1
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O'Neill RT, Boulatov R. Experimental quantitation of molecular conditions responsible for flow-induced polymer mechanochemistry. Nat Chem 2023; 15:1214-1223. [PMID: 37430105 DOI: 10.1038/s41557-023-01266-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 06/05/2023] [Indexed: 07/12/2023]
Abstract
Fragmentation of macromolecular solutes in rapid flows is of considerable fundamental and practical importance. The sequence of molecular events preceding chain fracture is poorly understood, because such events cannot be visualized directly but must be inferred from changes in the bulk composition of the flowing solution. Here we describe how analysis of same-chain competition between fracture of a polystyrene chain and isomerization of a chromophore embedded in its backbone yields detailed characterization of the distribution of molecular geometries of mechanochemically reacting chains in sonicated solutions. In our experiments the overstretched (mechanically loaded) chain segment grew and drifted along the backbone on the same timescale as, and in competition with, the mechanochemical reactions. Consequently, only <30% of the backbone of a fragmenting chain is overstretched, with both the maximum force and the maximum reaction probabilities located away from the chain centre. We argue that quantifying intrachain competition is likely to be mechanistically informative for any flow fast enough to fracture polymer chains.
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Affiliation(s)
| | - Roman Boulatov
- Department of Chemistry, University of Liverpool, Liverpool, UK.
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2
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Huo Z, Skala SJ, Falck LR, Laaser JE, Statt A. Computational Study of Mechanochemical Activation in Nanostructured Triblock Copolymers. ACS POLYMERS AU 2022; 2:467-477. [PMID: 36536889 PMCID: PMC9756960 DOI: 10.1021/acspolymersau.2c00031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 06/17/2023]
Abstract
Force-driven chemical reactions have emerged as an attractive platform for diverse applications in polymeric materials. However, the microscopic chain conformations and topologies necessary for efficiently transducing macroscopic forces to the molecular scale are not well-understood. In this work, we use a coarse-grained model to investigate the impact of network-like topologies on mechanochemical activation in self-assembled triblock copolymers. We find that mechanochemical activation during tensile deformation depends strongly on both the polymer composition and chain conformation in these materials. Activation primarily occurs in the tie chains connecting different glassy domains and in loop chains that are hooked onto each other by physical entanglements. Activation also requires a higher stress in materials having a higher glassy block content. Overall, the lamellar samples show the highest percent activation at high stress. In contrast, at low stress, the spherical morphology, which has the lowest glassy fraction, shows the highest activation. Additionally, we observe a spatial pattern of activation, which appears to be tied to distortion of the self-assembled morphology. Higher activation is observed in the tips of the chevrons formed during deformation of lamellar samples as well as in the centers between the cylinders in the cylindrical morphology. Our work shows that changes in the network-like topology in different morphologies significantly impact mechanochemical activation efficiencies in these materials, suggesting that this area will be a fruitful avenue for further experimental research.
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Affiliation(s)
- Zijian Huo
- Department
of Chemistry, University of Pittsburgh, 219 Parkman Ave., Pittsburgh, Pennsylvania 15260, United States
| | - Stephen J Skala
- Materials
Science and Engineering, Grainger College of Engineering, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - Lavinia R Falck
- Department
of Chemistry, University of Pittsburgh, 219 Parkman Ave., Pittsburgh, Pennsylvania 15260, United States
| | - Jennifer E Laaser
- Department
of Chemistry, University of Pittsburgh, 219 Parkman Ave., Pittsburgh, Pennsylvania 15260, United States
| | - Antonia Statt
- Materials
Science and Engineering, Grainger College of Engineering, University of Illinois, Urbana−Champaign, Illinois 61801, United States
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3
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Xuan M, Schumacher C, Bolm C, Göstl R, Herrmann A. The Mechanochemical Synthesis and Activation of Carbon-Rich π-Conjugated Materials. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105497. [PMID: 35048569 PMCID: PMC9259731 DOI: 10.1002/advs.202105497] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/21/2021] [Indexed: 05/14/2023]
Abstract
Mechanochemistry uses mechanical force to break, form, and manipulate chemical bonds to achieve functional transformations and syntheses. Over the last years, many innovative applications of mechanochemistry have been developed. Specifically for the synthesis and activation of carbon-rich π-conjugated materials, mechanochemistry offers reaction pathways that either are inaccessible with other stimuli, such as light and heat, or improve reaction yields, energy consumption, and substrate scope. Therefore, this review summarizes the recent advances in this research field combining the viewpoints of polymer and trituration mechanochemistry. The highlighted mechanochemical transformations include π-conjugated materials as optical force probes, the force-induced release of small dye molecules, and the mechanochemical synthesis of polyacetylene, carbon allotropes, and other π-conjugated materials.
