Mechanical Reinforcement in Polymer Melts Filled with Polymer Grafted Nanoparticles.

We critically leverage the fact that polymer grafted nanoparticles behave akin to block copolymers to systematically vary nanoparticle dispersion and critically examine its role on the mechanical reinforcement in liquid-polymer-based nanocomposites. The nanoparticles are noncontacting, and we perform rheological measurements 80K above the polymer’s glass transition temperature. Our rheology results unequivocally show that reinforcement is maximized by the formation of a transient, but long-lived, percolating polymer–particle network with the particles serving as the network junctions. [ABSTRACT FROM AUTHOR]