Definition - What does Nanopore mean?
A nanopore is a void in a solid material that is only several nanometers in diameter. Nanopores can be found in a variety of materials. Certain types of synthetic materials and organic membranes have nanopores. Nanopores are very important attributes of some of coatings and insulation.
Corrosionpedia explains Nanopore
Nanopores can be placed within a synthetic insulation material with a very high density such as silicon. The high density of nanopores in the insulation material allows for a high volume of air entrapped within the insulation without compromising its mechanical properties or permeability. This is useful because highly porous insulation materials can promote even higher amounts of thermal insulation than if the pores were larger and less dense.
The fact that nanopores often leave the insulation material quite impermeable means that there is less concern for foreign liquids and gases reaching the underlying material being insulated. This reduces the risk of corrosion.