An article comprising a polymeric foam, wherein the polymeric foam contains a continuous polymer matrix defining cells therein, the polymer matrix containing: (a) from 25 to 65 weight percent of one or more olefin block copolymer having a melt index of two grams per ten minutes or more, (b) from 65 to 25 weight percent of one or more chlorinated olefin polymer having a Mooney viscosity less than 60 (ML 1+4, 125° C.), and (c) from 5 to 30 weight parts of antimony trioxide relative to 100 weight parts of polymers in the polymeric foam, with weight percent values relative to total polymer weight in the polymeric foam; a process for preparing the article.