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Savale N, Tarasova E, Krasnou I, Kudrjašova M, Rjabovs V, Reile I, Heinmaa I, Krumme A. Optimization and degradation studies of cellulose transesterification to palmitate esters in superbase ionic liquid. Carbohydr Res 2024; 537:109047. [PMID: 38359696 DOI: 10.1016/j.carres.2024.109047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
Cellulose palmitates (CPs) were synthesized with varying degrees of substitution (DS) via a catalyst-free, homogeneous transesterification of cellulose in a novel superbase ionic liquid (SB-IL) system, specifically 5-methyl-1,5,7-triaza-bicyclo[4.3.0]non-6-enium acetate [mTBNH][OAc], combined with dimethyl sulfoxide (DMSO) as a co-solvent, using vinyl palmitate as the acylating agent. We examined the influence of reaction temperature, reaction time, and the molar ratio of vinyl palmitate to anhydroglucose unit (AGU) on the DS, which ranged from 0.5 to 2.3 under the given conditions. Notably, the reaction order of the three hydroxy groups was C6-OH > C2-OH > C3-OH. To elucidate the chemical structure of CPs and confirm the transesterification process, various spectroscopic techniques including 1H nuclear magnetic resonance (NMR), 13C NMR, heteronuclear single quantum correlation (HSQC), and solid-state NMR were employed. Higher reaction temperatures and extended reaction times led to a decrease in the DS of CPs, potentially due to the degradation of some of the involved chemicals during the transesterification process. We also investigated the stability of the pure ionic liquid (IL) and the IL + DMSO solvent system at elevated temperatures by heating them at 100 °C for 5 h, confirming their chemical integrity through 1H NMR analysis. Additionally, we assessed the compatibility between the solvent system and cellulose by subjecting a mixture of cellulose and the solvent system to 100 °C for 5 h. To compare the structures of untreated cellulose and regenerated cellulose, Fourier transform infrared (FT-IR) spectroscopy was employed. Furthermore, we determined the molar mass of both untreated cellulose and regenerated cellulose, as well as CPs synthesized at higher reaction temperatures and longer durations, using intrinsic viscosity measurements. Lastly, we examined the solubility properties of CPs.
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Affiliation(s)
- N Savale
- School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia.
| | - E Tarasova
- School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia
| | - I Krasnou
- School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia
| | - M Kudrjašova
- School of Science, Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618, Tallinn, Estonia
| | - V Rjabovs
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
| | - I Reile
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
| | - I Heinmaa
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618, Tallinn, Estonia
| | - A Krumme
- School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia
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Chen M, Ou B, Guo Y, Guo Y, Kang Y, Liu H, Yan J, Tian L. Preparation of an environmentally friendly antifouling degradable polyurethane coating material based on medium-length fluorinated diols. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2018. [DOI: 10.1080/10601325.2018.1470466] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Meilong Chen
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Baoli Ou
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
- State Key Laboratory of Tribology, Tsinghua University, Tsinghua University, Beijing, China
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
- State Key Laboratory of Powder Metallurgy, Central South University, Changsha, China
| | - Yuanjun Guo
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Yan Guo
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Yonghai Kang
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Huiyang Liu
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Jianhui Yan
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
| | - Li Tian
- School of Materials Science and Engineering, Hunan University of Science and Technology, Hunan Provincial Key Defense Laboratory of High Temperature Wear-resisting Materials and Preparation Technology, Hunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine Polymers, Key Laboratory of Theoretical Organic Chemistry and Function Molecule Ministry of Education, Xiangtan, China
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