  The recent development of nanoscale fillers, such as carbon nanotube,
graphene, and nanocellulose, allows the functionality of polymer nanocomposites
to be controlled and enhanced. However, conventional synthesis methods of
polymer nanocomposites cannot maximise the reinforcement of these nanofillers
at high filler content. Approaches to the synthesis of high content filler
polymer nanocomposites are suggested to facilitate future applications. The
fabrication methods address design of the polymer nanocomposite architecture,
which encompass one, two, and three dimensional morphology. Factors that hamper
the reinforcement of nanostructures, such as alignment, dispersion of filler as
well as interfacial bonding between filler and polymer are outlined. Using
suitable approaches, maximum potential reinforcement of nanoscale filler can be
anticipated without limitations in orientation, dispersion, and the integrity
of the filler particle-matrix interface. High filler content polymer composites
containing emerging materials such as 2D transition metal carbides, nitrides,
and carbonitrides (MXenes) are expected in the future.
