No abstract

Direct fullerenation of polycarbonate (PC), a commercially important optical polymer, is achieved by simply irradiating a solution of PC and C60 at room temperature using a conventional UV lamp or by warming up a C60/PC solution to a moderate temperature (60 °C) in the presence of AIBN, a typical radical initiator. The extent of fullerenation is controllable by varying the C60 feed ratio, and a fullerenated PC with a C60 content as high as 6.3 wt % (or more than two C60 molecules per PC chain) is readily prepared in almost quantitative yield (99.7%). Molecular weights of the fullerenated PCs are higher than that of the parent polymer, suggesting that the fullerenation is realized via multiaddition to C60. The multiaddition, however, has not led to heavy cross-linking, and the fullerenated PCs are soluble in common organic solvents such as THF and chloroform. The fullerenation involves a radical mechanism, and its general applicability to other polymer systems is demonstrated by the ready attachment of C60 to poly(vinyl chloride), another commercially important polymer, by employing the AIBN-initiated fullerenation reaction.

Fullerenation of polycarbonate (PC) is achieved by direct reaction of C60 with PC using AlCl3 as catalyst. Stirring a 1,1,2,2-tetrachloroethane solution of C60 and PC in the presence of AlCl3 under nitrogen at 140 °C for 24 h attached C60 to the PC chains, yielding fullerenated PCs (C60-PCs) with a C60 content up to 2.16 wt %. The C60-PCs are soluble in tetrahydrofuran (THF) and chloroform, and IR, UV, and NMR analyses suggest that they possess the molecular structure HxC60(PC)x with x < 1 on the average. The C60-PCs limit strong 532-nm optical pulses more effectively than the parent C60. Light transmission spectra of the C60-PC solutions red-shift with increasing concentration, with their cutoff wavelengths predictably tunable by simply changing their concentrations.