Inorganic‐Macroion‐Induced Formation of Bicontinuous Block Copolymer Nanocomposites with Enhanced Conductivity and Modulus

Abstract

A facile and electrostatically driven approach has been developed to prepare bicontinuous polymer nanocomposites that is based on the polyoxometalate (POM) macroion induced phase transition of PS-b-P2VP from an initial lamellar phase to a stable bicontinuous phase. The multi-charged POMs can electrostatically cross-link P2VP blocks and give rise to bicontinuous phases in which the POM hybrid conductive domains occupy a large volume fraction of more than 50 %. Furthermore, the POMs can give rise to high proton conductivity and serve as nanoenhancers, endowing the bicontinuous nanocomposites with a conductivity of 0.1 mS cm and a Young's modulus of 7.4 GPa at room temperature; these values are greater than those of pristine PS-b-P2VP by two orders of magnitude and a factor of 1.8, respectively. This approach can provide a new concept based on electrostatic control to design functional bicontinuous polymer materials.

Beyond Charge Balance: Counter‐Cations in Polyoxometalate Chemistry

“…Additionally the composite exhibits high chemical and thermal stability and increased water retention, useful for proton conduction membranes in fuel cells. In a related study, Li and colleagues showed that POM anions can be used to modulate the structure of cationic block copolymer matrices . While the non‐functionalized block copolymer (PS‐ b ‐P2VP, poly(styrene‐ block ‐2‐vinylpyridine)) forms well‐behaved lamellar structures, POM incorporation leads to the formation of bicontinuous nanocomposite structures with phase separation on the <100 nm scale.…”

“…In a related study, Li and colleagues showed that POM anions can be used to modulate the structure of cationic block copolymer matrices. [161] While the non-functionalized block copolymer (PS-b-P2VP, poly(styrene-block-2-vinylpyridine)) forms well-behaved lamellar structures, POM incorporation leads to the formation of bicontinuous nanocomposite structures with phase separation on the < 100 nm scale. The authors suggest that the POM ([SiW 12 O 40 ] 4À ) promotes micellar structures within the block Figure 8.…”

Jenseits von Ladungsausgleich: Gegenkationen in der Polyoxometallat‐Chemie

“…Zudem zeigt das Komposit hohe chemische und thermische Stabilität sowie erhöhte Wasserrückhaltekraft, was nützlich für den Einsatz als protonenleitfähige Membran in Brennstoffzellen ist. In einer damit verbundenen Studie zeigten Li und Mitarbeiter, dass POM‐Anionen genutzt werden können, um kationische Block‐Copolymermatrices zu modifizieren . Während das nichtfunktionalisierte Block‐Copolymer Poly(styrol‐ block ‐2‐vinylpyridin (PS‐ b ‐P2VP) geordnete lamellare Strukturen bildet, führt die POM‐Integration zur Bildung bikontinuierlicher Nanokomposite mit Phasentrennung auf der <100‐nm‐Skala.…”

Confinement of poly(allylamine) in Preyssler-type polyoxometalate and potassium ion framework for enhanced proton conductivity

“…However, application is limited because the structural stability is low and proton conductivity largely decreases upon slight decrease in RH. To solve these problems, POMs have been hybridized with polymers [20][21][22][23][24] especially with those containing amine groups, which serve as protonation sites. While these POM-polymer composites are promising candidates of future solid electrolytes, it is rather difficult to obtain relationship among composition, structure, and property because of the amorphous nature.…”