Processing and Characterization of Nanocomposite Fibers and Nanofibers for Structural and Biomedical Applications

<p>In this work, investigations regarding the synthesis and fabrication of novel structural nanocomposite fibers and biocompatible nanofibers were performed. Characterization techniques such as scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) analysis were utilized to analyze the morphological structure of the fibers at the micro and nano-scale. Hybrid nanocomposite fibers from a blend of ultrahigh molecular weight polyethylene (UHMWPE), with Nylon-6 as a secondary polymer phase, combined with single-walled carbon nanotubes (SWCNT) were fabricated using a solution spinning process. Polyethylene-graft-Maleic Anhydride (PE-g-MAH) was used as a compatibilizer to modify the interaction of the immiscible polymer phases. Comparative characterization studies of fibers produced both with and without the inclusion of PE-g-MAH were performed to observe the effect of compatibilization on the morphological development of the fiber microstructure. SEM observations of compatibilized hybrid fibers showed rough and indistinct interfacial separation of the polymer phases. Coating of SWCNTs with polymer phase was observed, which were aligned along the direction of extrusion. DSC results indicated reduction of crystallinity, crystallization rate and lamellar size of the compatibilized blends. Comparative FTIR analysis showed the presence of absorbance peaks related to imide linkages between the UHMWPE backbone and Nylon-6 chains. The DSC and FTIR results indicated the formation of a coupling bond between the polymer phases combined with PE-g-MAH. For fabrication of biocompatible nanofibers as drug delivery systems, electrospinning techniques were utilized to produce neat and drug-loaded nanofibers from biocompatible polymers of cellulose, cellulose Acetate (CA) and poly(ethylene oxide) (PEO). Loading of model anti-cancer drugs, Cisplatin and 5-Fluorouracil into CA and PEO was performed using coaxial electrospinning. Morphological analysis of produced microstructures and fibers were performed using SEM and EDS. Cellulose nanofibers loaded with Cisplatin showed blends of polymer-drug particles attached to the surface of fibers. CA-Cisplatin fibers exhibited drug encapsulation within diverse morphological conformations: straw-sheaf microparticles, dendritic branched nanofibers and swollen fibers with large beads. PEO fibers loaded with Cisplatin and Fluorouracil showed encapsulation of drugs within repeating dumb-bell shaped reservoirs formed along the length of the nanofibers.</p>

Name thesis:degree_name

Master of Science in Applied Engineering (M.S.A.E.)

Level thesis:degree_level

Thesis (restricted to Georgia Southern)

Discipline thesis:degree_discipline

Department of Mechanical Engineering

Year dc:date.available

2015

Author dc:creator

• Absar, Saheem

Contributors dc:contributor

• Gustavo Molina
• Aniruddha Mitra

• ETD
• Fibers
• Nanofibers
• Solution spinning
• Electrospinning
• Nanocomposites
• Characterization
• Biomaterials
• Manufacturing
• Nanoscience and Nanotechnology
• Polymer and Organic Materials

Repository record dc:identifier

https://digitalcommons.georgiasouthern.edu/etd/1234

OAI identifier oai:identifier

oai:digitalcommons.georgiasouthern.edu:etd-2331