Metal and plastic vessels and other leakproof shells are vulnerable to punctures and other damages.
To increase reliability, it is necessary to make their walls thicker, which increases the weight and cost of products. How can this contradiction be resolved?

One of the possible ways is using self-regenerating materials.
Shells are manufactured from a special plastic material with uniformly distributed microcapsules of epoxy resin and hardener. When the shell is damaged, capsules in the place of the damage burst and the resin flows out of them filling a crack or a scratch. This is accompanied by a chemical reaction with the hardener and some time later the tightness restores.
If the Russian space station “Mir” had been made of such a material, then the occurring micro cracks would not have done harm to it and it would not have been buried in the ocean. 
 

By “Bild der Wissenschaft”.