Electrospinning is the only direct and efficient method to continuously
produce ultra-fine fiber with diameter of 10-1000nm. More than 250 kinds
of polymer nanofiber types have been successfully developed.
Nanometer (1nm=10-9m) and micrometer (1nm=10-6m) are units of length,
which are often used to express dimensions in tiny scale.
The following pictures are the size comparison among nanofibers, human hair
and compound eyes of an ant. The result shows that nanofibers are more smaller
than the others. The nanofiber has many advantages, like high specific surface area,
high active ability for modification, small diameter and large porosity.
