| 摘要 |
<p>A foam of a polyolefin/polystyrene resin mixture obtained by mixing a polyolefin resin and a polystyrene resin in the presence of a hydrogenated styrene/butadiene block copolymer, and subjecting the resultant mixed resinous composition to extrusion foaming, wherein: 1) said hydrogenated styrene/butadiene block copolymer comprises, as components before hydrogenation, 10 to 38 % by weight of styrene and butadiene with a content of 1,2-bond type butadiene of 20 to 50 % by weight based on butadiene; and 2) said foam comprises a thin surface skin portion showing a value of 0.65 or more of the surface structural index S represented by the following formula: S = t/T >/= 0.65 wherein t and T each represent a total light-transmission evaluated according to the method of ASTM D1003 with respect to a surface skin layer and an inner layer of the foam, is found to have the cushioning properties (or the foam properties) that enables elastic cushioning of a large load.</p> |
