Bicontinuous Network Nanostructure with Tunable Thickness Formed on Asymmetric Triblock Terpolymer Thick FilmsBicontinuous Network Nanostructure with Tunable Thickness Formed on Asymmetric Triblock Terpolymer Thick Films
Asymmetric poly(1,1-dimethyl silacyclobutane)-block-polystyrene-block-poly(2-vinyl pyridine) (PDMSB-b-PS-b-P2VP) thick films, consisting of a spongelike substructure topped by a nanostructured dense top layer, were produced by combining a fast self-assembly of the triblock terpolymer chains with nonsolvent-induced phase separation (referred as SNIPS). A controlled evolution of the thickness and morphology of the nanostructured top layer was achieved upon solvent vapor annealing (SVA). For instance, the sub-100 nm thick square array morphology generated by SNIPS is transformed into a 1.5 μm thick core–shell perforated lamellar (PL) structure when exposed to a chloroform (CHCl3) vapor for 3 h. A PL phase having highly ordered continuous P2VP nanochannels can be envisioned as an appealing morphology for membrane applications, since such a network structure formed on asymmetric PDMSB-b-PS-b-P2VP thick films obviates the need for alignment. Monoliths entirely composed of the bicontinuous PL structure were also produced by increasing the duration of the SVA treatment (18 h, CHCl3).
K. Aissou, M. Mumtaz, H. Bouzit, G. Pécastaings, G. Portale, G. Fleury, G. Hadziioannou
Macromolecules 52, 12, 4413-4420, https://doi.org/10.1021/acs.macromol.9b00572 2019