title: Hybrid self-healing matrix using core-shell nanofibers and capsuleless microdroplets.
abstract: In this work, we developed novel self-healing anticorrosive hierarchical coatings that consist of several components. Namely, as a skeleton we prepared a core-shell nanofiber mat electrospun from emulsions of cure material (dimethyl methylhydrogen siloxane) in a poly(acrylonitrile) (PAN) solution in dimethylformamide. In these nanofibers, cure is in the core, while PAN is in the shell. The skeleton deposited on a protected surface is encased in an epoxy-based matrix, which contains emulsified liquid droplets of dimethylvinyl-terminated dimethylsiloxane resin monomer. When such hierarchical coatings are damaged, cure is released from the nanofiber cores and the resin monomer, released from the damaged matrix, is polymerized in the presence of cure. This polymerization and solidification process takes about 1-2 days and eventually heals the damaged material when solid poly(dimethylsiloxane) resin is formed. The self-healing effect was demonstrated using an electrochemical analogue of the scanning vibrating electrode technique. Damaged samples were left for 2 days. After that, the electric current through a damaged coating was found to be negligibly small for the samples with self-healing properties. On the other hand, for the samples without self-healing properties, the electric current was significant.
authors.affiliation: School of Mechanical Engineering, §Green School, and ⊥College of Engineering, Korea University , Seoul 136-713, Republic of Korea.
authors.forename: Min Wook
authors.initials: MW
authors.lastname: Lee
authors.forename: Seongpil
authors.initials: S
authors.lastname: An
authors.forename: Changmin
authors.initials: C
authors.lastname: Lee
authors.forename: Minho
authors.initials: M
authors.lastname: Liou
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Yarin
authors.forename: Sam S
authors.initials: SS
authors.lastname: Yoon