Effects of Lithium Salts on the Domain Size of Polyethylene Oxide Containing Block Copolymers

ORAL

Abstract

The morphology of block copolymers with and without lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salts are measured with small-angle x-ray scattering (SAXS). The block copolymers comprise of polyethylene oxide (PEO), a polymer with a higher dielectric constant that dissolves LiTFSI, and polystyrene (PS), a polymer with a lower dielectric constant that does not dissolve LiTFSI. Due to the hygroscopic nature of the salts, blend preparation is performed completely in a glovebox and the SAXS samples are sealed off in airtight sample holders. To ensure that moisture contamination does not affect morphology, Karl-Fischer titrations are performed after SAXS measurements. Our data will be compared with literature results that indicate a 300{\%} increase in the domain spacing of PEO-containing block copolymers spacing due to the addition of LiTFSI.

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Authors

  • Nisita Wanakule

    UC Berkeley, Univ. of California, Berkeley

  • Scott Mullin

    UC Berkeley

  • Nitash Balsara

    UC Berkeley, Lawrence Berkeley National Laboratory, University of California, Berkeley, University of California, Berkeley, Department of Chemical Engineering, University of California, Berkeley, California 94720, U. C. Berkeley, Univ. of California, Berkeley