Committee:

Prof. Kyriaki Kalatizidou – MSE/ME (advisor)

Prof. Tequila A. L. Harris – ME (advisor)

Prof. Karl Jacob – MSE (advisor)

Prof. Robert J. Moon – RBI

Prof. Meisha Shofner – MSE

Abstract

Glass fiber reinforced composites (GFRCs) are versatile materials with a broad range of applications in the transportation industry. Their widespread use, especially in the automotive sector, has motivated research on improving their mechanical performance while reducing their weight to boost vehicle fuel efficiency. Depositing cellulose nanocrystals (CNC) onto glass fiber (GF) surfaces to enhance the fiber matrix interactions provides a potential avenue for increasing the composite strength and lightweighting. However, the technology available for coating CNCs onto packed GF media such as rovings and fabrics has struggled with scalability, coating homogeneity, and fluid penetration.  

This work investigates the efficacy of vacuum-assisted slot die coating as a scalable method for depositing CNC coatings onto each fiber within a GF fabric, with the end goal of high-volume CNC-GFRC production. To accomplish these goals, the first task is focused on understanding how the processing conditions of slot die coating CNC affects the coating quality on GF fabric. The mechanics of the slot die coating process will also be explored through analytical and computational models. The coating characterization is conducted using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Fourier Transform Infrared Spectroscopy (FTIR). The second task is dedicated to understanding how the CNC coating and its quality affect the mechanical properties of GFRCs. For this task, GFRCs are manufactured using CNC coated GF fabrics, and their mechanical properties are measured. Lastly, the third task explores the potential of lightweighting of GFRCs using CNC through predictive micromechanical models and GF content reduction. This study, if successful, will not only enable a greater understanding of the mechanics of slot die coating GF fabrics, but also provide the technology for manufacturing improved GFRCs, and a new high-volume application for CNCs.