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Creators/Authors contains: "Karavolias, Michael G."

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  1. We report the synthesis and temperature-dependent morphologies of a series of polylactide-block-poly (ฮต-decalactone)-block-polylactide (LDL) triblock copolymers with ๐‘€๐‘›=16.0โ€“18.1โขkg/mol and volume fractions ๐‘“L=0.27โ€“0.31 and associated core-shell bottlebrush (csBB) polymers, which derive from enchaining LDL triblocks through a polymerizable midchain functionality. While the LDL triblocks form micellar Frank-Kasper A15 and ฯƒ phases due to the conformational asymmetry of this monomer pair, the csBB morphologies sensitively depend on the backbone degree of polymerization (๐‘bb). At low ๐‘bb values, micellar Frank-Kasper phases with the brush backbone situated in the matrix domain are stable, albeit with a modest reduction in the mean interfacial curvature evidenced by a ฯƒ to A15 order-to-order transition. However, larger ๐‘bb values drive csBBs to form hexagonally packed cylinders phases. This ๐‘bb-dependent phase behavior is rationalized in terms of a star-to-bottlebrush transition. At low ๐‘bb values, the csBBs are akin to star polymers with pointlike junctions that can support complex micelle packings. As ๐‘bb increases, the csBBs adopt cylindrical molecular geometries with extended backbones situated in the matrix domain that prefer hexagonally packed cylinders morphologies. 
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