Thermoreversible gels of hollow silica nanorod dispersions

Published

May 1, 2024

Author(s)

Haesoo Lee, KHUSHBOO SUMAN, David Moglia, Ryan Murphy, Norman Wagner

Abstract

Colloidal suspensions of anisotropic particles are ubiquitous in particle-based industries. Consequently, there is a need to quantify the effects of particle shape on equilibrium phases and kinetic state transitions, particularly at lower aspect ratios (L/D ≈ 1-10). We present a new, colloidal system comprised of hollow, octadecyl-coated silica rods with 40nm diameter with controlled aspect ratio and thermoreversible short-range attractions. Rheology and dynamic light scattering measurements on suspensions of these hollow adhesive hard rods with nominal aspect ratio ≈3 suspended in tetradecane exhibit thermoreversible gelation without complicating effects of gravitational settling. Small angle neutron scattering measurements of the microstructure are analyzed to determine the effective strength of attraction in the form of Baxter sticky parameter. Quantitative agreement is found with simulation predictions of the thermoreversible gel transition as a function of volume fraction, further validating a universal state diagram and providing guidance for the effects of aspect ratio on gelation.

Citation

Journal of Colloid and Interface Science

Volume

661

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.jcis.2024.01.148

Local Download

Citation

Lee, H. , SUMAN, K. , Moglia, D. , Murphy, R. and Wagner, N. (2024), Thermoreversible gels of hollow silica nanorod dispersions, Journal of Colloid and Interface Science, [online], https://doi.org/10.1016/j.jcis.2024.01.148, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956839 (Accessed December 13, 2024)