Provided is a hydrogenated block copolymer composition comprising a hydrogenated block copolymer A represented by General Formula (A) and a hydrogenated block copolymer B represented by General Formula (B), wherein the weight ratio (A/B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B is 10/90 to 80/20, and the hydrogenation ratio of olefins in the polymer components constituting the hydrogenated block copolymer composition is 10 to 100%:

Ar1.sup.a-HD.sup.a-Ar2.sup.a  (A)

Ar1.sup.b-HD.sup.b-A2.sup.b  (B)

wherein in General Formulae (A) and (B) above, Ar1.sup.a, Ar1.sup.b, Ar2.sup.a, and Ar2.sup.b are each an aromatic vinyl polymer block, HD.sup.a and HD.sup.b are each a hydrogenated polymer block of a conjugated diene polymer, and the ratio (Mw(Ar2.sup.a)/Mw(Ar1.sup.a)) of the weight average molecular weight of Ar2.sup.a (Mw(Ar2.sup.a)) to the weight average molecular weight of Ar1.sup.a (Mw(Ar1.sup.a)) is 2.6 to 66.

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.

Provided are a water-absorbent resin easily separable from a recyclable resource in recovering the recyclable resource, and an absorbent article containing an absorbent material containing the water-absorbent resin. The water-absorbent resin according to the present invention has such a structure that a polymer formed from a water-soluble ethylenically unsaturated monomer is crosslinked by using a post-crosslinking agent. The water-absorbent resin has (1) a water-retention capacity for physiological saline of 35 g/g or more, (2) a water-absorption capacity for physiological saline under a load of 4.14 kPa of 10 mL/g or more, (3) an initial gel viscosity of 3000 mPa.Math.s or more, and (4) a gel decomposition index of 0.60 or less: gel decomposition index=B/A wherein A represents an initial gel viscosity (mPa.Math.s), and B represents a gel viscosity after one day (mPa.Math.s).

The subject matter described herein relates to methods for polymer xanthylation and the xanthylated polymers produced by such methods. Subsequent replacement of the xanthylate moiety allows facile entry into functionalized polymers.

The conjugated diene-based polymer of the invention comprises an aromatic vinyl unit based on an aromatic vinyl compound and a conjugated diene unit based on a conjugated diene compound, is modified with a compound containing a heteroatom, and has an SP value of 16.80 MPa.sup.1/2 to 17.10 MPa.sup.12.

A modified conjugated diene-based polymer having a weight average molecular weight of 20×10.sup.4 or more and 300×10.sup.4 or less, and having a molecular weight distribution Mw/Mn of 1.6 or more and 4.0 or less, wherein a modification ratio with respect to a total amount of the conjugated diene-based polymer is 50% by mass or more, a modification ratio of a component having a molecular weight which is ½ of a molecular weight at a peak top, or a peak top of the minimum molecular weight when a plurality of the peak tops of molecular weights is present, in a gel permeation chromatography curve is ½ or more of the modification ratio with respect to the total amount of the conjugated diene-based polymer, and a content of nitrogen contained in the modified conjugated diene-based polymer is 3 mass ppm or more and 70 mass ppm or less.

A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units of 60 mol % or more and less than 95 mol %, and having an average particle diameter from 50 to 2000 μm. The production method is capable of controlling the particle shape and does not cause the problem of the residual sulfur content, and is further convenient and economically advantageous.

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Disclosed is a modified polyisobutylene polymer for rubber compounding. The modified polyisobutylene polymer is prepared by reacting reactants including a polyisobutylene in which the main chain is isobutylene, an unsaturated dicarboxylic anhydride, and an amino group-containing silane compound. The modified polyisobutylene polymer includes a diamide structure. When the modified polyisobutylene polymer is used as an additive for rubber compounding, the processability of the rubber is increased, the dispersibility of fillers is significantly improved, and the effect of obtaining excellent grip performance and improved rolling resistance can be achieved.

The present invention relates to a process for producing PEG acrylate-HNBR copolymer which exhibits excellent processability by latex hydrogenation of PEG acrylate-NBR latex to afford PEG acrylate-HNBR latex and subsequent coagulation.

Disclosed herein are modified diene-containing (co)polymers, in particular, modified styrene-butadiene copolymer, which can be used as flame retardants for expandable polystyrene polymer compositions. In particular, disclosed is a modified diene-containing (co)polymer, a method for preparing it, and use as a flame retardant for expandable polystyrene. The modified diene-containing (co)polymer claimed in the invention is characterized by high thermostability, namely, a 5% weight loss temperature of at least 180° C., a molecular weight of at least 1500 g/mol and a halogen content of at least 35 wt. %; the content of tertiary and/or allyl halogenides is in the range from 0 to less than 1.5 wt. %, and also does not affect the polymerization process and the formation of polystyrene granules either, and allows to obtain polystyrene granules with a yellowness index of 2 to 6 units, comparable to the yellowness index of polystyrene granules containing HBCD (from 0 to 3 units).