Mechanochemistry unveils stress transfer during sacrificial bond fracture of tough multiple network elastomers.

ABSTRACT: The molecular level transfer of stress from a stiff percolating filler to a stretchable matrix is a crucial and generic mechanism of toughening in soft materials. Yet the molecular details of how this transfer occurs have so far been experimentally unreachable. Model multiple network elastomers containing spiropyran (SP) force sensors incorporated into the stiff filler network or into the stretchable matrix network are used here to detect and investigate the mechanism of stress transfer between distinct populations of polymer strands. We find that as the filler network progressively breaks by random bond scission, there is a critical stress where cooperative bond scission occurs and the macroscopic stretch increases discontinuously by necking. Surprisingly, SP molecules reveal that even in

SUBMITTER: Chen Y 

PROVIDER: S-EPMC8386638 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature