Helix-Induced Asymmetric Self-Assembly of π-Conjugated Block Copolymers: From Controlled Syntheses to Distinct Properties

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(21), P. 2954 - 2967

Published: Oct. 18, 2023

Conspectusπ-Conjugated polymers have gained significant interest because of their potential applications in optoelectronics, bioelectronics, and other domains. The controlled synthesis π-conjugated block optimizes performance enables novel properties functions. However, precise control the self-assembled architectures remains a formidable challenge. Inspired by helical biomacromolecules, supramolecular assemblies attention. Helical with an excess one-handed helicity can be optically active strong tendency toward self-assembly. Incorporating polymer into induce asymmetric assemblies, leading to chiral materials unique functionalities.To self-assembly architectures, are usually synthesized copolymers incorporating self-assembling characteristics. Although various been produced, is still challenging has rarely addressed. self-assembly, which transfers chirality polymer, resulting chiroptical functionalities. synthesizing hybrid containing two distinct blocks complicated. Some general strategies such as connecting chain ends preformed homopolymers extending prefabricated second monomer time-consuming require complex synthetic protocols. Therefore, developing for facile predictable molar mass, low dispersity, tunable composition practical importance.Recently, we investigated polyisocyanides, polyallenes, polycarbenes advanced Pd(II) Ni(II) catalysts. These were successfully incorporated polymers, including polythiophene, polyfluorene, poly(phenyleneethynylene), via one-pot sequential living polymerization monomers using Pd(II)- or Ni(II)-complexes As result, variety well-defined polymeric readily synthesized. copolymerized possess different structures mechanisms, copolymerization followed mechanism provided desired high yields narrow size distribution, composition.Remarkably, induces copolymer supramolecular, architecture optical properties. More interestingly, utilizing crystallization conjugated blocks, crystallization-driven helix-induced yielded family uniform single-handed dimensions, helicity. transfer rendered achiral emission white light over broad spectrum circularly polarized luminescence.

Language: Английский

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“Matching Rule” for Generation, Modulation and Amplification of Circularly Polarized Luminescence

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(8), P. 1188 - 1201

Published: April 5, 2024

ConspectusCircularly polarized luminescence (CPL) generated by chiral luminescent systems has sparked enormous attention in multidisciplinary field as it brings infinite potential for applications, such 3D optical displays, biological probes, and chiroptical sensors. Satisfying both the conditions of chirality (including fluorescence or phosphorescence) is a prerequisite constructing CPL materials. In this regard, whether organic, inorganic, hybrid systems, components generally involve effective coupling through covalent noncovalent bonds. For interactions, copolymerization monomers, although bonds provide high stability system, they inevitably tedious preparation procedures that connect together. bonds, take supramolecular assembly an example, elements achiral light-emitting units are transferred intermolecular their advantages include diversity building blocks, stimuli responsiveness brought well amplification signals coassembly. However, system may be poor, performance morphology difficult to predict. Gratifyingly, matching rule do not rely on together with interactions allows effortless construction, modulation, systems.In Account, we overview different strategies based rule, including fluorescence-selective absorption, circularly reflection, energy transfer (CPF-ET). Examples these illustrated focus helical polymers light appealing structures wide uses. instance, can convert racemic into one specific handedness simply overlapping polymer's circular dichroism (CD) spectra luminophore's emission spectra. employing selective reflection certain handedness's light, twisting power (HTP) polymer cholesteric liquid crystals (N*-LCs) gives glum. Additionally, CPF-ET, only spectrum donor absorption (or excitation) acceptor required overlap, no between two required. An outlook materials related which will avail optimization extension intriguing approach concludes Account. We hope Account offer insightful inspiration flourishing progress present exciting opportunities.