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Affiliation(s)
- Mingjun Xuan
- DWI – Leibniz Institute for Interactive MaterialsForckenbeckstr. 50Aachen52056Germany
- Institute of Technical and Macromolecular ChemistryRWTH Aachen UniversityWorringerweg 1Aachen52074Germany
| | - Christian Schumacher
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 1Aachen52074Germany
| | - Carsten Bolm
- Institute of Organic ChemistryRWTH Aachen UniversityLandoltweg 1Aachen52074Germany
| | - Robert Göstl
- DWI – Leibniz Institute for Interactive MaterialsForckenbeckstr. 50Aachen52056Germany
| | - Andreas Herrmann
- DWI – Leibniz Institute for Interactive MaterialsForckenbeckstr. 50Aachen52056Germany
- Institute of Technical and Macromolecular ChemistryRWTH Aachen UniversityWorringerweg 1Aachen52074Germany
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4
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Küng R, Göstl R, Schmidt BM. Release of Molecular Cargo from Polymer Systems by Mechanochemistry. Chemistry 2022; 28:e202103860. [PMID: 34878679 PMCID: PMC9306765 DOI: 10.1002/chem.202103860] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Indexed: 11/15/2022]
Abstract
The design and manipulation of (multi)functional materials at the nanoscale holds the promise of fuelling tomorrow's major technological advances. In the realm of macromolecular nanosystems, the incorporation of force-responsive groups, so called mechanophores, has resulted in unprecedented access to responsive behaviours and enabled sophisticated functions of the resulting structures and advanced materials. Among the diverse force-activated motifs, the on-demand release or activation of compounds, such as catalysts, drugs, or monomers for self-healing, are sought-after since they enable triggering pristine small molecule function from macromolecular frameworks. Here, we highlight examples of molecular cargo release systems from polymer-based architectures in solution by means of sonochemical activation by ultrasound (ultrasound-induced mechanochemistry). Important design concepts of these advanced materials are discussed, as well as their syntheses and applications.
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Affiliation(s)
- Robin Küng
- Institut für Organische Chemie und Makromolekulare ChemieHeinrich-Heine-Universität DüsseldorfUniversitätsstraße 140225DüsseldorfGermany
| | - Robert Göstl
- DWI – Leibniz Institute for Interactive MaterialsForckenbeckstr. 5052056AachenGermany
| | - Bernd M. Schmidt
- Institut für Organische Chemie und Makromolekulare ChemieHeinrich-Heine-Universität DüsseldorfUniversitätsstraße 140225DüsseldorfGermany
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5
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Bowser BH, Wang S, Kouznetsova TB, Beech HK, Olsen BD, Rubinstein M, Craig SL. Single-Event Spectroscopy and Unravelling Kinetics of Covalent Domains Based on Cyclobutane Mechanophores. J Am Chem Soc 2021; 143:5269-5276. [PMID: 33783187 DOI: 10.1021/jacs.1c02149] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mechanochemical reactions that lead to an increase in polymer contour length have the potential to serve as covalent synthetic mimics of the mechanical unfolding of noncovalent "stored length" domains in structural proteins. Here we report the force-dependent kinetics of stored length release in a family of covalent domain polymers based on cis-1,2-substituted cyclobutane mechanophores. The stored length is determined by the size (n) of a fused ring in an [n.2.0] bicyclic architecture, and it can be made sufficiently large (>3 nm per event) that individual unravelling events are resolved in both constant-velocity and constant-force single-molecule force spectroscopy (SMFS) experiments. Replacing a methylene in the pulling attachment with a phenyl group drops the force necessary to achieve rate constants of 1 s-1 from ca. 1970 pN (dialkyl handles) to 630 pN (diaryl handles), and the substituent effect is attributed to a combination of electronic stabilization and mechanical leverage effects. In contrast, the kinetics are negligibly perturbed by changes in the amount of stored length. The independent control of unravelling force and extension holds promise as a probe of molecular behavior in polymer networks and for optimizing the behaviors of materials made from covalent domain polymers.
