Effect of polymer properties on poly(vinylidene fluoride) particles produced by rapid expansion of CO2 + polymer mixtures

The generation of nanoscale primary poly(vinylidene fluoride) (PVDF) particles by rapid expansion of supercritical solutions (RESS) is reported. The experimental results show that RESS enables the formation of PVDF particles with median particle diameters ranging from 56 to 226 nm and that the size of PVDF particles can be influenced by polymer properties. The particle size can be decreased either by increasing molar mass, in case of identical polymer end groups, or by increasing the degree of crystallinity, in case of similar molar mass and different end groups.

Influence of polymer molar mass and end group on PVDF particle sizes obtained from RESS experiments performed at TE = 323 K, p0 = pE = 20 MPa and T0 = 333 K.Figure optionsDownload as PowerPoint slide