Language: Английский

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Enabling robust blue circularly polarized organic afterglow through self-confining isolated chiral chromophore

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 9, 2024

Abstract Creating circularly polarized organic afterglow system with elevated triplet energy levels, suppressed non-radiative transitions, and effective chirality, which are three critical prerequisites for achieving blue afterglow, has posed a formidable challenge. Herein, straightforward approach is unveiled to attain materials by covalently self-confining isolated chiral chromophore within polymer matrix. The formation of robust hydrogen bonds the matrix confers distinctly stabilized molecular state chromophores, endowing emission band at 414 nm, lifetime 3.0 s, luminescent dissymmetry factor ~ 10 −2 . Utilizing synergistic chirality transfer, full-color systems endowed doping colorful fluorescent molecules into designed polymers, empowering versatile applications. This work paves way streamlined design materials, expanding horizons various domains.

Language: Английский

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Helicity Control of Circularly Polarized Luminescence from Aromatic Conjugated Copolymers and Their Mixture Using Reversibly Photoinvertible Chiral Liquid Crystals

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(3), P. 3991 - 4002

Published: Jan. 6, 2024

We synthesized cyclic chiral compounds [(R)/(S)-D2s] by linking a photoresponsive bisbenzothienylethene (BTE) moiety with an axially binaphthyl moiety. Chiral nematic liquid crystals (N*-LCs) were prepared adding as dopants to host N-LCs. These N*-LCs exhibited reversible chirality inversion upon photoisomerization between the open and closed forms of BTE Here, mechanism underlying in was investigated comparing helical twisting powers (HTPs) (R)-D2s those analogous compounds. It found that containing is governed delicate balance two types opposite helicity, i.e., right-handed helicity inherently left-handed bearing intramolecularly induced chirality. Namely, moiety, which attributed intramolecular transfer from Thus, are double consisting intrinsically Photocontrol senses photoinversion achieved utilizing UV visible light irradiation steric effects substituents at rings (R)-D2s. In addition, photocontrol circularly polarized luminescence (CPL) using photoinvertible N*-LC. The achiral aromatic conjugated copolymers red, green, blue fluorescence dissolved mixed present N*-LC, they left- white CPL large dissymmetry factors (|glum|) ranging 0.2 1.0. CPLs reversibly photoswitched due PSS through irradiation.

Language: Английский

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Reversible Photochromism for Dynamically Tuning Full‐Color Circularly Polarized Luminescence Toward Multi‐Level Anti‐Counterfeiting Application

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(19)

Published: April 9, 2024

Abstract Photochromic circularly polarized luminescence (CPL) demonstrates broad application prospects in the field of advanced functional materials. However, current photochromic CPL focuses predominantly on single‐band adjustment, and how to achieve dynamically tunable multi‐band is still highly challenging. This work reports success utilizing reversible photochromism for realizing full‐color emission. flexible films are created consisting triple components: spiropyran (SP) working as matter, polyurethane (PU) matrix, chiral helical polyacetylene component. Further introducing blue fluorophore 9‐anthracene carboxylic acid (ACA) film, red emitted respectively through selective absorption/transmission fluorescence energy transfer (CPF‐ET). Doping film with diverse fluorophores provides Adding Zn 2+ further intensifies via forming merocyanine (MC)‐Zn complex. Taking advantage emission, anti‐counterfeiting, secondary encryption resulting materials demonstrated.

Language: Английский

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Size Control of Chiral Nanospheres Obtained via Nanoprecipitation of Helical Poly(phenylacetylene)s in the Absence of Surfactants

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(32)

Published: May 14, 2024

Abstract Nanostructuration of dynamic helical polymers such as poly(phenylacetylene)s (PPAs) depends on the secondary structure adopted by polymer and functional group used to connect chiral pendant PPA backbone. Thus, while PPAs with flexible scaffolds ( para ‐ meta ‐substituted, ω 1 <165°) generate nanoprecipitation low polydisperse nanospheres controllable size at different acetone/water mixtures, those a quasi‐static behavior presence an extended, almost planar ortho‐ substituted, >165°), aggregate into mixture spherical oval nanostructures whose is not controlled. Photostability studies show that poly(phenylacetylene) particles are more stable light irradiation than when dissolved macromolecularly. Moreover, photostability particle its screw sense excess. This fact, in combination encapsulation ability these particles, allows creation stimuli‐responsive nanocarriers, cargo can be delivered irradiation.

