• 文献标题:   Colloidal stability of graphene oxide nanosheets in association with triblock copolymers: A neutron scattering analysis
  • 文献类型:   Article
  • 作  者:   PATIL R, MARATHE D, ROY SP, RAY D, ASWAL VK, JHA PK, BAHADUR P, TIWARI S
  • 作者关键词:   graphene oxide, colloidal stability, noncovalent adsorption, small angle neutron scattering, block copolymer, mass fractal
  • 出版物名称:   MATERIALS SCIENCE ENGINEERING CMATERIALS FOR BIOLOGICAL APPLICATIONS
  • ISSN:   0928-4931 EI 1873-0191
  • 通讯作者地址:   Uka Tarsadia Univ
  • 被引频次:   2
  • DOI:   10.1016/j.msec.2019.110559
  • 出版年:   2020

▎ 摘  要

This study investigates stabilization of graphene oxide (GO) nanosheets in polyethylene oxide-polypropylene oxide (PEO-PPO) block copolymers (P103, P123 and F127). Changes in micellization of copolymers upon GO addition were monitored using dynamic light (DLS) and small angle neutron scattering (SANS). Structural developments at sheet surface were studied with two possibilities; (1) adsorption of PPO block over hydrophobic basal plane allowing the engagement of hydrophilic PEO with aqueous bulk, and (ii) adsorption of micelles mediated via carboxylated groups. Insignificant changes in micellar parameters for P123 and P127 were indicative of their inferior interaction with GO. On the other hand, P103 micelles exhibited high affinity for sheets, noticeable as emergence of mass fractals and more than two-fold enhancement in micelle number density. The latter allowed coverage of entire surface with P103 micelles. Existence of mass fractals was verified by extracting the form and structure factors from the fitted SANS data. Spectroscopic and thermogravimetric analyses illustrated non-covalent adsorption of copolymer aggregates. It was interesting to note that the dispersion remained stable against protein and electrolyte addition. A comprehensive understanding on colloidal stability can be valuable for drug delivery applications of GO sheets.