Polar modifier systems based on a blend of DTHFP, ETE, TMEDA, DMTHFMA and/or functionally similar compounds with BDMAEE and SMT are used to make block copolymers having high levels of pendant vinyl double bond repeat units, which is through highly selective 1,2-bond butadiene addition, low vinylcyclopentane formation, unimodal narrow molecular weight distribution, and a low level of randomized co-monomer repeat units. The block copolymers have very high levels of 1,2-vinyl content and high 3,4-vinyl bond addition of the conjugated diene monomer and low vinylcyclopentane content. The polar modifier systems provide a fast polymerization rate, with a unimodal narrow molecular weight distribution. The polar modifier systems allow operation at a higher temperature than in prior art systems, which reduces cooling requirements.

Polar modifier systems based on a blend of DTHFP, ETE, TMEDA, DMTHFMA and/or functionally similar compounds with BDMAEE and SMT are used to make block copolymers having high levels of pendant vinyl double bond repeat units, which is through highly selective 1,2-bond butadiene addition, low vinylcyclopentane formation, unimodal narrow molecular weight distribution, and a low level of randomized co-monomer repeat units. The block copolymers have very high levels of 1,2-vinyl content and high 3,4-vinyl bond addition of the conjugated diene monomer and low vinylcyclopentane content. The polar modifier systems provide a fast polymerization rate, with a unimodal narrow molecular weight distribution. The polar modifier systems allow operation at a higher temperature than in prior art systems, which reduces cooling requirements.

A method for synthesizing a thermoplastic elastomer comprising at least one polydiene block and at least one other poly(-methylstyrene) block comprises: polymerizing at least one diene monomer in a starting reaction medium comprising an anionic polymerization initiator and an aprotic non-polar solvent; polymerizing -methylstyrene to the living polydiene chain obtained in the preceding step comprising: maintaining the reaction medium containing the living diene elastomer obtained previously and -methylstyrene at a positive temperature, below the ceiling temperature for the polymerization of -methylstyrene; cooling the reaction medium obtained at the end of step a., to a temperature below 0 C.; simultaneously, successively or prior to the cooling step, adding a purified aprotic polar solvent to the reaction medium with a volume ratio of the polar solvent to the non-polar solvent of less than 1; and propagating the polymerization of -methylstyrene to the living polydiene chain.

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.

Disclosed herein is a styrenic block copolymer [A1-B1-C1], consisting essentially of polymer blocks A1, B1 and C1. A1 is a poly(para-alkylstyrene) block having a molecular weight from 1,000 to 60,000 g/mol. B1 is a hydrogenated polyisoprene block or a hydrogenated polybutadiene block having a molecular weight from 1,000 to 100,000 g/mol. C1 is a polystyrene block having a molecular weight from 1,000 to 100,000 g/mol; or a polymer block consisting essentially of polymerized styrene units, and hydrogenated butadiene and/or isoprene units, and having a molecular weight from 1,000 to 100,000 g/mol. Prior to hydrogenation, the block B1 has a vinyl content of 5-75 mol %; and the block C1 forms 1-80 wt % of the overall weight of the block copolymer. The selectively sulfonated forms of the copolymers are useful as high dielectric materials.

Metallated aminosilane compounds for use as functional initiators in anionic polymerizations and processes for producing an aminosilane-functionalized polymer using the metallated aminosilane compounds to initiate anionic polymerization of at least one type of anionically polymerizable monomer. Preferred use of the metallated aminosilane compounds results in rubber compositions for use in tires comprising an aminosilane functionalized polymer.

A method of producing a structure containing a phase-separated structure, the method including: applying a brush composition to a substrate to form a brush layer; forming a layer containing a block copolymer on the brush layer; and phase-separating the layer containing the block copolymer, the brush composition including a resin component (A), the resin component (A) containing a polymeric compound (A1) in which a first polymer block and a second polymer block are bonded to each other through a linking group containing a substrate adhering group.

Polar modifier systems based on a blend of DTHFP, ETE, TMEDA, DMTHFMA and/or functionally similar compounds with BDMAEE and SMT are used to make block copolymers having high levels of pendant vinyl double bond repeat units, which is through highly selective 1,2-bond butadiene addition, low vinylcyclopentane formation, unimodal narrow molecular weight distribution, and a low level of randomized co-monomer repeat units. The block copolymers have very high levels of 1,2-vinyl content and high 3,4-vinyl bond addition of the conjugated diene monomer and low vinylcyclopentane content. The polar modifier systems provide a fast polymerization rate, with a unimodal narrow molecular weight distribution. The polar modifier systems allow operation at a higher temperature than in prior art systems, which reduces cooling requirements.

A method for synthesizing a thermoplastic elastomer comprising at least one polydiene block and at least one other poly(-methylstyrene) block comprises: polymerizing at least one diene monomer in a starting reaction medium comprising an anionic polymerization initiator and an aprotic non-polar solvent; polymerizing -methylstyrene to the living polydiene chain obtained in the preceding step comprising: maintaining the reaction medium containing the living diene elastomer obtained previously and -methylstyrene at a positive temperature, below the ceiling temperature for the polymerization of -methylstyrene; cooling the reaction medium obtained at the end of step a., to a temperature below 0 C.; simultaneously, successively or prior to the cooling step, adding a purified aprotic polar solvent to the reaction medium with a volume ratio of the polar solvent to the non-polar solvent of less than 1; and propagating the polymerization of -methylstyrene to the living polydiene chain.

A brush composition usable for phase-separation of a layer containing a block copolymer formed on a substrate, the brush composition including a resin component (A), the resin component (A) containing a polymeric compound (A1) in which a first polymer block and a second polymer block are bonded to each other through a linking group containing a substrate adhering group.