Gas foaming to generate hollow polymeric micro- and nano-particles
Orsi Silvia (1), Di Maio Ernesto (2)*, Netti Paolo Antonio (3), Iannace Salvatore (4)
(1) Center for Advanced Biomaterials for Health Care@CRIB, Istituto Italiano di Tecnologia - - Italy, (2) DICMAPI, University of Naples Federico II - - - Italy, (3) DICMAPI, University of Naples Federico II and Center for Advanced Biomaterials for Health Care@CRIB, - - Italy, (4) Institute for Composite and Biomedical Materials of the National Research Council - - Italy
The gas foaming technology has been successfully utilized, for the first time, to produce hollow polymeric particles of micrometric or nanometric characteristic dimension. Carbon dioxide and nitrogen up to pressures of 14 MPa were used as blowing agents for polystyrene spheres with diameters ranging from 200 nm to 50 um. Focused Ion Beam-Scanning Electron Microscopy, Transmission Electron Microscopy and Confocal Microscopy were used to assess the occurrence of bubble within the particles, their shape and dimension and the closed/open character.