A New Direction of Polymer Nanocomposite: Polymer Infiltrated Scaffold Metals*

Polymer composites have been widely studied because of their outstanding properties. Typically, polymer nanocomposites (PNC) are fabricated by adding inorganic nanofillers to a polymer matrix. In this work, a high-filler PNC is created by infiltrating polystyrene (PS) or poly(2-vinylpyridine) (P2VP) into a nanoporous gold scaffold exhibiting a bicontinuous structure and nanoscale pores. Infiltration occurs through capillary forces by heating PS (P2VP) above its glass transition temperature. PS and P2VP, having different affinities to the gold scaffold, exhibit different segmental dynamics inside the confined pores as measured through Tg. The more attractive P2VP shows a 20°C increase in Tg while PS shows only a 6°C increase at a comparable molecular weight. The effect of molecular weight on infiltration kinetics is presented with P2VP exhibiting longer infiltration time compared to PS having a similar molecular weight. The interconnected structure of these composites could facilitate high ion (electron) conductivity, thus enabling enhanced performance for batteries and flexible electronics.