Shape evolution control of phase-separated colloidal nanoparticles

Cathrin C. Corten, University of Southern Mississippi
Marek W. Urban, University of Southern Mississippi

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.