Functionalized carbon nanotubes with polystyrene-block-poly (N-isopropylacrylamide) by in situ RAFT polymerization

A fascinating nano-object, amphiphilic polymer brushes with a hard core of multiwalled carbon nanotubes ( MWNTs) and a relatively soft shell of polystyrene-block-poly ( N-isopropylacrylamide) ( PS-b-PNIPAM), was easily constructed by in situ surface reversible addition-fragmentation chain transfer ( RAFT) polymerization of styrene followed by N-isopropylacrylamide on the modified convex surfaces of MWNTs ( MWNT-PS). The structure and morphology of the as-prepared hybrid nanomaterials were characterized and confirmed by Fourier-transform infrared ( FTIR) spectrometry, nuclear magnetic resonance ( NMR) spectrometry, thermogravimetric analysis ( TGA) and Raman spectroscopic analysis. The MWNT-PS-b-PNIPAM that was produced has a PNIPAM block, which is very sensitive to temperature. Such a complex nano-object could open a door to the fabrication of novel functional carbon nanotube-based nanomaterials or nanodevices with designable structures and tailor-made properties.