A block copolymer is disclosed. The block copolymer has a structure of formula (V) below:

[D].sub.x-[E].sub.y-[F].sub.z  (V) wherein D, E, and F are each independently a compound of formula (VI) below, and D, E, and F are different from each other; and x, y, and z are each independently an integer from 1 to 40;

##STR00001## wherein A.sub.2 is O or S; R.sub.7 is H or a C.sub.1-6 alkyl; and R.sub.8 is a C.sub.1-12 alkyl, (CH.sub.2).sub.qN(R.sub.11).sub.2, CH.sub.2(CH.sub.2OCH.sub.2).sub.rCH.sub.2N(R.sub.12).sub.2, or CH.sub.2(CH.sub.2OCH.sub.2).sub.sCH.sub.2OR.sub.13, wherein R.sub.11, R.sub.12, and R.sub.13 are each independently a C.sub.1-6 alkyl; and q, r, and s are each independently an integer from 1 to 10.

A vulcanizable composition comprising rubber component, a filler, and a curing agent, where the rubber component includes a block copolymer of polybutadiene and polyisoprene, and where the block copolymer has a cis content of at least 90%.

A vulcanizable composition comprising rubber component, a filler, and a curing agent, where the rubber component includes a block copolymer of polybutadiene and polyisoprene, and where the block copolymer has a cis content of at least 90%.

The present invention relates to a chain transfer agent including an organozinc compound, a preparation method thereof, and a method for preparing a block copolymer using the same. A chain transfer agent prepared by a preparation method including preparing a Grignard reagent containing styrene residues, and reacting the prepared Grignard reagent with alkyl zinc alkoxide, which is a zinc compound, has not catalyst poison and by-products, and contains 96 wt % or more of a target compound. A block copolymer polymerized using the chain transfer agent and a resin composition including the block copolymer have excellent mechanical properties.

A block copolymer and a method for preparing the same are disclosed. The method comprises the following steps: (A) mixing a compound of formula (I), a catalyst of formula (II), and a first solvent to obtain a first mixture; (B) adding a first monomer into the first mixture for reaction to obtain a second mixture; and (C) adding a second monomer into the second mixture for reaction to obtain a third mixture; wherein the compound of formula (I) and the catalyst of formula (II) are as defined in the specification.

Provide is a polymer that can provide excellent toughness and weather resistance to a rubber composition and a rubber product such as a tire. The multicomponent copolymer contains a conjugated diene unit, a non-conjugated olefin unit and an aromatic vinyl unit, where a proportion of conjugated diene units bonded to a unit other than a conjugated diene unit out of the total conjugated diene units is 50% or more.

The present invention provides polymers and methods of preparing the same. In certain embodiments, the polymers comprise acrylate repeating units that have been derivatized (e.g., reduced and/or substituted) to form new polymeric structures. In certain embodiments, the polymers described herein self-assemble to form well-defined nanostructures. In some instances, the nanostructures exhibit relatively small d-spacing (e.g., a d-spacing value of 10 nm or less). Due to their properties, the polymers described herein are useful in a variety of applications including functional materials and biomedical applications.

The present invention provides polymers and methods of preparing the same. In certain embodiments, the polymers comprise acrylate repeating units that have been derivatized (e.g., reduced and/or substituted) to form new polymeric structures. In certain embodiments, the polymers described herein self-assemble to form well-defined nanostructures. In some instances, the nanostructures exhibit relatively small d-spacing (e.g., a d-spacing value of 10 nm or less). Due to their properties, the polymers described herein are useful in a variety of applications including functional materials and biomedical applications.

Metallic complexes having indenyl ligands can be used as an ingredient of a catalyst system. The catalyst system can be used in polymerizations of ethylenically unsaturated hydrocarbon monomers that include both olefins and polyenes. Embodiments of the catalyst system can provide interpolymers that include polyene mer and from 40 to 75 mole percent ethylene mer, with a plurality of the ethylene mer being randomly distributed. The catalyst system also can be used in solution polymerizations conducted in C.sub.5-C.sub.12 alkanes, yielding interpolymers that include at least 10 mole percent ethylene mer.

Metallic complexes having indenyl ligands can be used as an ingredient of a catalyst system. The catalyst system can be used in polymerizations of ethylenically unsaturated hydrocarbon monomers that include both olefins and polyenes. Embodiments of the catalyst system can provide interpolymers that include polyene mer and from 40 to 75 mole percent ethylene mer, with a plurality of the ethylene mer being randomly distributed. The catalyst system also can be used in solution polymerizations conducted in C.sub.5-C.sub.12 alkanes, yielding interpolymers that include at least 10 mole percent ethylene mer.