Provided is a thermoplastic elastomer composition which does not undergo viscosity increase during melt molding, gelation and molding failure, while having excellent heat resistance and durability. A thermoplastic elastomer composition for tires, which contains (A) an ethylene-vinyl alcohol copolymer or a modified ethylene-vinyl alcohol copolymer, (B) a thermoplastic resin or a thermoplastic elastomer, which has a melting point of 200° C. or higher, and (C) an acid-modified elastomer in an amount of 20% by volume or more based on the amount of all polymer components. This thermoplastic elastomer composition for tires is characterized in that if this thermoplastic elastomer composition for tires is extruded at a piston speed of 5 min/min at a temperature that is higher than the melting point of the thermoplastic resin or thermoplastic elastomer (B) by 20° C. in a viscosity measurement by means of a capillary rheometer, the viscosity η.sub.2 in 800 seconds after the start of the extrusion is less than 120% of the viscosity η.sub.1 in 200 seconds after the start of the extrusion.

A thermoplastic elastomer composition possessing a good combination of elastic recovery, tear strength at 25° C., stress relaxation and reduced (improved) anisotropy, which is based on a hydrogenated block copolymer (A), a thermoplastic resin (B), a rubber softener (C) and a polyolefin elastomer (D), of specified types and proportions, and which is suitable for use in a variety of film and sheet applications.

Provided is a thermoplastic elastomer composition for a weather strip material which is used for obtaining a molded product which has excellent adhesiveness to both a thermoplastic elastomer adherend and a crystalline ethylene resin adherend and also has excellent heat resistance at a fused portion. The thermoplastic elastomer composition for a weather strip material according to the disclosure contains: an ethylene-α-olefin copolymer rubber (A); an α-olefin crystalline thermoplastic resin (B) having a melting point of 140° C. or higher; an olefin block copolymer (C) obtained by hydrogenating a block copolymer which has a conjugated diene polymer block with a 1,2-vinyl bond content of 25 mol % or less at both ends and also has a conjugated diene polymer block with a 1,2-vinyl bond content of more than 25 mol % in the middle; and a crystalline ethylene resin (D).

An eight-arm star-shaped thermoplastic elastomer copolymer and a preparation method therefor; a polystyrene-polyisoprene lithium compound and a polystyrene/diphenylethylene-polyisoprene lithium compound are synthesized by using active anionic polymerization, and the compounds are used for a coupling reaction with octenyl polyhedral oligomeric silasesquioxane to obtain the copolymer. The method has the characteristics of convenient operation, high reaction efficiency, mild reaction conditions, and few side reactions. The structure and molecular weight of the prepared eight-arm star-shaped polymer are controllable, and the molecular weight distribution is narrow. A polymer segment obtained by the copolymerization of diphenylethylene (DPE) and styrene (St) is used as a hard segment, which enables the eight-arm star-shaped thermoplastic elastomer copolymer to have more outstanding mechanical properties. At the same time, a polymer segment composed of DPE and St units has a higher glass transition temperature than polystyrene, which increases the upper limit usage temperature of the eight-arm star-shaped copolymer.

The present disclosure provides a thermoplastic resin composition having high rigidity and a low coefficient of linear thermal expansion and a molded article including the same. The thermoplastic resin composition includes a first propylene-ethylene copolymer, a second propylene-ethylene copolymer, a thermoplastic elastomer, an inorganic filler, and a sodium-phosphate-based nucleating agent as appropriate, and thus a molded article produced therefrom can exhibit improved mechanical rigidity, impact resistance, and dimensional stability. Even when formed to a low thickness for weight reduction, the molded article can be imparted with excellent processability, high tensile strength, a high flexural modulus, and high impact strength.

A thermoplastic elastomer composition and method of making the thermoplastic elastomer are disclosed. The thermoplastic elastomer may comprise a polymer blend. The polymer bland may comprise a non-crosslinked elastomer, oil, polyethylene, and anti-oxidant. The oil may be from about 15 wt. % to about 50 wt. % oil. The polyethylene may be from about 3 wt. % to about 30 wt. %. The anti-oxidant may be from about 0 to about 0.5 wt. %.

The present disclosure provides a thermoplastic resin composition having high rigidity and a low coefficient of linear thermal expansion and a molded article including the same. Specifically, the thermoplastic resin composition includes a polypropylene-based resin having an isotactic pentad fraction of 96% or more as measured by .sup.13C-NMR, a thermoplastic elastomer, an inorganic filler having an average particle diameter of 0.1 μm to 5 μm, and a compatibilizer, and has a flexural modulus of 2,500 MPa or more and a coefficient of linear thermal expansion of 60 μm/m.Math.° C. or less.

The present disclosure provides a thermoplastic resin composition having high rigidity and a low coefficient of linear thermal expansion and a molded article including the same. Specifically, the thermoplastic resin composition includes a polypropylene composite resin including high-crystalline polypropylene and the like, an elastomer, and an inorganic filler.

The present disclosure provides a thermoplastic resin composition having high rigidity and a low coefficient of linear thermal expansion and a molded article including the same. Specifically, the thermoplastic resin composition includes a first polypropylene resin having crystallinity of 50% to 80%, a second polypropylene resin having a coefficient of linear thermal expansion of 70 μm/m° C. to 90 μm/m° C., an elastomer, and an inorganic filler.

Disclosed is a polyolefin thermal insulation foam and use thereof, and to a method for preparing a physically foamed polyolefin thermal insulation foam, which can be recycled well and which has excellent flexibility characteristics.