Where Biology and Traditional Polymers Meet: The Potential of Associating Sequence-Defined Polymers for Materials Science

Abstract

Polymers with precisely defined monomeric sequences present an exquisite tool for controlling material properties by harnessing both the robustness of synthetic polymers and the ability to tailor the inter- and intramolecular interactions so crucial to many biological materials. While polymer scientists traditionally synthesized and studied the physics of long molecules best described by their statistical nature, many biological polymers derive their highly tailored functions from precisely controlled sequences. Therefore, significant effort has been applied toward developing new methods of synthesizing, characterizing, and understanding the physics of non-natural sequence-defined polymers. This perspective considers the synergistic advantages that can be achieved via tailoring both precise sequence control and attributes of traditional polymers in a single system. Here, we focus on the potential of sequence-defined polymers in highly associating systems, with a focus on the unique properties, such as enhanced proton conductivity, that can be attained by incorporating sequence. In particular, we examine these materials as key model systems for studying previously unresolvable questions in polymer physics including the role of chain shape near interfaces and how to tailor compatibilization between dissimilar polymer blocks. Finally, we discuss the critical challenges—in particular, truly scalable synthetic approaches, characterization and modeling tools, and robust control and understanding of assembly pathways—that must be overcome for sequence-defined polymers to attain their potential and achieve ubiquity.

Integration of Machine Learning and Coarse-Grained Molecular Simulations for Polymer Materials: Physical Understandings and Molecular Design

“…Finally, while CGMD can capture the geometries of multiple-chain structures, characteristics of bulk material systems remain out of reach. It suggests developing methods to connect chain level properties with bulk assembly behaviors using broader critical parameter spaces such as polydispersity or assembly pathways, etc., to these materials ( DeStefano et al, 2021 ).…”

“…Over the last decade, the development of synthetic polymers focusing on controlling sequence-specific chains has become notable in polymer science and engineering ( Badi and Lutz, 2009 ; Hartmann and Börner, 2009 ; Chan-Seng et al, 2012 ; Lutz et al, 2013 ; Lutz, 2017 ; Guseva et al, 2017 ; Solleder et al, 2017 ; Nanjan and Porel, 2019 ; DeStefano et al, 2021 ). Monomer sequence can dictate important properties of the polymer chains, such as polymer configurations, gyration radius, self-assembly behaviors, etc.…”

“…To answer these questions, it is inevitable to boost our fundamental understandings of sequence-structure-property relationships for polymeric materials with not only a single one, but an assemble of polymer chains. Recently, the computational approach has been an effective alternative tool to enhance our predictive capability due to the limitations of current experimental measurements ( Binder, 1995 ; Li et al, 2012a ; Li et al, 2013 ; Li et al, 2017 ; DeStefano et al, 2021 ). In particular, molecular dynamics (MD) simulation has demonstrated its robustness in capturing physical and mechanical properties of polymers, such as glass transition temperature ( Varnik et al, 2002 ), viscosity ( Mondello and Grest, 1997 ), dynamics and relaxation ( Binder, 1995 ), phase separation ( Tanaka, 1993 ), crystalization ( Kavassalis and Sundararajan, 1993 ; Gee et al, 2006 ), entanglement network ( Everaers et al, 2004 ; Kröger, 2005 ), Young’s modulus and yield strength ( Li and Strachan, 2011 ).…”

Impact of Nanoparticle Size and Surface Chemistry on Peptoid Self-Assembly

“…[24][25][26][27] Peptoids, or poly-N-substituted glycines, are peptide analogs that are functionalized on the nitrogen rather than carbon in the backbone sequence. [28][29][30] Through functionalization of the nitrogen, the monomers can be made soluble in a wide range of solvents, including organics, and the hydrogen-bonding interactions that often dominate secondary structure in peptides are absent. [28][29][30] Without hydrogen bonding, the structure can be tuned by the sequence of the peptoid monomer through side chain/side chain and side chain/backbone interactions.…”

“…[28][29][30] Through functionalization of the nitrogen, the monomers can be made soluble in a wide range of solvents, including organics, and the hydrogen-bonding interactions that often dominate secondary structure in peptides are absent. [28][29][30] Without hydrogen bonding, the structure can be tuned by the sequence of the peptoid monomer through side chain/side chain and side chain/backbone interactions. Peptoids have been shown to self-assemble into a variety of structures, most notably tubes, sheets, and helices.…”