{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/71847"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/71847","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Deformation and Transformation Mechanisms of Polybutene and Poly(vinylidene Fluoride)","abstract":"The deformation of thin films of polybutene (PB) and poly(vinylidene fluoride) (PVF$\\sb2$) occurs by micronecking. Finite blocks are drawn off the edge of the microneck depending upon the orientation of the original crystalline lamellae comprising the spherulites with respect to the draw direction. Deformation of fresh PB thin film is accompanied by a transformation of tetragonal form to hexagonal form. Potassium permanganate etching and dark field microscopy of fresh thick and thin films reveal that the lateral crystal size of the tetragonal form crystals in the fresh film is significantly reduced upon transformation to the hexagonal crystals during aging. Dark field microscopy and electron diffraction patterns of the deformed PB thin films indicate that the majority of tetragonal crystalline segments transformed into the stable hexagonal crystals while still incorporated in the original lamellae, i.e. during tilt and slip of molecules within the blocks. Morphology of deformed thick films indicates the deformation behavior of thick films is more coherent than that of thin films.","abstract_html":"The deformation of thin films of polybutene (PB) and poly(vinylidene fluoride) (PVF$\\sb2$) occurs by micronecking. Finite blocks are drawn off the edge of the microneck depending upon the orientation of the original crystalline lamellae comprising the spherulites with respect to the draw direction. Deformation of fresh PB thin film is accompanied by a transformation of tetragonal form to hexagonal form. Potassium permanganate etching and dark field microscopy of fresh thick and thin films reveal that the lateral crystal size of the tetragonal form crystals in the fresh film is significantly reduced upon transformation to the hexagonal crystals during aging. Dark field microscopy and electron diffraction patterns of the deformed PB thin films indicate that the majority of tetragonal crystalline segments transformed into the stable hexagonal crystals while still incorporated in the original lamellae, i.e. during tilt and slip of molecules within the blocks. Morphology of deformed thick films indicates the deformation behavior of thick films is more coherent than that of thin films.","abstract_has_math":true,"creators":["Hsu, Tsuey-Chen"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Metallurgical Engineering","degree_department":null,"school":null,"contributors":["Geil, Phillip H."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-16T20:52:14Z","date_published":"2014-12-16T20:52:14Z","updated_at":"2026-07-22T22:26:05Z","subjects":["Engineering, Materials Science"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8803070"],"render_values":[{"text":"(UMI)AAI8803070","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/71847","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Geil, Phillip H."]},{"key":"dc:creator","label":"Author","values":["Hsu, Tsuey-Chen"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-16T20:52:14Z","10000-01-01","1987"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Metallurgical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Engineering, Materials Science"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/71847","(UMI)AAI8803070"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The deformation of thin films of polybutene (PB) and poly(vinylidene fluoride) (PVF$\\sb2$) occurs by micronecking. Finite blocks are drawn off the edge of the microneck depending upon the orientation of the original crystalline lamellae comprising the spherulites with respect to the draw direction. Deformation of fresh PB thin film is accompanied by a transformation of tetragonal form to hexagonal form. Potassium permanganate etching and dark field microscopy of fresh thick and thin films reveal that the lateral crystal size of the tetragonal form crystals in the fresh film is significantly reduced upon transformation to the hexagonal crystals during aging. Dark field microscopy and electron diffraction patterns of the deformed PB thin films indicate that the majority of tetragonal crystalline segments transformed into the stable hexagonal crystals while still incorporated in the original lamellae, i.e. during tilt and slip of molecules within the blocks. Morphology of deformed