Designing Composite Coatings that Provide a Dual-defense Against Fouling
Abstract
Abstract Inspired by marine organisms that utilize active defense mechanisms to prevent the biofouling of their surfaces, we combine computational modeling and experimental studies to create synthetic, gel-based composite films that provide a Òdual-defenseÓ mechanism against fouling. We propose to exploit the unique properties afforded by embedding rigid posts into thermo-responsive gels. When the gel is heated, it collapses to expose the buried posts, which act as ÒspikesÓ preventing the fouling agents from penetrating the layer. As the system dissipates heat and cools down, the gel expands and this dynamic morphological change could be harnessed to dislodge the adsorbed particles. This two-pronged defense against the settlement of particles can provide a distinct platform for anti-fouling applications. The one year funding will allow us to isolate the parameter range in which the gels provide the optimal Òdual-defenseÓ mechanism. The findings from the computational modeling will help guide the experimental studies that will be performed by Aizenberg. In particular, to test the predictions that emerge from the simulations, Aizenberg has developed a new approach in which gold nanorods (AuNR) are introduced into an LCST gel that encompasses rigid needles or blades. Preliminary experiments have shown that irradiation of this composite system causes the local heating of the rods, which then drive the collapse of the gel and the exposure and bending of the blades. This material provides an ideal system for validating the findings from the simulations and correspondingly, the close coupling between the experimental and computational studies will help optimize the performance of the physical system. Notably, these concepts can be tested with the aid of the Hull BUG, which is an autonomous underwater hull grooming robot specifically designed to prevent the accumulation of marine fouling. Namely, the Hull BUG provides sufficient maneuverability that it can approach the coating and apply the necessary energy input (e.g., local irradiation/illumination) to heat the rods and drive the structural transition of the gel. Hence, we have a distinct means of performing field evaluations on our coatings through collaboration with researchers working with the Hull BUG.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 22, 2016
- Source ID
- N000141512157
Entities
People
- Joanna Aizenberg
Organizations
- Office of Naval Research
- President and Fellows of Harvard College
- United States Navy