Polymer materials exhibit numerous useful
characteristics at multiple length scales, from the angstrom scale
(atom-to-atom bonding) to the nanoscale (interactions of groups of atoms) to
the macroscale (collective properties of large objects). McCarthy, working in the Materials
Reseach Science and Engineering Center on Polymers at UMass, showed that
silicon-containing polymers, termed siloxanes, undergo self-healing events that
allow a variety of shaping and re-shaping events, such as the “dog bone” to
“dog” transition shown in the picture.
Importantly, pristine mechanical properties are maintained in all of the
shapes, due to the ability of the siloxane bonding structure to heal during
processing.