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Zhao J, Li C, Sui J, Feng T, Li C, Liu L, Xue H, Zhao W, Chen X. Synthesis of tunable thickness-to-diameter ratio microcapsules via a diffusion-controlled process for temperature-responsive release. NANOSCALE 2024; 16:8495-8503. [PMID: 38591112 DOI: 10.1039/d3nr06483b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Designing microcapsules with a complicated functionalized shell to respond to an external stimulus has attracted much attention for triggered release; however, simplifying the synthesis process remains a significant challenge. Herein, we initially propose a novel, simple synthesis strategy that utilizes a mixed solvent as the organic phase to control the diffusion of common monomers during interfacial polymerization, resulting in the successful preparation of microcapsules with tunable thickness-to-diameter ratios (T/D). The morphology of microcapsules is confirmed by scanning electron microscopy. We also observe that the T/D of the designed microcapsules progressively increases as the diffusion of monomers occurs, and the glass transition temperature of microcapsules is controlled. Furthermore, microcapsule-based crosslinking agents are applied to investigate the crosslinking reaction of poly(vinyl chloride). Rotational rheometer results indicate that the microcapsules exhibit an excellent external stimulus response, precisely triggering release at the predetermined temperature. This simple approach for the preparation of microcapsules with tunable physical properties has great potential for triggered release in diverse applications.
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Affiliation(s)
- Jinshun Zhao
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China.
| | - Chun Li
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Jiayang Sui
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tong Feng
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Chonghui Li
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Lifei Liu
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Huimin Xue
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Weizhen Zhao
- Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Xuhuang Chen
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, China.
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2
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Li W, Lu X, Diamond JM, Shen C, Jiang B, Sun S, Moore JS, Sottos NR. Photo-modulated activation of organic bases enabling microencapsulation and on-demand reactivity. Nat Commun 2024; 15:2771. [PMID: 38553489 PMCID: PMC10980803 DOI: 10.1038/s41467-024-47175-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 03/22/2024] [Indexed: 04/01/2024] Open
Abstract
A method is developed for facile encapsulation of reactive organic bases with potential application for autonomous damage detection and self-healing polymers. Highly reactive chemicals such as bases and acids are challenging to encapsulate by traditional oil-water emulsion techniques due to unfavorable physical and chemical interactions. In this work, reactivity of the bases is temporarily masked with photo-removable protecting groups, and the resulting inactive payloads are encapsulated via an in situ emulsion-templated interfacial polymerization method. The encapsulated payloads are then activated to restore the organic bases via photo irradiation, either before or after being released from the core-shell carriers. The efficacy of the photo-activated capsules is demonstrated by a damage-triggered, pH-induced color change in polymeric coatings and by recovery of adhesive strength of a damaged interface. Given the wide range of potential photo-deprotection chemistries, this encapsulation scheme provides a simple but powerful method for storage and targeted delivery of a broad variety of reactive chemicals, promoting design of diverse autonomous functionalities in polymeric materials.
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Affiliation(s)
- Wenle Li
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao, Shandong, 266580, China.
| | - Xiaocun Lu
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, 13699, USA
| | - Jacob M Diamond
- Department of Materials Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Chengtian Shen
- Department of Chemistry, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Bo Jiang
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao, Shandong, 266580, China
| | - Shi Sun
- School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao, Shandong, 266580, China
| | - Jeffrey S Moore
- Department of Chemistry, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Nancy R Sottos
- Department of Materials Science and Engineering, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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3
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Liu C, Sun Z, Jiao S, Wang T, Liu Y, Meng X, Zhang B, Han L, Liu R, Liu Y, Zhou Y. Dual-Shell Microcapsules for High-Response Efficiency Self-Healing of Multi-Scale Damage in Waterborne Polymer-Cement Coatings. Polymers (Basel) 2023; 16:105. [PMID: 38201770 PMCID: PMC10781181 DOI: 10.3390/polym16010105] [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: 11/28/2023] [Revised: 12/20/2023] [Accepted: 12/26/2023] [Indexed: 01/12/2024] Open
Abstract
Waterborne polymer-cement coatings have been widely applied in building materials due to their organic solvent-free nature, low cost, and eco-friendliness. However, these coatings can easily crack during the drying process as a result of construction environment factors, compromising the barrier performance of the coating and limiting its large-scale application. In this study, a dual-shell self-healing microcapsule was developed, which can effectively heal damage on a macro scale in waterborne polymer-cement coatings. Specifically, this dual-shell self-healing microcapsule was designed with a silica gel shell and a tannic acid-cuprum (TA-Cu) double-shell structure embedded with an epoxy resin (EP) healing agent, which was successfully fabricated via a two-step in situ polymerization. This silica gel shell self-healing microcapsules can effectively load into waterborne polymer-cement coatings. As the coating dries and solidifies, the silica gel shell of the microcapsule also becomes loose and brittle due to dehydration. This improves the mechanical initiation efficiency of the microcapsules in the coating. This study provides a novel approach for the application of self-healing microcapsules in waterborne coating systems, which can significantly reduce cracking during the drying process of waterborne polymer-cement coatings and improve the service life of the coating under complex conditions.