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Affiliation(s)
- Brandon H Bowser
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Shu Wang
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Tatiana B Kouznetsova
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Haley K Beech
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bradley D Olsen
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Michael Rubinstein
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.,Departments of Physics, Mechanical Engineering and Materials Science, and Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States.,World Premier Institute for Chemical Reaction Design and Discovery, Hokkaido University, Sapporo, Japan
| | - Stephen L Craig
- NSF Center for the Chemistry of Molecularly Optimized Networks, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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6
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Sha Y, Zhang H, Zhou Z, Luo Z. Stress-responsive properties of metallocenes in metallopolymers. Polym Chem 2021. [DOI: 10.1039/d1py00311a] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review article combines the field of metallopolymers and stress-responsiveness on a molecular level, namely, metallocenes, as emerging stress-responsive building blocks for materials.
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Affiliation(s)
- Ye Sha
- College of Science
- Nanjing Forestry University
- Nanjing
- PR China
| | - Hao Zhang
- College of Science
- Nanjing Forestry University
- Nanjing
- PR China
| | - Zhou Zhou
- College of Science
- Nanjing Forestry University
- Nanjing
- PR China
| | - Zhenyang Luo
- College of Science
- Nanjing Forestry University
- Nanjing
- PR China
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7
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Tian Y, Cao X, Li X, Zhang H, Sun CL, Xu Y, Weng W, Zhang W, Boulatov R. A Polymer with Mechanochemically Active Hidden Length. J Am Chem Soc 2020; 142:18687-18697. [PMID: 33064473 PMCID: PMC7596784 DOI: 10.1021/jacs.0c09220] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Incorporating hidden length into polymer chains can improve their mechanical properties, because release of the hidden length under mechanical loads enables localized strain relief without chain fracture. To date, the design of hidden length has focused primarily on the choice of the sacrificial bonds holding the hidden length together. Here we demonstrate the advantages of adding mechanochemical reactivity to hidden length itself, using a new mechanophore that integrates (Z)-2,3-diphenylcyclobutene-1,4-dicarboxylate, with hitherto unknown mechanochemistry, into macrocyclic cinnamate dimers. Stretching a polymer of this mechanophore more than doubles the chain contour length without fracture. DFT calculations indicate that the sequential dissociation of the dimer, followed by cyclobutene isomerization at higher forces yields a chain fracture energy 11 times that of a simple polyester of the same initial contour length and preserves high energy-dissipating capacity up to ∼3 nN. In sonicated solutions cyclobutene isomerizes to two distinct products by competing reaction paths, validating the computed mechanochemical mechanism and suggesting an experimental approach to quantifying the distribution of single-chain forces under diverse loading scenarios.
