Length controlled kinetics of self-assembly of bidisperse nanotubes/nanorods in polymers

POLYMER

卷:118

Article

Gooneie, Ali^1,2  Sapkota, Janak¹  Shirole, Anuja³  Holzer, Clemens¹ 

[1] Univ Leoben, Dept Polymer Engn & Sci, Chair Polymer Proc, Otto Glockel Str 2, A-8700 Leoben, Austria

[2] Empa, Lab Adv Fibers, Swiss Fed Labs Mat Sci & Technol, Lerchenfeldstr 5, CH-9014 St Gallen, Switzerland

[3] Univ Fribourg, Adolphe Merkle Inst, Chemin Verdiers 4, CH-1700 Fribourg, Switzerland

关键词: Nanotubes;    Nanorods;    Bidisperse mixtures;    Self-assembly;    Kinetics;    Nanocomposites;    Dissipative particle dynamics;    Cellulose nanocrystals;    Dispersion;   

DOI  :  10.1016/j.polymer.2017.05.010

来源: Elsevier

【 摘 要 】

While there is a growing body of work that supports the self-assemblies of nanotubes and nanorods, little attention has been devoted to understand the relation between their length and the kinetics of self assembly in polymer composites. Using dissipative particle dynamics (DPD) method, we simulated the temporal developments of equilibrium microstructures of nanotube dispersions with a bimodal length distribution in polymer matrix. The nanotube/polymer models were developed with different sets of interactions between the components. The equilibrium morphologies obtained for nanotubes are in good agreement with those proposed by previous experimental and theoretical studies. We found that long nanotubes could self-assemble into ordered honeycomb-like bundles as validated with the structure factor calculations. The self-assembly kinetics was quantitatively estimated at different stages and length scales using the variations in the pair-correlation functions. It was observed that the kinetics slowed down particularly in the initial stages of the self-assembly. This was mainly ascribed to the spatial interferences of bidisperse nanotubes as evidenced by laser scanning microscopy and simulated mean squared-displacements (MSD). Furthermore, the developed microstructures were assessed in terms of the effective nanotube volume derived from Monte Carlo (MC) calculations and the frequency of nanotube-nanotube contacts. The simulations reported herein contribute to a microscopic interpretation of the literature results, and the findings of this paper contribute meaningfully to the design strategies aimed at achieving novel nanocomposites with optimal physical properties. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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