| 摘要 |
The present invention relates to a foam comprising a polypropylene, wherein said polypropylene is produced in the presence of a metallocene catalyst, and the foam and/or the polypropylene has (have) a) a branching index g' of less than 1.00 and b) a strain hardening index (SHI@1 s) of at least 0.30 measured by a deformation rate d&egr;/dt of 1.00 sat a temperature of 180°C, wherein the strain hardening index (SHI) is defined as the slope of the logarithm to the basis 10 of the tensile stress growth function (lg(&eegr;&egr;)) as function of the logarithm to the basis of the Hencky strain (lg(&egr;)), in the range of Hencky strains between 1 and 3. |