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Affiliation(s)
- Chenyang Liu
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Zhicheng Sun
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Shouzheng Jiao
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China;
| | - Ting Wang
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Yibin Liu
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Xianyu Meng
- State Key Laboratory of Special Functional Waterproof Materials, Beijing Oriental Yuhong Waterproof Technology Co., Ltd., Beijing 100123, China; (X.M.); (B.Z.)
| | - Binbin Zhang
- State Key Laboratory of Special Functional Waterproof Materials, Beijing Oriental Yuhong Waterproof Technology Co., Ltd., Beijing 100123, China; (X.M.); (B.Z.)
| | - Lu Han
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Ruping Liu
- Beijing Engineering Research Center of Printed Electronics, Beijing Institute of Graphic Communication, Beijing 102600, China; (C.L.); (T.W.); (Y.L.); (L.H.); (R.L.)
| | - Yuanyuan Liu
- Key Laboratory of Advanced Materials of Tropical Island Resources, Ministry of Education, School of Chemistry and Chemical Engineering, Hainan University, Haikou 570228, China;
| | - Yang Zhou
- Key Laboratory of Advanced Materials of Tropical Island Resources, Ministry of Education, School of Chemistry and Chemical Engineering, Hainan University, Haikou 570228, China;
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4
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Tauber FJ, Slesarenko V. Early career scientists converse on the future of soft robotics. Front Robot AI 2023; 10:1129827. [PMID: 36909362 PMCID: PMC9994530 DOI: 10.3389/frobt.2023.1129827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 02/09/2023] [Indexed: 02/24/2023] Open
Abstract
During the recent decade, we have witnessed an extraordinary flourishing of soft robotics. Rekindled interest in soft robots is partially associated with the advances in manufacturing techniques that enable the fabrication of sophisticated multi-material robotic bodies with dimensions ranging across multiple length scales. In recent manuscripts, a reader might find peculiar-looking soft robots capable of grasping, walking, or swimming. However, the growth in publication numbers does not always reflect the real progress in the field since many manuscripts employ very similar ideas and just tweak soft body geometries. Therefore, we unreservedly agree with the sentiment that future research must move beyond "soft for soft's sake." Soft robotics is an undoubtedly fascinating field, but it requires a critical assessment of the limitations and challenges, enabling us to spotlight the areas and directions where soft robots will have the best leverage over their traditional counterparts. In this perspective paper, we discuss the current state of robotic research related to such important aspects as energy autonomy, electronic-free logic, and sustainability. The goal is to critically look at perspectives of soft robotics from two opposite points of view provided by early career researchers and highlight the most promising future direction, that is, in our opinion, the employment of soft robotic technologies for soft bio-inspired artificial organs.
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Affiliation(s)
- Falk J Tauber
- Cluster of Excellence livMatS, FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg im Breisgau, Germany.,Plant Biomechanics Group (PBG) Freiburg, Botanic Garden of the University of Freiburg, Freiburg im Breisgau, Germany
| | - Viacheslav Slesarenko
- Cluster of Excellence livMatS, FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg im Breisgau, Germany
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5
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Liu B, He L, Li M, Yu N, Chen W, Wang S, Sun L, Ni M, Bai L, Pan W, Sun P, Lin J, Huang W. Improving the Intrinsic Stretchability of Fully Conjugated Polymer for Deep-Blue Polymer Light-Emitting Diodes with a Narrow Band Emission: Benefits of Self-Toughness Effect. J Phys Chem Lett 2022; 13:7286-7295. [PMID: 35916779 DOI: 10.1021/acs.jpclett.2c02071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
It is challenging to construct the intrinsically stretchable active layer of rigid conjugated polymers (CPs) toward flexible deep-blue light-emitting diodes (FLEDs). Inspired by the self-toughness effect, sacrificial hydrogen bonding (H-bonding) and a cross-linked network synergistically enabled polydiarylfluorene (PFs-NH) films to present efficient deep-blue emission and excellent intrinsic stretchability. In particular, a cross-linked network structure presenting viscoelasticity behaviors, which was successfully inherited into postprocessed films with interchain interpenetration and a crystallinity domain and behaved as energy absorption and dissipation centers, was induced by the interchain H-bonding interaction in toluene (Tol) precursor solutions where the storage moduli (G') gradually exceeded the loss moduli (G″). Subsequently, intrinsic stretchable films with a tensile rate of 30% were prepared from Tol solutions, different from the brittle films from polar solvents. Eventually, narrow band, deep-blue PLEDs showed a maximum EQE of 1.28% and a full width half-maximum (fwhm) of 28 nm. Therefore, the self-toughness effect induced by hierarchical structures will be feasible to obtain high-performance FLEDs.
