Wrapping amino-bearing block copolymer cylinders around carboxyl-bearing nanofibers: a case of hierarchical assembly

Abstract

Poly(2-cinnamoyloxyethyl methacrylate)-block-poly(tert-butyl acrylate) (PCEMA-b-PtBA) formed cylindrical micelles in methanol, a selective solvent for PtBA. Photo-crosslinking the PCEMA core yielded structurally stable nanofibers. Hydrolyzing the coronal PtBA chains then produced nanofibers bearing surface carboxyl groups. Poly(tert-butyl acrylate)-block-poly(2-cinnamoyloxyethyl methacrylate)-block-poly(N,N-dimethyl aminoethyl methacrylate) (PtBA-b-PCEMA-b-PDMAEMA) self-assembled into cylindrical micelles in methanol, a block-selective solvent for the terminal PtBA and PDMAEMA blocks. These micelles, with either crosslinked or non-crosslinked PCEMA cores, form the amino-bearing nanocylinders. This paper reports the wrapping of the nanocylinders around the nanofibers to form solvent-dispersible composite “nanoropes”, when the two nanostructures were mixed at appropriate mass ratios. Also reported is the chain rearrangement of the slightly crosslinked nanocylinders on the nanofiber surfaces to eventually yield multilayered composite cylinders.