Diamond Rings or Dumbbells: Controlling the Structure of Poly(ethylene glycol)–Fullerene  Adducts by Varying Linking Chain Length
journal contributionposted on 17.12.2015, 03:41 by Hin Chun Yau, Mustafa K. Bayazit, Joachim H. G. Steinke, Milo S. P. Shaffer
Fullerene  (C60) and poly(ethylene glycol) (PEG) adducts were prepared via 1,3-dipolar cycloaddition of bis-azido-terminated linear PEG (N3-PEG-N3) and C60. While long chain length PEGs (Mn = 1000 and 3350 Da) yielded the cyclic diamond ring structures (⊂C60PEG1000⊃ and ⊂C60PEG3350⊃), short-chained PEG (Mn = 200 Da) yielded a telechelic dumbbell structure (C60-PEG200-C60). Both dumbbell and diamond ring structures were characterized by MALDI-TOF-MS, 1H NMR, FTIR, UV–vis, and elemental analysis (EA). The results highlight the structural dependence of the PEG-C60 adducts on the chain length of the azido-terminated polymer, a factor previously neglected.