Ion Transport in Nanostructured Phosphonated Block Copolymers Containing Ionic Liquids.
The morphology and conductivity of poly(styrenephosphonate-b-methylbutylene) block copolymers containing ionic liquids are investigated. The block copolymers display a series of well-defined self-assembled morphologies, i.e., lamellae, gyroid, hexagonal cylinder (HEX), body-centered cubic, and A15 lattice, in the absence and presence of ionic liquids. The observation of an equilibrium A15 lattice for linear diblock copolymers, in contrast to a number of theoretical studies, is ascribed to the packing frustration accompanied by prevailing electrostatic interactions. The samples having the A15 lattice show a substantially higher morphology factors (0.83-0.96) than those with the HEX phases (0.42-0.69). This indicates the structural advantage of the A15 lattice with a well-defined 3D symmetry over the 2D HEX structure for constructing less tortuous ion-conduction pathways. This unprecedented study portends the rational design of nanostructured phosphonated polymer membranes with improved conductivity.
Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Ha Young
HY
Jung
Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Onnuri
O
Kim
Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology, Pohang, 790-784, Korea.
Moon Jeong
MJ
Park
D052578:Ionic Liquids / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D063065:Organophosphonates / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*
D052578:Ionic Liquids; D007477:Ions; D063065:Organophosphonates; D011108:Polymers
block copolymers; ionomers; self-assembly; small-angle X-ray scattering; structure-property relations