A microdense sealing member is provided. The microdense sealing member includes a composition having a foamed silane-crosslinked polyolefin elastomer with a density less than 0.70 g/cm3. The microdense sealing member can exhibit a compression set of from about 5.0% to about 35.0% measured according to ASTM D 395 (22 hrs @ 70° C.). The foamed silane-crosslinked polyolefin elastomer can be produced from a blend including a first polyolefin having a density less than 0.86 g/cm3, a second polyolefin having a crystallinity less than 60° C., a silane crosslinker, a grafting initiator, a condensation catalyst, and a microencapsulated foaming agent.