CARBOHYDRATE POLYMERS
·
2025
·
IF 12.5
Jin Xu,Qirong Li,Jiugang Yuan,Xuerong Fan,Weidong Gao
Starch-based films suffer from brittleness and poor tensile properties, limiting their industrial applicability. In this study, magnetically modified starch (MMS) was prepared by covalently grafting azide-Fe 3 O 4 @SiO 2 nanoparticles onto the reducing ends of soluble starch via reductive amination and Cu(I)-catalyzed azide–alkyne cycloaddition (click chemistry). During film formation, application of a 1.4 T NdFeB magnetic field promoted chain alignment and crystallization. X-ray diffraction revealed a 19 % increase in crystallinity (from 9.6 % to 11.4 %), while FTIR analysis showed a 27 % enhancement in the (994 + 1047)/1022 ratio, indicating greater short-range molecular order. As a result, the tensile strength of MMS films increased to 19.8 ± 1.9 MPa, representing an 81.7 % improvement over native starch films (10.9 ± 1.4 MPa, p < 0.01). Meanwhile, the elongation at break decreased from 3.9 ± 0.8 % to 2.3 ± 0.3 %, reflecting enhanced molecular packing and reduced chain mobility. Superparamagnetic behavior ensured chain mobility only under field exposure, minimizing agglomeration after field removal. This work demonstrates a scalable, field-guided strategy to tailor starch film structure and performance, offering promising applications in eco-friendly packaging and biomedical materials.
研究领域:
材料科学
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食品科学
·
高分子化学
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产品关联
DOI
PubMed
高影响因子
Communications Materials
·
2024
·Vol. 5
·期 1
·1-9
·
IF 7.5
Li Maohua,Gong Ping,Zhang Zhenbang,Li Linhong,Chen Yapeng,Qin Yue,Guo Yingying,Yang Rongjie,Zhang Jianxiang,Zhou Yiwei,Xu Kang,Wang Yandong,Do Hainam,Jia Xiaofei,Cai Tao,Lin Cheng-Te,Jiang Nan,Yu Jinhong
High thermal conductive polymers have become more important because equipment requires high performance, high-energy density, and high integration. There are different strategies to make high thermal conductive polymers, among which is the synthesis of polymers in the liquid crystal phase. However, the thermal conductivity of such material is rarely beyond 1 W m −1 K −1 because of the disordered molecular directionality. The disordered directionality between crystal zones limits the thermal conductivity in a specific direction. Here, we show a method for unifying the direction of crystal zones by applying an external electric field on the liquid crystal monomers. Meanwhile, by exposing the transparent equipment and specially designed photopolymerisable monomer in UV light, the liquid crystal monomer is in situ polymerised into a liquid crystal polymer with a high intrinsic thermal conductivity of 1.02 W m −1 K −1 . The molecular alignment was characterised and resulted in the resultant high conductivity.
研究领域:
材料科学
·
热传导工程
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产品关联
DOI
高影响因子
Energies
·
2024
·Vol. 17
·期 16
·4022
·
IF 3
Yuheng Ni,Hongyue Tian,Ruifeng Gong,Hang Zhou,Wenjing Xu,Jian Wang,Xiaoling Ma,Fujun Zhang
In this work, layer-by-layer organic photovoltaics (LbL OPVs) were prepared by sequentially spin-coating PM1 and L8-BO solutions. The solvent additive 1,8-diiodooctane (DIO), which has a high boiling point, and solid additive l,3,5-trichlorobenzene (TCB), which has a high volatile, were deliberately selected to incorporate with the L8-BO solutions. The power conversion efficiency (PCE) of LbL OPVs was considerably enhanced from 17.43% to 18.50% by employing TCB as the additive, profiting by the concurrently increased short-circuit current density (JSC) of 26.74 mA cm−2and a fill factor (FF) of 76.88%. The increasedJSCs of LbL OPVs with TCB as additive were ascribed to the tilted-up absorption edge in the long wavelength range and the external quantum-efficiency spectral difference between LbL OPVs with and without TCB as an additive. The molecular arrangement of L8-BO and the PM1 domain was enhanced with TCB as an additive, which was most likely responsible for the increased charge mobilities in the layered films processed with additives. It was indicated that the dynamic film-forming process of the acceptor layers plays a vital role in achieving efficient LbL OPVs by employing additive strategy. Over 6% PCE improvement of the LbL OPVs with PM1/L8-BO as the active layers can be achieved by employing TCB as additive.
