ChemistrySelect
·
2022
·Vol. 7
·期 44
·e202203402
·
IF 2.307
Xiaoying Ma,Lei Shi,Yao Fu,Buyue Zhang,Xiufeng Zhang
Graphical The cyclic induction of H-aggregates and J-aggregates can be achieved by adding rare earth ions, methanol and EDTA to the MTC solution. The intuitive color expression can be used as a La 3+ detection switch. In recent years, the assembly of cyanine dye supramolecular aggregates has been a very important task because its photophysical and photochemical properties are widely used in many scientific fields, such as, materials, biomedical and industrial. In this work, H- and J-aggregates of cyanine dyes were constructed under controllable conditions, and a simple method was developed to achieve cycle induction around these aggregates which induced by rare earth ions, and the process can be repeated for many cycles. Assembly and circulation induce these aggregates to be easy to manipulate and identify, which can be directly observed with the naked eye. This simple supramolecular assembly provides another direction in the field of sensors, while bringing a new idea to the control of supramolecular aggregates.
研究领域:
材料科学
·
生物医学
·
工业化学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2015
·Vol. 39
·期 7
·5750-5758
·
IF 3.086
Yinghui Bian,Jinshe Chen,Shaotang Xu,Yulu Zhou,Lijun Zhu,Yuzhi Xiang,Daohong Xia
Two novel metal-free phthalocyanines have been designed and synthesized, namely tetra{[1H-benzo(d)imidazol-2-yl]thiol}phthalocyanine (TBIT-Pc) and tetra{[benzo(d)thiazol-2-yl]thiol}phthalocyanine (TBTT-Pc). These two compounds showed similar structures, while imidazolyl-NH in the substitutes of TBIT-Pc could form more hydrogen bonds. TBIT-Pc and TBTT-Pc were fully characterized by elemental analysis, 1H NMR, MALDI-TOF MS, FT-IR and the UV-Vis absorption spectrum. The self-assembly properties of TBIT-Pc and TBTT-Pc were comparatively studied. TBIT-Pc and TBTT-Pc were present as monomers in DMF in the concentration range of 9.04–20.3 μM. Depending mainly on the intermolecular hydrogen bonding (N–H⋯N) between benzimidazole substitutes, “head-to-tail” J-aggregates of TBIT-Pc were formed in DMSO, while there was no aggregation of TBTT-Pc in the same solvent. “Face-to-face” H-aggregates of TBIT-Pc and TBTT-Pc were formed with the addition of water to the solutions of DMSO, and the degree of aggregation increased with the introduction of H-bonds (N–H⋯N) in the benzimidazole substitutes of TBIT-Pc. The atomic force microscope (AFM) image and dynamic light scattering (DLS) displayed the formation of well-defined nanoparticles with a diameter of ca. 30 ± 15 nm with J-type aggregation of TBIT-Pc. And the dendritic nanostructures with H-aggregates of TBIT-Pc and TBTT-Pc with different size were observed from transmission electron microscopy (TEM) images. The possible mechanism of the effect of H-bonds on the formation of J-aggregates of TBIT-Pc and the H-aggregation of TBIT-Pc and TBTT-Pc was also discussed. In the formation process of aggregates, H-bonds and π–π interaction may be the dominant factors. In addition, the nanostructures fabricated from TBIT-Pc and TBTT-Pc showed good semiconducting properties revealed by current–voltage measurements.
研究领域:
超分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2017
·
IF 2.714
Jingwen Song,Kai Ma,Tifeng Jiao,Ruirui Xing,Lexin Zhang,Jingxin Zhou,Qiuming Peng
Graphene oxide (GO)-based nanocomposite films via facile and appropriate self-assembly methods have demonstrated many potential applications in wide fields. This study demonstrates a facile and clean route to prepare graphene oxide-dye composite films using Langmuir-Blodgett (LB) technique at room temperature. By electrostatic interaction between cationic dye molecules and negatively charged GO sheets as well as π-π interactions, GO-dye composite LB films were formed spontaneously. As a soft platform for dye molecules, GO sheets induce dye molecules to self-assemble and form highly ordered structures containing H-aggregates and/or J-aggregates. The morphological characterization results show the formation of GO-dye composite films with smooth and dense surfaces. And the spectral results reveal that dye molecules stack in well-organized aggregates on the surface of GO sheets corresponding to monomers in bulk solution. The present research work about GO-dye composite films by LB method may provide new clues to prepare organized composite films and demonstrate potential applications in many fields.
