Dang Minh Triet, Truong Quoc Tuan, Tran Van Thien

Main Article Content

Abstract

Colloidal gels are space-spanning networks that form solids at dilute particle volume fractions. The kinetic process of gelation is central to understand the flow of complex fluids. Here, we report a simulation study of colloidal gelation of anisotropic colloids with attractive Lennard-Jones potential. These forces quasi-model the critical Casimir effect far from the critical solvent fluctuations acting on colloidal patches. By tuning the depths of the patch-to-patch particle interactions and the selected colloidal patches, we dynamically arrest the colloids to form gels. We find that thermal density fluctuation is the key factor to activate colloidal cluster space spanning: the balance between clustering and break-up mechanism is important for the gelation process of anisotropic systems. These results open new opportunities for studying the structural modifications of colloidal gels formed by anisotropic particles, and shed light on non-equilibrium behavior of anisotropic colloidal building blocks.

Keywords: Gelation, anisotropic colloids, short-range attraction.

References

V. Trappe, P. Sandkhler, Colloidal gels – low-density disordered solid-like states, Curr. Opin. Colloid Interface Sci. 8 (2004) 494–500. https://doi.org/10.1016/j.cocis.2004.01.002
[2] L. Cipelletti, S. Manley, R.C. Ball, D. Weitz, Universal Aging Features in the Restructuring of Fractal Colloidal Gels, Phys. Rev. Lett. 84 (2000) 2275–2278. https://doi.org/10.1103/PhysRevLett.84.2275
[3] S. Manley, et al. Time-Dependent Strength of Colloidal Gels, Phys. Rev. Lett. 95 (2005) 48302. https://doi.org/10.1103/PhysRevLett.95.048302
[4] S. Jabbari-Farouji, et al., High-bandwidth viscoelastic properties of aging colloidal glasses and gels, Phys. Rev. E 78 (2008) 61402. https://doi.org/10.1103/PhysRevE.78.061402
[5] P.G. Debenedetti, F.H. Stillinger, Supercooled liquids and the glass transition, Nature 410 (2001) 259–267. https://doi.org/10.1038/35065704
[6] A. Zaccone, H.H. Winter, M. Siebenbarger, M. Ballauff, Linking self-assembly, rheology, and gel transition in attractive colloids, J. Rheol. 58 (2014) 1219–1244. https://doi.org/10.1122/1.4878838
[7] P.B. Shelke, V.D. Nguyen, A. V. Limaye & P. Schall, Controlling colloidal morphologies by critical casimir forces, Adv. Mater. 25 (2013) 1499–1503. https://doi.org/10.1002/adma.201204458
[8] V.D. Nguyen, S. Faber, Z. Hu, G.H. Wegdam, P. Schall, Controlling colloidal phase transitions with critical Casimir forces, Nat. Commun. 4 (2013) 1584. https://doi.org/10.1038/ncomms2597
[9] M.T. Dang, A.V. Verde, V.D. Nguyen, P.G. Bolhuis, P. Schall, Temperature-sensitive colloidal phase behavior induced by critical Casimir forces, J. Chem. Phys. 139 (2013) 94903. https://doi.org/10.1063/1.4819896
[10] T. Narayanan, A. Kumar, E.S.R. Gopal, A new description regarding the approach to double criticality in quasi-binary liquid mixtures, Phys. Lett. A 155 (1991) 276–280. https://doi.org/10.1016/0375-9601(91)90482-N
[11] D. Beysens, T. Narayanan, Wetting-induced aggregation of colloids, J. Stat. Phys. 95 (1999) 997–1008. https://doi.org/10.1023/A:1004506601807
[12] J.D. Cox, Phase relationships in the pyridine series. Part II. The miscibility of some pyridine homologues with deuterium oxide. J. Chem. Soc. (1952) 4606–4608. https://doi.org/10.1039/JR9520004606
[13] C. Hertlein, L. Helden, A. Gambassi, S. Dietrich, C. Bechinger, Direct measurement of critical Casimir forces, Nature 451 (2008) 172–175. https://doi.org/10.1038/nature06443
[14] M. Orsi, Comparative assessment of the ELBA coarse-grained model for water, Mol. Phys. 112 (2014) 1566–1576. https://doi.org/10.1080/00268976.2013.844373
[15] S. Plimpton, Fast Parallel Algorithms for Short-Range Molecular Dynamics, J. Comput. Phys. 117 (1995) 1–19. https://doi.org/10.1006/jcph.1995.1039