研究领域:
材料科学
·
光物理学
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产品关联
DOI
高影响因子
Nature Sustainability
·
2025
·
IF 27.1
Yu Kaiqing,Li Chao,Gu Wenhui,Wang Meilin,Li Jiatian,Wen Kai,Xiao Yicheng,Liu Shiyong,Liang Yan,Guo Wenjin,Zhao Weiqiang,Bai Jie,Ye Dongdong,Zhu Yutian,Zhu Meifang,Zhou Xiang,Liu Zunfeng
Developing high-performance bio-based fibres is highly desirable for improving the sustainability of materials. Cellulose is one of the most abundant bio-derived feedstocks to fabricate such materials. However, the fabrication of high-strength macro cellulose fibres is challenging due to the difficulty in obtaining ordered packing of cellulose molecular chains and nanocrystals in the macro-fibres. Here we develop a draw spinning/de-acetylation method to prepare cellulose fibres with highly ordered molecular packing that incorporates high strength in the obtained fibres. Specifically, a fibre draw spun from well-dispersed cellulose triacetate solution was de-acetylated to generate cellulose fibres, which were then twisted to spirally align the molecular chains. The resulting fibres exhibited mechanical strength of 3.08 GPa and toughness of 215.1 MJ m − 3 , much higher than existing fibre materials. This work paves the way to obtaining high-performance bio-based fibres.
研究领域:
材料科学
·
生物化学
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产品关联
DOI
高影响因子
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
·
2020
·Vol. 125
·期 13
·e2019JD032182
·
IF 3.821
Shumin Cheng,Lin Du,Christian George
Sea surface microlayers (SMLs) play an important role in the transport and fate of surfactants from both anthropogenic and biogenic sources. The formation of sea spray aerosols (SSAs) at the SML has been recognized as a critical pathway for the entry of surfactants into the atmosphere. Perfluorocarboxylic acids (PFCAs) have become increasingly concerning as a class of emerging organic pollutants, having high enrichment in surface seawaters due to their remarkable surface activity. Using artificial seawater coated by extensively existed surfactants, including stearyl alcohol (C18OH) and stearic acid (SA) as simplified models of the SML and fresh SSAs, the interfacial behaviors of soluble and insoluble PFCAs were examined. Information about lateral packing and chain conformation of films was obtained by means of Langmuir trough and infrared reflection-absorption spectroscopy (IRRAS). Perfluorooctanoic acid (PFOA) dissolved in aqueous subphases was found to be incorporated into lipid monolayers via alterations in surface pressure-area (π-A) isotherms. With negligible solubility, perfluorotetradecanoic acid (PFTA) formed condensed mixed monolayers with other lipids at the air-water interface. The mixed monolayers of C18OH/PFTA and SA/PFTA were expanded by the addition of sea salts into the pure water subphase. Compared with the π-A isotherms of SA/PFTA, decreased molecular areas were observed for those of C18OH/PFTA. This research suggests that PFCAs can be incorporated into air-water interfaces by acting as film-forming materials. The introduction of PFCAs will alter the surface properties and thus the atmospheric fate and behavior of SSAs and SMLs. Key Points Both soluble and insoluble perfluorocarboxylic acids can be incorporated into air-water interfaces by acting as film-forming materials Intermolecular interactions between fluorinated and nonfluorinated alkyl chains can affect interfacial molecular arrangements Alterations in surface packing warrant further discussion on implications for atmospheric processes from aqueous interfaces
研究领域:
环境科学
·
化学
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产品关联
DOI
高影响因子
ACS Nano
·
2015
·
IF 12.881
Qi Li,Yi Jia,Luru Dai,Yang Yang,Junbai Li
Diphenylalanine (FF) microrods were obtained by manipulating the fabrication conditions. Fourier transform infrared (FTIR), circular dichroism (CD), fluorescence (FL) spectroscopy, and X-ray diffraction (XRD) measurements revealed the molecular arrangement within the FF microrods, demonstrating similar secondary structure and molecular arrangement within FF microtubes and nanofibers. Accordingly, a possible mechanism was proposed, which may provide important guidance on the design and assembly manipulation of peptides and other biomolecules. Furthermore, characterization of a single FF microrod indicates that the FF microrod can act as an active optical waveguide material, allowing locally excited photoluminescence to propagate along the length of the microrod with coupling out at the microrod tips.
