Antifouling and Fouling-Release Mechanisms of New Zwitterionic Polymers and Amphiphilic Polymers
Abstract
Marine organisms such as barnacles, mussels, and seaweeds can grow on ocean-going ships, leading to biofouling. Marine biofouling causes reduced speed and extra fuel use for the naval ships, and excessive financial burden for the US Navy. The current ship antifouling coatings contain toxic components, negatively impacting the marine environment. To reduce, minimize, and prevent marine biofouling, and mitigate the environmental impact of ship coatings, extensive research has been carried out to design and develop benign polymer materials for marine coating applications. However, marine environment is very complicated, and marine biofouling can occur by many different marine organisms under vast different conditions. The objective of this proposed research is to understand molecular mechanisms of marine biofouling and antifouling/fouling-release activities of new zwitterionic (ZW) polymers and new amphiphilic materials, providing important knowledge for the design and development of nontoxic antifouling/fouling-release polymer coatings with improved performance. Sum frequency generation (SFG) vibrational spectroscopy, a sub-monolayer surface/interface sensitive nonlinear optical spectroscopic technique, will be the main experimental tool applied in this research, supplemented by computer simulations. A variety of new zwitterionic and amphiphilic polymer materials will be included in this study, including zwitterionic polymers with different degrees of charge delocalization, fluorinated zwitterionic polymers, new amphiphilic copolymers, and polymers with amphiphilic additives. SFG will be applied to probe molecular structures and molecular interactions at buried solid/liquid interfaces in situ in real time. Such results will be correlated to those obtained using computer simulations to reveal detailed relationships among polymer composition, interfacial polymer structure and restructuring dynamics, surface hydration, salt effects on surface hydration, protein interaction, and barnacle attachment of these materials. The SFG and computer simulation results will also be correlated to those acquired from field tests regarding antifouling and fouling-release properties of these new polymer materials. This highly interdisciplinary research will be performed in collaboration with many researchers supported by the ONR Environmental Quality Program. The results obtained from this research will provide in-depth understanding on the effects of charge delocalization and fluorinated group incorporation on interfacial polymer structure and restructuring dynamics, surface hydration, salt effects, and interfacial interactions with biological systems of ZW polymer materials. This research will also elucidate how different hydrophobic and hydrophilic compositions in the new amphiphilic materials influence the interfacial polymer and water behavior, salt effect on surface hydration, and interfacial protein/barnacle interactions. Detailed barnacle peptide conformation and orientation on various zwitterionic and amphiphilic polymers will be determined and compared using a combined study with SFG experiments, structure prediction from sequence software, computer simulation, and Hamiltonian SFG spectra calculation. The knowledge obtained from this study will provide important guidance for design and development of antifouling and fouling-release coatings used in the marine environment with improved performance, which has great future naval relevance. Approved for Public Release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2023
- Source ID
- N000142312127
Entities
People
- Zhan Chen
Organizations
- Board of Regents of the University of Michigan
- Office of Naval Research
- United States Navy