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The University of Southern Mississippi

Honors Theses

Theses/Dissertations

2020

Articles 1 - 6 of 6

Full-Text Articles in Engineering

Selfsame Epoxide-Amine Microparticle Systems: Investigation Of Crosslink Density, John J. Peyrefitte May 2020

Selfsame Epoxide-Amine Microparticle Systems: Investigation Of Crosslink Density, John J. Peyrefitte

Honors Theses

Epoxide-amine matrix materials containing microparticles with the same chemical composition provide a model system to study interphase formation in highly crosslinked epoxide-amine matrix materials. The epoxide monomer was varied between three different monomer systems to study the model system’s relationship with crosslink density. The same amine monomer, cure procedure, and stoichiometric ratio of epoxide and amine groups were used to prepare each type of microparticle and matrix material. The differences in the epoxide monomer structure affected the crosslink density of the unmodified matrix material, which was concluded to influence the effect of microparticle presence on crosslink density. For the unmodified …

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Coordinated Autonomy Of Unmanned Aerial Vehicles (Uavs), Paribartan Dhakal May 2020

Coordinated Autonomy Of Unmanned Aerial Vehicles (Uavs), Paribartan Dhakal

Honors Theses

Unmanned Aerial Vehicles (UAVs) are being extensively used in diverse sectors of the society for various tasks ranging from videography to an extremely sensitive situation such as first responders helping during a disaster. It has been seen that if a fleet of UAVs is deployed, they can perform a task quicker and more efficiently than a single UAV. With an increase in the number of UAVs, a problem arises of handling them with proper control structures. It has been studied that the Behavior Trees (BT) can be a better control architecture to handle the autonomous vehicles, as BTs are more …

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Co-Assembly Behavior Of Neutral And Zwitterionic Amphiphilic Block Copolymers In The Fabrication Of Glassy Polymer Vesicles, Elina Ghimire May 2020

Co-Assembly Behavior Of Neutral And Zwitterionic Amphiphilic Block Copolymers In The Fabrication Of Glassy Polymer Vesicles, Elina Ghimire

Honors Theses

Polymersomes, also known as polymer vesicles, are hollow capsules fabricated through the solution assembly of amphiphilic block copolymers. Polymer vesicles have garnered a great deal of interest in materials science because of their potential application in areas such as drug delivery, diagnostics and imaging, gene therapy, and as nanoreactors. The goal of this project is to understand the factors that affect the arrangement of triblocks in vesicle membrane via the study of the co-assembly behavior of linear amphiphilic triblocks with different hydrophilic blocks. We investigated the self- and co-assembly behavior of amphiphilic triblock copolymers with neutral hydrophilic blocks. Moreover, we …

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Investigating The Effect Of Hydrophilic Block Length On The Co-Assembly Behavior Of Amphiphilic Triblock Copolymers, Alexandra M. Garrett May 2020

Investigating The Effect Of Hydrophilic Block Length On The Co-Assembly Behavior Of Amphiphilic Triblock Copolymers, Alexandra M. Garrett

Honors Theses

Polymer vesicles and micelles have been of interest in the scientific community for the past few decades due to potential biomedical applications in areas such as drug delivery, nanoreactors, and biosensing. Polymer vesicles and micelles are formed through the self-assembly of amphiphilic block copolymers. The objective of this project is to gain a better understanding of the influence of hydrophilic block copolymer length and composition in controlling the resulting morphologies from the co-assembly of triblock copolymers. First, a hydrophobic block composed of poly(methyl acrylate) was synthesized using reversible addition-fragmentation chain-transfer (RAFT) polymerization mediated by a difunctional chain-transfer agent. The block …

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Thiol-Induced Degradation Of Hydrogels Utilizing Multiresponsive Dithiomaleimides Crosslinkers, Kundu Thapa May 2020

Thiol-Induced Degradation Of Hydrogels Utilizing Multiresponsive Dithiomaleimides Crosslinkers, Kundu Thapa

Honors Theses

Hydrogels are hydrophilic, three-dimensional materials used as platforms for various biomedical applications such as drug delivery, biosensors, or as scaffolds in tissue engineering. The ability to degrade on demand in response to biological cues is particularly attractive whether dealing with microgels or if one aims to release an active ingredient from a scaffolding material. For instance, many cancer-remediation drug delivery platforms leverage the high concentration of glutathione, a thiol-containing tripeptide, found in cancerous cells. In this work, poly(ethylene glycol) acrylate hydrogels were fabricated using dithiomaleimide (DTM) moieties. DTMs are known to undergo thiol-exchange reactions favoring the dissolution of the hydrogel …

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Tailoring Photodegradation Rates Of Acetal-Containing Polymer Networks, Michael Sandoz May 2020

Tailoring Photodegradation Rates Of Acetal-Containing Polymer Networks, Michael Sandoz

Honors Theses

In this thesis, we explore the degradation of poly (thioether acetal) thermosets via a photoinduced thiol-catalyzed ß-scission of acetal linkages incorporated as network crosslink junctions. Specifically, a library of bis-allyl acetal-containing monomers derived from para-substituted benzaldehydes was synthesized and formulated into photopolymerizable thiol-ene resins with commercially available thiol monomers. By varying the electron donating or withdrawing nature of the monomer substituent, we explored the impact of substituent effects on the rate of polymer degradation. Furthermore, we compare the results to those expected from a classical Hammett-type relationship of substituent electronic effects. FTIR was employed to track the appearance of the …

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