Language: Английский

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Molecular Order Imprint Polymerization of Furan–Thiophene-Based Monomers with Electrochemical Polymerization in Chiral Liquid Crystals

ACS Applied Polymer Materials, Journal Year: 2024, Volume and Issue: 6(5), P. 2504 - 2512

Published: Feb. 27, 2024

A polymerization reaction in chiral liquid crystal produced electro-optically active polymers from achiral furan–thiophene-based monomers. The set of prepared this study had characteristics molecular order and organic semiconductors. optically aromatic copolymers were synthesized via an electrochemical method cholesteric crystals (Ch-LCs). Electrical properties chirality can be tuned to choose suitable monomer units. obtained evaluated by polarizing optical microscopy (POM), circular dichroism, UV–vis spectroscopy, cyclic voltammetry, reflectance scanning electron microscopy, transmission atomic force microscopy. POM observations the products showed a vortex-type fingerprint texture. Polymerization monomers containing only two sites resultant compounds with good transcription texture Ch-LC electrolyte solution. membrane-forming behavior improved introducing furans at edges absorption bands derived polarons bipolarons as charge carriers conducting electrical redox process hydrazine vaporization treatment. control for activity was achieved.

Language: Английский

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Construction of Supramolecular Polymers and Covalent Polymers via the Same Monomers

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(32)

Published: April 8, 2024

Abstract Nature owns the ability to construct structurally different polymers from same monomers. While can be classified as covalent ( CPs ) and supramolecular SPs ), it is still difficult synthesize using monomers like nature do. Herein, M1 with two diazo salts on both ends was designed. Additionally, hydroquinone chosen M2 for existence of hydroxyl groups. When mixing at room temperature, self‐assembled via N…H hydrogen bonds. In another way, upon exposure ultraviolet irradiation when blending , were fabricated in presence The excellent thermal stability determined by TGA DSC, while great corrosion resistance detected acid or alkali immersion. this constructing kinds successfully achieved. This shows tremendous potential fields polymer science, chemistry, which would boom development polymers.

Language: Английский

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One‐Handed Helical Polyacetylenes Bearing Axially‐Chiral 2‐Arylpyridyl‐N‐Oxide Units for Efficient Chromatographic Enantioseparation of Chiral Aromatic and Aliphatic Alcohols

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(31)

Published: June 1, 2023

A series of poly(biarylylacetylene)s (PBAs) bearing axially-chiral (S)-and (R)-pyridyl-N-oxide residues with a methoxy, propoxy, or acetyloxy substituent at the 3-position biaryl units was synthesized. All PBAs formed preferred-handed helix, while helical sense preference varied depending on substituents despite same twist-sense units. Among them, propoxy-bound PBA showed an exceptionally high chiral recognition ability as stationary phase (CSP) for high-performance liquid chromatography (HPLC) and efficiently resolved not only various aromatic alcohols, but also variety aliphatic alcohols; latter still remains difficult to resolve by commercially-available CSPs in HPLC. Such practically-useful both handed PBA-based can be produced from racemic composed fully monomer through deracemization alcohol.

Language: Английский

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Fluorescence-Selective Absorption and Circularly Polarized Fluorescence Energy Transfer Assist the Generation of Multicolor Circularly Polarized Luminescence in Chiral Helical Polyacetylene-Based Janus Nanofibers

ACS Macro Letters, Journal Year: 2024, Volume and Issue: 13(6), P. 673 - 680

Published: May 16, 2024

Chiroptical nanomaterials with circularly polarized luminescence (CPL) performance have aroused increasing attention. Herein, multicolor CPL-active Janus nanofibers are prepared through a simple parallel electrospinning method using chiral helical polyacetylenes as the source and achiral fluorophores fluorescent source. Interestingly, despite direct spatial isolation between component component, blue green CPL emissions can still be obtained due to fluorescence-selective absorption behavior of polyacetylenes, satisfactory dissymmetric factor (glum) 2 × 10-2 2.5 10-3, respectively. Moreover, by taking advantage circular polarization fluorescence energy transfer process, red emission is further achieved donors fluorophore an acceptor. The present work offers facile approach prepare multilevel-structured chiroptical materials promising application potentials in flexible photoelectric device.

Language: Английский

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