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Xu Y, Cui R, Han Y, Jiang J, Hu D, Zhao L, Xi Z. Efficient Alcoholysis of Poly(ethylene terephthalate) by Using Supercritical Carbon Dioxide as a Green Solvent. Polymers (Basel) 2024; 16:1564. [PMID: 38891510 PMCID: PMC11174447 DOI: 10.3390/polym16111564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 05/26/2024] [Accepted: 05/30/2024] [Indexed: 06/21/2024] Open
Abstract
In order to reduce the environmental impact of poly(ethylene terephthalate) (PET) plastic waste, supercritical fluids were used to facilitate effective recovery via improved solvent effects. This work focuses on the mechanisms of supercritical CO2 (ScCO2) during the alcoholysis processing of PET using systematic experiments and molecular dynamics (MD) simulations. The results of the alcoholysis experiment indicated that PET chips can be completely depolymerized within only an hour at 473 K assisted with ScCO2 at an optimal molar ratio of CO2/ethanol of 0.2. Random scission of PET dominates the early stage of the depolymerization reaction process, while specific scission dominates the following stage. Correspondingly, molecular dynamics (MD) simulations revealed that the solubilization and self-diffusion properties of ScCO2 facilitate the transportation of alcohol molecules into the bulk phase of PET, which leads to an accelerated diffusion of both oligomers and small molecules in the system. However, the presence of excessive CO2 has a negative impact on depolymerization by weakening the hydrogen bonding between polyester chain segments and ethanol, as well as decreasing the swelling degree of PET. These data provide a deep understanding of PET degradation by alcohols and the enhancement of ScCO2. It should be expected to achieve an efficient and high-yield depolymerization process of wasted polyesters assisted with ScCO2 at a relatively low temperature.
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Affiliation(s)
- Yiwei Xu
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
| | - Ran Cui
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
| | - Yuqing Han
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
| | - Jie Jiang
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
| | - Dongdong Hu
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
| | - Ling Zhao
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
| | - Zhenhao Xi
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Y.X.); (R.C.); (Y.H.); (J.J.); (L.Z.)
- Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
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You L, Long Z, You Z, Ge D, Yang X, Xu F, Hashemi M, Diab A. Review of recycling waste plastics in asphalt paving materials. JOURNAL OF TRAFFIC AND TRANSPORTATION ENGINEERING (ENGLISH EDITION) 2022. [DOI: 10.1016/j.jtte.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Denayer M, Vekeman J, Tielens F, De Proft F. Towards a predictive model for polymer solubility using the noncovalent interaction index: polyethylene as a case study. Phys Chem Chem Phys 2021; 23:25374-25387. [PMID: 34751286 DOI: 10.1039/d1cp04346c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work we present the development of a novel, quantitative solubility descriptor based on the non-covalent interaction index. It is presented as a more insightful alternative to Hansen's solubility parameters and the COSMO model to assess and predict polymer solubility in different solvents. To this end, we studied the solvation behaviour as a function of the chain length of a single chain of arguably the most simple polymer, polyethylene, in anisole (solvent) and methanol (poor solvent) via molecular dynamics simulations. It was found that in anisole the solute maximized its interface with the solvent, whereas in methanol the macromolecule formed rod-like structures by folding on itself once the chain length surpassed a certain barrier. We assessed this behaviour - which can be related to solubility - quantitatively and qualitatively via well-known descriptors, namely the solvation free energy, and the solvent accessible surface area. In addition, we propose the non-covalent interaction (NCI) index as a versatile descriptor, providing information on the strength, as well as the nature, of the solute-solvent interactions, the solute's intramolecular interactions and on the solute's conformation, both qualitatively and quantitatively. Finally, as a quantitative measure for solubility, defined in this context as the solute's tendency to maximize its interactions with the solvent, we propose two new NCI-based descriptors: the relative integrated NCI density and the integrated NCI difference. The former represents the quantitative difference in solute-solvent interactions between a fully extended coil and the actual conformation during simulation and the latter the quantitative difference between the intermolecular (solute-solvent) and the intramolecular (in the solute) non-covalent interactions. The easy interpretation and calculation of these novel quantities open up the possibility of fast, reliable and insightful high-throughput screening of different (anti)solvent and solute combinations.
