Synthesis and Properties of [60] Fullerene-Polymethyl Methacrylate Conjugates in Supercritical Carbon Dioxide

[60] Fullerene (C60) almost completely inhibits the polymerization of most vinyl monomers, but our investigation shows that the concentration of radical initiators and reaction conditions greatly enhances conjugation formation. In the present investigation, a series of [60] fullerene-polymethyl methacrylate conjugates was synthesized through 2,2-azobisisobutyronitrile (AIBN)-initiated in situ polymerization of methyl methacrylate (MMA) under different reaction conditions in supercritical carbon dioxide (scCO2). This has afforded corresponding [60] fullerene-PMMA conjugates with [60] fullerene content (%) and rheoviscosity range of 0.79-4.69% and 1.069-1.345Mpas, respectively. The process of in situ polymerization was monitored at different concentrations (mol/dL) of AIBN (304.50-761.25x10-3) and MMA (9.41-23.53x10-3), and temperatures (60 degrees-90 degrees C), pressures (1400-2000psi), and time (2-8h). The progress of in situ polymerization was monitored rheoviscometrically in tetrahydrofuran at 25 +/- 1 degrees C. Selected [60] fullerene-PMMA conjugates were characterized through UV-vis, GPC, FT-IR, 1HMMR, 13CNMR spectra, and thermal characterization by TG.