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Zhu G, Zhang Q, Yu T, Chen J, Hu R, Yang G, Zeng Y, Li Y. Multiple Force-Triggered Downconverted and Upconverted Emission in Polymers Containing Diels-Alder Adducts. Chem Asian J 2024; 19:e202301147. [PMID: 38334040 DOI: 10.1002/asia.202301147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/04/2024] [Accepted: 02/05/2024] [Indexed: 02/10/2024]
Abstract
Fluorescent mechanophores can indicate the deformation or damage in polymers. The development of mechanophores with multi-triggered response is of great interest. Herein, Diels-Alder (DA) adducts are incorporated into linear poly(methyl acrylate) PMA-BA and network poly(hexyl methacrylate) (PHMA) as mechanophores to detect the stress caused by ultrasound, freezing, and compression. The DA mechanophores undergo retro-DA reaction to release 9-styrylanthracene chromophore upon applying force, resulting in cyan fluorescence. The dissociation ratio of the DA mechanophore after pulsed ultrasonication of PMA-BA solution for 240 minutes is estimated to be 52 % by absorption spectra and 1H NMR. Additionally, the rate constant of mechanical cleavage is calculated to be 1.2×10-4 min-1⋅kDa-1 with the decrease in molecular weight from 69 to 22 kDa measured by gel permeation chromatography. Freezing of PHMA gels as well as compression of PHMA bulk samples turn-on the DA mechanophores, revealing the microscale fracture. Photon upconversion responses toward various force stimuli are also achieved in both polymer solutions and bulk samples by doping platinum octaethylporphyrin (PtOEP) or palladium meso-tetraphenyltetrabenzoporphyrin (PdTPTBP) sensitizers with multiple excitation wavelengths.
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Affiliation(s)
- Guohua Zhu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Qiaoyu Zhang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Tianjun Yu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jinping Chen
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Rui Hu
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Guoqiang Yang
- Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Yi Zeng
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
| | - Yi Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Science, Beijing, 100049, China
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2
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Abstract
Mechanophores (mechanosensitive molecules) have been instrumental in the development of various force-controlled release systems. However, the release of functional organic molecules is often the consequence of a secondary (nonmechanical) process triggered by an initial bond scission. Here we present a new mechanophore, built around an oxanorbornane-triazoline core, that is able to release a furan molecule following a force-promoted double retro-[4+2][3+2] cycloaddition. We explored this unprecedented transformation experimentally (sonication) and computationally (DFT, CoGEF) and found that the observed reactivity is controlled by the geometry of the adduct, as this reaction pathway is only accessible to the endo-exo-cis isomer. These results further demonstrate the unique reactivity of molecules under tension and offer a new mechanism for the force-controlled release of small molecules.
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Affiliation(s)
- Kamil Suwada
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Alice Weng Ieong
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Hei Lok Herman Lo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United
Kingdom
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3
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Tse YC, Au-Yeung HY. Catenane and Rotaxane Synthesis from Cucurbit[6]uril-Mediated Azide-Alkyne Cycloaddition. Chem Asian J 2023; 18:e202300290. [PMID: 37460745 DOI: 10.1002/asia.202300290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/29/2023] [Indexed: 08/01/2023]
Abstract
The chemistry of mechanically interlocked molecules (MIMs) such as catenane and rotaxane is full of new opportunities for the presence of a mechanical bond, and the efficient synthesis of these molecules is therefore of fundamental importance in realizing their unique properties and functions. While many different types of preorganizing interactions and covalent bond formation strategies have been exploited in MIMs synthesis, the use of cucurbit[6]uril (CB[6]) in simultaneously templating macrocycle interlocking and catalyzing the covalent formation of the interlocked components is particularly advantageous in accessing high-order catenanes and rotaxanes. In this review, catenane and rotaxane obtained from CB[6]-catalyzed azide-alkyne cycloaddition will be discussed, with special emphasis on the synthetic strategies employed for obtaining complex [n]rotaxanes and [n]catenanes, as well as their properties and functions.
