An adaptive material has been invented recently which combines self-healing and reversible self-stiffening properties.
The material called SAC (for self-adaptive composite) consists of what amounts to sticky, micron-scale rubber balls that form a solid matrix.
The researchers made SAC by mixing two polymers and a solvent that evaporates when heated, leaving a porous mass of gooey spheres. When cracked, the matrix quickly heals, over and over and like a sponge, it returns to its original form after compression.
In SAC, tiny spheres of polyvinylidene fluoride (PVDF) encapsulate much of the liquid. The viscous polydimethylsiloxane (PDMS) further coats the entire surface.
The study has been published in ACS Applied Materials & Interfaces.