CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Kun Qian,Yan Shao,Zairan Yang,Shimei Jiang
Photoresponsive polymer materials, in particular, light-driven liquid crystal polymer networks (LCNs) have attracted much attention due to their rapid and significant capacity for photodeformation. However, a single shape change could not meet the growing needs of the information encryption field. Therefore, we aimed to find a photoluminescent and photochromic LCN to enrich the application of photodeformable materials. Here, a light-driven LCN consisting of two distinct kinds of photosensitive moieties, cyanostilbene (CS) and spiropyran (SP), named CS∙SP∙LCN, has been designed and synthesized. The resultant LCN film displayed multiple photo/thermal responsive properties. On the one hand, the trans – cis photoisomerization of CS gave the film capacity for photodeformation. On the other hand, the reversible conversion between ring-closed SP and ring-opened merocyanine (MC) under alternating stimulation of UV irradiation and heating gave the film capacity for tunable photoluminescence and photochromism. The CS∙SP∙LCN film can bend and change color/luminescence under UV irradiation, leading to multi-element writing simultaneously. Then, the written information could be hidden by heating and stretching. Notably, the film resumed bending after the second heating due to the good stability of the cis isomer of CS, realizing the first decryption. Finally, the color/luminescence of the film resumed after the second UV irradiation, completing the second decryption of the information. The CS∙SP∙LCN films synthesized in this study could realize multi-element encryption and step-by-step decryption through the cooperation of CS and SP, achieving more advanced information storage and encryption possibilities.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2020
·
IF 4.613
Guangliang Hou,Shenxi Min,Yuhan Zhao,Bin Dong,Lina Zhang,Dahua Li,Weichun Wu,Huifang Zhu,Bo Song
In this study, we synthesized an amphiphilic α-cyanostilbene derivative ( E -form)-1-(12-(2-(2-(benzo[d]thiazol-2-yl)-2-cyanovinyl)-5-(diethylamino)phenoxy)dodecyl)pyridin-1-ium bromide (denoted by BCPB). As being dissolved in aqueous solution, BCPB shows strong emission of excimers at around 660 nm due to the formation of aggregates. Addition of different amount of CB[7] into the solution leads to the emission shift from 660 nm, firstly to 540 nm and then to 588 nm. The emission shift is attributed to the two-step assembly driven by the concentration of CB[7], and the molar ratios of CB[7]/BCPB (denoted by R m ) play a critical role for the shift. As R m ≤ 4, CB[7] mainly interacts with the cationic pyridinium group of BCPB to form BCPB@CB[7] complex. As R m > 4, another CB[7] binds to the diethylamino group at one end of α-cyanostilbene to form BCPB@CB[7] 2 complex. The two-step assembly well explains the emission shift of BCPB.
研究领域:
超分子化学
·
材料科学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
Soft Matter
·
2021
·Vol. 17
·期 40
·9040-9046
·
IF 3.679
Tianwen Fan,Bangyi Zhou,Hongyu Guo,Fafu Yang
In previous studies, the increasing alkyl length of liquid crystalline molecules enhanced the chiral transfer and resulted in better CPL performance. But no work concerned the influence of alkyl lengths on CPL properties for non-liquid crystalline systems. In this research, three R-binaphthol-based cyanostilbene derivatives with various alkyl chains (BC-5, BC-8 and BC-12) were prepared in yields of 60–69%. They did not exhibit liquid crystalline behavior but were seen as soft materials at room temperature. They displayed excellent AIE fluorescence in aggregated states. Chiroptical investigations suggested good CD and CPL properties for their cyanostilbene units, indicating the successful chiral transfer from the binaphthol moieties to cyanostilbene units. Moreover, the values of gabs for CD signals and glum for CPL signals displayed the changing order of BC-5 > BC-8 > BC-12. These results suggested that the shorter alkyl chains for non-liquid crystalline systems led to stronger CPL emission, which was opposite to the results of the liquid crystalline molecules. This work provided a new strategy for the design and synthesis of chiroptical materials with good CPL properties based on non-liquid crystalline molecules.