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Affiliation(s)
- Yuen Cheong Tse
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - Ho Yu Au-Yeung
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
- State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
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4
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Cardosa-Gutierrez M, De Bo G, Duwez AS, Remacle F. Bond breaking of furan-maleimide adducts via a diradical sequential mechanism under an external mechanical force. Chem Sci 2023; 14:1263-1271. [PMID: 36756317 PMCID: PMC9891376 DOI: 10.1039/d2sc05051j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 12/27/2022] [Indexed: 01/06/2023] Open
Abstract
Substituted furan-maleimide Diels-Alder adducts are bound by dynamic covalent bonds that make them particularly attractive mechanophores. Thermally activated [4 + 2] retro-Diels-Alder (DA) reactions predominantly proceed via a concerted mechanism in the ground electronic state. We show that an asymmetric mechanical force along the anchoring bonds in both the endo and exo isomers of proximal dimethyl furan-maleimide adducts favors a sequential pathway. The switching from a concerted to a sequential mechanism occurs at external forces of ≈1 nN. The first bond rupture occurs for a projection of the pulling force on the scissile bond at ≈4.3 nN for the exo adduct and ≈3.8 nN for the endo one. The reaction is inhibited for external forces up to ≈3.4 nN for the endo adduct and 3.6 nN for the exo one after which it is activated. In the activated region, at 4 nN, the rupture rate of the first bond for the endo adduct is computed to be ≈3 orders of magnitude larger than for the exo one in qualitative agreement with recent sonication experiments [Z. Wang and S. L. Craig, Chem. Commun., 2019, 55, 12263-12266]. In the intermediate region of the path between the rupture of the first and the second bond, the lowest singlet state exhibits a diradical character for both adducts and is close in energy to a diradical triplet state. The computed values of spin-orbit coupling along the path are too small for inducing intersystem crossings. These findings open the way for the rational design of DA mechanophores for polymer science and photochemistry.
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Affiliation(s)
| | - Guillaume De Bo
- Department of Chemistry, University of ManchesterManchesterM13 9PLUK
| | - Anne-Sophie Duwez
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
| | - Francoise Remacle
- UR Molecular Systems, Department of Chemistry, University of Liège 4000 Liège Belgium
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5
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Luo SM, Barber RW, Overholts AC, Robb MJ. Competitive Activation Experiments Reveal Significantly Different Mechanochemical Reactivity of Furan–Maleimide and Anthracene–Maleimide Mechanophores. ACS Polym Au 2022; 3:202-208. [PMID: 37065719 PMCID: PMC10103189 DOI: 10.1021/acspolymersau.2c00047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/23/2022]
Abstract
During the past two decades, our understanding of mechanochemical reactivity has advanced considerably. Nevertheless, an incomplete knowledge of structure-activity relationships and the principles that govern mechanochemical transformations limits molecular design. The experimental development of mechanophores has thus benefited from simple computational tools like CoGEF, from which quantitative metrics like rupture force can be extracted to estimate reactivity. Furan-maleimide (FM) and anthracene-maleimide (AM) Diels-Alder adducts are widely studied mechanophores that undergo retro-Diels-Alder reactions upon mechanical activation in polymers. Despite possessing significantly different thermal stability, similar rupture forces predicted by CoGEF calculations suggest that these compounds exhibit similar mechanochemical reactivity. Here, we directly probe the relative mechanochemical reactivity of FM and AM adducts through competitive activation experiments. Ultrasound-induced mechanochemical activation of bis-adduct mechanophores comprising covalently tethered FM and AM subunits reveals pronounced selectivity-as high as ∼13:1-for reaction of the FM adduct compared to the AM adduct. Computational models provide insight into the greater reactivity of the FM mechanophore, indicating a more efficient mechanochemical coupling for the FM adduct compared to the AM adduct. The methodology employed here to directly interrogate the relative reactivity of two different mechanophores using a tethered bis-adduct configuration may be useful for other systems where more common sonication-based approaches are limited by poor sensitivity.
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Affiliation(s)
- Stella M. Luo
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Ross W. Barber
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Anna C. Overholts
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Maxwell J. Robb
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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6
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Wu M, Li Y, Yuan W, De Bo G, Cao Y, Chen Y. Cooperative and Geometry-Dependent Mechanochromic Reactivity through Aromatic Fusion of Two Rhodamines in Polymers. J Am Chem Soc 2022; 144:17120-17128. [PMID: 36070612 DOI: 10.1021/jacs.2c07015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The unique topological features of Piezo proteins underlie the lever-like cellular mechanotransduction mechanism. This knowledge inspires us to seek topological/geometric control of mechanochromophores with unprecedentedly amplified, synergistic changes in polymers to serve as ideal stress probes. Here, by judicious placement of two spirolactam rings into aminobenzopyranoxanthene, a series of stereo- and regio-isomeric rhodamine-like mechanophores are developed. With two labile bonds closely coupled into one rigidified scaffold, these π-fused bis-mechanophores enable mechanochromic polymers, featuring cooperative bond scission, low rupture force (lower than rhodamine), and geometry-controlled ring-opening reactivity. Sonication, single-molecule force spectroscopy experiments, and density functional theory calculations provide insight into the force-color relationship and rationalize how the difference in reactivity of the four isomeric mechanophores is affected by their molecular geometry and thermodynamic equilibrium. Our strategy based on the aromatic fusion of bis-mechanophore promises a modular approach to isomeric mechanophores for cooperative bond scission. Also, important insights into internal and external factors governing tandem mechanochemical reactions are gained.
