Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study
In this work, we successfully synthesized high thermal stable 1,n-<i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane <i>bis</i>hexafluorophosphates (1,n-<i>bis</i>[Bim][PF<sub>6</sub>], n = 4, 6, 8, and 10) catalysts in 55–7...
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MDPI AG
2021-12-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/13/24/4290 |
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| author | Nathaporn Cheechana Wachara Benchaphanthawee Natthapol Akkravijitkul Puracheth Rithchumpon Thiti Junpirom Wanich Limwanich Winita Punyodom Nawee Kungwan Chanisorn Ngaojampa Praput Thavornyutikarn Puttinan Meepowpan |
| author_facet | Nathaporn Cheechana Wachara Benchaphanthawee Natthapol Akkravijitkul Puracheth Rithchumpon Thiti Junpirom Wanich Limwanich Winita Punyodom Nawee Kungwan Chanisorn Ngaojampa Praput Thavornyutikarn Puttinan Meepowpan |
| author_sort | Nathaporn Cheechana |
| collection | DOAJ |
| description | In this work, we successfully synthesized high thermal stable 1,n-<i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane <i>bis</i>hexafluorophosphates (1,n-<i>bis</i>[Bim][PF<sub>6</sub>], n = 4, 6, 8, and 10) catalysts in 55–70% yields from imidazole which were applied as non-toxic DILs catalysts with 1-butanol as initiator for the bulk ROP of <i>ε</i>-caprolactone (CL) in the varied ratio of CL/<i>n</i>BuOH/1,4-<i>bis</i>[Bim][PF<sub>6</sub>] from 200/1.0/0.25–4.0 to 700/1.0/0.25–4.0 by mol%. The result found that the optimal ratio of CL/<i>n</i>BuOH/1,4-<i>bis</i>[Bim][PF<sub>6</sub>] 400/1.0/0.5 mol% at 120 °C for 72 h led to the polymerization conversions higher than 95%, with the molecular weight (<i>M</i><sub>w</sub>) of PCL 20,130 g mol<sup>−1</sup> (<i>Đ</i>~1.80). The polymerization rate of CL increased with the decreasing linker chain length of ionic liquids. Moreover, the mechanistic study was investigated by DFT using B3LYP (6–31G(d,p)) as basis set. The most plausible mechanism included the stepwise and coordination insertion in which the alkoxide insertion step is the rate-determining step. |
| first_indexed | 2024-03-10T03:16:01Z |
| format | Article |
| id | doaj.art-dd2e857b9ffa4f29abc3200530378765 |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-10T03:16:01Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-dd2e857b9ffa4f29abc32005303787652023-11-23T10:14:14ZengMDPI AGPolymers2073-43602021-12-011324429010.3390/polym13244290Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic StudyNathaporn Cheechana0Wachara Benchaphanthawee1Natthapol Akkravijitkul2Puracheth Rithchumpon3Thiti Junpirom4Wanich Limwanich5Winita Punyodom6Nawee Kungwan7Chanisorn Ngaojampa8Praput Thavornyutikarn9Puttinan Meepowpan10Department of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandFaculty of Sciences and Agricultural Technology, Rajamangala University of Technology Lanna, 128 Huay Kaew Road, Chiang Mai 50300, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandDepartment of Chemistry, Faculty of Science, Chiang Mai University, 239 Huay Kaew Road, Chiang Mai 50200, ThailandIn this work, we successfully synthesized high thermal stable 1,n-<i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane <i>bis</i>hexafluorophosphates (1,n-<i>bis</i>[Bim][PF<sub>6</sub>], n = 4, 6, 8, and 10) catalysts in 55–70% yields from imidazole which were applied as non-toxic DILs catalysts with 1-butanol as initiator for the bulk ROP of <i>ε</i>-caprolactone (CL) in the varied ratio of CL/<i>n</i>BuOH/1,4-<i>bis</i>[Bim][PF<sub>6</sub>] from 200/1.0/0.25–4.0 to 700/1.0/0.25–4.0 by mol%. The result found that the optimal ratio of CL/<i>n</i>BuOH/1,4-<i>bis</i>[Bim][PF<sub>6</sub>] 400/1.0/0.5 mol% at 120 °C for 72 h led to the polymerization conversions higher than 95%, with the molecular weight (<i>M</i><sub>w</sub>) of PCL 20,130 g mol<sup>−1</sup> (<i>Đ</i>~1.80). The polymerization rate of CL increased with the decreasing linker chain length of ionic liquids. Moreover, the mechanistic study was investigated by DFT using B3LYP (6–31G(d,p)) as basis set. The most plausible mechanism included the stepwise and coordination insertion in which the alkoxide insertion step is the rate-determining step.https://www.mdpi.com/2073-4360/13/24/4290<i>bis</i>(<i>n</i>-(<i>n</i>′-butylimidazolium)alkane dicationic ionic liquidsring-opening polymerization<i>ε</i>-caprolactonemetal-free catalystdensity functional theory |
| spellingShingle | Nathaporn Cheechana Wachara Benchaphanthawee Natthapol Akkravijitkul Puracheth Rithchumpon Thiti Junpirom Wanich Limwanich Winita Punyodom Nawee Kungwan Chanisorn Ngaojampa Praput Thavornyutikarn Puttinan Meepowpan Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study Polymers <i>bis</i>(<i>n</i>-(<i>n</i>′-butylimidazolium)alkane dicationic ionic liquids ring-opening polymerization <i>ε</i>-caprolactone metal-free catalyst density functional theory |
| title | Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study |
| title_full | Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study |
| title_fullStr | Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study |
| title_full_unstemmed | Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study |
| title_short | Organocatalytic Ring-Opening Polymerization of <i>ε</i>-Caprolactone Using <i>bis</i>(<i>N</i>-(<i>N</i>′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study |
| title_sort | organocatalytic ring opening polymerization of i ε i caprolactone using i bis i i n i i n i butylimidazolium alkane dicationic ionic liquids as the metal free catalysts polymer synthesis kinetics and dft mechanistic study |
| topic | <i>bis</i>(<i>n</i>-(<i>n</i>′-butylimidazolium)alkane dicationic ionic liquids ring-opening polymerization <i>ε</i>-caprolactone metal-free catalyst density functional theory |
| url | https://www.mdpi.com/2073-4360/13/24/4290 |
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