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Fang DX, Chen MJ, Zeng FR, Guo SQ, He L, Liu BW, Huang SC, Zhao HB, Wang YZ. Self-evolutionary recycling of flame-retardant polyurethane foam enabled by controllable catalytic cleavage. MATERIALS HORIZONS 2024. [PMID: 38742392 DOI: 10.1039/d4mh00039k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Polyurethane (PU) foams, pivotal in modern life, face challenges suh as fire hazards and environmental waste burdens. The current reliance of PU on potentially ecotoxic halogen-/phosphorus-based flame retardants impedes large-scale material recycling. Here, our demonstrated controllable catalytic cracking strategy, using cesium salts, enables self-evolving recycling of flame-retardant PU. The incorporation of cesium citrates facilitates efficient urethane bond cleavage at low temperatures (160 °C), promoting effective recycling, while encouraging pyrolytic rearrangement of isocyanates into char at high temperatures (300 °C) for enhanced PU fire safety. Even in the absence of halogen/phosphorus components, this foam exhibits a substantial increase in ignition time (+258.8%) and a significant reduction in total smoke release (-79%). This flame-retardant foam can be easily recycled into high-quality polyol under mild conditions, 60 °C lower than that for the pure foam. Notably, the trace amounts of cesium gathered in recycled polyols stimulate the regenerated PU to undergo self-evolution, improving both flame-retardancy and mechanical properties. Our controllable catalytic cracking strategy paves the way for the self-evolutionary recycling of high-performance firefighting materials.
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Affiliation(s)
- Dan-Xuan Fang
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Ming-Jun Chen
- School of Science, Xihua University, Chengdu, 610039, China
| | - Fu-Rong Zeng
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Shuai-Qi Guo
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Lei He
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Bo-Wen Liu
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | | | - Hai-Bo Zhao
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
| | - Yu-Zhong Wang
- College of Architecture and Environment, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu, 610064, China.
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2
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Marhoon A, Hernandez MLH, Billy RG, Müller DB, Verones F. Mapping Plastic and Plastic Additive Cycles in Coastal Countries: A Norwegian Case Study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:8336-8348. [PMID: 38703133 PMCID: PMC11097394 DOI: 10.1021/acs.est.3c09176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 05/06/2024]
Abstract
The growing environmental consequences caused by plastic pollution highlight the need for a better understanding of plastic polymer cycles and their associated additives. We present a novel, comprehensive top-down method using inflow-driven dynamic probabilistic material flow analysis (DPMFA) to map the plastic cycle in coastal countries. For the first time, we covered the progressive leaching of microplastics to the environment during the use phase of products and modeled the presence of 232 plastic additives. We applied this methodology to Norway and proposed initial release pathways to different environmental compartments. 758 kt of plastics distributed among 13 different polymers was introduced to the Norwegian economy in 2020, 4.4 Mt was present in in-use stocks, and 632 kt was wasted, of which 15.2 kt (2.4%) was released to the environment with a similar share of macro- and microplastics and 4.8 kt ended up in the ocean. Our study shows tire wear rubber as a highly pollutive microplastic source, while most macroplastics originated from consumer packaging with LDPE, PP, and PET as dominant polymers. Additionally, 75 kt of plastic additives was potentially released to the environment alongside these polymers. We emphasize that upstream measures, such as consumption reduction and changes in product design, would result in the most positive impact for limiting plastic pollution.
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Affiliation(s)
- Ahmed Marhoon
- Industrial
Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), Trondheim NO-7034, Norway
| | | | - Romain Guillaume Billy
- Industrial
Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), Trondheim NO-7034, Norway
| | - Daniel Beat Müller
- Industrial
Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), Trondheim NO-7034, Norway
| | - Francesca Verones
- Industrial
Ecology Programme, Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), Trondheim NO-7034, Norway
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3
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Chen S, Hu YH. Complete Degradation of Polyolefin Plastic Wastes to High-Value Products. CHEMSUSCHEM 2024:e202301449. [PMID: 38647354 DOI: 10.1002/cssc.202301449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 04/20/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
Plastic wastes continuously accumulate, causing critical environmental issues. It is urgent to develop efficient strategies to convert them to valuable products. Very recently, two novel approaches for plastic recycling were reported by Huber et al. (Science, 2023, 381, 660-666) and Liu et al. (Science, 2023, 381, 666-671), where polyethylene (PE) and polypropylene (PP) plastics were converted into potentially valuable products, such as alcohols, aldehydes, surfactants, and detergents. The two processes achieved complete degradation, high selectivity of target products, as well as high values of products, showing economic feasibility for industrial scale-up. These breakthroughs for plastic recycling are highlighted in this article.
