V. Bernardo n, J.Martín-deLeón,M.A.Rodríguez-Pérez Cellular MaterialsLaboratory(CellMat),CondensedMatterPhysicsDepartment,UniversityofValladolid,CampusMigue Delibes,PaseodeBelénno. 7,47011 Valladolid, Spain
Nanocellular foams have been produced by means of a gas dissolution process using polyphenylsulfone
(PPSU) as matrix polymer. Cell sizes in the range 20–30 nm and cell nucleation densities higher than
1015 cm3 have been achieved for materials with relative densities in the range 0.65–0.75. The influence
of both saturation pressure and foaming temperature has been studied. On the one hand, it has been
proved that there is a large influence of the amount of gas (CO2) absorbed in the final cellular structure,
in fact it has been found a critical CO2 uptake between 9% and 9.5% at which the cell sizes evolve from the micro to the nanoscale. On the other hand, it has been found that there is a wide range of foaming
parameters(foaming time and foaming temperature) in which nanocellular foams can be produced.