Studies of free radicals in the physics, chemistry, biology, and materials science have contributed to advancements in those fields. The presence of radicals can damage the material and system in some instances and, in some cases, they may enhance the property of the material as well. Knowledge of free radical transformations helps in resilience of certain polymers and inhibition of the oxidation of food and medicine. In this thesis, using the magnetic resonance techniques, EPR and NMR, the generation of free radicals and their effect on the structure of the material is being studied.
Kapton Polyimide (PI, Kapton®) used in space missions as a thermal management blanketing material makes it vulnerable to the ionic, proton and electronic radiations when exposed to outer space environment. Modification of PI’s chemical structure occurs and therefore have a dramatic impact on the electronic conductive behavior. The recovery mechanism (free radical evolution) of PI in vacuum and air after having been subjected to 90 KeV electron irradiation is studied in this research.
Melanin, a biopolymer formed by polymerization of quinone radicals, is intriguing study among scientists because of their unique structural and optoelectronic properties. To tune this polymer for various applications melanin -like tripeptides are synthesized and properties of those peptides based on free radical polymerization are studied. Finally, enhancement in conductivity of PEDOT: PSS electrodes used in opto-electronic devices is being studied by probing the behavior of the charge carriers, especially polarons under the effect of magnetophoresis.
","abstract_html":"<p>Studies of free radicals in the physics, chemistry, biology, and materials science have contributed to advancements in those fields. The presence of radicals can damage the material and system in some instances and, in some cases, they may enhance the property of the material as well. Knowledge of free radical transformations helps in resilience of certain polymers and inhibition of the oxidation of food and medicine. In this thesis, using the magnetic resonance techniques, EPR and NMR, the generation of free radicals and their effect on the structure of the material is being studied.</p> <p>Kapton Polyimide (PI, Kapton®) used in space missions as a thermal management blanketing material makes it vulnerable to the ionic, proton and electronic radiations when exposed to outer space environment. Modification of PI’s chemical structure occurs and therefore have a dramatic impact on the electronic conductive behavior. The recovery mechanism (free radical evolution) of PI in vacuum and air after having been subjected to 90 KeV electron irradiation is studied in this research.</p> <p>Melanin, a biopolymer formed by polymerization of quinone radicals, is intriguing study among scientists because of their unique structural and optoelectronic properties. To tune this polymer for various applications melanin -like tripeptides are synthesized and properties of those peptides based on free radical polymerization are studied. Finally, enhancement in conductivity of PEDOT: PSS electrodes used in opto-electronic devices is being studied by probing the behavior of the charge carriers, especially polarons under the effect of magnetophoresis.</p>","abstract_has_math":false,"creators":["Humagain, Sunita"],"institution":"The Graduate School and University Center of The City University of New York","degree_name":"Doctor of Philosophy","degree_level":"Doctoral","degree_discipline":"Physics","degree_department":null,"school":null,"contributors":[],"advisors":["Steve G. Greenbaum"],"committee_chairs":[],"committee_members":["Ryann C. Hoffmann","Hyungsik Lim","Yuhang Ren","Sophia N. Suarez"],"year":2019,"date_issued":"2019-02-01T08:00:00Z","date_published":"2019-02-01T08:00:00Z","updated_at":"2026-07-24T01:59:30Z","subjects":["Biological and Chemical Physics","Polyimide","Free Radicals","Material Chemistry","Electron Paramagnetic Resonance","Nuclear Magnetic Resonance"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://academicworks.cuny.edu/gc_etds/2981","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Steve G. Greenbaum"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Ryann C. Hoffmann","Hyungsik Lim","Yuhang Ren","Sophia N. Suarez"]},{"key":"dc:creator","label":"Author","values":["Humagain, Sunita"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2019-01-22T08:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Physics"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Doctoral"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["The Graduate School and University Center of The City University of New York"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biological and Chemical Physics","Polyimide","Free Radicals","Material Chemistry","Electron Paramagnetic Resonance","Nuclear Magnetic Resonance"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://academicworks.cuny.edu/gc_etds/2981"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Studies of free radicals in the physics, chemistry, biology, and materials science have contributed to advancements in those fields. The presence of radicals can damage the material and system in some instances and, in some cases, they may enhance the property of the material as well. Knowledge of free radical transformations helps in resilience of certain polymers and inhibition of the oxidation of food and medicine. In this thesis, using the magnetic resonance techniques, EPR and NMR, the generation of free radicals and their effect on the structure of the material is being studied.
