Polymer film synthesis from an aqueous latex of polymerization-induced self-assembly (PISA) derived nanofibers

Abstract

Polymerization-induced self-assembly (PISA) derived spheres and worms (fibers) comprising poly(n-butyl acrylate) as core-forming block (Tg ≈ −49 °C) were synthesized using a poly(acrylic acid-stat-poly(ethylene glycol) methyl ether acrylate) macroRAFT agent. The nanoparticle morphology varied depending on the pH of the system, i.e. spheres at natural pH (≈ 2.5) and worms at pH 5. The core-sections of the particles (both spheres and worms) were crosslinked using ethylene glycol diacrylate. Films were prepared from the synthesized aqueous latexes via simple drop casting in the absence of volatile organic compounds. The influence of the original nanoparticle morphology on the mechanical properties of the films was subsequently explored – “worm film” displayed 1670 % higher tensile strength and 1290 % higher strain at break compared to “sphere film”. These results demonstrate that film properties can be significantly influenced by the original nanoparticle morphology, despite the nanoparticles comprising very similar polymer chains in terms of composition and molecular weight distribution.