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Affiliation(s)
- Mengjiao Wu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, P. R. China.,Department of Chemistry, Tianjin University, Tianjin 300354, P. R. China
| | - Yiran Li
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, P. R. China
| | - Wei Yuan
- Department of Chemistry, Tianjin University, Tianjin 300354, P. R. China
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K
| | - Yi Cao
- Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, P. R. China
| | - Yulan Chen
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, P. R. China
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7
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Wang X, Cao Y, Peng Y, Wang L, Hou W, Zhou Y, Shi Y, Huang H, Chen Y, Li Y. Concurrent and Mechanochemical Activation of Two Distinct and Latent Fluorophores via Retro-Diels-Alder Reaction of an Anthracene-Aminomaleimide Adduct. ACS Macro Lett 2022; 11:310-316. [PMID: 35575364 DOI: 10.1021/acsmacrolett.2c00036] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Generally, a typical mechanochromophore produces color change through chemical transformation into one or two identical new chromophores/fluorophores under applied mechanical force. Herein, we introduce a novel mechanophore based on an anthracene-aminomaleimide Diels-Alder (DA) adduct featuring two distinct and latent fluorophores. This nonfluorescent mechanophore undergoes retro-DA reaction upon mechanochemical activation in solution and the solid state, generating the respective anthracene and aminomaleimide fragments simultaneously, both of which are highly emissive with different fluorescent colors. In addition, the aminomaleimide fluorophore exhibits sensitive fluorescence on-off response to protic solvents or polar solvents, which enables dual-color mechanochromism from this single mechanophore.
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Affiliation(s)
- Xiaoying Wang
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yifeng Cao
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yanling Peng
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Lewen Wang
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Wangmeng Hou
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yecheng Zhou
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yi Shi
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Huahua Huang
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yongming Chen
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yuanchao Li
- School of Materials Science and Engineering, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Research Center for Functional Biomaterials Engineering and Technology Guangdong, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Sun Yat-Sen University, Guangzhou 510006, China
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8
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Truong VX, Rodrigues LL, Barner-Kowollik C. Light- and mechanic field controlled dynamic soft matter materials. Polym Chem 2022. [DOI: 10.1039/d2py00892k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A photochemical reaction system that fuses photo- and mechanochemistry into one macromolecular design for light- and mechano-reversible modification of polymer endgroups is introduced.
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Affiliation(s)
- Vinh X. Truong
- Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
| | - Leona L. Rodrigues
- Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
| | - Christopher Barner-Kowollik
- Centre for Materials Science, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
- School of Chemistry and Physics, Queensland University of Technology, 2 George Street, Brisbane, QLD 4000, Australia
- Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
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9
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Galkin KI, Sandulenko IV, Polezhaev AV. Diels–Alder Cycloadditions of Bio-Derived Furans with Maleimides as a Sustainable «Click» Approach towards Molecular, Macromolecular and Hybrid Systems. Processes (Basel) 2021; 10:30. [DOI: 10.3390/pr10010030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
This mini-review highlights the recent research trends in designing organic or organic-inorganic hybrid molecular, biomolecular and macromolecular systems employing intermolecular Diels–Alder cycloadditions of biobased, furan-containing substrates and maleimide dienophiles. The furan/maleimide Diels–Alder reaction is a well-known process that may proceed with high efficiency under non-catalytic and solvent-free conditions. Due to the simplicity, 100% atom economy and biobased nature of many furanic substrates, this type of [4+2]-cycloaddition may be recognized as a sustainable “click” approach with high potential for application in many fields, such as fine organic synthesis, bioorganic chemistry, material sciences and smart polymers development.
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10
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Abstract
In mechanochemistry, molecules under tension can react in unexpected ways. The reactivity of mechanophores (mechanosensitive molecules) can be controlled using various geometric or electronic factors. Often these factors affect the rate of mechanical activation but sometimes give rise to alternative reaction pathways. Here we show that a simple isotope substitution (H to D) leads to a reversal of selectivity in the activation of a mechanophore. Remarkably this isotope effect is not kinetic in nature but emerges from dynamic effects in which deuteration reduces the ability of the reactant to follow a post-transition-state concerted trajectory on the bifurcated force-modified potential energy surface. These results give a new insight into the reactivity of molecules under tension.
