Currently, there is no reported work on anionic polymerized
nylon 6/CNF nanocomposites/composites and very limited literature
on the use of stacked-cup CNFs to reinforce/toughen thermoplastics
[9,11,12]. We hypothesized that with adequate surface
chemistry, stacked-cup CNFs could act as not only efficient
reinforcing fibers, its ability to unravel and bridge cracks could also
aid the toughening of nylon 6 to some extent. To promote dispersion
of the CNFs in nylon 6 and achieve adequate interfacial
interactions, there is a need for chemical modification of the CNF
surface. Thus, in this work, initiation sites were built on the surface
of the CNFs for in situ anionic ring-opening polymerization of e-caprolactam (CL) to yield covalently bonded nylon 6 chains on
the surface of CNFs. It is aimed at reinforcing nylon 6 by aptly adding
stacked-cup CNFs at very low loadings without sacrificing
toughness of the system; ultimately benefiting the advancement
of fabrication of large thermoplastic composites via reactive processing.
Herein, the results on the functionalization of stackedcup
CNFs, morphology and properties of the nylon 6/stacked-cup
CNF nanocomposites prepared via the in situ anionic ring-opening
polymerization will be discussed to demonstrate the effectiveness
of our approach.