Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers
<p>The thesis describes the use of heterodinuclear Mg(II)M(II) complexes (M = transition metals) as catalysts for the ring-opening copolymerisation (ROCOP) of epoxides and anhydrides, and epoxides and CO2.</p> <p><strong>Chapter 1</strong> provides an introduction to R...
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| Other Authors: | |
| Format: | Thesis |
| Language: | English |
| Published: |
2022
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| _version_ | 1826308060903112704 |
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| author | Rosetto, G |
| author2 | Williams, C |
| author_facet | Williams, C Rosetto, G |
| author_sort | Rosetto, G |
| collection | OXFORD |
| description | <p>The thesis describes the use of heterodinuclear Mg(II)M(II) complexes (M = transition metals) as catalysts for the ring-opening copolymerisation (ROCOP) of epoxides and anhydrides, and epoxides and CO2.</p>
<p><strong>Chapter 1</strong> provides an introduction to ROCOP, outlining the mechanism and catalyst developments, with a particular focus on epoxides and CO2. Routes towards the construction of ROCOP-derived block copolymers, and the concept of switch catalysis are also described.</p>
<p><strong>Chapter 2</strong> details the ROCOP of norbornene anhydride (NA) and cyclohexene oxide (CHO) for a series of heterodinuclear Mg(II)M(II) complexes, were M = first row transition metals. A representative rate law is proposed on the basis of kinetic experiments for the most active complex, Mg(II)Co(II). Subsequently, monomer insertion selectivity for ROCOP of tricyclic anhydride (TCA), cyclohexene oxide (CHO), and CO2 is determined for complexes Zn(II)Zn(II), Mg(II)Mg(II), Mg(II)Zn(II) and Mg(II)Co(II). It is found that Zn(II)Zn(II) selectively forms poly(TCA-alt-CHO), Mg(II)Zn(II) forms poly((TCA-alt-CHO)-ran-cyclohexene carbonate), and Mg(II)Mg(II) and Mg(II)Co(II) selectively form poly(cyclohexene carbonate) (PCHC).</p>
<p><strong>Chapter 3</strong> describes the synthesis of multi-block copolymers, up to heptablock, of PCHC and PE in one-pot by changing the headspace between CO2 and N2 gas at 1 bar, using the Mg(II)Co(II) catalyst. Switch catalysis is also used to make a pentablock polymer, the final block afforded by the ring-opening polymerisation of ε-caprolactone (CL).</p>
<p><strong>Chapter 4</strong> details the synthesis of and characterisation of a Mg(II)Co(II) complex with organometallic co-ligands. It is demonstrated that when using this complex for the ROCOP of CO2 and epoxides, in addition with bifunctional protic chain transfer agents, high molar mass polycarbonates with monodisperse distributions are yielded. Mechanical data is obtained for a high molar mass poly(vinyl-cyclohexene carbonate) (PvCHC).</p>
<p><strong>Chapter 5</strong> details the synthesis and characterisation of Ni(II) phenoxyiminato complexes, and their application in ethylene polymerisation under various conditions. Three different strategies towards Ni(II) alkoxide complexes are attempted, as they can operate as initiators for either ROP or ROCOP processes.</p>
<p><strong>Chapter 6</strong> summarises the key findings of the thesis and suggests future research which could follow the work described.</p>
<p><strong>Chapter 7</strong> provides experimental details for Chapters 2–5.</p>
<p><strong>Appendix</strong> contains supplementary figures and data for Chapters 2–5.</p> |
| first_indexed | 2024-03-07T07:12:23Z |
| format | Thesis |
| id | oxford-uuid:7f362423-ec8f-4ce9-930b-0846c52fd523 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T07:12:23Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | oxford-uuid:7f362423-ec8f-4ce9-930b-0846c52fd5232022-07-11T10:26:27ZMg(II) heterodinuclear catalysts for the synthesis of oxygenated polymersThesishttp://purl.org/coar/resource_type/c_db06uuid:7f362423-ec8f-4ce9-930b-0846c52fd523Homogeneous catalysisPolymersEnglishHyrax Deposit2022Rosetto, GWilliams, C<p>The thesis describes the use of heterodinuclear Mg(II)M(II) complexes (M = transition metals) as catalysts for the ring-opening copolymerisation (ROCOP) of epoxides and anhydrides, and epoxides and CO2.</p> <p><strong>Chapter 1</strong> provides an introduction to ROCOP, outlining the mechanism and catalyst developments, with a particular focus on epoxides and CO2. Routes towards the construction of ROCOP-derived block copolymers, and the concept of switch catalysis are also described.</p> <p><strong>Chapter 2</strong> details the ROCOP of norbornene anhydride (NA) and cyclohexene oxide (CHO) for a series of heterodinuclear Mg(II)M(II) complexes, were M = first row transition metals. A representative rate law is proposed on the basis of kinetic experiments for the most active complex, Mg(II)Co(II). Subsequently, monomer insertion selectivity for ROCOP of tricyclic anhydride (TCA), cyclohexene oxide (CHO), and CO2 is determined for complexes Zn(II)Zn(II), Mg(II)Mg(II), Mg(II)Zn(II) and Mg(II)Co(II). It is found that Zn(II)Zn(II) selectively forms poly(TCA-alt-CHO), Mg(II)Zn(II) forms poly((TCA-alt-CHO)-ran-cyclohexene carbonate), and Mg(II)Mg(II) and Mg(II)Co(II) selectively form poly(cyclohexene carbonate) (PCHC).</p> <p><strong>Chapter 3</strong> describes the synthesis of multi-block copolymers, up to heptablock, of PCHC and PE in one-pot by changing the headspace between CO2 and N2 gas at 1 bar, using the Mg(II)Co(II) catalyst. Switch catalysis is also used to make a pentablock polymer, the final block afforded by the ring-opening polymerisation of ε-caprolactone (CL).</p> <p><strong>Chapter 4</strong> details the synthesis of and characterisation of a Mg(II)Co(II) complex with organometallic co-ligands. It is demonstrated that when using this complex for the ROCOP of CO2 and epoxides, in addition with bifunctional protic chain transfer agents, high molar mass polycarbonates with monodisperse distributions are yielded. Mechanical data is obtained for a high molar mass poly(vinyl-cyclohexene carbonate) (PvCHC).</p> <p><strong>Chapter 5</strong> details the synthesis and characterisation of Ni(II) phenoxyiminato complexes, and their application in ethylene polymerisation under various conditions. Three different strategies towards Ni(II) alkoxide complexes are attempted, as they can operate as initiators for either ROP or ROCOP processes.</p> <p><strong>Chapter 6</strong> summarises the key findings of the thesis and suggests future research which could follow the work described.</p> <p><strong>Chapter 7</strong> provides experimental details for Chapters 2–5.</p> <p><strong>Appendix</strong> contains supplementary figures and data for Chapters 2–5.</p> |
| spellingShingle | Homogeneous catalysis Polymers Rosetto, G Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title | Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title_full | Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title_fullStr | Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title_full_unstemmed | Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title_short | Mg(II) heterodinuclear catalysts for the synthesis of oxygenated polymers |
| title_sort | mg ii heterodinuclear catalysts for the synthesis of oxygenated polymers |
| topic | Homogeneous catalysis Polymers |
| work_keys_str_mv | AT rosettog mgiiheterodinuclearcatalystsforthesynthesisofoxygenatedpolymers |