研究领域:
材料科学
·
纳米科技
·
表面化学
·
胶体与界面科学
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功能薄膜
✓ 已验证
DOI
高影响因子
Soft Matter
·
2018
·Vol. 14
·期 32
·6667-6677
·
IF 3.709
Yonggang Shangguan,Mingguo Liu,Lei Jin,Mengjie Wang,Zhengke Wang,Qiang Wu,Qiang Zheng
A novel thermo-thickening behavior of a chitosan-g-polyacrylamide (CS-g-PAM, GPAM) aqueous solution is reported for the first time in this work. The viscosity of GPAM aqueous solutions significantly increases above a critical temperature upon heating, as observed in dynamic and steady rheological experiments. Differing from the widely reported hydrophobic modified CS, GPAM was prepared by grafting hydrophilic polyacrylamide side chains onto the CS backbone, therefore the thermo-thickening behavior of the GPAM aqueous solution could not be explained by the usual thermo-thickening mechanism induced by the additional hydrophobic moiety or LCST segment. The origin of the thermo-thickening in GPAM solutions was explored using transmission electron microscopy (TEM), dynamic light scattering (DLS), and nuclear magnetic resonance (NMR) tests of the GPAM solution. A transformation from a hydrogen bonding (H-bonding) aggregate to a hydrophobic aggregate upon heating was confirmed to be responsible for the thermo-thickening. The heating initiates a transformation of large loose H-bonding aggregates into abundant small compact ones formed by self-assembled hydrophobic chitosan backbones, resulting in aggregate associations and thus flocculated aggregate networks. Some factors of the thermo-thickening were investigated and discussed in detail, including the heating history, concentration, grafting ratio, and length of the PAM side chain. Besides the influence caused by the heating history, this thermo-thickening process is influenced by kinetic factors, including the mobility of the macromolecule chains and the formation of new aggregate networks that are dependent on the number of hydrophobic clusters.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Chenxiao Yan,Qingqing Zhang,Heng Gao,Xiong Zheng,Tong Yang,Guoxiang Zheng,Xiaoshun Zhou,Yong Shao
DNA templated dye assemblies pave an easy way to regulate the optical properties of molecular aggregates. G-quadruplexes (G4s) provide versatile DNA platforms for the dye assemblies since their foldings can be easily tuned by cation ions and sequences. In this work, we found that the G4 handedness can be used to control the aggregate chirality of a dye of 3,3′-diethylthiacarbocyanine (DiSC 2 (3)). The left-handed and right-handed G4s can template the concurrent formation of the J- and H-aggregates of DiSC 2 (3) with emergence of the featured absorption spectra. However, the chiral J-aggregate of DiSC 2 (3) can be formed only on the left-handed G4s, while the chiral H-aggregate is otherwise grown only on the right-handed G4s, as confirmed by the induced circular dichroism (ICD) spectra with the characteristic splitting bands. Additionally, these G4s even at tens of nM level are efficient to produce these chiral aggregates, demonstrating the high sensitivity of G4s in creating these optically active dye assemblies. The possible growth sites of the aggregates are proposed by the sequence length-dependent assemblies. Our work will provide a new way to control the chiral assemblies of dye aggregates via the G4 handedness.
研究领域:
化学
·
材料科学
·
生物物理
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2019
·
IF 5.997
Yuming Chen,Peng Liang,Zhen Yue,Wei Li,Chuanding Dong,Binbo Jiang,Jingdai Wang,Yongrong Yang
Chain entanglement was very important for adjusting the processability and mechanical property of nascent ultrahigh molecular weight polyethylene (UHMWPE). So far, it is still a mystery to unravel the formation mechanism of entanglements when the ethylene polymerization is conducted by the heterogeneous catalysts. In this study, a series of weakly entangled UHMWPE was synthesized by the polyhedral oligomeric silsesquioxane/MgCl2 nanoaggregates modified Ziegler–Natta catalysts. The structure of nanoaggregates was evaluated by X-ray photoelectron spectroscopy, density functional theory simulations, and scanning probe microscope experiments, where the coordination strategy of MgCl2 and hydroxyl of POSS was investigated. These nanoaggregates presented extremely low activity on ethylene polymerization and were proved to serve as isolators for separating the active sites and growing chains. The entanglement density of nascent UHMWPE (reflected by the value of initial storage modulus G′(t=0)) was exponentially decayed with the polymerization activity of increased numbers of nanoaggregates. Importantly, this exponentially decayed effect contributed by increased numbers of POSS/MgCl2 isolators offset the rapid power function increment of entanglements upon rising the temperature, which was the essential reason for the successful synthesis of weakly entangled UHMWPE even at 85 °C. Finally, we have proposed the dependence and sensitivity of G′(t=0) (i.e., indicating the initial entanglement density of nascent polymers) on the polymerization activity, which was able to trace the formation of entanglements during polymerization through the POSS modified heterogeneous catalyst.