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Affiliation(s)
- Yancong Tian
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K
| | - Xiaodong Cao
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Xun Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, People's Republic of China
| | - Huan Zhang
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Cai-Li Sun
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K
| | - Yuanze Xu
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Wengui Weng
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
| | - Wenke Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin 130012, People's Republic of China
| | - Roman Boulatov
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, U.K
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8
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Vollmer I, Jenks MJF, Roelands MCP, White RJ, van Harmelen T, de Wild P, van der Laan GP, Meirer F, Keurentjes JTF, Weckhuysen BM. Beyond Mechanical Recycling: Giving New Life to Plastic Waste. Angew Chem Int Ed Engl 2020; 59:15402-15423. [PMID: 32160372 PMCID: PMC7497176 DOI: 10.1002/anie.201915651] [Citation(s) in RCA: 413] [Impact Index Per Article: 103.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/23/2020] [Indexed: 11/30/2022]
Abstract
Increasing the stream of recycled plastic necessitates an approach beyond the traditional recycling via melting and re-extrusion. Various chemical recycling processes have great potential to enhance recycling rates. In this Review, a summary of the various chemical recycling routes and assessment via life-cycle analysis is complemented by an extensive list of processes developed by companies active in chemical recycling. We show that each of the currently available processes is applicable for specific plastic waste streams. Thus, only a combination of different technologies can address the plastic waste problem. Research should focus on more realistic, more contaminated and mixed waste streams, while collection and sorting infrastructure will need to be improved, that is, by stricter regulation. This Review aims to inspire both science and innovation for the production of higher value and quality products from plastic recycling suitable for reuse or valorization to create the necessary economic and environmental push for a circular economy.
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Affiliation(s)
- Ina Vollmer
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterials Science, Utrecht UniversityUniversiteitsweg 993584CGUtrechtThe Netherlands
| | - Michael J. F. Jenks
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterials Science, Utrecht UniversityUniversiteitsweg 993584CGUtrechtThe Netherlands
| | - Mark C. P. Roelands
- The Netherlands Organisation for Applied Scientific Research (TNO)DelftThe Netherlands
| | - Robin J. White
- The Netherlands Organisation for Applied Scientific Research (TNO)Materials Solutions DepartmentEindhovenThe Netherlands
| | - Toon van Harmelen
- The Netherlands Organisation for Applied Scientific Research (TNO)Climate, Air & Sustainability DepartmentUtrechtThe Netherlands
| | - Paul de Wild
- Energieonderzoek Centrum Nederland (ECN)- part of TNO, Biomass & Energy EfficiencyPettenThe Netherlands
| | - Gerard P. van der Laan
- The Netherlands Organisation for Applied Scientific Research (TNO)Climate, Air & Sustainability DepartmentUtrechtThe Netherlands
| | - Florian Meirer
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterials Science, Utrecht UniversityUniversiteitsweg 993584CGUtrechtThe Netherlands
| | | | - Bert M. Weckhuysen
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterials Science, Utrecht UniversityUniversiteitsweg 993584CGUtrechtThe Netherlands
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9
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Vollmer I, Jenks MJF, Roelands MCP, White RJ, Harmelen T, Wild P, Laan GP, Meirer F, Keurentjes JTF, Weckhuysen BM. Die nächste Generation des Recyclings – neues Leben für Kunststoffmüll. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915651] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ina Vollmer
- Inorganic Chemistry and Catalysis Debye Institute for Nanomaterials Science Utrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
| | - Michael J. F. Jenks
- Inorganic Chemistry and Catalysis Debye Institute for Nanomaterials Science Utrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
| | - Mark C. P. Roelands
- The Netherlands Organisation for Applied Scientific Research (TNO) Delft Niederlande
| | - Robin J. White
- The Netherlands Organisation for Applied Scientific Research (TNO) Materials Solutions Department Eindhoven Niederlande
| | - Toon Harmelen
- The Netherlands Organisation for Applied Scientific Research (TNO) Climate, Air & Sustainability Department Utrecht Niederlande
| | - Paul Wild
- Energieonderzoek Centrum Nederland (ECN) –, part of TNO, Biomass & Energy Efficiency Petten Niederlande
| | - Gerard P. Laan
- The Netherlands Organisation for Applied Scientific Research (TNO) Climate, Air & Sustainability Department Utrecht Niederlande
| | - Florian Meirer
- Inorganic Chemistry and Catalysis Debye Institute for Nanomaterials Science Utrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
| | | | - Bert M. Weckhuysen
- Inorganic Chemistry and Catalysis Debye Institute for Nanomaterials Science Utrecht University Universiteitsweg 99 3584 CG Utrecht Niederlande
