Shape evolution control of phase-separated colloidal nanoparticles

Abstract

These studies illustrate controlled shape synthesis of two distinct phase-separated copolymers within one colloidal nanoparticle which consists of poly(methylmethacrylate) (p-MMA)/n-butylacrylate (nBA) and poly(nBA)/pentafluorostyrene (p-PFS) phases. Using sequential free radical polymerization, particle morphologies ranging from acorn to ellipsoidal, core–shell, and spherical were produced by adjusting the glass transition temperature (T_g) via compositional gradients during copolymerization. These studies show for the first time that in order to achieve desirable asymmetric particle shapes, the T_g as well as interfacial surface tension between two copolymers within one nanoparticle should be maintained during and after polymerization.