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Affiliation(s)
- Shaoqin Chen
- Department of Materials Science and Engineering, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931-1295, USA
| | - Yun Hang Hu
- Department of Materials Science and Engineering, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931-1295, USA
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4
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Li M, Sun G, Wang Z, Zhang X, Peng J, Jiang F, Li J, Tao S, Liu Y, Pan Y. Structural Design of Single-Atom Catalysts for Enhancing Petrochemical Catalytic Reaction Process. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2313661. [PMID: 38499342 DOI: 10.1002/adma.202313661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/02/2024] [Indexed: 03/20/2024]
Abstract
Petroleum, as the "lifeblood" of industrial development, is the important energy source and raw material. The selective transformation of petroleum into high-end chemicals is of great significance, but still exists enormous challenges. Single-atom catalysts (SACs) with 100% atom utilization and homogeneous active sites, promise a broad application in petrochemical processes. Herein, the research systematically summarizes the recent research progress of SACs in petrochemical catalytic reaction, proposes the role of structural design of SACs in enhancing catalytic performance, elucidates the catalytic reaction mechanisms of SACs in the conversion of petrochemical processes, and reveals the high activity origins of SACs at the atomic scale. Finally, the key challenges are summarized and an outlook on the design, identification of active sites, and the appropriate application of artificial intelligence technology is provided for achieving scale-up application of SACs in petrochemical process.
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Affiliation(s)
- Min Li
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Guangxun Sun
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Zhidong Wang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Xin Zhang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Jiatian Peng
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Fei Jiang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Junxi Li
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Shu Tao
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Yunqi Liu
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
| | - Yuan Pan
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, 266580, China
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5
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Lv H, Huang F, Zhang F. Upcycling Waste Plastics with a C-C Backbone by Heterogeneous Catalysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:5077-5089. [PMID: 38358312 DOI: 10.1021/acs.langmuir.3c03866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
Plastics with an inert carbon-carbon (C-C) backbone, such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC), are the most widely used types of plastic in human activities. However, many of these polymers were directly discarded in nature after use, and few were appropriately recycled. This not only threatens the natural environment but also leads to the waste of carbon resources. Conventional chemical recycling of these plastics, including pyrolysis and catalytic cracking, requires a high energy input due to the chemical inertness of C-C bonds and C-H bonds and leads to complex product distribution. In recent years, significant progress has been made in the development of catalysts and the introduction of small molecules as additional coreactants, which could potentially overcome these challenges. In this Review, we summarize and highlight catalytic strategies that address these issues in upcycling C-C backbone plastics with small molecules, particularly in heterogeneous catalysis. We believe that this review will inspire the development of upcycling methods for C-C backbone plastics using small molecules and heterogeneous catalysis.
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Affiliation(s)
- Huidong Lv
- National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, Chengdu 610064, Sichuan People's Republic of China
| | - Fei Huang
- National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, Chengdu 610064, Sichuan People's Republic of China
| | - Fan Zhang
- National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, Chengdu 610064, Sichuan People's Republic of China
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Zhao B, Tan H, Yang J, Zhang X, Yu Z, Sun H, Wei J, Zhao X, Zhang Y, Chen L, Yang D, Deng J, Fu Y, Huang Z, Jiao N. Catalytic conversion of mixed polyolefins under mild atmospheric pressure. Innovation (N Y) 2024; 5:100586. [PMID: 38414518 PMCID: PMC10897897 DOI: 10.1016/j.xinn.2024.100586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 01/31/2024] [Indexed: 02/29/2024] Open
Abstract
The chemical recycling of polyolefin presents a considerable challenge, especially as upcycling methods struggle with the reality that plastic wastes typically consist of mixtures of polyethylene (PE), polystyrene (PS), and polypropylene (PP). We report a catalytic aerobic oxidative approach for polyolefins upcycling with the corresponding carboxylic acids as the product. This method encompasses three key innovations. First, it operates under atmospheric pressure and mild conditions, using O2 or air as the oxidant. Second, it is compatible with high-density polyethylene, low-density polyethylene, PS, PP, and their blends. Third, it uses an economical and recoverable metal catalyst. It has been demonstrated that this approach can efficiently degrade mixed wastes of plastic bags, bottles, masks, and foam boxes.