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Affiliation(s)
- Bin Liu
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Liangliang He
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Mengyuan Li
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Ningning Yu
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Wenyu Chen
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Shengjie Wang
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Lili Sun
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Mingjian Ni
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Lubing Bai
- Frontiers Science Center for Flexible Electronics & Institute of Flexible Electronics (IFE), Northwestern Polytechnical University (NPU), Xi'an 710072, China
| | - Weichun Pan
- School of Food Science and Biotechnology, Zhejiang Gongshang University, 18 Xuezheng Road, Hangzhou 310018, China
| | - Pengfei Sun
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China
| | - Jinyi Lin
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
| | - Wei Huang
- Key Laboratory of Flexible Electronics (KLoFE) and Institute of Advanced Materials (IAM), Nanjing Tech University (Nanjing Tech), 30 South Puzhu Road, Nanjing 211816, China
- Frontiers Science Center for Flexible Electronics & Institute of Flexible Electronics (IFE), Northwestern Polytechnical University (NPU), Xi'an 710072, China
- State Key Laboratory of Organic Electronics and Information Displays & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing 210023, China
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6
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Huang K, Yuan Y, Baojun X. A Critical Review on the Microencapsulation of Bioactive Compounds and Their Application. FOOD REVIEWS INTERNATIONAL 2021. [DOI: 10.1080/87559129.2021.1963978] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Kehao Huang
- Food Science and Technology Program, BNU-HKBU United International College, Zhuhai, China
- Department Of Food Science And Agricultural Chemistry, McGill University, Quebec, Canada
| | - Yingzhi Yuan
- Food Science and Technology Program, BNU-HKBU United International College, Zhuhai, China
- Department Of Biochemistry, University College London, London, UK
| | - Xu Baojun
- Food Science and Technology Program, BNU-HKBU United International College, Zhuhai, China
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7
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Unexpected organic hydrate luminogens in the solid state. Nat Commun 2021; 12:2339. [PMID: 33879783 PMCID: PMC8058042 DOI: 10.1038/s41467-021-22685-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 03/23/2021] [Indexed: 01/01/2023] Open
Abstract
Developing organic photoluminescent materials with high emission efficiencies in the solid state under a water atmosphere is important for practical applications. Herein, we report the formation of both intra- and intermolecular hydrogen bonds in three tautomerizable Schiff-base molecules which comprise active hydrogen atoms that act as proton donors and acceptors, simultaneously hindering emission properties. The intercalation of water molecules into their crystal lattices leads to structural rearrangement and organic hydrate luminogen formation in the crystalline phase, triggering significantly enhanced fluorescence emission. By suppressing hydrogen atom shuttling between two nitrogen atoms in the benzimidazole ring, water molecules act as hydrogen bond donors to alter the electronic transition of the molecular keto form from nπ* to lower-energy ππ* in the excited state, leading to enhancing emission from the keto form. Furthermore, the keto-state emission can be enhanced using deuterium oxide (D2O) owing to isotope effects, providing a new opportunity for detecting and quantifying D2O. Developing organic photoluminescent materials with high emission efficiencies in the solid state under a water atmosphere is important for practical applications. Here, the authors report the formation of intra- and intermolecular hydrogen bonds in a tautomerizable Schiff base and intercalation of water in the crystal lattice leading to a luminescent organic hydrate.
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8
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Liu D, Shen Y, Jiang P, Thin Wai P, Zhang Z, Zhang P, Agus H, Nie Z, Zhao M, Zhao H. An efficient cold-resistant strategy: Synthesis and application of green cold-resistant bio-based plasticizer for poly(vinyl chloride). Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2020.110154] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Wang Y, Cheng Q, Liu J, Tariq Z, Zheng Z, Li G, Kaplan DL, Wang X. Tuning Microcapsule Shell Thickness and Structure with Silk Fibroin and Nanoparticles for Sustained Release. ACS Biomater Sci Eng 2020; 6:4583-4594. [PMID: 33455196 DOI: 10.1021/acsbiomaterials.0c00835] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Microcapsules have attracted widespread interest for their unique properties in encapsulation, protection, and separation of active ingredients from the surrounding environment. However, microcapsule carriers with controllable shell thickness, permeability, good mechanical properties, and thermostability are challenging to obtain. Herein, robust and versatile composite microcapsules were fabricated using SiO2 nanoparticle-stabilized (Pickering) oil emulsions as core templates, while silk fibroin (SF) was assembled at the oil/water interface. This process resulted in the formation of physically and chemically stable microcapsules with a thick (∼800 nm) shell that protected the encapsulated ingredient from high shear forces and high temperatures during spray-drying. SiO2 nanoparticles were randomly distributed in the shell matrix after preparation, making the microcapsules mechanically robust (4.48 times higher than control samples prepared using surfactant Tween 80 instead of the SiO2 nanoparticles), as well as thermostable (retained shape to 900 °C). The microcapsules displayed tunable drug release by adjusting the SF content in the shell. Under optimal conditions (weight ratio of SiO2/SF = 7:10, corn oil content about 55 wt %), a model drug (curcumin) was encapsulated in the SF microcapsules with an encapsulation efficiency up to 95%. The in vitro drug release from these SF microcapsules lasted longer than control microcapsules, demonstrating the capability of these novel microcapsules in sustaining drug release.
