TY - JOUR
T1 - Unveiling the Mechanism of Polymer Grafting on Graphene for Functional Composites
T2 - The Behavior of Radicals
AU - Hori, Yuki
AU - Kubo, Koichiro
AU - Nishina, Yuta
N1 - Funding Information:
In summary, we confirmed the radicals generated by the reduction of GO enabled grafting various polymers on GO. ESR measurement of GO and vinyl monomer by the spin trap method supports that polymer addition to GO proceeds by a radical mechanism. As for the active radical species for the polymerization, we discovered unstable σ radicals generated by the removal of oxygen functional groups worked as active species, but stable π radicals are silent for the polymerization. Based on this principle, functional polymers could be immobilized on GO using GO as an initiator and support material. The composite of GO and PAN was converted to an electron conductive sheet by heat treatment. The GO composite with PVP was applied for a base catalyst, and that with PSS was applied for an acid catalyst. The control of the types and amount of polymers by tuning the functional groups on GO will extend the functionality of polymer‐GO composites. This research was supported by JSPS KAKENHI (19H02718).
Publisher Copyright:
© 2020 Wiley-VCH GmbH
PY - 2021/4
Y1 - 2021/4
N2 - Polymer–graphene composites have attracted significant attention; however, their formation mechanisms are a focus of debate. This work tries to clarify how grafting occurs on graphene by electron spin resonance techniques. As a result, two pathways are found. One passes through the radicals formed by cleaving C-O bonds on graphene are transferred to monomers, then grafting and polymerization proceed. Another mechanism passes through the oxy-radicals, which react with monomers in solution and finally react with carbon radicals on graphene. Based on the mechanism, various types of polymer–graphene composites are prepared, and applied to electrical conductive sheets, basic catalysts, and acidic catalysts.
AB - Polymer–graphene composites have attracted significant attention; however, their formation mechanisms are a focus of debate. This work tries to clarify how grafting occurs on graphene by electron spin resonance techniques. As a result, two pathways are found. One passes through the radicals formed by cleaving C-O bonds on graphene are transferred to monomers, then grafting and polymerization proceed. Another mechanism passes through the oxy-radicals, which react with monomers in solution and finally react with carbon radicals on graphene. Based on the mechanism, various types of polymer–graphene composites are prepared, and applied to electrical conductive sheets, basic catalysts, and acidic catalysts.
KW - electron spin resonance
KW - functional polymers
KW - grafting
KW - graphene oxide
KW - radical
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U2 - 10.1002/marc.202000577
DO - 10.1002/marc.202000577
M3 - Article
C2 - 33251648
AN - SCOPUS:85096832776
VL - 42
JO - Macromolecular Rapid Communications
JF - Macromolecular Rapid Communications
SN - 1022-1336
IS - 8
M1 - 2000577
ER -