Kapton Polyimide (PI, Kapton®) used in space missions as a thermal management blanketing material makes it vulnerable to the ionic, proton and electronic radiations when exposed to outer space environment. Modification of PI’s chemical structure occurs and therefore have a dramatic impact on the electronic conductive behavior. The recovery mechanism (free radical evolution) of PI in vacuum and air after having been subjected to 90 KeV electron irradiation is studied in this research.
Melanin, a biopolymer formed by polymerization of quinone radicals, is intriguing study among scientists because of their unique structural and optoelectronic properties. To tune this polymer for various applications melanin -like tripeptides are synthesized and properties of those peptides based on free radical polymerization are studied. Finally, enhancement in conductivity of PEDOT: PSS electrodes used in opto-electronic devices is being studied by probing the behavior of the charge carriers, especially polarons under the effect of magnetophoresis.
"]},{"key":"dc:title","label":"Title","values":["Magnetic Resonance Studies of Free Radicals Generation and their Impact in Different Polymers"]}]}],"canonical_facts":{"dc:contributor.advisor":["Steve G. Greenbaum"],"dc:contributor.committeemember":["Ryann C. Hoffmann","Hyungsik Lim","Yuhang Ren","Sophia N. Suarez"],"dc:creator":["Humagain, Sunita"],"dc:date.available":["2019-01-22T08:00:00Z"],"dc:description.abstract":["Studies of free radicals in the physics, chemistry, biology, and materials science have contributed to advancements in those fields. The presence of radicals can damage the material and system in some instances and, in some cases, they may enhance the property of the material as well. Knowledge of free radical transformations helps in resilience of certain polymers and inhibition of the oxidation of food and medicine. In this thesis, using the magnetic resonance techniques, EPR and NMR, the generation of free radicals and their effect on the structure of the material is being studied.
Kapton Polyimide (PI, Kapton®) used in space missions as a thermal management blanketing material makes it vulnerable to the ionic, proton and electronic radiations when exposed to outer space environment. Modification of PI’s chemical structure occurs and therefore have a dramatic impact on the electronic conductive behavior. The recovery mechanism (free radical evolution) of PI in vacuum and air after having been subjected to 90 KeV electron irradiation is studied in this research.
Melanin, a biopolymer formed by polymerization of quinone radicals, is intriguing study among scientists because of their unique structural and optoelectronic properties. To tune this polymer for various applications melanin -like tripeptides are synthesized and properties of those peptides based on free radical polymerization are studied. Finally, enhancement in conductivity of PEDOT: PSS electrodes used in opto-electronic devices is being studied by probing the behavior of the charge carriers, especially polarons under the effect of magnetophoresis.
"],"dc:identifier":["https://academicworks.cuny.edu/gc_etds/2981"],"dc:subject":["Biological and Chemical Physics","Polyimide","Free Radicals","Material Chemistry","Electron Paramagnetic Resonance","Nuclear Magnetic Resonance"],"dc:title":["Magnetic Resonance Studies of Free Radicals Generation and their Impact in Different Polymers"],"thesis:degree_discipline":["Physics"],"thesis:degree_level":["Doctoral"],"thesis:degree_name":["Doctor of Philosophy"],"thesis:institution_name":["The Graduate School and University Center of The City University of New York"]},"updated_at":"2026-07-24T01:59:30Z"}