TY - JOUR
T1 - Fragmentation studies of poly(propelene imine) dendrimers in the gas-phase by using electrospray ionization mass spectrometry (ESI-MS)
AU - Weener, J.W.
AU - Dongen, van, J.L.J.
AU - Hummelen, J.C.
AU - Meijer, E.W.
PY - 1997
Y1 - 1997
N2 - The prepn. and ESR spectroscopy of a series of fully functionalized poly(propylenimine) dendrimers (DAB-dendr-(NH2)n; n = 2, 4, 8, 16, 32, 64) with 3-carboxy-PROXYL radical end groups is described. The pendant nitroxyl end groups exhibit a strong exchange interaction. As a consequence, the ESR spectrum directly reveals the no. of end groups from the splitting between the hyperfine transitions for the lower generations. For the higher generations an increasingly exchanged-narrowed ESR spectrum is obsd. The temp. and solvent dependency of the exchange interaction is used to assess the dynamic behavior of the dendritic branches. FT-IR spectroscopy shows that a hydrogen-bonded network between the amide functionalities is present, consistent with the obsd. solvent effect on the ESR spectra
AB - The prepn. and ESR spectroscopy of a series of fully functionalized poly(propylenimine) dendrimers (DAB-dendr-(NH2)n; n = 2, 4, 8, 16, 32, 64) with 3-carboxy-PROXYL radical end groups is described. The pendant nitroxyl end groups exhibit a strong exchange interaction. As a consequence, the ESR spectrum directly reveals the no. of end groups from the splitting between the hyperfine transitions for the lower generations. For the higher generations an increasingly exchanged-narrowed ESR spectrum is obsd. The temp. and solvent dependency of the exchange interaction is used to assess the dynamic behavior of the dendritic branches. FT-IR spectroscopy shows that a hydrogen-bonded network between the amide functionalities is present, consistent with the obsd. solvent effect on the ESR spectra
U2 - 10.1016/0025-5416(86)90362-9
DO - 10.1016/0025-5416(86)90362-9
M3 - Article
SN - 0743-0515
VL - 77
SP - 147
EP - 148
JO - Polymeric Materials: Science and Engineering
JF - Polymeric Materials: Science and Engineering
ER -