研究领域:
生物化学
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材料科学
·
光学
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产品关联
DOI
PubMed
高影响因子
Acta Pharmaceutica Sinica B
·
2018
·
IF 6.014
Shuzhen Ren,Mingyu Liu,Chao Hong,Guowen Li,Jiabin Sun,Jianying Wang,Lei Zhang,Yan Xie
Pharmaceutical cocrystals are a promising technology that can be used to improve the solubility of poor aqueous compounds. The objective of this study was to systematically investigate the solubility of myricetin (MYR) cocrystals, including their kinetic solubility, thermodynamic solubility, and intrinsic dissolution rate (IDR). The effects of pH, surfactant, ion concentration, and coformers on the cocrystal solubility were evaluated. Furthermore, single crystal structures of MYR, myricetin–isonicotinamide (MYR–INM) and myricetin–caffeine (MYR–CAF) cocrystals were analyzed to discuss the possible reasons for the enhancement of cocrystal solubility from the perspective of the spatial structure. The results indicated that the kinetic solubility of MYR cocrystals was modulated by pH and cocrystal coformer (CCF) ionization in buffer solution, while it primarily depended on the CCF solubility in pure water. In addition, the solubility of MYR cocrystals was increased in a concentration dependent fashion by the surfactant or ion concentration. The thermodynamic solubility of MYR–INM (1:3) cocrystals decreased with the increases of the pH value of the dissolution media. The IDR of MYR cocrystals was faster than that of MYR in the same medium and extremely fast in pH 4.5 buffer. The improved solubility of MYR cocrystals was probably related to the alternate arrangements of MYR and INM/CAF molecules and increased intermolecular distance. The present study provides some references to investigate the solubility behavior of pharmaceutical cocrystals.
研究领域:
药学
·
化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Jianai Chen,Mingjiao Sun,Yujie Dong,Weijun Li,Fener Chen
Mechanical stimulus-responsive materials are generally considered to be closely related to molecular packing in the solid state, underscoring the significance of regulating molecular packing via precise molecular design. In this study, flexible alkyl substituents were employed to adjust the molecular packing. By modifying alkyl substituents, predictable changes in the molecular packing of their derivatives were observed, resulting in adjustable ML properties. The DPA-PYZ-TB with a tert-butyl-side chain exhibited strong ML and MC stimulus response signals. The enhanced ML and MC performance can be attributed to the effective suppression of non-radiation through the helical crystal arrangement and strong intermolecular interactions. The relationship between molecular arrangement and ML/MC properties was validated through analysis of the single crystal structure and corresponding experimental results. This study offers valuable insights into the enigmatic ML process and the development of efficient luminous materials that utilize both MC and ML.