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
Nanomaterials
·
2019
·Vol. 9
·期 3
·363
·
IF 4.034
Xinzhi Wang,Jianguo Tang,Guanghui Wang,Wei Wang,Junjie Ren,Wei Ding,Xinbo Zhang,Yao Wang,Wenfei Shen,Linjun Huang,Laurence A. Belfiore
In this research contribution, nano-aggregates have been fabricated by introducing lanthanide (Ln3+) ions into solutions of amphiphilic diblock copolymers of polystyrene-b-poly (acrylic acid) (PS-b-PAA). The coordination of acrylic acid segments to lanthanide cations induces diblock copolymer (BCPs) self-assembly in order to design stable white luminescent hybrid nanoparticles with fine uniform particle size. The introduction of Ln3+ions (Eu3+and Tb3+) bestows the micelles, precisely white light, upon excitation of 342 nm. Lanthanide coordination cross-linking of poly (acrylic acid) segments, or blocks, endows the micelles higher thermal stability than that of BCPs micelles without cross-linking. As the most important key point of this work, the regular and stable nano-particles with high emission quality can make fully flexible electroluminescent devices with self-formation or uncoordinated into polymer hosts. Instead of inorganic luminescent nanoparticles with hard cores, this method can potentially apply for fully flexible white-light emitting diodes (FFWLEDs).Keywords:nano-aggregates;diblock copolymer;fully flexible;white-light
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER TESTING
·
2025
·
IF 6
Yulin Niu,Zhongjie Cheng,Yanliang Yue,Shichao Wang,Wenfei Shen,Yao Wang,Jun Li,Matt J. Kipper,Soo Wohn Lee,Laurence A. Belfiore,Jianguo Tang
In this study, an innovated Tb 3+ -induced polystyrene-co-acrylic acid aggregates (TIPAs) were synthesized to impart strong luminescent property and high mechanical enhancement on polyethylene terephthalate. The structure and photophysical properties of TIPAs were investigated, and their incorporation into poly(ethylene terephthalate) (PET) was explored to fabricate a novel hybrid luminescent PET-based hybrid material via melt blending. By adjusting the doping concentration of TIPAs (ranging from 0.3 wt% to 2 wt%), a comprehensive study was conducted on the crystallization behavior, mechanical properties, and fluorescence performance of the composite. The physicochemical properties of the materials were characterized using differential scanning calorimetry (DSC), X-ray diffraction (XRD), tensile testing, and fluorescence spectroscopy. The relative crystallinity of the composite TIPAs@PET increased by 38.2 %, and both the tensile strength and modulus improved by 41.4 % and 34.4 %, respectively, when the TIPA doping concentration was 1.2 wt%. Moreover, the fluorescence intensity of the hybrid luminescent PET material reached its maximum at a doping level of 1.2 wt%, while maintaining excellent transparency. The introduction of TIPAs not only endowed the PET polyester with enhanced fluorescence and mechanical properties but also acted as an efficient nucleating agent, promoting the crystallization of PET.
