“Retrogressive Approach to Determine Fungal Biodegradation Response and Mechanisms to Polyurethane-Based Coatings” by Dr. Justin Biffinger (SERDP Project WP19-1381)
Polymer coating degradation processes (environmental and biological) depend highly on the polymer formulation and its physical properties. However, understanding a microorganism’s mechanism of degrading synthetic and natural protective coatings might allow universal control of these degradation processes and reduce reliance on toxic and environmentally unfriendly additives to solve this persistent problem for DoD weapon systems. In this project, we analyze the degradation of specific polyester and polyether polyurethane coatings using biofilms of one or mixtures of two environmental bacteria and fungi isolated and identified from inside U.S. Air Force aircraft. Our data demonstrate the complex interactions between the polymer and these strains starting from the single cell scale to the formation of biofilms at high relative humidity. This presentation details our approach to correlate the entire polymer coating biodegradation process as a life cycle to simplify the multivariate data sets and trends observed in the program.
“Demonstration of Mold and Mildew Preventative Epoxy Coatings for Naval Ship Interior Coatings” by Dr. Charles White (ESTCP Project WP21-5033)
Operational conditions of Navy surface ships can lead to high risk of fungal growth on surfaces. This is a potential health stressor for the ship’s force and causes unaesthetic conditions for paint and coatings. Additionally, fungal growth has been shown to feed on resins, fillers, and plasticizers found in coatings, leading to corrosion and degraded coating performance over time. This project studies common molds found on Navy ships, determines the effects of mold growth on protective coatings,
and tests potential remediation options. Ship inspections were performed to determine the extent of mold issues across the Navy. In this effort, 27 surface ships were inspected across seven naval locations (Newport News, Virginia; Norfolk, Virginia; Mayport, Florida; San Diego, California, Puget Sound/Everett, Washington; Pearl Harbor, Hawaii; and Yokosuka, Japan). Mold samples were taken from each of these spaces for laboratory analysis. The ship inspections determined the most common ship spaces for mold growth, recorded environmental contributors to growth, and non-destructively tested coating characteristics of mold-affected and clean ship areas. This presentation will focus on illustrating the results of ship inspections performed and will explore the initial results of laboratory DNA analysis of fungal samples taken during the ship survey.
Dr. Justin Biffinger is an assistant professor in the Chemistry Department at the University of Dayton. He has as 20 years of experience in fundamental and applied research in bioenergy and polymer biodegradation mechanisms. Prior to his appointment at the University of Dayton, he was a Research Chemist at Naval Research Laboratory (Washington, D.C.) for nine years in the bioenergy and biofabrication section. While there, he worked on or led several programs in harvesting energy and materials from the environment using bacteria and fungi. After graduate school, he served as a National Research Council postdoctoral associate at the Naval Research Laboratory in Washington, D.C. He has authored or co-authored over 50 peer-reviewed manuscripts in chemistry and applied microbiology. Dr. Biffinger earned a bachelor’s degree in biochemistry from Ithaca College, a master’s degree in chemistry from Bucknell University, and a doctoral degree in chemistry from the University of Nebraska–Lincoln.
Dr. Charles White is the Senior Coating and Corrosion Technical Advisor at the Corrosion and Coatings Engineering and Sustainment Branch at the Naval Surface Warfare Center, Carderock Division in Bethesda, Maryland. Dr. White has been a coating engineer working on coating and corrosion projects for the Navy and U.S. Marine Corps since 2016. He is a CIP Level II certified coating inspector and a lead engineer on the NAVSEA TWH pyramid for corrosion and coating control. Since 2021, Dr. White has been leading a collaborative project on mold inhibitive coatings and fleet surveys to identify and assess the biodiversity of fungal species on U.S. Navy surface ships across various US locations and temperate zones. He has professional experience in applied polymer science, paint and coatings formulation, and paint and coating engineering and application for marine platforms and surface ships. His research interests include functional coatings and stimuli responsive coatings. Dr. White received his bachelor’s degree in polymer science and high performance materials from the University of Southern Mississippi, Hattiesburg, and master’s and doctoral degrees in chemical engineering from Auburn University.