Abstract
The aggregate development in C60/N-methyl-2-pyrrolidone (C60/NMP) solution with time is studied by the extraction (hexane) and mass spectroscopy. It is shown that only molecular C60 in NMP is extracted in hexane, which makes it possible to follow a change in the concentration of non-aggregated fullerene in C60/NMP during the aggregate growth. It is concluded that almost all fullerene dissolved in NMP is in the aggregates after one month. The reorganization of the aggregates is detected when water is added to the
aggregated solution C60/NMP. Both methods prove that in this case individual fullerene molecules are
detached from the aggregates, which contradicts somewhat to complete insolubility of C60 in water.