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Affiliation(s)
- Yongfeng Wang
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
| | - Qingqing Cheng
- Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, P. R. China
| | - Jian Liu
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
| | - Zeeshan Tariq
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
| | - Zhaozhu Zheng
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
| | - Gang Li
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Xiaoqin Wang
- National Engineering Laboratory for Modern Silk, Soochow University, 199 Renai Road, Suzhou Industrial Park, Suzhou, Jiangsu 215123, P. R. China
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10
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Calvino C, Henriet E, Muff LF, Schrettl S, Weder C. Mechanochromic Polymers Based on Microencapsulated Solvatochromic Dyes. Macromol Rapid Commun 2020; 41:e1900654. [PMID: 32134544 DOI: 10.1002/marc.201900654] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/07/2020] [Indexed: 12/19/2022]
Abstract
The development of polymers with built-in sensors that provide readily perceptible optical warning signs of mechanical events has received considerable interest. A simple and versatile concept to bestow polymers with mechanochromic behavior is the incorporation of dye-filled microcapsules. Such capsules release their cargo when their shell is damaged, and the dye is subsequently activated through a chemical or physical change that causes a chromogenic response. Here, we report the preparation of fluorescent poly(urea-formaldehyde) microcapsules containing solutions of a solvatochromic cyanostilbene dye and their integration in different polymers. When objects made from such composites are damaged, the dye solution is released from the containers, diffuses into the matrix, and the solvent evaporates. As a result, the polarity around the dye molecules changes, and this leads to a change of the fluorescence color. Alternatively, the dye is blended into the polymer matrix, microcapsules are loaded with a solvent, and the release of the latter triggers the color change. Both mechanisms afford ratiometric signals because the capsules that remain intact or dye molecules that are not exposed to the solvent can be used as a built-in reference; therefore, a quantitative assessment of the damage inflicted on the material is a priori possible.
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Affiliation(s)
- Céline Calvino
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg, CH-1700, Switzerland.,Pritzker School of Molecular Engineering, University of Chicago, 5640 S. Ellis Ave., Chicago, IL, 60637, USA
| | - Emma Henriet
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg, CH-1700, Switzerland.,Université de Technologie Belfort-Montbéliard, Rue de Leupe, Sevenans, 90400, France
| | - Livius F Muff
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg, CH-1700, Switzerland
| | - Stephen Schrettl
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg, CH-1700, Switzerland
| | - Christoph Weder
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg, CH-1700, Switzerland
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11
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Time-dependent solid-state molecular motion and colour tuning of host-guest systems by organic solvents. Nat Commun 2020; 11:77. [PMID: 31911631 PMCID: PMC6946670 DOI: 10.1038/s41467-019-13844-5] [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] [Received: 09/10/2019] [Accepted: 11/27/2019] [Indexed: 12/31/2022] Open
Abstract
Host-guest complex solid state molecular motion is a critical but underexplored phenomenon. In principle, it can be used to control molecular machines that function in the solid state. Here we describe a solid state system that operates on the basis of complexation between an all-hydrocarbon macrocycle, D4d-CDMB-8, and perylene. Molecular motion in this solid state machine is induced by exposure to organic solvents or grinding and gives rise to different co-crystalline, mixed crystalline, or amorphous forms. Distinct time-dependent emissive responses are seen for different organic solvents as their respective vapours or when the solid forms are subject to grinding. This temporal feature allows the present D4d-CDMB-8⊃perylene-based system to be used as a time-dependent, colour-based 4th dimension response element in pattern-based information codes. This work highlights how dynamic control over solid-state host-guest molecular motion may be used to induce a tuneable temporal response and provide materials with information storage capability. Host-guest solid state molecular motion is a critical but underexplored phenomenon which can be used to control molecular machines that function in the solid state. Here, the authors describe a solid state machine that shows solvent vapour- and mechanically-induced molecular motion that allows access to different crystalline and amorphous forms.
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