Patent ID: 7658989

Claim:
A polymeric material that has a plurality of cells formed therein, said polymeric material comprising: a foamed layer comprising a plurality of uniform cells having an average diameter of 10 nm to 10 μm in a closed cell network, wherein said foamed layer is present in a volume ranging from about 80 to about 99 percent based on the volume of the polymeric material; a transition layer positioned adjacent said foamed layer, wherein said transition layer is present in a volume ranging from about 0 to about 10 percent based on the volume of the polymeric material; and at least one unfoamed outer layer positioned adjacent to said transition layer, wherein said outer layer is present in a volume ranging from about 0.01 to about 10 percent based on the volume of the polymeric material wherein the material has a thickness ranging from 0.1 μm to 200 μm.