Adaptive Omniphobic Surfaces for Flow and Fouling Control
Abstract
Marine fouling is a challenging problem to mitigate, not only due to its severe impact, but also due to the significant diversity in the kinds of foulants, and their underlying adhesion mechanisms. Marine foulants cover a broad range of mechanical properties and length scales: from soft foulants such as bacterial biofilms and algae to hard foulants such as mollusks, crustaceans, or ice. Their accretion on naval assets compromises the surfaces exposed to seawater by increasing hydrodynamic drag and noise signature, creates safety hazards due to corrosion, and can even cause complete loss of surface functionality. These fouling problems raise the costs of fueling and maintaining naval assets, cut short their operational lifetime, and limit the zones of operability due to the produced noise. While many antifouling solutions have been proposed over the last seven decades, most typically address one particular type of foulants, and often succeed only under limited laboratory conditions. In this proposal, we aim to develop adaptive omniphobic surfaces that can adapt to changing marine environments, and provide robust, broad-spectrum, and durable antifouling and drag reductionperformance. Our technical approach is founded in the integration of chemical and physical synergistic phenomena driving anti-biofouling performance in marine environments, and in the design of adaptive mechanisms that can reinforce this behavior in dynamic environmental conditions. This will be achieved through the design of omniphobic coatings with crosslinked silicone oils both with and without natural marine antimicrobial molecules that we have previously identified (Thrust I). We will also evaluate the performance of the developed surfaces after severe mechanical and chemical weathering, under high water flow rates (up to 10 m/s), and utilize systematic material design to enhance coating durability and weatherability. Dissipative and self-repair strategies (including self-healing dynamic chemistries) will be used to improve the durability and resiliency of the developed coatings even further for long-term adaptive operation in marine environments, beyond current state-of-the-art limitations. We will also utilize pH responsive materials that reinforce antimicrobial activity when subjected to biofilm acidification to provide additional resiliency (Thrust II). The developed surfaces will be tested and optimized against a wide range of hard- and soft-foulants. We will also evaluate the performance of our developed coatings under a wide variety of flow conditions by working with the Navy#s independent validation and verification (IV&V) partner. These efforts will converge toward the development of adaptive, resilient, bilayer composite surfaces for integrated antifouling, drag reduction and noise control multifunctionality (Thrust III). This proposal leverages the recent breakthroughs made by the proposing team on the development of broad-spectrum durable antifouling coatings (Tuteja, Mehta, Webster), extremely durable yet compliant laminate composites (Tuteja,) self-healing and adaptive coatings (Pena-Francesh, Shtein), and world-leading capabilities for biofouling testing (Webster, Mehta). All of the materials developed in this work are non-toxic, non-fluorinated, in many cases derived from the marine environment, and all expected to be environmentally friendly.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 13, 2025
- Source ID
- N000142512133
Entities
People
- Anish Tuteja
Organizations
- Board of Regents of the University of Michigan
- Office of Naval Research
- United States Navy