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Affiliation(s)
- Binzhi Zhao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Hui Tan
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Jie Yang
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, University of Science and Technology of China, Hefei 230026, China
| | - Xiaohui Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Zidi Yu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Hanli Sun
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Jialiang Wei
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xinyi Zhao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yufeng Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Lili Chen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Dali Yang
- The Institute for Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Jin Deng
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, University of Science and Technology of China, Hefei 230026, China
| | - Yao Fu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM, University of Science and Technology of China, Hefei 230026, China
| | - Zheng Huang
- State Key Laboratory of Organometallic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
| | - Ning Jiao
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
- State Key Laboratory of Organometallic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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7
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He C, Liu C, Pan S, Tan Y, Guan J, Xu H. Polyurethane with β-Selenocarbonyl Structure Enabling the Combination of Plastic Degradation and Waste Upcycling. Angew Chem Int Ed Engl 2024; 63:e202317558. [PMID: 38156718 DOI: 10.1002/anie.202317558] [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: 11/17/2023] [Revised: 12/16/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
Degradable polymers offer a promising solution to mitigate global plastic pollution, but the degraded products often suffer from diminished value. Upcycling is a more sustainable approach to upgrade polymer waste into value-added products. Herein, we report a β-selenocarbonyl-containing polyurethane (SePU), which can be directly degraded under mild conditions into valuable selenium fertilizers for selenium-rich vegetable cultivation globally, enabling both plastic degradation and waste upcycling. Under oxidation condition, this polymer can be easily and selectively degraded via selenoxide elimination reaction from mixed plastic waste. The degraded product can serve as effective selenium fertilizers to increase selenium content in radish and pak choi. The SePU exhibits excellent mechanical properties. Additionally, we observed the formation of spherulites-like selenium particles within the materials during degradation for the first time. Our research offers a successful application of selenoxide elimination reaction in the field of plastic degradation for the first time, endowing plastics with both degradability and high reusable value. This strategy provides a promising solution to reduce pollution and improve economy and sustainability of plastics.
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Affiliation(s)
- Chaowei He
- Key Lab of Organic Optoelectronics & Molecular Engineering and Laboratory of Flexible Electronics Technology, Department of Chemistry, Tsinghua University, 100084, Beijing, China
| | - Cheng Liu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, Zhejiang, China
| | - Shuojiong Pan
- Key Lab of Organic Optoelectronics & Molecular Engineering and Laboratory of Flexible Electronics Technology, Department of Chemistry, Tsinghua University, 100084, Beijing, China
| | - Yizheng Tan
- Key Lab of Organic Optoelectronics & Molecular Engineering and Laboratory of Flexible Electronics Technology, Department of Chemistry, Tsinghua University, 100084, Beijing, China
| | - Jun Guan
- Key Lab of Organic Optoelectronics & Molecular Engineering and Laboratory of Flexible Electronics Technology, Department of Chemistry, Tsinghua University, 100084, Beijing, China
| | - Huaping Xu
- Key Lab of Organic Optoelectronics & Molecular Engineering and Laboratory of Flexible Electronics Technology, Department of Chemistry, Tsinghua University, 100084, Beijing, China
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8
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Vialon T, Sun H, Formon GJM, Galanopoulo P, Guibert C, Averseng F, Rager MN, Percot A, Guillaneuf Y, Van Zee NJ, Nicolaÿ R. Upcycling Polyolefin Blends into High-Performance Materials by Exploiting Azidotriazine Chemistry Using Reactive Extrusion. J Am Chem Soc 2024; 146:2673-2684. [PMID: 38238037 DOI: 10.1021/jacs.3c12303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
The revalorization of incompatible polymer blends is a key obstacle in realizing a circular economy in the plastics industry. Polyolefin waste is particularly challenging because it is difficult to sort into its constituent components. Untreated blends of polyethylene and polypropylene typically exhibit poor mechanical properties that are suitable only for low-value applications. Herein, we disclose a simple azidotriazine-based grafting agent that enables polyolefin blends to be directly upcycled into high-performance materials by using reactive extrusion at industrially relevant processing temperatures. Based on a series of model experiments, the azidotriazine thermally decomposes to form a triplet nitrene species, which subsequently undergoes a complex mixture of grafting, oligomerization, and cross-linking reactions; strikingly, the oligomerization and cross-linking reactions proceed through the formation of nitrogen-nitrogen bonds. When applied to polyolefin blends during reactive extrusion, this combination of reactions leads to the generation of amorphous, phase-separated nanostructures that tend to exist at polymer-polymer interfaces. These nanostructures act as multivalent cross-linkers that reinforce the resulting material, leading to dramatically improved ductility compared with the untreated blends, along with high dimensional stability at high temperatures and excellent mechanical recyclability. We propose that this unique behavior is derived from the thermomechanically activated reversibility of the nitrogen-nitrogen bonds that make up the cross-linking structures. Finally, the scope of this chemistry is demonstrated by applying it to ternary polyolefin blends as well as postconsumer polyolefin feedstocks.