thick films indicates the deformation behavior of thick films is more coherent than that of thin films.","Similar studies of the deformation of PVF$\\sb2$, which is accompanied by a phase transformation of anti-polar $\\alpha$-phase to the polar $\\beta$-phase are also described. In contrast to the transformation behavior of PB thin film, in PVF$\\sb2$, based on the bright field microscopy and electron diffraction patterns of deformed PVF$\\sb2$ thin films, the transformation appears to occur only during or after the molecules are stripped off the blocks and fibrils are formed. Wide angle and small angle x-ray diffraction patterns indicate that the transformation from $\\alpha$ to $\\beta$ phase in the deformed thick films is strongly dependent on the temperature at which the deformation occurs. At natural draw ratio (ca. 300%) transformation is more complete in the cold drawn (82$\\sp\\circ$C) samples than in the hot drawn (130$\\sp\\circ$C) samples; $\\alpha$-phase crystals tend to be oriented rather than transform into $\\beta$-phase crystals in the hot drawn (130$\\sp\\circ$C) samples.","Made available in DSpace on 2014-12-16T20:52:14Z (GMT). No. of bitstreams: 1 8803070.pdf: 10328554 bytes, checksum: c4b42f5e283510803ec60fe3bde9017b (MD5) Previous issue date: 1987","Embargo set by: Seth Robbins for item 72013 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","214 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1987."]},{"key":"dc:title","label":"Title","values":["Deformation and Transformation Mechanisms of Polybutene and Poly(vinylidene Fluoride)"]}]}],"canonical_facts":{"dc:contributor":["Geil, Phillip H."],"dc:creator":["Hsu, Tsuey-Chen"],"dc:date":["2014-12-16T20:52:14Z","10000-01-01","1987"],"dc:description":["The deformation of thin films of polybutene (PB) and poly(vinylidene fluoride) (PVF$\\sb2$) occurs by micronecking. Finite blocks are drawn off the edge of the microneck depending upon the orientation of the original crystalline lamellae comprising the spherulites with respect to the draw direction. Deformation of fresh PB thin film is accompanied by a transformation of tetragonal form to hexagonal form. Potassium permanganate etching and dark field microscopy of fresh thick and thin films reveal that the lateral crystal size of the tetragonal form crystals in the fresh film is significantly reduced upon transformation to the hexagonal crystals during aging. Dark field microscopy and electron diffraction patterns of the deformed PB thin films indicate that the majority of tetragonal crystalline segments transformed into the stable hexagonal crystals while still incorporated in the original lamellae, i.e. during tilt and slip of molecules within the blocks. Morphology of deformed thick films indicates the deformation behavior of thick films is more coherent than that of thin films.","Similar studies of the deformation of PVF$\\sb2$, which is accompanied by a phase transformation of anti-polar $\\alpha$-phase to the polar $\\beta$-phase are also described. In contrast to the transformation behavior of PB thin film, in PVF$\\sb2$, based on the bright field microscopy and electron diffraction patterns of deformed PVF$\\sb2$ thin films, the transformation appears to occur only during or after the molecules are stripped off the blocks and fibrils are formed. Wide angle and small angle x-ray diffraction patterns indicate that the transformation from $\\alpha$ to $\\beta$ phase in the deformed thick films is strongly dependent on the temperature at which the deformation occurs. At natural draw ratio (ca. 300%) transformation is more complete in the cold drawn (82$\\sp\\circ$C) samples than in the hot drawn (130$\\sp\\circ$C) samples; $\\alpha$-phase crystals tend to be oriented rather than transform into $\\beta$-phase crystals in the hot drawn (130$\\sp\\circ$C) samples.","Made available in DSpace on 2014-12-16T20:52:14Z (GMT). No. of bitstreams: 1 8803070.pdf: 10328554 bytes, checksum: c4b42f5e283510803ec60fe3bde9017b (MD5) Previous issue date: 1987","Embargo set by: Seth Robbins for item 72013 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","214 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1987."],"dc:identifier":["http://hdl.handle.net/2142/71847","(UMI)AAI8803070"],"dc:subject":["Engineering, Materials Science"],"dc:title":["Deformation and Transformation Mechanisms of Polybutene and Poly(vinylidene Fluoride)"],"dc:type":["text"],"thesis:degree_discipline":["Metallurgical Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:05Z"}