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Affiliation(s)
- Mats Denayer
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
| | - Jelle Vekeman
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
| | - Frederik Tielens
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
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Peng K, Shahab S, Mirzaeifar R. Interaction of high-intensity focused ultrasound with polymers at the atomistic scale. NANOTECHNOLOGY 2021; 32:045707. [PMID: 33036012 DOI: 10.1088/1361-6528/abbfd2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Experiments show that high-intensity focused ultrasound (HIFU) is a promising stimulus with multiple superior and unique capabilities to induce localized heating and achieve temporal and spatial thermal effects in the polymers, noninvasively. When polymers are subjected to HIFU, they heat up differently compared to the case they are subjected to heat sources directly; however, the origins of this difference are still entirely unknown. We hypothesize that the difference in the macroscale response of polymers subjected to HIFU strongly depends on the polymer chains, composition, and structure, i.e. being crystalline or amorphous. In this work, this hypothesis is investigated by molecular dynamics studies at the atomistic level and verified by experiments at the macroscopic scale. The results show that the viscoelasticity, measured by stress-strain phase lag, the reptation motion of the chains, and the vibration-induced local mobility quantified by the root mean square fluctuation contribute to the observed difference in the HIFU-induced thermal effects. This unravels the unknown mechanisms behind stimulating the polymers by HIFU, and paves the way in front of using this method in future applications.
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Affiliation(s)
- Kaiyuan Peng
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States of America
| | - Shima Shahab
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States of America
| | - Reza Mirzaeifar
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States of America
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Hosseini SZ, Bozorgmehr MR, Masrurnia M, Beyramabadi SA. Study of the effects of methanol, ethanol and propanol alcohols as Co-solvents on the interaction of methimazole, propranolol and phenazopyridine with carbon dioxide in supercritical conditions by molecular dynamics. J Supercrit Fluids 2018. [DOI: 10.1016/j.supflu.2018.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Yoon TJ, Lee YW. Current theoretical opinions and perspectives on the fundamental description of supercritical fluids. J Supercrit Fluids 2018. [DOI: 10.1016/j.supflu.2017.11.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Feng H, Gao W, Su L, Sun Z, Chen L. MD simulation study of the diffusion and local structure of n-alkanes in liquid and supercritical methanol at infinite dilution. J Mol Model 2017; 23:195. [PMID: 28560578 DOI: 10.1007/s00894-017-3366-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Accepted: 05/09/2017] [Indexed: 10/19/2022]
Abstract
The diffusion coefficients of 14 n-alkanes (ranging from methane to n-tetradecane) in liquid and supercritical methanol at infinite dilution (at a pressure of 10.5 MPa and at temperatures of 299 K and 515 K) were deduced via molecular dynamics simulations. Values for the radial distribution function, coordination number, and number of hydrogen bonds were then calculated to explore the local structure of each fluid. The flexibility of the n-alkane (as characterized by the computed dihedral distribution, end-to-end distance, and radius of gyration) was found to be a major influence and hydrogen bonding to be a minor influence on the local structure. Hydrogen bonding reduces the flexibility of the n-alkane, whereas increasing the temperature enhances its flexibility, with temperature having a greater effect than hydrogen bonding on flexibility. Graphical abstract The flexibility of the alkane is a major influence and the hydrogen bonding is a minor influence on the first solvation shell; the coordination numbers of long-chain n-alkanes in the first solvation shell are rather low.
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Affiliation(s)
- Huajie Feng
- School of Chemistry and Chemical Engineering, Hainan Normal University, Haikou, 571158, People's Republic of China
| | - Wei Gao
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, People's Republic of China
| | - Li Su
- Hainan Entry-Exit Inspection and Quarantine Technology Center, Haikou, 570311, People's Republic of China
| | - Zhenfan Sun
- School of Chemistry and Chemical Engineering, Hainan Normal University, Haikou, 571158, People's Republic of China.
| | - Liuping Chen
- KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, 510275, People's Republic of China.
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