Impact-Resistant Soft Materials Engineered by Hierarchical Noncovalent Energy Dissipation
Abstract
State-of-the-art impact-resistant materials such as Kevlar resist impact but lack flexibility due to their crystalline structures. To address this limitation, soft polymer networks that stiffen upon impact have been explored. However, the mechanical performance of traditional polymer materials is limited because they are homogeneous when viewed on the macroscale. In contrast, natural organisms utilize structural features at various length scales to dynamically resist force- for example, the skin of sea cucumbers stiffens due to the collective activation of multiple transient interactions between protein fibers, and horse hooves employ gradients of dry and wet keratin to distribute forces generated during galloping. Designing soft materials with similar structural control over multiple length scales is a grand challenge. Here we propose to develop a synthetic platform to program the structure of fibrous materials over multiple length scales, thereby realizing novel impact-resistant soft materials. Our approach exploits the specific hydrogen-bond pairing interactions of biotic and abiotic nucleobases to generate nonsymmetric macrocycles that can assemble into supramolecular fibers. We will define the spatial arrangement and identity of functional groups on the periphery of these macrocycles, thereby programming how they and their fibers interact. Crucially, through organic synthesis, we will modify these natural nucleobase motifs to control the strength and lifetime of inter-fiber interactions. By modulating the relative strengths and positions of multiple, transiently interacting domains, these materials will be endowed with mechanisms for hierarchical energy dissipation, which we expect will permit nonlinear responses to acute mechanical force and resistance to impact. Successful completion of the proposed work will generate substantial new fundamental knowledge that will accelerate the discovery of novel architectures with attractive mechanical properties and develop the first examples of soft materials with impact-resistant capabilities, with direct relevance to the AF and across the DoD.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2025
- Source ID
- FA95502410104
Entities
People
- Benjamin E. Partridge
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Rochester