Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide.
The synthesis and characterisation of constrained geometry scandium permethylindenyl chloride, aryloxide and borohydride complexes Me2SB(tBuN,I*)Sc(Cl)(THF) (1), Me2SB(tBuN,I*)Sc(O-2,6-iPr-C6H3)(THF) (2), Me2SB(tBuN,I*)Sc(O-2,4-tBu-C6H3)(THF) (3) and Me2SB(tBuN,I*)Sc(BH4)(THF) (4) are reported. The...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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Royal Society of Chemistry
2019
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| _version_ | 1826291137846968320 |
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| author | Diteepeng, N Buffet, J Turner, Z O'Hare, D |
| author_facet | Diteepeng, N Buffet, J Turner, Z O'Hare, D |
| author_sort | Diteepeng, N |
| collection | OXFORD |
| description | The synthesis and characterisation of constrained geometry scandium permethylindenyl chloride, aryloxide and borohydride complexes Me2SB(tBuN,I*)Sc(Cl)(THF) (1), Me2SB(tBuN,I*)Sc(O-2,6-iPr-C6H3)(THF) (2), Me2SB(tBuN,I*)Sc(O-2,4-tBu-C6H3)(THF) (3) and Me2SB(tBuN,I*)Sc(BH4)(THF) (4) are reported. The activity of complexes 1-4 as initiators for the ring-opening polymerisation (ROP) of l- and rac-lactide is presented. The ROP of l- and rac-lactide using complexes 2 and 3 show first-order dependence on monomer concentration, and produced isotactic polylactide (PLA) and moderately heterotactic PLA (Pr = 0.68-0.72), respectively. Good agreement between experimental and theoretical molecular weights of PLA (Mn) and relatively narrow dispersities (Mw/Mn < 1.20) were obtained. Complex 4 showed higher activity for ROP of l- and rac-lactide than 2 or 3, with second-order dependence on monomer concentrations. However, poorly controlled molecular weights and lower heteroselectivity (Pr = 0.61-0.67) were observed. The effect of temperature and catalyst concentration for the ROP of l-lactide using 2 and 3 was also studied. |
| first_indexed | 2024-03-07T02:54:53Z |
| format | Journal article |
| id | oxford-uuid:aeedd5af-be48-4b3c-890b-b440684d75e5 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T02:54:53Z |
| publishDate | 2019 |
| publisher | Royal Society of Chemistry |
| record_format | dspace |
| spelling | oxford-uuid:aeedd5af-be48-4b3c-890b-b440684d75e52022-03-27T03:46:08ZConstrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:aeedd5af-be48-4b3c-890b-b440684d75e5EnglishSymplectic Elements at OxfordRoyal Society of Chemistry2019Diteepeng, NBuffet, JTurner, ZO'Hare, DThe synthesis and characterisation of constrained geometry scandium permethylindenyl chloride, aryloxide and borohydride complexes Me2SB(tBuN,I*)Sc(Cl)(THF) (1), Me2SB(tBuN,I*)Sc(O-2,6-iPr-C6H3)(THF) (2), Me2SB(tBuN,I*)Sc(O-2,4-tBu-C6H3)(THF) (3) and Me2SB(tBuN,I*)Sc(BH4)(THF) (4) are reported. The activity of complexes 1-4 as initiators for the ring-opening polymerisation (ROP) of l- and rac-lactide is presented. The ROP of l- and rac-lactide using complexes 2 and 3 show first-order dependence on monomer concentration, and produced isotactic polylactide (PLA) and moderately heterotactic PLA (Pr = 0.68-0.72), respectively. Good agreement between experimental and theoretical molecular weights of PLA (Mn) and relatively narrow dispersities (Mw/Mn < 1.20) were obtained. Complex 4 showed higher activity for ROP of l- and rac-lactide than 2 or 3, with second-order dependence on monomer concentrations. However, poorly controlled molecular weights and lower heteroselectivity (Pr = 0.61-0.67) were observed. The effect of temperature and catalyst concentration for the ROP of l-lactide using 2 and 3 was also studied. |
| spellingShingle | Diteepeng, N Buffet, J Turner, Z O'Hare, D Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title | Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title_full | Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title_fullStr | Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title_full_unstemmed | Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title_short | Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. |
| title_sort | constrained geometry scandium permethylindenyl complexes for the ring opening polymerisation of l and rac lactide |
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