosity average molecular weight of greater than 1100 kg/mol. The composition has FRR.sub.21/5 of equal to or greater than 38, a melt flow rate MFR.sub.21 of equal to or greater than 6.5 g/10 min and a viscosity at a shear stress of 747 Pa (eta747) of 450 to 3000 kPas.

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 consistancy of performances, and improved characteristics in terms of grip and/or resistance to laceration.