{"62630":{"#nid":"62630","#data":{"type":"event","title":"Ramasubramani Kuduva-Raman-Thanumoorthy - Ph.D. Defense","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ETitle: Constant Temperature Embossing of Supercooled\nPolymer Films\u0026nbsp;\u003C\/strong\u003E\u003C\/p\u003E\n\n\n\n\u003Cp\u003E\u003Cstrong\u003EAbstract\u003C\/strong\u003E\u003C\/p\u003E\n\n\u003Cp\u003EIn this dissertation work, a constant\ntemperature embossing process was developed and investigated. By softening and\ncrystallizing a supercooled polymer at the same temperature, the embossing and\nsolidification stages can be carried out isothermally without thermal cycling.\nThe new process was demonstrated for replicating rectangular trenches with\ndifferent aspect ratio for two different polymers PET and PEEK.The raw\nmaterials were characterized for their thermal and rheological properties to\ndetermine the processing parameters. The polymers were also characterized by a\nmodified tensile testing apparatus to determine the tensile properties of the\nfilm during embossing. The processing parameters including embossing\ntemperature, embossing pressure and embossing time were varied based on the\nmaterial properties and optimized. A semi-empirical model was established to\ncorrelate the crystallizing kinetics of the materials to the change in\nrheological properties during embossing. The model was used as a tool to\npredict the rheological properties of the polymer at conditions where\nexperimental determination is difficult.Finally, embossing simulations with the\nsemi-empirical rheological model were conducted to study the unique process\ndynamics of constant-temperature embossing and verify some experimental\nfindings. Different cases of constant-temperature embossing involving low to\nhigh rates of crystallization were simulated and compared with the conventional\nembossing process. Based on the experimental and simulation results, processing\nstrategies for constant-temperature embossing were devised. \u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003ERamasubramani Kuduva-Raman-Thanumoorthy Ph.D. Defense Presentation\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Ramasubramani Kuduva-Raman-Thanumoorthy Ph.D. Defense Presentation"}],"uid":"27388","created_gmt":"2010-11-09 09:01:27","changed_gmt":"2016-10-08 01:53:24","author":"Bill Miller","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2010-11-22T01:00:00-05:00","event_time_end":"2010-11-22T03:00:00-05:00","event_time_end_last":"2010-11-22T03:00:00-05:00","gmt_time_start":"2010-11-22 06:00:00","gmt_time_end":"2010-11-22 08:00:00","gmt_time_end_last":"2010-11-22 08:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"1238","name":"School of Materials Science and Engineering"}],"categories":[],"keywords":[{"id":"10802","name":"MSE_Interal_Event"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}