CO2/Propylene Oxide Copolymerization with a Bifunctional Catalytic System Composed of Multiple Ammonium Salts and a Salen Cobalt Complex Containing Sulfonate Anions
- 주제(키워드) Salen , CO2 , Copolymerization , Multiple ammonium salts
- 주제(DDC) 547
- 발행기관 아주대학교
- 지도교수 이분열
- 발행년도 2022
- 학위수여년월 2022. 2
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 실제URI http://www.dcollection.net/handler/ajou/000000031452
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
A (Salen)Co(III) complex tethering four quaternary ammonium salts with covalent bonds is one of the most highly active catalysts for CO2/epoxide copolymerization. In this work, we aimed to prepare similar (Salen)Co(III) complexes to which quaternary ammonium salts are linked via ionic interactions. Thus, multiple ammonium salts containing 2-5 quaternary ammonium salt units and (Salen)Co(III) complexes containing one or two SO3[PhNH3]+ moieties were prepared. A binary catalytic system composed of the prepared multiple ammonium salts and the prepared (Salen)Co(III) complex containing -SO3-[(nBu)4N]+ moieties showed high activity (TOF, 15004500 h1) for CO2/propylene oxide (PO) copolymerization, whereas a combination of the multiple ammonium salts and the conventional (Salen)Co(III) complex not containing -SO3-[(nBu)4N]+ moieties was inactive under the identical polymerization conditions of [PO]/[Co] = 20000. However, a substantial amount of cyclic carbonate was concomitantly generated, especially when a (Salen)Co(III) complex containing two -SO3-[(nBu)4N]+ moieties was used (2530%). This side-reaction could be mitigated by ca. 50% by employing a (Salen)Co(III) complex containing one -SO3-[(nBu)4N]+ moiety. Cyclic carbonate generation can reasonably be ascribed to ammonium salts ([(nBu)4N]+[carbonate]-) not linked to the (Salen)Co(III) complex formed in the binary catalytic system.
more목차
1 Introduction 1
2 Experimental Section 3
2.1 General Remarks 3
2.2 Preparation of 1 3
2.3 Preparation of 2 [X = I] 4
2.4 Preparation of 3 [X = I] 4
2.5 Preparation of 4 [X = I] 5
2.6 Preparation of 5 [X = I] 5
2.7 Conversion of 4 [X = I] to 4 [X = DNP] 6
2.8 Preperation of 6 6
2.9 Preperation of 7 6
2.10 Preperation of 8 7
2.11 Preperation of 9 7
2.12 Preperation of 10 7
2.13 Preperation of 11 8
2.14 Preparation of a mixture of 12 and 10 8
2.15 Preparation of a mixture of 13 and 11 9
2.16 Preperation of 14 10
2.17 Typical procedure for CO2/PO copolymerization 10
3 Result and Discussion 11
3.1 Preparation of multiple ammonium salts 11
3.2 Preparation of (Salen)Co(III) complexes tethering sulfonate anion groups 13
3.3 CO2/propylene oxide copolymerization 16
4 Conclusion 19
5 Acknowledgements 19
6 Reference 20
