Abstract: A thermoplastic polymer composition has good flexibility, lightweight properties, moldability, and heat resistance, and in particular, is excellent in wear resistance. The thermoplastic polymer composition includes: at least one block copolymer (a) selected from among an ?-methylstyrene based block copolymer having a number average molecular weight of 30,000 to 500,000 and a hydrogenated product thereof, the ?-methylstyrene based block copolymer including a polymer block A mainly composed of an ?-methylstyrene unit and a polymer block B mainly composed of a conjugated diene unit; a propylene-based polymer (b); and an ethylene-based polymer (c) having a density of 0.94 g/cm3 or less, in a ratio satisfying the following inequalities (1) and (2): 0.1?W(a)/[W(a)+W(b)+W(c)]?0.8??(1) 1?W(b)/W(c)??(2) wherein W(a), W(b), and W(c) represent the masses of the block copolymer (a), the propylene-based polymer (b), and the ethylene-based polymer (c), respectively.

Abstract: A block copolymer or hydrogenated product thereof having a polymer block A and a polymer block B, wherein: the polymer block A mainly comprises an aromatic vinyl compound unit and the aromatic vinyl compound unit contains a styrene unit in which an alkyl group having at least one functional group selected from a carboxyl group and a group derived therefrom is bound to a benzene ring; and the polymer block B mainly comprises a conjugated diene unit.

Abstract: The invention provides a curable resin composition having an addition polymerization-based block copolymer (I) and an ethylenic unsaturated compound (II). Also provided is a flexographic plate material using the curable resin composition as its constituent. The flexographic plate material containing the curable resin composition of the present invention, can be cured to form strong and extendable areas and can be used to make flexographic plates that can form a sharp image plate surface even for a fine image. The flexographic plate material of the present invention is particularly useful in printing on cardboards, recycled paper or other paper articles with rough surfaces.

Abstract: The present invention concerns a polymer composition comprising: a block copolymer (a) including a polymer block A, which is composed mainly of an ?-methylstyrene, and a hydrogenated or unhydrogenated polymer block B, which is composed of a conjugated diene or isobutylene and has a weight average molecular weight of 30,000 to 200,000; an acrylic resin (b); and a softener (c), wherein proportions (by mass) of the respective components in the polymer composition are such that each of the following relationships (1) and (2) holds: 0.05?Wb/Wa?2 and??(1) Wc/(Wa+Wb+Wc)?0.5??(2) wherein Wa, Wb, and Wc represent amounts (by mass) of the block copolymer (a), the acrylic resin (b) and the softener (c), respectively.

Abstract: The invention provides a curable resin composition having an addition polymerization-based block copolymer (I) and an ethylenic unsaturated compound (II), wherein: the addition polymerization-based block copolymer (I) is selected from block copolymers comprising at least one polymer block A and at least one polymer block B, and the hydrogenated products thereof; the polymer block A essentially comprises an aromatic vinyl compound unit containing at least 1% by mass of an alkylstyrene-derived structural unit (a) in which at least one alkyl group having 1 to 8 carbon atoms is bound to a benzene ring; the polymer block B essentially comprises a conjugated diene compound unit; and at least the moiety of polymer block A can undergo crosslinking upon exposure to an active energy ray. Also provided is a flexographic plate material using the curable resin composition as its constituent.

Abstract: The invention provides a polymer composition containing an addition polymerization-based block copolymer (a), an acrylic resin (b), and a softener (c), wherein the addition polymerization-based block copolymer (a) has a weight average molecular weight of 30000 to 200000 and is at least one selected from block copolymers comprising at least one polymer block A and at least one polymer block B, and hydrogenated products of the block copolymers; the polymer block A essentially comprises an aromatic vinyl compound unit containing at least 1% by mass of an alkylstyrene-derived structural unit (I) in which at least one alkyl group having 1 to 8 carbon atoms is bound to a benzene ring; the block copolymer B comprises a conjugated diene compound unit; and the components of the polymer composition are present in respective proportions (by mass) so that the following relationships (1) and (2) hold: 0.05?Wb/Wa?2??(1) Wc/(Wa+Wb+Wc)?0.

