Synthesis of novel fullerene-functionalized polysulfones for optical limiting applications

High-performance materials in the optical field, with special reference to optical limiting applications, can be obtained by combining nonlinear optical (NLO) active molecules with high optical quality hosts. An interesting method is the synthesis of fullerene-polymer systems. In this paper novel fullerene-polysulfone samples were obtained by direct fullerenation between a commercial sample of polysulfone and fullerene, using electrophilic aromatic substitution reactions in the presence of AlCl3 as catalyst. The synthesis was successful; the molecular structures of the samples, confirmed by 1H NMR, IR, and UV analyses, indicate that fullerene is covalently bonded to the polysulfone chains. C60 is random distributed along the macromolecules, in amounts varying from 0.5 to 3.2 mol%. The C60-polysulfone materials show a very high thermal stability, a glass transition temperature depending on the C60 content, and interesting optical limiting properties.