writer：Nan Yan,?,? Yuping Sheng,?,§ Hongxia Liu,?,§ Yutian Zhu,*,? and Wei Jiang*,?
keywords：self-assembly in pore
source：期刊
specific source：Langmuir
Issue time：2015年
In the current study, we investigate the selfassembly
of polystyrene-block-poly(4-vinylpyridine) (PS-b-
P4VP) confined in the nanopores of the anodic aluminum
oxide (AAO) template and the subsequent morphology
transformation induced by the Rayleigh instability. PS-b-
P4VP nanotubes and nanorods with various internal
nanostructures are fabricated by wetting the AAO template
with PS-b-P4VP/chloroform solution, and then followed by
solvent evaporation. After the removal of AAO template by
potassium hydroxide solution, several different solvents
(chloroform, toluene, and N,N-dimethylformamide) with
different qualities are used to swell and anneal those nanotubes
and nanorods suspended in aqueous media. Morphology
transformation from nanostructured PS-b-P4VP nanotubes or nanorods to ordered nanospheres is observed by annealing upon
chloroform and toluene while the morphology remains unchanged upon N,N-dimethylformamide annealing, indicating that
solvent quality is a key factor in tuning the morphology and internal structures. Kinetics study and theoretical analysis for the
morphology transition from two-dimensional (2D) block copolymer (BCP) nanotubes and nanorods to three-dimensional (3D)
BCP nanospheres are further performed. From the morphological evolution and the quantitative calculation, it is confirmed that
this transition is induced by the Rayleigh instability. This study provides a simple but promising method, that is, solvent
annealing method, for the fabrication of BCP nanospheres with ordered internal nanostructures, which may have great
application in drug delivery and other nanotechnology.