Propylene polymer foams

摘要

The present invention relates to a foam, a process for preparing the foam and an article containing the foam. The foam contains a coupled propylene polymer and has a density in of from 9.6 to 801 kg/m3 and has either a foamability factor of more than 1.8 to less than 2.8 and an open cell content less than 20 percent, or a foamability factor of at least 2.8 and less than 15 and an open cell content of less than 50 percent. The process includes heating a coupled propylene polymer having a melt flow rate from 0.2 to 20 g/10 min and a melt strength of at least 39 cN to a molten state to produce a molten polymer material and mixing said molten polymer material with a blowing agent under conditions to produce a foamed material having a density in the range of from 9.6 to 801 kg/m3.