研究领域:
材料科学
·
晶体学
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产品关联
DOI
高影响因子
Journal of Engineered Fibers and Fabrics
·
2023
·
IF 2.9
Lei Zhao,Ting Zhu,Li Wei,Jumei Zhao,Qianwen Wang,Jun Wang
The PAN spinning solution was chosen as the spiral spinning research object. Laminar flow theory was used to straighten and align macromolecules, and spiral spinning needles were used to control the spiral twisting of straightened PAN macromolecules. The internal spiral arrangement of PAN nanofibers became more compact as the helix number of spinning needles increased. The TEM (transmission electron microscope) was used to photograph the motion trajectory of TiO2 (titanium dioxide) nanoparticles in nanofibers, which directly confirmed the feasibility of the spiral spinning principle. SEM (Scanning Electronic Microscopy) observations revealed that the appearance of the PAN nanofiber membranes changed to some extent under spiral physical technology. The analysis of the tensile and bursting properties of PAN nanofiber membranes demonstrated that the structure of the nanofibers changed significantly after spiral spinning. The pore structure, electrical resistance, and antibacterial properties of PAN nanofiber membrane all reached optimal values at the optimal helix number of spinning needle.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Peng Wang,Sultan Ahmed Khoso,Zhao Cao
The self-assembly of mixed surfactants at the air/water interface plays a crucial role in mineral flotation separation. This study aimed to investigate the molecular arrangement and synergistic adsorption of mixed surfactants at the air/water interface using molecular dynamics (MD) simulation and surface tension measurement. The stability of mixed surfactant solutions was also measured using dynamic light scattering and ζ potential. We investigated the mixture of octylhydroxamic acid (OHA) and dodecanol (DOD) surfactants at different weight ratios. The surface activity of the OHA/DOD mixture was characterized in detail, including the relative concentration distribution, structural properties, and radial distribution function. The MD simulations revealed that OHA/DOD was inserted into the water as a headgroup at the air/water interface, and the carbon chain extended into the air. A strong synergistic effect was observed between the two surfactants, and a dense monolayer film was formed at the air/water interface, demonstrating higher surface activity. With an increase in the DOD ratio, the hydrogen bond between the OHA headgroup and water molecules became stronger. The order of surface activity of the mixture was OHA:DOD = 1:1 > OHA:DOD = 2:1 > OHA:DOD = 4:1. In the temperature range from 24 to 30 °C, the surface tension decreased and the critical micelle concentration increased with increasing temperature. The addition of DOD changed the conformation of the mixed surfactants, which was beneficial to the aggregation of OHA/DOD complexes. When OHA:DOD = 1:1, the average particle size was the largest and the formed micelles were the most stable. The experimental results are consistent with the surface tension and simulation results.
研究领域:
化学工程
·
表面科学
·
计算化学
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Dongxu Shen,Yarong Liu,Chongchong Chen,Zhirong Yang,Hao Li,Shanghao Xiao,Wenjia Wu,Jingtao Wang
Precise construction of proton transfer pathways and modulation of proton carrier microenvironments are crucial for achieving high proton conduction in proton exchange membranes (PEMs). Despite extensive efforts to tailor these microenvironments, the underlying regulation of electron cloud density around proton carriers, intrinsically linked to proton conduction, remains largely overlooked. Herein, MIL-53-SO 3 H-X (X = –F, –Br, –H, –CH 3 ) nanosheets are synthesized via solvothermal coordination of Cr 3+ ions with functionalized terephthalic acid (BDC-X) ligands, followed by post-synthetic sulfonation at unsaturated Cr 3+ sites to anchor –SO 3 H groups. Density functional theory (DFT) calculations and experimental results reveal that electron-withdrawing –F groups enhance the electron cloud density around –SO 3 H sites, shortening transfer distance, aligning water molecules, and lowering the proton transfer barrier. Conversely, electron-donating –CH 3 groups deplete the electron cloud density in the –SO 3 H region, disrupting proton transport pathways. The MIL-53-SO 3 H-F nanosheet achieves an intrinsic proton conductivity of 298.3 mS cm −1 at 80 °C and 98% RH, a 4.5-fold increase over MIL-53-SO 3 H-CH 3 nanosheets (65.5 mS cm −1 ), as measured by the comb electrode. The corresponding lamellar membrane delivers a high peak power density of 734.8 mW cm −2 and remains stable for over 100 h in H 2 /O 2 PEM fuel cells (PEMFCs).
研究领域:
材料科学
·
电化学
·
能源材料
·
纳米材料
·
膜科学
·
燃料电池
✓ 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）