| 摘要 |
<p>Disclosed is a container stopper comprising a foamed article having a foaming ratio of 1.1 to 2.5, said foamed article being obtained by foaming a mixture of a thermoplastic elastomer composition comprising 100 parts by mass of a powdery hydrogenated block copolymer (a), which is obtained by hydrogenating a block copolymer comprising a polymer block (A) containing a structural unit originating in an aromatic vinyl compound and another polymer block (B) containing a structural unit originating in isoprene or an isoprene/butadiene mixture and containing a 3,4-bond unit and a 1,2-bond unit in a total amount of 45% or more, and has a peak top molecular weight (Mp), determined on polystyrene equivalent basis by gel permeation chromatography, of 250,000-500,000 and a bulk density of 0.10-0.40 g/ml; 5-150 parts by mass of a softening agent (b); and 5-150 parts by mass of a polyolefin resin (c), with 0.1-3 mass%, relative to the total mass of the thermoplastic elastomer composition, of a foaming agent (d).</p> |
