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

A facile and electrostatically-driven approach has been developed to prepare bicontinuous polymer nanocomposites, through 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 crosslink P2VP blocks and lead to bicontinuous phases in which the POM-hybrid conductive domains occupy a large volume fraction more than 50 %. Furthermore, POMs can serve as both high proton conductors and nanoenhancers, endowing the bicontinuous nanocomposites with a conductivity of 0.1 mS cm-1 and a Young's modulus of 7.4 GPa at room temperature, which are 2 orders of magnitude and 1.8 times enhanced respectively, compared with the pristine PS-b-P2VP. This approach can provide a new concept based on electrostatic control to design functional bicontinuous polymer materials.