Dissipative particle dynamics studies on the interface of incompatible A/B homopolymer blends in the presence of nanorods

Dissipative particle dynamics (DPD) simulations are used to investigate the effect of nanorods on the interface of immiscible A/B homopolymer blends. The nanorods are constructed by a string of beads connected through the spring forces, and then their rigidity is achieved depending on the angle forces. For the low volume fraction and/or aspect ratio, nanorods lead to broaden the interfacial width, D and decrease the interfacial tension, γ_S with the increase of the volume fraction. There is also a pronounced linear relationship. For the high volume fraction and/or aspect ratio, the variation of D and γ_S is found to depend on Onsager's dimensionless parameter ψν, where ψ and ν are the volume fraction and aspect ratio of nanorods in the systems, respectively. Two scaling D ∼ (ψν)³ and γ_S ∼ (ψν)² are constructed. These results indicate that nanorods can indeed be used as a compatibilizing agent of immiscible blends as mentioned in reference [J. Chem. Phys. 2008, 128, 054901] and improve the interfacial characteristics, only when the parameters (ψν) in the correct range are chosen.