| 摘要 |
PROBLEM TO BE SOLVED: To obtain a biodegradable foam having a high ratio of closed cells and appropriate rigidity. SOLUTION: The foam is obtained by the foam molding of a composition constituted of an olefinic resin (a polyethylene-based resin or the like) and a starch with the use of an organic physical blowing agent containing at least isobutane. The organic physical blowing agent is constituted of isobutane alone or may be a mixed blowing agent of isobutane and at least one kind selected from n-butane, n-pentane, and isopentane which may contain not less than 40 wt.% isobutane. The ratio (weight ratio) of the starch to the olefinic resin (starch/olefinic resin) is about 1/99 to 60/40. The above foam may have an expansion ratio of about 18-90 times and a density of about 0.01-0.05 g/cm<SP>3</SP>. Further, the foam may have a ratio of closed cells of not less than 80%. COPYRIGHT: (C)2007,JPO&INPIT
|