研究领域:
材料科学
·
高分子科学
·
纳米技术
·
光学材料
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Chao Wang,Shiheng Li,Yuyao Han,Zhenda Lu
A novel structure of a carbon-coated LiMnPO4 microcluster through emulsion-based self-assembly has been fabricated to yield a high-performance battery cathode. In this rational design, nanosized LiMnPO4 plates are assembled into microclusters to achieve a dense packing and robust interparticle contact. In addition, the conductive carbon framework wrapping around these clusters functions as a fast electron highway, ensuring the high utilization of the active materials. The designed structure demonstrates enhanced specific capacity and cycling stability in lithium-ion batteries, delivering a discharge capacity of 120 mAh g–1 after 200 cycles at 0.2 C. It also shows a superior rate capability with discharge capacities of 139.7 mAh g–1 at 0.05 C, 131.7 mAh g–1 at 0.1 C, and 99.2 mAh g–1 at 1 C at room temperature.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Soft Matter
·
2012
·Vol. 8
·期 14
·3856-3863
·
IF 4.39
Hua-Neng Xu,Shu-Feng Ma,Wei Chen
The effect of β-cyclodextrin (β-CD) on the aggregation behavior of a nonionic surfactant, Triton X-114 ((1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol), in aqueous solutions has been studied as a function of temperature by means of turbidity, dynamic light scattering (DLS), transmission electron microscopy (TEM), and rheo-small angle light scattering (rheo-SALS). The Triton X-114 (TX-114) solutions possess unique structural variations and display special aggregate transitions upon β-CD addition. In contrast to the reported aggregate disruption effect of β-CD for dilute nonionic surfactant solutions, aggregate growth is found in the aqueous TX-114 solutions of 93 mM upon β-CD addition. The micelle to vesicle transition induced by β-CD addition, which can greatly influence the turbidity and the viscosity of the solutions, is quantified by the characteristic length and aspect ratio of the aggregates. The characteristic length and aspect ratio of the aggregates change significantly after β-CD addition. It shows that aggregate growth may occur in nonionic surfactant–CD systems, as well as the reported ionic surfactant–CD systems. It is proposed that the CD–CD H-bonds create intermicelle interactions and promote aggregation of the CD/surfactant complexes, resulting in the formation of micrometer-scale phase-separated droplets.
研究领域:
化学
·
材料科学
·
生物物理学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2022
·
IF 5.999
Lijun Ding,Jie Yang,Kangrui Yin,Hao Cheng,Jing Li,Changhu Xue
Liposomes are regarded as the ideal nanocarrier for concurrent or separate delivery of nutraceuticals in the food industries. Precise control of the structural stability is essential for the processing, storage, and nutrition delivery of liposomes. Astaxanthin was found to significantly affect the membrane stability of liposomes by inserting into the phospholipid bilayers in a similar way to cholesterol. Compared with cholesterol, astaxanthin could significantly improve the phase transition temperature, membrane fluidity , and membrane compactness of liposomes. Additionally, the membrane stability was well modulated by controlling the distribution patterns of astaxanthin (monomers, H- and J-aggregates) in bilayers. For instance, astaxanthin H-aggregates could endow the liposomal membrane with highest rigidity and compactness. Additionally, astaxanthin aggregates, especially J-aggregates could greatly improve storage stability of liposomes, thus providing a novel strategy to regulate and optimize the stability of liposomes for their diversified applications.
研究领域:
纳米技术
·
食品科学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2017
·
IF 3.684
Zhukang Du,Feng Wang,Xueyi Chang,Jun Peng,Biye Ren
Percec-type substituted benzyl alcohol mini-dendrons as new hydrophobic end-cappers can effectively improve the thickening performance of hydrophobically modified ethoxylated urethanes (HEURs) in aqueous solution. To demonstrate the effects of substituted structure of Percec-type mini-dendritic end groups on aggregation and rheological properties of HEURs in aqueous solution and latex, three model HEURs end-functionalized by mono-, di- and tri-substituted benzyl alcohol mini-dendrons were synthesized, respectively. For a reasonable comparison, the total carbon number of substituted alkyl tails is set to be 24 for the three mini-dendritic end groups: HOCH 2 - Ph -C 24 H 49 ( C24 ), HOCH 2 - Ph -(C 12 H 25 ) 2 ( 2C12 ) and HOCH 2 - Ph -(C 8 H 17 ) 3 ( 3C8 ), which respectively correspond to single-, two- and three-tail according to their substituted degrees. Interestingly, rheological properties of these HEURs in aqueous solution and latex significantly depend on the substituted degree of mini-dendritic hydrophobes. The high-substituted mini-dendritic hydrophobes help HEURs to form a strong physical network with high thickening performance and fast relaxation in both aqueous solution and latex, because shorter alkyl tails in high-substituted dendritic hydrophobes will lead to a smaller aggregation number and a lower rheological activation energy . This work not only provides new insights into the connection of networks in solutions of mini-dendron functionalized HEURs but also offers a new approach to preparation of high performance thickeners used in water-borne systems.
研究领域:
材料科学
·
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）