Star-shaped macromolecular architectures on Langmuir Blodget monolayers

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Macromolecular engineering offers numerous possibilities to design multifunctional macromolecules of controlled architecture, size and functionality. Within this context the members of the Polymer Lab have synthesized a variety of block copolymers and terpolymers, exhibiting star-shaped architectures. These kind of well-defined highly branched macromolecules have been used as molecular building blocks to create Langmuir Blodget nanostructured monolayers (see below) in a long-lasting strong collaboration with Prof. Vladimir Tsukruk’s group at the Scholl of Materials and Engineering of Georgia Institute of Technology.

Research Highlights

Recently this collaboration, extended with Prof. Sergei Sheiko at the University of North Carolina at Chapel Hill, reported in Nature Materials a new strategy for mixing chemically different (immiscible) macromolecules. It was shown that hydrophobic multiarm star-shaped block terpolymers can finally be mixed with hydrophilic highly branched wormlike bottle brushes at fluid interfaces. It should be underlying that the linear counterparts of these polymers are immiscible. This peculiar molecular intercalation is driven by conformational entropy enhancement, induced by the highly branched architecture of the involved species. This entropic-templating assembly strategy enables long range pattering of thin films on sub-100 nm length scales, with potential applications in multifunctional coatings and enzymatic active surfaces.

Research Highlights

AFM height imaging demonstrates a 50/50 wt% mixture of intercalated PDMA bottlebrushes
 (Mn =2.46x106) and PSn(P2VP-b-PtBA)nheteroarm polymer stars (Mn=7.17x105)

Read more: http://www.nature.com/nmat/journal/v12/n8/pdf/nmat3698.pdf