Revealing Structures and Dynamics of Bound Chains in Filler-Reinforced Elastomers

Filler-reinforced elastomershave been of great interest to the broad materials community for at least the last three decades. The addition of nanofillers such as carbon black or silica to elastomers affects the overall rheological and mechanical properties mainly due to the creation of a few nanometer-thick bound polymer layer (BPL) on a filler surface at which the polymer is expected to have different structural and dynamical behavior from the bulk. However, the detailed descriptions of the BPL remain a challenge due to the lack of experimental techniques that directly probe the BPL. In this presentation, using simplified industrialcarbon black (CB) filled polybutadiene in conjunction with contrast-matched neutron scattering and spectroscopy techniques, we resolve the buried structure at the nanometer-scale and the dynamics at the picosecond-to-nanosecond time scales in the polymer matrix.