Marine biofouling has troubled mankind, both environmentally and economically, since they set sail, resulting in many undesired consequences such as increased drag, reduced maneuverability, increased fuel consumption and greenhouse gas emissions, and heightened maintenance costs. This problem is highly complex as it involves more than 4000 marine organisms with varying modes of adhesion and surface preferences as well as many aquatic environments. The common state-of-the-art approaches to contend with marine biofouling on the submerged surfaces of ships in seawater has antifouling (AF) and fouling-release (FR) surfaces. As AF coating systems utilize biocides which are often toxic to the environment to prevent settlement of biofoulants, the endeavors have been shifted towards non-toxic FR marine system. Many FR systems take advantage of low surface energy and modulus polydimethylsiloxane (PDMS) on their surface, while the recent attempts explored the simultaneous effect of PDMS and hydrophilic moieties (i.e. polyethylene glycol (PEG) or zwitterionic polymers) on an FR surface, known as amphiphilic surfaces. Thus, the work in this dissertation focused on attaining amphiphilic surfaces with desirable FR performance. The studies in this dissertation were investigated to deliver two goals: 1) Enhancing the (FR) fouling-release performance of previously developed coating systems; 2) Introducing novel fouling-release marine coatings with set criteria. To address the former, a series of amphiphilic additives containing PDMS and hydrophilic polymers (zwitterionic-based or PEG) were prepared in chapters two-five. These additives were incorporated in several previously developed FR coating systems in order to modify their surfaces and enhance their FR performance. To address the latter, two amphiphilic marine coating systems were explored for accessing durable, non-toxic, and effective FR surfaces using epoxy-amine crosslinking chemistry. Overall, the studies in this dissertation not only demonstrated viable FR surfaces with desirable performance against several representative marine organisms such as N. incerta, U. linza, C. lytica, barnacles, and mussels but also contributed a deeper understanding about the effect of amphiphilicity concentration/balance on surface and FR properties.

Barnacles are dominant hard–fouling organisms in marine waters. They attach to substrates by secreting a complex proteinaceous adhesive. Understanding the chemical composition of this multi–protein underwater adhesive and how it is affected by environmental variables, such as oceanic temperatures, is critical for developing nontoxic solutions to control biofouling. Previous experiments in our lab revealed an inverse relationship between critical removal stress (CRS) and temperatures at which barnacles were reared. Further investigations showed that this correlation is not attributed to differences in physical properties such as barnacle size or short–term changes in the viscosity of adhesive. Therefore, the observed effects may be influenced by a physiological response to temperature during initial growth and development. We hypothesized that rearing temperature affects the expression of proteins found in the adhesive matrix. To elucidate the underlying mechanisms responsible for the temperature effect, we analyzed uncured barnacle adhesive using two-dimensional gel electrophoresis (2DGE) and matrix-assisted laser desorption/ionization-tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry (MS). In our analysis, we 1) detected differences in protein expression at two experimental temperatures (15°C and 25°C) and 2) identified several proteins that may serve functional roles in the process of adhesion. Our data are also consistent with a model that the curing process of barnacle adhesive may be analogous to the process of wound healing in animals.