Abstract: A polyolefin-based resin composition comprising an addition polymerization-based block copolymer (I) and a polyolefin-based resin (II). The addition polymerization-based block copolymer (I) is selected from block copolymers comprising at least one polymer block A and at least one polymer block B, and the hydrogenated products thereof. The polymer block A comprises an aromatic vinyl compound unit comprising at least 1% by mass of an alkylstyrene-derived structural unit (a), in which at least one alkyl group having 1 to 8 carbon atoms is bound to a benzene ring. The polymer block B comprises a conjugated diene compound unit. A moiety of polymer block A can undergo crosslinking upon exposure to an active energy ray. After being molded into a desired shape, the composition is exposed to an active energy ray to carry out the crosslinking reaction. The composition exhibits flexibility, heat resistance, mechanical properties and solvent resistance in a well-balanced manner.

Abstract: The present invention concerns a polymer composition comprising: a block copolymer (a) including a polymer block A, which is composed mainly of an ?-methylstyrene, and a hydrogenated or unhydrogenated polymer block B, which is composed of a conjugated diene or isobutylene and has a weight average molecular weight of 30,000 to 200,000; an acrylic resin (b); and a softener (c), wherein proportions (by mass) of the respective components in the polymer composition are such that each of the following relationships (1) and (2) holds: 0.05?Wb/Wa?2??(1) and Wc/(Wa+Wb+Wc)?0.5??(2) wherein Wa, Wb, and Wc represent amounts (by mass) of the block copolymer (a), the acrylic resin (b) and the softener (c), respectively.

Abstract: (1) A methacrylic ester or an acrylic ester is anionically polymerized, using a polymerization initiator compound comprising an addition reaction product of a conjugated diene compound and an organic alkali metal compound, in the presence of a tertiary organoaluminum compound having in the molecule thereof a chemical structure represented by a formula: Al—O—Ar wherein Ar represents an aromatic ring; or (2) a methacrylic ester or an acrylic ester is anionically polymerized, using a polymerization initiator compound comprising an addition reaction product of an organic alkali metal compound and a compound having a 1,1-diaryl-1-alkene structure, by adding the ester in the form of a mixture with the above-mentioned specific tertiary organoaluminum compound to the polymerization system.

Abstract: (1) A methacrylic ester or an acrylic ester is anionically polymerized, using a polymerization initiator compound comprising an addition reaction product of a conjugated diene compound and an organic alkali metal compound, in the presence of a tertiary organoaluminum compound having in the molecule thereof a chemical structure represented by a formula: Al—O—Ar wherein Ar represents an aromatic ring; or

Abstract: (1) A methacrylic ester or an acrylic ester is anionically polymerized, using a polymerization initiator compound comprising an addition reaction product of a conjugated diene compound and an organic alkali metal compound, in the presence of a tertiary organoaluminum compound having in the molecule thereof a chemical structure represented by a formula: Al—O—Ar wherein Ar represents an aromatic ring; or (2) a methacrylic ester or an acrylic ester is anionically polymerized, using a polymerization initiator compound comprising an addition reaction product of an organic alkali metal compound and a compound having a 1,1-diaryl-1-alkene structure, by adding the ester in the form of a mixture with the above-mentioned specific tertiary organoaluminum compound to the polymerization system.

Abstract: A resin composition comprising (A) a polyolefin resin, (B) a vinyl alcohol copolymer and (C′) a block copolymer composed of a polymer block of an aromatic vinyl compound and an isobutylenic polymer block, the weight ratio of (A) to (B) ranging from 100/10 to 100/1000 and the weight ratio of (C′) to [(A)+(B)] ranging from 5/100 to 1000/100 is a flexible resin material having high gas barrier properties, good heat resistance and good moldability or formability so that it is useful as a material for various molded or formed articles.

Abstract: A resin composition comprising (A) a polyolefin resin, (B) a vinyl alcohol copolymer and (C′) a block copolymer composed of a polymer block of an aromatic vinyl compound and an isobutylenic polymer block, the weight ratio of (A) to (B) ranging from 100/10 to 100/1000 and the weight ratio of (C′) to [(A)+(B)] ranging from 5/100 to 1000/100 is a flexible resin material having high gas barrier properties, good heat resistance and good moldability or formability so that it is useful as a material for various molded or formed articles.

