Isocyanate-functionalised graphene oxide and poly(vinyl alcohol) nacre-mimetic inspired freestanding films.

Nacre mimetic films based on 2-ureido-4[1]-pyrimidinone (UPy) functionalised graphene oxide (GO) and poly(vinyl alcohol) (PVA) were readily prepared by self-assembly using a vacuum filtration method. The isocyanate (UPy) functionalisation of the PVA was confirmed from a combination of Fourier transform infrared spectroscopy (FTIR) and changes in -spacing from X-ray diffraction (XRD) measurements and, of the GO by solid-state NMR measurements reported by the authors previously. This is the first example of nacre mimetic structures where both the nanoplatelet (GO) and polymer (PVA) components are functionalised with complimentary groups.