Paper Number
CS40 

Session
Colloids and Suspensions

Title
Rheological behavior of nanostructured complex fluids with two-dimensional (2D) materials

Presentation Date and Time
October 16, 2024 (Wednesday) 3:45

Track / Room
Track 2 / Waterloo 4

Authors (Click on name to view author profile)

  1. Andrade, Ricardo E. (Universidade Presbiteriana Mackenzie, MackGraphe)
  2. Moraes, Nathalia M. (Universidade Presbiteriana Mackenzie, MackGraphe)
  3. Dias, Matheus (Mackenzie Presbyterian University)
  4. Maronezze, Camila (Mackenzie Presbyterian University, MackGraphe)
  5. Ribeiro, Helio (Universidade Presbiteriana Mackenzie, MackGraphe)
  6. Moraes, Lorena R. (Pontificia Universidade Catolica do Rio de Janeiro, Department of Mechanical Engineering)
  7. Soares, Yago (Pontifical Catholic University of Rio de Janeiro, Department of Mechanical Engineering)
  8. Naccache, Monica F. (Pontificia Universidade Catolica do Rio de Janeiro, Department of Mechanical Engineering)

Author and Affiliation Lines (in printed abstract book)
Ricardo E. Andrade1, Nathalia M. Moraes1, Matheus Dias1, Camila Maronezze1, Helio Ribeiro1, Lorena R. Moraes2, Yago Soares2 and Monica F. Naccache2
1MackGraphe, Universidade Presbiteriana Mackenzie, Sao Paulo, SP 01302907, Brazil; 2Department of Mechanical Engineering, Pontificia Universidade Catolica do Rio de Janeiro, Rio de Janeiro, RJ 22451900, Brazil

Speaker / Presenter 
Andrade, Ricardo E.

Keywords
experimental methods; networks; particles; particualte systems; polymer solutions; suspensions

Text of Abstract
The synthesis, characterization, modification, and application of two-dimensional (2D) materials, including graphene and its derivatives (such as graphene oxide - GO), and hexagonal boron nitride (hBN), are currently receiving much attention due to their unique properties derived from its nanostructure. These special characteristics lead to innovative and disruptive applications, such as multifunctional nanocomposites, smart materials through 3D/4D printing, conductive inks, among others. However, for these materials to be produced on a large scale, several challenges still exist, namely the fundamental understanding of the rheological behavior of these materials dispersed in different dispersant matrices. In this sense, we have been working on the functionalization of graphene and hBN, dispersed on different model fluids (Polyethylene glycol – PEG, Carbopol and xanthan gum) with the main objective to study the rheological properties during shear flow. It was shown that higher oxidation times increase the functional groups, which leads to a higher dispersion and exfoliation of GO sheets in the PEG. Moreover, the addition of GO in a PEG solution results in significant growth of the suspension viscosity, and a change of the fluid behavior from Newtonian to pseudoplastic. This effect is related to the concentration and oxidation level of the obtained GO particles. However, when the GO was dispersed in Carbopol, promoted a decrease in viscosity, yield stress and elasticity, mostly due to chemical interactions between the 2D material and the model fluid. More recently, the rheological properties of oxidized hexagonal boron nitride (hBN-Oxi) were investigated, and the results revealed that the increase of hBN-Oxi concentration led to a yield stress, well described by the Herschel-Bulkley model. These results provide fundamental insights into rheological response of this 2D materials in complex fluids which is critical for the development of various solution processing and manufacturing techniques.