Polymer Interfaces: Synthetic Strategies Enabling Functionality, Adaptivity, and Spatial Control

Abstract

Polymer interfaces are ubiquitous in Nature and technology. Equipping artificial polymer-based interfaces with highly defined functions requires advanced macromolecular chemistry and powerful chemical tools. In this Perspective, we explore the nature of anisotropici.e., spatially resolved polymer interfaces prepared via top-down and bottom-up approaches with selected examples from the recent literature. These range from self-assembly driven systems based on single polymer chains and block copolymers to lithographic encoding able to span wide spatial dimensions of patterning. Based thereon, we formulate the in our opinion required advances in polymer chemistry that will contribute significantly to preparing the next generation of structured interfaces. Among others, this includes the to-date limited orthogonality of parallelly executed ligation reactions as well as limits in λ-orthogonally addressable pericyclic ligation chemistry. Finally, we propose some long-term visions for not yet existinghowever currently soughttechnology that could drive interactive and adaptive polymer interface construction to new levels. These include the spatially resolved encoding of interfaces with molecular precision and the introduction of programmable properties to interfaces of varying shape and chemical complexity.

Coding and decoding libraries of sequence-defined functional copolymers synthesized via photoligation

“…For potential data storage applications, solid support-based systems have emerged featuring monomer units with unreactive variable alkyl groups47 and block copolymer phase separation based on sequence-defined oligomers has been demonstrated as well36. The herein proposed synthetic strategy based on photoreactive synthons offers significant applications of the functional sequence-defined macromolecules ranging from mild bioconjugation to base materials for advanced precision photoresists for, for example, direct laser writing48 or precision network formation for nuclear magnetic resonance (NMR) orientation media4950. Critically, photochemistry offers the opportunity to broaden the chemical diversity in the design of sequence-defined macromolecules.…”

Seeing the Light: Advancing Materials Chemistry through Photopolymerization

“…As a result, precise activation of polymerization in specific regions via light irradiation can allow synthesis of new materials with unprecedented properties. Although the use of living photopolymerization methods for the functionalization of surfaces is still in its infancy, the application of polymer films on surfaces can already be seen within the shipping, water treatment, computer, and solar industries; a review by Barner‐Kowollik and co‐workers highlights some of the synthetic strategies and applications of spatial control for photopolymerization systems …”

Micellization of Photo-Responsive Block Copolymers

“…Both can be precisely adjusted by molecular parameters such as molar mass, volume fraction of the respective segments, overall architecture, and also segment rigidity (this also includes the presence of crystallizable blocks). Additional elements of control include strategies to influence the self-assembly process itself (“pathway”) [ 22 ], or to exploit suitable chemical tools to specifically address individual domains or even the block junction [ 23 , 24 ] between two adjacent segments in block copolymer nanostructures [ 25 , 26 ].…”