FOAM MATERIALS FOR INSULATION, DERIVED FROM HIGH INTERNAL PHASE EMULSIONS

摘要

The present invention relates to compressable polymeric foam materials usefu l as insulation. These polymeric foams are prepared by polymerization of certa in water-in-oil emulsions having a relatively high ratio of water phase to oil phase, commonly known as "HIPEs". The polymeric foam materials comprise a generally hydrophobic, flexible or semi-flexible, non-ionic polymeric foam structure of interconnected open-cells. The foam structures have: (a) a specific surface area per foam volume of at least about 0.01 m2/cc; (b) an expanded density of less than about 0.05 g/cc; and (c) a ratio of expanded t o compressed thickness of at least about 3:1; wherein when the foam is compressed to 33 % of its original expanded thickness and is thereafter maintained without artificial restraint on its surface, said foam will reexpand by no more than 50 % after 21 days at ambient temperature (22 ~C). In a preferred embodiment, the foams of the present invention, when heated to their Tg or higher, will reexpand to 90 % of their original thickness within about 1 day or less. The invention also relates to a process for making the compressible polymeric foam material comprising polymerizing a water-in-oil emulsion having a volume to weight ratio of water phase to oil phase in the range of from about 20:1 to about 250:1.