Abstract

The shear-induced ordering of composite polymer nanoparticles is a relatively new paradigm in the generation of nano-ordered materials over large areas and volumes [1]. The hard-core/soft-shell design of these sub-micron spherical particles produces quasi-solid “gum-like” media, with a viscoelastic ensemble response to applied shear, in marked contrast to the behaviour seen in colloidal and granular systems [2]. Applying an oscillatory shearing method produces monotonic crystallization processes [3] to give elastomeric photonic crystals (or “polymer opals”) with characteristic close packing geometries, and intense tuneable structural colour [4]. Developing a controllable “roll-to-roll” process known as BIOS , or Bending Induced Oscillatory Shear [5], and the interchangeable nature of the base composite materials, opens potentially transformative possibilities for mass manufacture of advanced optical materials, photonics, and plasmonics.   [1] C.E. Finlayson and J.J. Baumberg, Polymer International 62, pp.1403–1407 (2013) [2] D.R.E. Snoswell et al., Phys. Rev. E 92 , 052315 (2015) [3] C.E. Finlayson, G. Rosetta, and J.J. Baumberg, Materials 14, 5298 (2021) [4] G. Rosetta et al., Optics Express 28, pp.36219 (2020) [5] Q. Zhao et al., Nature Communications 7, 11661 (2016)