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10
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11
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Karman M, Verde-Sesto E, Weder C. Mechanochemical Activation of Polymer-Embedded Photoluminescent Benzoxazole Moieties. ACS Macro Lett 2018; 7:1028-1033. [PMID: 35650956 DOI: 10.1021/acsmacrolett.8b00520] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Despite an increasing number of studies that have investigated mechanochemical effects in polymers, the number of polymers whose fluorescence characteristics change upon exposure to mechanical stress is still limited. We here report the investigation of a mechanofluorophore based on an aliphatic ester of 2-(2'-hydroxyphenyl)benzoxazole. The free benzoxazole displays green photoluminescence, which is associated with an excited state intramolecular proton transfer (ESIPT) process, whereas aliphatic esters of this compound emit blue light. When poly(methyl acrylate) containing an esterified benzoxazole mechanophore at the center of each chain molecule was exposed to ultrasound, a significant reduction of the molecular weight and pronounced changes of the photoluminescence emission and UV-vis absorption spectra were observed. The optical changes and the fact that the time-traces for molecular weight decrease and formation of the ESIPT capable species mirror each other indicate that the mechanophore is preferentially cleaved upon sonication and that such cleavage restores the 2-(2'-hydroxyphenyl)benzoxazole motif. The concept of mechanical activation of ester-protected ESIPT dyes, and more broadly of other hydroxyl group carrying fluorophores that change their emission properties upon ester formation and cleavage, should be general and allow access to a range of other mechanofluorophores.
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Affiliation(s)
- Marc Karman
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Ester Verde-Sesto
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
- POLYMAT, University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastián, Spain
| | - Christoph Weder
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
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12
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Polymer Mechanochemistry: A New Frontier for Physical Organic Chemistry. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2018. [DOI: 10.1016/bs.apoc.2018.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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13
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Zhang H, Li X, Lin Y, Gao F, Tang Z, Su P, Zhang W, Xu Y, Weng W, Boulatov R. Multi-modal mechanophores based on cinnamate dimers. Nat Commun 2017; 8:1147. [PMID: 29079772 PMCID: PMC5660084 DOI: 10.1038/s41467-017-01412-8] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 09/15/2017] [Indexed: 01/06/2023] Open
Abstract
Mechanochemistry offers exciting opportunities for molecular-level engineering of stress-responsive properties of polymers. Reactive sites, sometimes called mechanophores, have been reported to increase the material toughness, to make the material mechanochromic or optically healable. Here we show that macrocyclic cinnamate dimers combine these productive stress-responsive modes. The highly thermally stable dimers dissociate on the sub-second timescale when subject to a stretching force of 1-2 nN (depending on isomer). Stretching a polymer of the dimers above this force more than doubles its contour length and increases the strain energy that the chain absorbs before fragmenting by at least 600 kcal per mole of monomer. The dissociation produces a chromophore and dimers are reformed upon irradiation, thus allowing optical healing of mechanically degraded parts of the material. The mechanochemical kinetics, single-chain extensibility, toughness and potentially optical properties of the dissociation products are tunable by synthetic modifications.
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Affiliation(s)
- Huan Zhang
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Xun Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
| | - Yangju Lin
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Fei Gao
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Zhen Tang
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Peifeng Su
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Wenke Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China.
| | - Yuanze Xu
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China
| | - Wengui Weng
- Department of Chemistry, College of Chemistry and Engineering, Xiamen University, Xiamen, Fujian, 361005, China.
| | - Roman Boulatov
- Department of Chemistry, University of Liverpool, Donnan Lab, G31, Crown St., Liverpool, L69 7ZD GB, UK.
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14
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Affiliation(s)
- Costantino Creton
- Laboratoire
de Sciences et Ingénierie de la Matière Molle, CNRS,
ESPCI Paris, PSL Research University, 10 rue Vauquelin, 75005 Paris, France
- Laboratoire
Sciences et Ingénierie de la Matière Molle, Université Pierre et Marie Curie, Sorbonne-Universités, 10 rue Vauquelin, 75005 Paris, France
- Global
Station for Soft Matter, Global Institution for Collaborative Research
and Education, Hokkaido University, Sapporo, Japan
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