Abstract: Described are a thermoplastic polymer composition comprising (A) a block copolymer formed of a polymer block composed mainly of an aromatic vinyl compound and another polymer block composed mainly of isobutylene; and (B) a crosslinked rubber of at least one rubber selected from natural rubber, diene polymer rubber, olefin polymer rubber, acrylic rubber and fluorine rubber at a weight ratio of 90:10 to 10:90; and molded or formed products and hermetically sealing materials produced using the composition. The above thermoplastic polymer composition is excellent in moldability or formability, gas barrier properties, compression set resistance, hermetically sealing properties, sealing properties, flexibility, mechanical properties, oil resistance, safety, hygienic properties and the like.

Abstract: Herein disclosed are a block copolymer having an isobutylene-based polymer block and a vinylic aromatic hydrocarbon-based polymer block and containing a styrenic unit having a halogenated saturated aliphatic hydrocarbon group on the benzene ring at 0.01 to 2 mol % on a basis of the total structural units and being capable of markedly improving the performance of a synthetic resin when the block copolymer is blended with the synthetic resin; a process for producing the block copolymer; and a resin composition position containing the block copolymer.

Abstract: A closure or sealing element for containers, comprising a resin composition principally composed of a polyolefin resin (A) and a block copolymer (B) of a polymer block of an aromatic vinyl compound and an isobutylenic polymer block at a (A)/(B) weigh ratio within a range of 100/5 to 100/100, has so suitable pliability and excellent thermal resistance, good gas barrier properties and great oil resistance, that the closure or sealing element has good mountability onto (into) containers and excellent sealing properties of the containers in addition to good long-term shelf stability of the contents.

Abstract: Disclosed is a polymer composition which comprises as the main components an ethylene-vinyl alcohol base copolymer (A) and a block copolymer (B) which has a polymer block containing an aromatic vinyl monomer unit and a polymer block containing an isobutylene unit, and in which a phase composed of said component (A) and a phase composed of said component (B) are separated each other. This polymer composition has good flexibility or rubber elasticity and also good barrier properties to gases or the like and it can be molded or formed into a product having such properties without a vulcanization step so that it is useful as a material for packaging material for food or drink, container packing, medical container for infusion fluid or the like.

Abstract: A resin composition containing (A) an amorphous polyolefin resin and (B) a block copolymer comprising a polymer block of an aromatic vinyl compound and an isobutylene polymer block, at an (A)/(B) weight ratio within a range of 95/5 to 50/50, has remarkably improved impact resistance, with no deterioration of the excellent properties essential to the amorphous polyolefin resin (A), such as transparency.

Abstract: An isobutylene-based polymer as a polymer of cationically polymerizable monomers principally composed of isobutylene or a combination of isobutylene and a styrene-series monomer, generates a molded article with outstanding properties, the isobutylene-based polymer characteristically satisfying the following provisions;1. the isobutylene-based polymer has a substantially continuos molecular weight distribution on a gel-permeation chromatogram;2. the molecular weight at the highest peak on a gel-permeation chromatogram is within a range of 10,000 to 500,000; and3. the length (a) of the elution time in the lower molecular region of the mountain from the highest peak and the length (b) of the elution time in the higher molecular region of the mountain from the highest peak on a gel-permeation chromatogram, satisfy the provision represented by the formula (b)/(a).gtoreq.1.3.

Abstract: A process for producing a polymer of vinylic compounds comprising polymerizing at least one vinylic compound by using an initiator system comprising a compound containing, in the molecule, at least one group represented by the general formula:--C(--R.sup.1)(R.sup.2)--X (I)where each of R.sup.1 and R.sup.2 represents an alkyl, aryl or aralkyl group, and X represents an acyloxyl, alkoxyl or hydroxyl group or a halogen atom, and a Lewis acid, wherein(1) at least one of pyridine derivative (A) selected from the group consisting of a pyridine derivative (A-1) substituted at 2-position and 6-position with methyl group respectively and a pyridine derivative (A-2) substituted at 2-position with an alkyl group of 2 to 6 carbon atoms and not substituted at 6-position, and(2) an organic Lewis base (B) other than said pyridine derivative (A)are present together in the polymerizing reaction system.