Initial Solvent Induced Non-Equilibrium Effect of Polymer Nanocomposites

Since the degree of particle dispersion can determine the physical properties of polymer nanocomposites (PNCs), plenty of studies have focused on the intrinsic parameters of PNCs such as the concentration/size/chemistry of nanoparticles/polymers relevant to the particle microstructure. While the consideration of these parameters is based on PNCs being in their equilibrium states, PNCs can be kinetically trapped in a nonequilibrium state during the multiple steps of processing. In other words, processing conditions can contribute more significantly to particle dispersion and the properties of PNCs beyond the effects of the intrinsic parameters.

In this talk, I am going to share our recent research outcomes on how the initial dispersing solvent can induce different structures and properties of PNCs. Employing extensive small-angle scattering, proton NMR spectroscopy, and rheometry experiments, my group has found the initial solvent can alter the nature of interfacial layers, often changing the adsorption behaviors. This initial solvent-induced effect can persist even more than a few years and can be enhanced in the case of smaller particles. In addition, the initial solvent-induced non-equilibrium effect is also discussed for chemically grafted polymer systems.