EXPANDABLE PARTICULATE POLYMER COMPOSITION

摘要

An expandable particulate interpenetrating network polymer (IPN) composition includes a pentafluorobutane expansion agent and optionally a minor amount of heptafluoropropane The expandable particulate IPN includes (?) 10-80% polyolefin polymer, and (n) 20- 90% vinyl aromatic polymer, based on total weight of the particulate IPN The expansion agent resides (or is impregnated) within the particulate interpenetrating network polymer The pentafluorobutane may be 1,1,1,3,3-pentafluorobutane, and the heptafluoropropane may be 1,1,1,2,3,3,3-heptafluoropropane The expansion agent may consist of 1,1,1,3,3-pentafluorobutane The expandable particulate IPN compositions of the present invention have improved expansion agent retention values, relative to comparative expandable particulate IPN compositions (e g, containing isopentane as an expansion agent).