414984 Block Copolymer Bottlebrushes: New Routes to Ever Smaller Microdomain Sizes

Thursday, November 12, 2015: 12:30 PM
251C (Salt Palace Convention Center)
Mahesh Mahanthappa, Department of Chemical Engineering & Materials Science, University of Minnesota, Minneapolis, MN

Block copolymer self-assembly at the nanoscale presents tremendous opportunities for the development of new nanotemplates for advanced lithography applications, wherein the homopolymer-rich microdomain sizes (~ 10–100 nm) are governed by the total copolymer degree of polymerization, N. However, this methodology is limited in its smallest achievable length scale, since AB diblock copolymers self–assemble only above a critical N that depends inversely on the magnitude of the interaction parameter χAB, which quantifies the energetic repulsions between the dissimilar homopolymer segments. Numerous recent reports have focused on developing “high χAB” AB diblocks that self–assemble at low values of N. In this talk we explore the ability of non-linear polymer architectures to induce block copolymer ordering at reduced length scales. Thus, we describe the melt and thin film self-assembly behavior of block copolymer bottlebrushes derived from linking the block junctions of low molecular weight AB diblocks. We quantitatively demonstrate that increasing the bottlebrush backbone degree of polymerization (Nbackbone) results in as much as a 75% reduction in the critical copolymer arm degree of polymerization (Narm) required for self-assembly, thus reducing the length scales at which these materials self-assemble.

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See more of this Session: Inhomogeneous Polymers
See more of this Group/Topical: Materials Engineering and Sciences Division