Date of Award
Master of Science (MS)
Civil, Environmental & Architectural Engineering
Wil V. Srubar III
Mija H. Hubler
This study concerns the development of gelatin-based resins with improved moisture resistance and the integration of the developed resins into biobased composites for construction applications. In the U.S., 96 million tons of construction and demolition waste are landfilled each year [U.S. EPA 2009]. Therefore, there is a need for biobased construction materials that reduce reliance on non-renewable petroleum resources and biodegrade in landfills at the end of their intended service life. In this work, gelatin resins were prepared with varying concentrations of gelatin to water ratios (g/w), and 40% g/w resins were selected for techniques to improve moisture resistance by adding varying amounts of terephthalaldehye (TPA) and wine tannin (T). The gelatin concentration of 40% g/w was selected because it demonstrated good mechanical properties, high bonding strength, and reduced moisture absorption when compared to 10%, 20%, and 30% g/w resins. The effect of concentration on the tensile mechanical properties and additives (e.g., TPA and T) on the moisture absorption properties of the gelatin based resins was investigated. Also in this work, the developed gelatin resins were used to produce two biobased composites: (1) a gelatin fiber reinforced polymer (FRP) composite and (2) a gelatin wood veneer (GWV) composite. The tensile mechanical properties and fracture surface morphology of the fully biobased gelatin-flax FRP composite were characterized and compared to FRP composites with partially biobased (e.g. gelatin-fiberglass and epoxy-flax) and fully synthetic (e.g. epoxy-fiberglass) constituents. The flexure properties of GWV composites made using gelatin resins with and without additives were investigated in ambient, low, and high humidity conditions over time. The results from this study indicate that the tensile strength and modulus of gelatin resins exceed ACI 440.8-13 minimum requirements, and 40% g/w resin with 10% T to gelatin by weight exhibited the greatest improved moisture resistance. The data also indicate that fully biobased gelatin-flax composites exhibit similar mechanical properties compared to fully synthetic epoxy-fiberglass composites. Finally, the results show that the GWV composites maintain flexural properties in low humidity conditions after 14 days and lose flexural properties in high humidity conditions after 1 day. Based on this study, biobased gelatin resins and composites demonstrate a marked potential to be used as alternative materials in the construction industry, especially in temporary structural applications.
Hess, Kristen, "Mechanical and Moisture Absorption Properties of Biobased Gelatin Films and Composites for Construction Applications" (2015). Civil Engineering Graduate Theses & Dissertations. 25.