Publication Date
2019
Document Type
Dissertation/Thesis
First Advisor
Sinko, Robert
Degree Name
M.S. (Master of Science)
Legacy Department
Department of Mechanical Engineering
Abstract
Cellulose nanocrystals (CNCs) are a distinctive nanomaterial derived from cellulose, the most abundant natural polymer on Earth, and the primary reinforcing structural component of cellulose fibrils found within the plant cell wall. These nanocrystals exhibit mechanical properties comparable to synthetic aramid fibers but are advantageous as they are biodegradable, renewable, and can be produced sustainably as they are predominantly extracted from naturally occurring cellulosic materials. These qualities make it a sustainable, highly renewable and environmentally friendly material to be used in place of synthetic materials in a variety of applications. With their high surface area to volume ratio, low level of defect, impressive mechanical stiffness and potentiality for engineered surface chemistries, CNCs have been exploited to develop cheaper, renewable nanocomposite materials with unique capabilities. In these nanocomposites, CNCs serve as the reinforcing filler phase within a synthetic polymer matrix such as acrylic glasses or polystyrene foams. While nanocomposites have been fabricated with CNCs as the reinforcing phase, a number of challenges have presented themselves including poor dispersion of CNCs and degradation of mechanical properties upon exposure to moisture. One method to address these shortcomings is surface modification of CNCs to inhibit their hydrophilic nature via direct grafting of synthetic polymer chains in an effort to create high-performance nanocomposites while maintaining moisture-resilient mechanical properties. In this work, the effect of polymer grafting on individual CNCs is investigated using fully atomistic molecular simulation. Using grand canonical Monte Carlo (GCMC) simulations, the effect of polymer grafts on moisture adsorption is explored to determine how grafting parameters such as polymer chain length, grafting density, and polymer species impact the adsorption characteristics of CNCs.
Recommended Citation
Breen-Lyles, Mary Elizabeth, "Direct Polymer Grafting as a Method of Maintaining the Mechanical Properties of Cellulose Nanocrystals in the Presence of Moisture" (2019). Graduate Research Theses & Dissertations. 6881.
https://huskiecommons.lib.niu.edu/allgraduate-thesesdissertations/6881
Extent
66 pages
Language
eng
Publisher
Northern Illinois University
Rights Statement
In Copyright
Rights Statement 2
NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.
Media Type
Text
Included in
Materials Science and Engineering Commons, Mechanical Engineering Commons, Other Physics Commons