Syntheses of Mesostructured Silica Films Containing Conjugated Polymers from Tetrahydrofuran−Water Solutions

Abstract

Co-self-assembly of mesostructured silica films from solutions of tetrahydrofuran (THF) and water, silica precursor species, and structure-directing Pluronic P123 block-copolymer molecules is reported with and without conjugated polymer guest species. The solution-phase behavior of the ternary THF-water-P123 system guided the selection of nonequilibrium synthesis conditions that allowed highly ordered 2D hexagonal or lamellar mesostructured silica to be prepared. Dilute water molecules produced in situ by silica condensation were necessary and sufficient to promote P123 self-aggregation into micelles and ultimately liquid crystal-like inorganic-organic mesophases as the THF evaporated. Solid-state twodimensional 13 C{ 1 H} and 29 Si{ 1 H} NMR characterization of the product film materials revealed highly mobile block copolymer components at room temperature and preferential interactions of poly(ethylene oxide) moieties with the silica framework at 260 K. Solution processing in THF permitted highly hydrophobic, high molecular weight, conjugated polymers to be directly coassembled within the mesostructured inorganic-organic host matrices during their formation. The incorporated conjugated polymers exhibited semiconducting properties and enhanced environmental photo-stability that may be exploited in electronic and optoelectronic devices.

Original Fuel‐Cell Membranes from Crosslinked Terpolymers via a “Sol–gel” Strategy

“…This can favor the formation of lamellar objects. Kirmayer et al [40] studied the solution-phase behavior of the ternary THF-water-P123 system and showed that adding THF to water-P123 mixtures can induce H1-L a transitions at high P123:water ratios, which supports the presence of a lamellar mesostructure in the present hybrid membranes with 62 wt% P123 loadings. The water uptake is closely related to the membrane behavior.…”

Enhanced and tunable photoluminescence of polyphenylenevinylenes confined in nanocomposite films

“…This peculiarity is an inherent characteristic of the hybrid nanocomposites based on CP and mesoporous silica or layered inorganic matrices, which were reported in the previous literature [13][14][15][16][17][18][19]21,[24][25][26].…”

“…The effect was achieved when the CP macromolecule is inserted inside the cavities of different 2D and 3D non-conductive porous matrices [13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Such hybrid nanocomposites were prepared by embedding CP macromolecules inside the pre-synthesized mesoporous particles [13][14][15][16][17][18] and films [19,20], also using an in situ method, i.e., during film formation [21,22], in the latter case. The procedure of exfoliation followed by successive adsorption of CP was used for layered matrices [7,[23][24][25][26].…”

Detection and use of small J couplings in solid state NMR experiments

“…10 ppm, full width at half maximum [fwhm]) 29 Si NMR lineshapes (Fig. 1e) that barely allow resolution of chemically different Q 3 (i.e., (SiO) 3 Si-OH or (SiO) 3 Si-O -) and fully condensed Q 4 (Si(SiO) 4 ) 29 Si moieties. Similar molecularly-disordered SiO 2 structures are also generally found in the walls of self-assembled mesoporous silica despite potentially high degrees of long-range order in their pore architectures, as illustrated on Fig.…”