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Affiliation(s)
- Thomas Vialon
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
| | - Huidi Sun
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
| | - Georges J M Formon
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
| | - Paul Galanopoulo
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
| | - Clément Guibert
- Laboratoire de Réactivité de Surface, UMR 7197, Sorbonne Université, CNRS, 75005 Paris, France
| | - Frédéric Averseng
- Laboratoire de Réactivité de Surface, UMR 7197, Sorbonne Université, CNRS, 75005 Paris, France
| | - Marie-Noelle Rager
- NMR Facility, Chimie ParisTech, Université PSL, CNRS, 75005Paris ,France
| | - Aline Percot
- MONARIS, UMR 8233, Sorbonne Université, CNRS, 75005Paris ,France
| | - Yohann Guillaneuf
- Institut de Chimie Radicalaire UMR 7273,Aix-Marseille Université, CNRS, 13397Marseille ,France
| | - Nathan J Van Zee
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
| | - Renaud Nicolaÿ
- Chimie Moléculaire, Macromoléculaire, Matériaux, ESPCI Paris, Université PSL, CNRS, 75005Paris ,France
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9
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Ran H, Zhang S, Ni W, Jing Y. Precise activation of C-C bonds for recycling and upcycling of plastics. Chem Sci 2024; 15:795-831. [PMID: 38239692 PMCID: PMC10793209 DOI: 10.1039/d3sc05701a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/07/2023] [Indexed: 01/22/2024] Open
Abstract
The rapid accumulation of plastic waste has led to a severe environmental crisis and a noticeable imbalance between manufacturing and recycling. Fortunately, chemical upgradation of plastic waste holds substantial promise for addressing these challenges posed by white pollution. During plastic upcycling and recycling, the key challenge is to activate and cleave the inert C-C bonds in plastic waste. Therefore, this perspective delves deeper into the upcycling and recycling of polyolefins from the angle of C-C activation-cleavage. We illustrate the importance of C-C bond activation in polyolefin depolymerization and integrate molecular-level catalysis, active site modulation, reaction networks and mechanisms to achieve precise activation-cleavage of C-C bonds. Notably, we draw potential inspiration from the accumulated wisdom of related fields, such as C-C bond activation in lignin chemistry, alkane dehydrogenation chemistry, C-Cl bond activation in CVOC removal, and C-H bond activation, to influence the landscape of plastic degradation through cross-disciplinary perspectives. Consequently, this perspective offers better insights into existing catalytic technologies and unveils new prospects for future advancements in recycling and upcycling of plastic.
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Affiliation(s)
- Hongshun Ran
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China
- Institute for the Environment and Health, Nanjing University Suzhou Campus Suzhou 215163 China
| | - Shuo Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China
- Institute for the Environment and Health, Nanjing University Suzhou Campus Suzhou 215163 China
| | - Wenyi Ni
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China
- Institute for the Environment and Health, Nanjing University Suzhou Campus Suzhou 215163 China
| | - Yaxuan Jing
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China
- Institute for the Environment and Health, Nanjing University Suzhou Campus Suzhou 215163 China
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10
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Johnson AM, Johnson JA. Thermally Robust yet Deconstructable and Chemically Recyclable High-Density Polyethylene (HDPE)-Like Materials Based on Si-O Bonds. Angew Chem Int Ed Engl 2023:e202315085. [PMID: 37903133 DOI: 10.1002/anie.202315085] [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: 10/07/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/01/2023]
Abstract
Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into the backbone of PE, it is possible to produce chemically deconstructable PE derivatives; to date, however, such designs have primarily relied on carbonyl- and olefin-related functional groups. Bifunctional silyl ethers (BSEs; SiR2 (OR'2 )) could expand the functional scope of PE mimics as they possess strong Si-O bonds and facile chemical tunability. Here, we report BSE-containing high-density polyethylene (HDPE)-like materials synthesized through a one-pot catalytic ring-opening metathesis polymerization (ROMP) and hydrogenation sequence. The crystallinity of these materials can be adjusted by varying the BSE concentration or the steric bulk of the Si-substituents, providing handles to control thermomechanical properties. Two methods for chemical recycling of HDPE mimics are introduced, including a circular approach that leverages acid-catalyzed Si-O bond exchange with 1-propanol. Additionally, despite the fact that the starting HDPE mimics were synthesized by chain-growth polymerization (ROMP), we show that it is possible to recover the molar mass and dispersity of recycled HDPE products using step-growth Si-O bond formation or exchange, generating high molecular weight recycled HDPE products with mechanical properties similar to commercial HDPE.
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Affiliation(s)
- Alayna M Johnson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Jeremiah A Johnson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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