TY - JOUR
T1 - Ordered Nanostructures of Carbon Nanotube–Polymer Composites from Lyotropic Liquid Crystal Templating
AU - Kasprzak, Christopher R.
AU - Scherzinger, Evan T.
AU - Sarkar, Amrita
AU - Miao, Miranda
AU - Porcincula, Dominique H.
AU - Madriz, Alejandro M.
AU - Pennewell, Zachary M.
AU - Chau, Sophia S.
AU - Fernando, Raymond
AU - Stefik, Morgan
AU - Zhang, Shanju
N1 - Publisher Copyright:
© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2018/9
Y1 - 2018/9
N2 - A series of polymer nanocomposites containing single-walled carbon nanotubes (SWNTs) are prepared from polymerizable quaternary ammonium surfactants using photo-polymerization and investigated by means of polarized optical microscopy, small-angle X-ray scattering, and rheological measurements. The surfactant monomers with various alkyl chains of nonpolar tails form lyotropic liquid crystalline (LLC) mesophases in aqueous medium with hexagonal packing of cylindrical micelles. The physical adsorption of nonpolar tails of surfactants on the surface of SWNTs results in de-bundled nanotubes. The LLC phase diagram is investigated as functions of alkyl chain length, concentration, temperature, and SWNTs. As such, addition of SWNTs does not change the hexagonal mesophases but enhances the order–disorder transition temperatures and alters the rheological behaviors. After photo-polymerization, the microstructures of hexagonal packing are changed while addition of SWNTs does not disrupt the resulting microstructures. The polymerized composites are consistent with both lamellar and gyroid nanostructures and a possible model is proposed to interpret the observed phenomenon. Under the shear flow, the defect-free monodomain structures are obtained in the LLC phase and subsequently locked in the solid film after polymerization.
AB - A series of polymer nanocomposites containing single-walled carbon nanotubes (SWNTs) are prepared from polymerizable quaternary ammonium surfactants using photo-polymerization and investigated by means of polarized optical microscopy, small-angle X-ray scattering, and rheological measurements. The surfactant monomers with various alkyl chains of nonpolar tails form lyotropic liquid crystalline (LLC) mesophases in aqueous medium with hexagonal packing of cylindrical micelles. The physical adsorption of nonpolar tails of surfactants on the surface of SWNTs results in de-bundled nanotubes. The LLC phase diagram is investigated as functions of alkyl chain length, concentration, temperature, and SWNTs. As such, addition of SWNTs does not change the hexagonal mesophases but enhances the order–disorder transition temperatures and alters the rheological behaviors. After photo-polymerization, the microstructures of hexagonal packing are changed while addition of SWNTs does not disrupt the resulting microstructures. The polymerized composites are consistent with both lamellar and gyroid nanostructures and a possible model is proposed to interpret the observed phenomenon. Under the shear flow, the defect-free monodomain structures are obtained in the LLC phase and subsequently locked in the solid film after polymerization.
KW - carbon nanotubes
KW - liquid crystal templating
KW - photo-polymerization
KW - polymer nanocomposites
KW - polymerizable surfactants
UR - http://www.scopus.com/inward/record.url?scp=85052377787&partnerID=8YFLogxK
U2 - 10.1002/macp.201800197
DO - 10.1002/macp.201800197
M3 - Article
AN - SCOPUS:85052377787
SN - 1022-1352
VL - 219
JO - Macromolecular Chemistry and Physics
JF - Macromolecular Chemistry and Physics
IS - 17
M1 - 1800197
ER -