Phase Behaviors and Bridging Properties of Bolaform Tethered Nanoparticles

Abstract

We investigate the bolaform tethered nanoparticles (P-H-P) in melt by using a computational method combining the self-consistent field theory for the flexible homopolymer (H) and the density functional theory for two hard spheres (P) chemically connected at each end of the homopolymer. The phase diagram of P-H-Ps is highly asymmetric even for the symmetric P-H-Ps with two identical nanoparticles. When the size difference between two particles is large enough, the P-H-Ps forming lamellae undergo a transition from the particle-aggregated state to the particle-separated state with increasing volume fraction fA of polymer or increasing Flory–Huggins parameter χ between the polymer and the particles. Compared with the linear ABA triblock copolymers with the same molecular size and component fractions, P-H-Ps have much higher fractions vB of the bridging conformation connecting two domains apart in distance. The bridging fraction vB, which is believed to be significant to the mechanical properties of the polyme...