ingest cdrApp 2018-06-13T18:44:09.291Z 51cd2fe2-3fd7-401f-a923-a97bc3db68a2 modifyDatastreamByValue RELS-EXT fedoraAdmin 2018-06-13T19:56:43.509Z Setting exclusive relation addDatastream MD_TECHNICAL fedoraAdmin 2018-06-13T19:56:54.922Z Adding technical metadata derived by FITS addDatastream MD_FULL_TEXT fedoraAdmin 2018-06-13T19:57:17.554Z Adding full text metadata extracted by Apache Tika modifyDatastreamByValue RELS-EXT fedoraAdmin 2018-06-13T19:57:39.691Z Setting exclusive relation modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2018-07-11T14:58:49.895Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2018-08-21T19:25:13.318Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2018-09-27T20:12:06.462Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2018-10-12T10:44:35.271Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2018-10-17T16:02:58.036Z modifyDatastreamByValue MD_DESCRIPTIVE cdrApp 2019-03-21T20:58:22.527Z Matthew Everhart Author Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Spring 2018 2018 Materials Science Acoustics Chemistry Attenuation, Composite, Elastomer, Polymer, Soft, Ultrasound eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark Schoenfisch Thesis advisor text Matthew Everhart Author Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Spring 2018 2018 Materials Science Acoustics Chemistry Attenuation, Composite, Elastomer, Polymer, Soft, Ultrasound eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark Schoenfisch Thesis advisor text Matthew Everhart Author Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Spring 2018 2018 Materials Science Acoustics Chemistry Attenuation, Composite, Elastomer, Polymer, Soft, Ultrasound eng Doctor of Philosophy Dissertation Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark H. Schoenfisch Thesis advisor text University of North Carolina at Chapel Hill Degree granting institution Matthew Everhart Creator Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Materials Science Acoustics Chemistry Attenuation; Composite; Elastomer; Polymer; Soft; Ultrasound eng Doctor of Philosophy Dissertation Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark H. Schoenfisch Thesis advisor text University of North Carolina at Chapel Hill Degree granting institution 2018 2018-05 Matthew Everhart Author Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Spring 2018 2018 Materials Science Acoustics Chemistry Attenuation, Composite, Elastomer, Polymer, Soft, Ultrasound eng Doctor of Philosophy Dissertation University of North Carolina at Chapel Hill Graduate School Degree granting institution Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark H. Schoenfisch Thesis advisor text Matthew Everhart Author Department of Chemistry College of Arts and Sciences Biologically Soft Yet Ultrasonically Active Materials This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. Spring 2018 2018 Materials Science Acoustics Chemistry Attenuation, Composite, Elastomer, Polymer, Soft, Ultrasound eng Doctor of Philosophy Dissertation Chemistry Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark H. Schoenfisch Thesis advisor text University of North Carolina at Chapel Hill Degree granting institution Matthew Everhart Creator Department of Chemistry College of Arts and Sciences This dissertation establishes the acoustic nature of three classes of soft polymeric materials: (i) thiol-ene linear elastomers with poly(dimethylsiloxane) (PDMS) network strands, (ii) brush- and comb-like elastomers with PDMS sidechains and n-butyl acrylate spacers, and (iii) ABA-triblock plastomer copolymers with linear poly(methyl methacrylate) (PMMA) A-blocks and brush PDMS B-blocks. Specifically, the acoustic attenuation, α, and the longitudinal speed of sound, 〖C_¬〗_l, are determined as functions of Young’s modulus, E_0, by applying pulse-echo methods to obtain ultrasonic time-of-flight measurements. With corresponding mechanical analysis, it is shown that these tissue-soft but solvent-free materials inhabit a unique region in the acoustomechanical space of α and E_0, with α ranging from 1.2 to 5.9 dB/cm at 1 MHz and E_0 ranging from 2.9 to 185 kPa. Finally, it is shown with the plastomer and thiol-ene systems that the sub-atmospheric moduli additionally permit the complete in situ expansion of thermoexpandable fillers – and that this in turn enables precise control of composite modulus, attenuation, speed of sound, and volume. Finally, it is demonstrated that these composites (i) expand with millimeter resolution under high-intensity focused ultrasound (HIFU) and (ii) yield considerable contrast in ultrasound imaging. 2018-05 2018 Materials Science Acoustics Chemistry Attenuation; Composite; Elastomer; Polymer; Soft; Ultrasound eng Doctor of Philosophy Dissertation Wei You Thesis advisor Sergei Sheiko Thesis advisor Scott Warren Thesis advisor James Cahoon Thesis advisor Mark H. Schoenfisch Thesis advisor text University of North Carolina at Chapel Hill Degree granting institution Everhart_unc_0153D_17926.pdf uuid:675d8be4-35ff-443e-b438-7afa0d90e1f2 2020-06-13T00:00:00 2018-05-30T13:40:46Z proquest application/pdf 2175955