Effects of chemical functionalization methods and geometrical configurations of carbon nanotubes on mechanical and thermal properties of polymeric nanocomposites
Abstract
Polymeric nanocomposites have attracted considerable interest, compared to traditional
polymeric composites, because of their substantially improved mechanical, thermal, electrical,
and magnetic properties, while maintaining their light-weight advantage. One of the most widely
investigated and researched types of nanocomposites is carbon nanotube (CNT) reinforced
polymeric resins, because of their promising property improvements, enhanced performance, and
multifunctionality, which make them very attractive for high-performance structural
applications. Carbon nanotubes can be synthesized in various geometrical shapes and
configurations with different structural characteristics and material properties. Some of the main
challenges for the effective incorporation of CNTs in polymeric resins are their agglomeration,
non-uniform dispersion, and poor bonding/interface with the molecules of host polymeric resins.
Several solutions have been proposed and applied to CNTs to overcome these challenges, but not
all of them were fully successful. One of the most effective methods is to change the structure of
the side walls of carbon nanotubes by means of chemical functionalization using strong acids.
The main objectives of this research are to study the effects of various chemical
functionalization methods, structural geometries of CNTs, and weight percentages (wt%) on the
mechanical and thermal properties of CNTs reinforced polymeric nanocomposites. Two
geometrical configurations of CNTs (e.g., straight and helical) were functionalized using
different chemical functionalization methods. Then, different weight percentages of the
functionalized CNTs were mixed within a polymeric resin system and used to fabricate
nanocomposite specimens for further characterization and testing. All testing procedures
followed the American Society for Testing and Materials (ASTM) standards.
Description
Thesis (Ph.D.)-- Wichita State University, College of Engineering, Dept. of Mechanical Engineering