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.

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.

The cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding any of a class of morpholine compounds to a catalyst composition that includes a lanthanide metal atom.

The cis-1,4 mer content of conjugated diene mer in polymers can be increased by adding any of a class of morpholine compounds to a catalyst composition that includes a lanthanide metal atom.

Embodiments of the present disclosure directed towards polymerization catalysts having improved ethylene enchainment. As an example, the present disclosure provides a polymerization catalyst having improved ethylene enchainment, the polymerization catalyst comprising a zirconocene catalyst of Formula (I) where R.sub.1 is a C.sub.1 to C.sub.20 alkyl, aryl or aralkyl group, wherein R.sub.2 is an C.sub.1 to C.sub.20 alkyl, aryl or aralkyl group, and where R.sub.3 is a C.sub.1 to C.sub.20 alkyl or a hydrogen, and where each X is independently a halide, C.sub.1 to C.sub.20 alkyl, aralkyl group or hydrogen. ##STR00001##

A block copolymer composition is disclosed herein. In some embodiments, a block copolymer composition has a weight average molecular weight (M.sub.w) of 70,000 g/mol to 120,000 g/mol, a polydispersity index (PDI) of 1.0 to 2.0, a glass transition temperature (T.sub.g) of −55° C. to −30° C., and a melt index (MI), measured at 230° C. and a loading condition of 5 kg, of 0.2 g/10 minutes to 3.0 g/10 minutes. The block copolymer composition has excellent processability.

Sustained-release composite particles having improved dispersion stability and improved sustained-release properties, and exhibiting longer-term effects, a method for producing the sustained-release composite particles, a dry powder comprising the sustained-release composite particles, and wallpaper comprising the sustained-release composite particles. The sustained-release composite particles comprise core particles containing at least one type of polymer and at least one type of functional component, and micronized cellulose coating at least a part of the surface of the core particles, the core particles and the micronized cellulose being inseparable from each other.

Sustained-release composite particles having improved dispersion stability and improved sustained-release properties, and exhibiting longer-term effects, a method for producing the sustained-release composite particles, a dry powder comprising the sustained-release composite particles, and wallpaper comprising the sustained-release composite particles. The sustained-release composite particles comprise core particles containing at least one type of polymer and at least one type of functional component, and micronized cellulose coating at least a part of the surface of the core particles, the core particles and the micronized cellulose being inseparable from each other.

A method for producing a polydiene, the method comprising the step of: polymerizing conjugated diene monomer with a lanthanide-based catalyst system in the presence of a hydrocarbyloxysilane.

Provided is a method for producing a hydrogenated petroleum resin having good compatibility with a base polymer and a good hue under a hydrogen pressure of 4 MPaG or less.

A method for producing a hydrogenated petroleum resin, includes a hydrogenation step of hydrogenating a polymerization product of dicyclopentadiene and a vinyl aromatic compound in the presence of a catalyst, in which the hydrogenation step is performed under conditions (A) to (C) below: (A) an amount of the catalyst used: 0.125 to 0.4 parts by mass relative to 100 parts by mass of a resin in the polymerization product; (B) a reaction pressure: 4 MPaG or less; and (C) a reaction temperature: 240 C. or higher.