研究领域:
有机化学
·
材料科学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 23
·5811
·
IF 4.2
Bian Li,Junde Zhang,Juan Wang,Xiaofang Chen
Cyanostilbene (CS)-related conjugated groups can be considered as dual functional groups of AIEgen and mesogen to construct photoluminescent liquid crystals, and it is essential to study the relationship between their molecular structures and compound properties systematically. In this paper, we designed and synthesized linear and bent-shaped CS derivatives containing ester- and amide-connecting groups and different substituted numbers of alkoxy tails. Their phase behaviors and photophysical properties were investigated in depth. The bent-shaped compounds with the mono-substituted alkoxy tail exhibit a smectic C structure, and those containing two or three alkoxy tails possess a hexagonal columnar phase structure. The compounds exhibit aggregation-induced emission (AIE) properties in tetrahydrofuran (THF)/water mixtures. When the water fraction increases to a certain threshold, a dramatic increase in emission intensity and a red-shift in the fluorescence emission peak are detected. The emission peaks of the ester-type compounds in solid states are around 480 nm, and those of the amide-type compounds are extended to 590 nm, exhibiting versatile luminescent colors. Moreover, thermochromic and photochromic fluorescence-responsive properties are witnessed in these CS derivatives. This work provides a new strategy for the design and synthesis of fluorescent liquid crystalline materials with multiple response properties.
研究领域:
材料化学
·
光化学
·
分子设计
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2018
·
IF 3.741
Yongjie Yuan,Jindi Li,Lifang He,Hailiang Zhang
In this paper, a series of side chain liquid crystal polymers (SCLCPs) containing cyanostilbene cores, alkoxy tail namely poly[(Z)-6-(4-(1-cyano-2-(4-(alkoxy)phenyl)vinyl)phenoxy)hexyl methacrylate]s (abbreviated as PM6PVPCm, m is the alkoxy tail length) were synthesized and the effects of the alkoxy tail length on the properties of the SCLCPs were explored. The structures and properties of the SCLCPs were measured by 1 H nuclear magnetic resonance ( 1 HNMR), thermogravimetric analysis (TGA), polarized optical microscopy (POM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), ultraviolet spectroscopy (UV) and photoluminescence (PL) measurements. Experimental results showed that all polymers enjoyed excellent thermo-stability, with 5% weight percentage loss temperatures up to 340 °C. All polymers also exhibited stable smectic liquid crystallinity and the alkoxy tail length also had a great impact on the mesophase behavior. The clearing point (Ti) showed an increasing trend with increase of the alkoxy tail length. All polymers showed weak emission in dilute solutions while emitted stronger fluorescence when aggregated in non-solvent or in the solid state, displaying an interesting characteristic of aggregation-induced emission enhancement (AIEE). The luminescent properties of polymers are sensitive to alkoxy tail length and their solid-state fluorescence quantum yield increased with the increasing alkoxy tail length. The solid-state fluorescence quantum yield of PM6PVPC18 is >8.9-fold higher than PM6PVPC1.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2019
·Vol. 10
·期 21
·2706-2715
·
IF 4.76
Yongjie Yuan,Lifang He,Jindi Li,Hailiang Zhang
A series of luminescent side chain polymers containing a D–π-A structure and different flexible spacer lengths, namely, poly[(Z)-ω-(4-(1-cyano-2-(4-cyanophenyl)vinyl)phenoxy)alkyl methacrylate]s (PMmPVPCN, m = 2, 4, 6, 8), were successfully prepared. With the combination of aggregation-induced emission enhancement (AIEE) luminogens and mesogens, the resultant polymers are expected to possess both liquid crystal characteristics and AIEE characteristics. The phase structure of PMmPVPCN was explored by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and one-dimensional wide-angle X-ray diffraction (1D WAXD). Photophysical properties of PMmPVPCN were studied by UV spectra and fluorescence spectra. Test results suggested that the phase structure of PMmPVPCN transformed from the amorphous phase (PMmPVPCN, m = 2, 4) to the nematic phase (PMmPVPCN, m = 6, 8) with the increase of polymer spacer length. All the synthetic monomers and polymers exhibited AIEE properties and the luminescence behavior of PMmPVPCN was associated with their chemical structure. The solid fluorescence quantum yields of PMmPVPCN increased from 22.4% to 42.7% with increasing spacer length. The polymer films also showed reversible fluorescence photo-responsive properties. The emission color and the emission intensity of polymer films changed when exposed to a 365 nm UV lamp. The change process was reversible and they could turn back to their original state when irradiated with a 254 nm UV lamp or heated at higher temperature.
研究领域:
材料科学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）