Self healing polymer rebonds after cutting

A new material can rebond itself when cut and retain elasticity. Rubbersied materials gets their elasticity from long chains of polymer molecules that are crosslinked in three different ways: through covalent, ionic, and hydrogen bonding between molecules. Of these three bond types, only the hydrogen bonds can be remade once a material is fractured, although normally there are not enough hydrogen bonds available to re-couple in this way. Rebonding can be achieved after breaking or cutting by devising a material that gets rid of the ionic and covalent bonds in faour of hydrogenic only.

See New Scientist.
and on YouTube: video of cutting and mending