{"554331":{"#nid":"554331","#data":{"type":"event","title":"Phd Defense by Amir Bakhtiary Davijani","body":[{"value":"\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003ETHE SCHOOL OF MATERIALS SCIENCE AND ENGINEERING\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003EGEORGIA INSTITUTE OF TECHNOLOGY\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003EUnder the provisions of the regulations for the degree\u003C\/strong\u003E\u003Cbr \/\u003E \u003Cbr \/\u003E \u003Cstrong\u003EDOCTOR OF PHILOSOPHY\u003C\/strong\u003E\u003Cbr \/\u003E \u003Cbr \/\u003E \u003Cstrong\u003Eon Wednesday, August 3, 2016\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003E1:00 PM\u003C\/strong\u003E\u003Cbr \/\u003E \u003Cstrong\u003Ein MRDC 3515\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003Ewill be held the\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003EDISSERTATION DEFENSE\u003C\/strong\u003E\u003Cbr \/\u003E \u003Cbr \/\u003E \u003Cstrong\u003Efor\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003EAmir Bakhtiary Davijani\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003E\u201cEffect of Poly(methyl methacrylate) Wrapping on the Structure and Properties of CNT Films, and Polymer\/CNT Films and Fibers\u201d\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003ECommittee Members:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp align=\u0022center\u0022\u003E\u003Cstrong\u003EProf. Satish Kumar, Advisor, MSE \u003Cbr \/\u003E Prof. Karl Jacob, MSE \u003Cbr \/\u003E Prof. Hamid Garmestani, MSE \u003Cbr \/\u003E Prof. Donggang Yao, MSE \u003Cbr \/\u003E Prof. Seung Woo Lee, ME\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003E\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003ECarbon nanotubes (CNTs) exhibit high electrical and thermal conductivity and good mechanical properties, making them suitable fillers for composites. Their effectiveness as a filler is affected by their state of aggregation. Various solvents, surfactants, and processing techniques have been studied to improve CNT dispersion in polymers. However, prior to this work there is no suitable solution for achieving good CNT dispersion. In this study, a novel process has been developed that prevents CNT aggregation. Ordered helical wrapping of poly (methyl methacrylate) (PMMA) has been achieved on single wall carbon nanotubes (SWNTs). PMMA wrapped SWNT dispersions in dimethylformamide (DMF) are found to be stable for over three months at room temperature. Ordered PMMA wrapping has been confirmed by X-ray diffraction, and the wrapping behavior has also been verified using molecular modeling. PMMA only wraps on SWNTs with diameter of ~1 nm and not on larger diameter CNTs, such as few wall and multi wall carbon nanotubes. PMMA wrapped SWNT dispersions have also been characterized using UV-vis and Raman spectroscopy which confirm exfoliation of PMMA wrapped SWNTs.\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EThe novel finding has been successfully leveraged for electrical energy storage and mechanical reinforcement. SWNT buckypapers, typically have a surface area of about 650 m\u003Csup\u003E2\u003C\/sup\u003E\/g. Using PMMA wrapping, SWNT buckypapers with surface area as high as 950 m\u003Csup\u003E2\u003C\/sup\u003E\/g have been processed. These buckypapers exhibited significantly higher energy storage performance when used as electrodes in electrochemical supercapacitor. At a given power density, the energy density of the high surface electrodes was more than four times higher than the best value reported in the literature to-date for carbon nanotube or graphene electrodes. \u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EWrapping SWNTs with PMMA in buckypaper increased the modulus and tensile strength 5.9 and 3.7 times, respectively, compared to pristine SWNT buckypaper. Stress transfer studies on buckypapers revealed that while non-wrapped SWNTs experienced negligible stress during deformation, PMMA wrapped SWNTs took up to ~1 GPa stress before mechanical failure of the buckypaper. The modulus of composite films with PMMA wrapped SWNTs was 75 % higher than non-wrapped SWNT films. The effect of PMMA wrapping on thermomechanical properties and electrical conductivity of composite films is also reported.\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EPMMA wrapped and non-wrapped SWNTs were incorporated in PAN fibers and the effect of PMMA wrapping on mechanical properties, and stress transfer was characterized. The stress transfer analysis of SWNTs in precursor fiber indicated 45 % higher interfacial shear strength in PMMA wrapped SWNTs compared to non-wrapped SWNTs. PMMA wrapping effectively debundled SWNTs in the PAN fibers as evidenced by Raman spectroscopy of the precursor fiber. SEM images of the carbon fiber fracture surface revealed 60% reduction in fibril size when PMMA wrapped SWNTs were used instead of non-wrapped SWNTs.\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"Effect of Poly(methyl methacrylate) Wrapping on the Structure and Properties of CNT Films, and Polymer\/CNT Films and Fibers"}],"uid":"27707","created_gmt":"2016-07-20 12:18:16","changed_gmt":"2016-10-08 02:18:25","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2016-08-03T14:00:00-04:00","event_time_end":"2016-08-03T16:00:00-04:00","event_time_end_last":"2016-08-03T16:00:00-04:00","gmt_time_start":"2016-08-03 18:00:00","gmt_time_end":"2016-08-03 20:00:00","gmt_time_end_last":"2016-08-03 20:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}