Whenever I see the term ‘self-healing’ my bullshit meter immediately alarms, however Nissan has produced a self-healing iPhone case with some awesome materials science to back it up. The case is expected to be distributed later this year, so I haven’t gotten my wanting (and clumsy) hands on one myself. To me this is a ‘when I see it, I will believe it’ situation, but the science is intriguing.
Nissan originally invested in the development to form a self-healing car paint, however now they have transformed it into an iPhone case. The self-healing car paint is already on several current Nissan models including the Murano, 370Z, and the X-Trail. The caveat is its limitations to heal only ‘fine’ scratches.
The case consists of polyrotaxane. The name rotaxane derives from the Latin name rota (wheel) and axis (axel). Rotaxane is a chemical compound looks like a dumbbell with a macrocyclic ring trapped between the two ends. Polyrotaxane, the polymeric form, is a dumbbell with many rings around it.
In the scientific literature, there are many chemical variations in the blue dumbbell structure and in the green macrocyclic ring. The diversity in chemical structure probably results in various applications of this class of compounds. Mechanistic details were scarce, but it is a class of compounds I plan to keep my eye on.