A copolymer of ethylene and of a 1,3-diene of formula CH.sub.2CRCHCH.sub.2 is provided. The ethylene units represent between 50 mol % and 95 mol % of the ethylene units and of the units of the 1,3-diene, and the units of the 1,3-diene of 1,2 and 3,4 configuration represent more than 50 mol % of the units of the 1,3-diene. The symbol R represents a hydrocarbon chain having from 3 to 20 carbon atoms. Such a copolymer exhibits an improved compromise between the degree of crystallinity and the stiffness and makes it possible to widen the field of application of ethylene-rich diene copolymers in rubber compositions.

A thermoplastic vulcanizate comprises an isotactic polypropylene matrix phase in which cross-linked rubber particles are dispersed, the rubber particles comprising an ethylene-propylene-diene terpolymer (EPDM) containing at least 40 wt % of ethylene-derived units. A propylene-ethylene-diene terpolymer (PEDM) containing at least 60 wt % propylene-derived units and less than or equal to 25 wt % of ethylene-derived units and having a heat of fusion (H.sub.f) of 2 to 10 J/g is added to compatibilize the propylene/EPDM blend.

The invention relates to isoprene and butadiene and/or pentadiene stereoblock copolymers in which the different stereoregular blocks, joined to each other by means of a single junction point, have different structures and thermal properties. The invention also relates to a process for the preparation of the aforesaid copolymers which comprises the formation of stereoblocks in successive steps but in the presence of a single catalytic system obtained from cobalt dichloride, a phosphine and an organic compound of aluminum.

The disclosure relates to methods for producing poly(cyclohexadiene) homopolymers (PCHD). The PCHD is formed by polymerizing a 1,3-cyclohexadiene monomer in the presence of a catalyst, in a hydrocarbon solvent, and at a temperature of 100 C. to 120 C. The catalyst is selected from the group consisting of a Bronsted acid, a Lewis acid, and combinations thereof. PCHD produced under these conditions has good solubility in non-polar solvents, and a number average molecular weight of 300 to 5,000 Dalton; a weight average molecular weight of 5,000 to 15,000 Delton; and a polydispersity index of 3.0 to 8.0. The PCHD is useful for producing crosslinked materials having good physical properties. The crosslinked materials can be combined with a rubbery polymer to produce compositions valuable for further downstream uses.

An adhesive composition made from an elastomer and a tackifying resin. The tackifying resin includes a farnesene polymer or copolymer having the following properties: i) less than 10 weight percent of volatile organic compounds; ii) Mn between 300 Da and 1000 Da; iii) Mw between 400 Da and 3000 Da; iv) Mw/Mn between 1.00 and 3.00; v) Tg between 50 C. and 20 C.; and vi) viscosity between 400,000 cP and 1,000,000 cP at 25 C. A method of making the farnesene-based polymer or copolymer includes combining a farnesene monomer and a solvent and optionally adding one or more co-monomers selected from dienes, branched mono-olefins, and vinyl aromatics, to provide a monomer feed, and polymerizing the monomer feed by combining it with a Friedel-Crafts initiator in a vessel. The farnesene-based polymer or copolymer tackifier may be combined with one or more elastomers and one or more other tackifiers to form an adhesive composition.

An adhesive composition made from an elastomer and a tackifying resin. The tackifying resin includes a farnesene polymer or copolymer having the following properties: i) less than 10 weight percent of volatile organic compounds; ii) Mn between 300 Da and 1000 Da; iii) Mw between 400 Da and 3000 Da; iv) Mw/Mn between 1.00 and 3.00; v) Tg between 50 C. and 20 C.; and vi) viscosity between 400,000 cP and 1,000,000 cP at 25 C. A method of making the farnesene-based polymer or copolymer includes combining a farnesene monomer and a solvent and optionally adding one or more co-monomers selected from dienes, branched mono-olefins, and vinyl aromatics, to provide a monomer feed, and polymerizing the monomer feed by combining it with a Friedel-Crafts initiator in a vessel. The farnesene-based polymer or copolymer tackifier may be combined with one or more elastomers and one or more other tackifiers to form an adhesive composition.

A copolymer of ethylene and of myrcene, in which the ethylene units represent between 50 mol % and 95 mol % of the ethylene units and of the myrcene units, and the myrcene units of 1,2 and 3,4 configuration represent more than 50 mol % of the myrcene units, is provided. Such a copolymer exhibits an improved compromise between the degree of crystallinity and the stiffness. It therefore makes it possible to widen the field of application of ethylene-rich diene copolymers in rubber compositions, and also to increase the production capacity of a unit for the synthesis of ethylene-rich diene polymers.

The present invention is directed to a functionalized elastomer, wherein the functionalized elastomer is a copolymer of a first monomer and a second monomer, the first monomer selected from the group consisting of conjugated diene monomers and vinyl aromatic monomers, and the second monomer of formula 1

##STR00001##

wherein R.sub.1=C1-C8 alkyl, aryl, substituted aryl, or SiR.sub.3 where R.sub.3 are independently C1-C8 alkyl; R.sub.2=C1-C8 alkyl, aryl, or substituted aryl, or SiR.sub.3; and n=0-3.

An acetylacetone derivative is useful for capturing a metal element by complexation. A convenient and very versatile synthesis method can be used to synthesize the derivative. The derivative can have the following formula: ##STR00001##

A polymer composition comprising a star-branched copolymer having a plurality of arms is disclosed. Each polymer arm has a molecular weight Mp of from 1 kg/mol to 50 kg/mol and comprises polymerized units (i) derived from a first vinyl aromatic monomer comprising a radical-reactive group, wherein from greater than 10 mol % to 100 mol % of the units (i) are unhydrogenated; and optionally, polymerized units (ii) comprising hydrogenated and unhydrogenated forms of polymerized units derived from a high Tg monomer, and hydrogenated form of polymerized units (i) or hydrogenated form of polymerized styrene units; and optionally, polymerized units (iii) comprising (a) hydrogenated form of polymerized units derived from one or more acyclic conjugated dienes, and (b) polymerized units derived from one or more of a second vinyl aromatic monomer; wherein less than 10 wt. % of units (a) are unhydrogenated.