| 摘要 |
<p>Disclosed are films made of expanded polypropylene, which have a uniform specific gravity d of from about 4.25 x 10-6 to about 6.50 x 10Newton/mm3, a crystallization temperature of from about 115.degree.C to about 135.degree.C and an elastic modulus Me expressed in Newton/mm3 such that the ratio Me:d is from about 1.6 x 108 to about 2.0 x 108 mm.</p> |