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Affiliation(s)
- Robert Nixon
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Guillaume De Bo
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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11
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Razgoniaev AO, Glasstetter LM, Kouznetsova TB, Hall KC, Horst M, Craig SL, Franz KJ. Single-Molecule Activation and Quantification of Mechanically Triggered Palladium-Carbene Bond Dissociation. J Am Chem Soc 2021; 143:1784-1789. [PMID: 33480680 DOI: 10.1021/jacs.0c13219] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Metal-complexed N-heterocyclic carbene (NHC) mechanophores are latent reactants and catalysts for a range of mechanically driven chemical responses, but mechanochemical scission of the metal-NHC bond has not been experimentally characterized. Here we report the single-molecule force spectroscopy of ligand dissociation from a pincer NHC-pyridine-NHC Pd(II) complex. The force-coupled rate constant for ligand dissociation reaches 50 s-1 at forces of approximately 930 pN. Experimental and computational observations support a dissociative, rather than associative, mechanism of ligand displacement, with rate-limiting scission of the Pd-NHC bond followed by rapid dissociation of the pyridine moiety from Pd.
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Affiliation(s)
- Anton O Razgoniaev
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Logan M Glasstetter
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Tatiana B Kouznetsova
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Kacey C Hall
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Matias Horst
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Stephen L Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Katherine J Franz
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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12
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Ayer MA, Verde-Sesto E, Liu CH, Weder C, Lattuada M, Simon YC. Modeling ultrasound-induced molecular weight decrease of polymers with multiple scissile azo-mechanophores. Polym Chem 2021. [DOI: 10.1039/d1py00420d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Selective and non-selective chain scission compete upon ultrasonic treatment of polymers with randomly distributed azo units.
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Affiliation(s)
- Mathieu A. Ayer
- Adolphe Merkle Institute
- University of Fribourg
- 1700 Fribourg
- Switzerland
| | - Ester Verde-Sesto
- Adolphe Merkle Institute
- University of Fribourg
- 1700 Fribourg
- Switzerland
- Centro de Física de Materiales (CSIC
| | - Cheyenne H. Liu
- School of Polymer Science and Engineering
- The University of Southern Mississippi
- 118 College Dr
- USA
| | - Christoph Weder
- Adolphe Merkle Institute
- University of Fribourg
- 1700 Fribourg
- Switzerland
| | - Marco Lattuada
- Adolphe Merkle Institute
- University of Fribourg
- 1700 Fribourg
- Switzerland
- Department of Chemistry
| | - Yoan C. Simon
- Adolphe Merkle Institute
- University of Fribourg
- 1700 Fribourg
- Switzerland
- School of Polymer Science and Engineering
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13
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Wu M, Guo Z, He W, Yuan W, Chen Y. Empowering self-reporting polymer blends with orthogonal optical properties responsive in a broader force range. Chem Sci 2020; 12:1245-1250. [PMID: 34163886 PMCID: PMC8179123 DOI: 10.1039/d0sc06140a] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Self-reporting polymers, which can indicate damage with perceptible optical signals in a tailored force range, are useful as stress-sensitive sensors. We demonstrate a simple approach to realize this function by embedding two distinct mechanophores - rhodamine (Rh) and bis(adamantyl)-1,2-dioxetane (Ad), in polyurethane/polylactic acid blends. The deformed blends generate red coloration and red chemiluminescence. Such a unique dual-responsive behavior was evaluated by solid-state UV-vis spectroscopy, macroscopic tensile tests with in situ RGB and light intensity analyses, which supported a stress-correlated occurrence of the ring-opening of Rh, the scission of Ad and the fluorescence resonance energy transfer process between the respective mechanochemical species. Complementarity stemming from the difference in properties and manifestations of the two mechanophores is essential. That is, the more labile Rh allows shifting the appreciable optical changes to a much lower force threshold; the transient nature and high dynamic range of mechanochemiluminescence from Ad map in real time where and when many of the covalently incorporated dioxetane bonds break; besides, the disrupted yet non-scissile structure of Rh acts as a fluorescent acceptor to effectively harvest chemiluminescence from ruptured Ad. The current strategy is thus empowering multi-functional mechano-responsive polymers with greatly improved sensitivity and resolution for multimodal stress reporting.
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Affiliation(s)
- Mengjiao Wu
- Department of Chemistry, Key Laboratory of Mechanism Theory and Equipment Design of State Ministry of Education, Tianjin University Tianjin 300354 China
| | - Zhen Guo
- Department of Chemistry, Key Laboratory of Mechanism Theory and Equipment Design of State Ministry of Education, Tianjin University Tianjin 300354 China
| | - Weiye He
- Department of Chemistry, Key Laboratory of Mechanism Theory and Equipment Design of State Ministry of Education, Tianjin University Tianjin 300354 China
| | - Wei Yuan
- Department of Chemistry, Key Laboratory of Mechanism Theory and Equipment Design of State Ministry of Education, Tianjin University Tianjin 300354 China
| | - Yulan Chen
- Department of Chemistry, Key Laboratory of Mechanism Theory and Equipment Design of State Ministry of Education, Tianjin University Tianjin 300354 China
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