CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2020
·
IF 2.627
Yexun Shi,Chang Li,Liming Shen,Ningzhong Bao
The graphene oxide powder (GOP) obtained from the spray drying process often exhibits poor re-dispersibility which is considered due to the partial reduction of GO sheets. The reduction of drying temperature can effectively increase the re-dispersibility of GOP, but result in a decreased drying efficiency. Herein, we found that the re-dispersibility of GOP is strongly affected by its microstructure, which is determined by the feed concentration. With the increase of feed concentration, the GO nanosheet assembly varies from the disordered stacking to relatively oriented assembly, making the morphology of the GOP transform from ball-like (the most crumpled one) to flake-like (the least crumpled one), and the 0.8 mg·ml −1 is the threshold concentration for the morphology, structure, and re-dispersibility change. Once the feed concentration reaches 0.8 mg·ml −1 , the appearance of the nematic phase in droplet ensures the relatively oriented assembly of GO sheets to form the layered structure with a low crumpling degree, which greatly improves the polar parts surface tension of the solid GOP, making the GOP easier to form hydrogen bonding with water during the redispersion process, thus stabilizing dispersion. This work provides useful information for understanding the relationships between the morphology, microstructure, and final re-dispersibility of GOPs.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
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2018
·
IF 3.046
Fang-Hao Niu,Zhi-De Hu,Hua Yan,Jian-Jian Yang,Han-Song Zhang
This work reports an investigation into the redispersibility of magnetorheological suspensions (MR suspensions) by testing the rheological properties of suspension sediment. By using a new freeze-sampling method, slices of sediment were taken from the bottom of the container with little changes on shear history which makes it possible to employ rheological measurement. Size distribution of particles contained in sediment was studied by a laser scattering method. Oscillatory and steady shear was employed to studying the rheological viscoelastic and flow behavior. Also, thixotropy and recovery behavior was also studied. The results obtained proved that redispersibility is a multifactor-dependent property which can be reflected from rheological responses of MR suspensions’ sediment. Hydrodynamic force and particle interaction which have significant influence on those properties were analyzed in this study. In addition, indexes correspond to different rheological properties were put forward to make a comparison quantitatively between traditional MR suspensions.
研究领域:
材料科学
·
流变学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
He Chen,Chunhong Qi,Luyan Shen,Qiang Fu,Zhiqiang Wang,Zhiyuan Xiong,Youyi Sun,Yaqing Liu
The reduced graphene oxide (rGO) nanosheets were modified by using polymeric nanospheres to adjust the d-spacings between dry rGO nanosheets. The experimental and computational studies show that the incorporation of polymeric nanospheres can effectively increase the d-spacing between dry rGO nanosheets, and meanwhile provide good compatibility of rGO with organic solvents. Specifically, when the d-spacing between nanosheets is greater than 14.0 nm, the dried rGO nanosheets can be well redispersed and stabilized in various organic solvents. This study thus provides a new technology that can produce dry rGO nanosheets with good re-dispersibility and stability in various organic solvents on a large-scale in a more environmental friendly manner.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Chen Cai,Guanghui Wang,Dongfei Xu,Cuiqiang Yan
This study aims to explore the redispersibility of dehydrated nanocellulose with p -toluenesulfonic acid ( p -TsOH) fractionated lignin as an eco-friendly and cost-effective capping agent, to cope with the challenge of irreversible agglomeration and thus loss of nanoscale of nanocellulose upon dehydration. The intermixing of nanocellulose and p -TsOH fractionated lignin was achieved using an aqueous ethanol solution as the medium and films of lignin-blending cellulose nanofibers (L + CNF) with excellent redispersing properties were obtained after facile air-drying. With 0.02 % ammonia as the dispersing solution, the dehydrated L + CNF film was able to achieve nearly 100 % redispersion yield after 30 min of mechanical agitation. If necessary, lignin in redispersed L + CNF can be removed by simple ethanol washing and centrifugation. In addition, redispersed L + CNF can be hybridized with poly(vinyl alcohol) (PVA) in a simple process to prepare PVA nanocomposite films with excellent hydrophobic, thermally stable, antibacterial, and mechanical properties. This study provided a sustainable and cost-effective solution to the dehydration/redispersion challenges of nanocellulose.
研究领域:
材料科学
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生物质工程
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产品关联
DOI
PubMed
高影响因子
Smart Materials and Structures
·
2018
·Vol. 27
·期 9
·095011
·
IF 2.963
Fang-Hao Niu,Zhi-De Hu,Hua Yan,Han-Song Zhang,Jian-Jian Yang
This work reports an investigation into the sedimentation stability and redispersibility of magnetorheological suspensions (MR suspensions). By applying a freeze sectioning method, slices of suspension layer were taken from a suspension column with minimum changes to shear history. The descent of the mudline was tracked, and the size distribution of particles contained in the suspension layer was studied using a laser scattering method. Oscillatory and steady shear was employed in studying the rheological flow behavior and viscoelasticity. Hydrodynamic force and particle interactions which have significant influence on those properties were analyzed in this study. In addition, indexes corresponding to sedimentation stability and redispersibility were put forward to make a quantitative comparison between three kinds of traditional MR suspension. The result shows that oleic acid could improve the sedimentation stability to a certain extent and hinder the formation of 'stiff cake', while nano-silica could significantly lower the sedimentation ratio but require considerable energy consumption to redisperse the suspension.
研究领域:
材料科学
·
胶体化学
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产品关联
DOI
高影响因子
REVIEW OF SCIENTIFIC INSTRUMENTS
·
2023
·Vol. 94
·期 1
·
IF 1.6
Lv Jingcheng,Wang Shiwei,Li Yao,Wu Mingyu,He Junxiang,Zhao Tong,Wei Yintao
Magnetorheological fluid (MRF) is a widely used smart material that suffers from sedimentation. Since sedimentation is unavoidable, it is crucial to study and improve the redispersibility of MRFs. However, previous redispersibility testing methods have problems, such as complicated operation and low precision. Simultaneously, a simple and effective method is urgently needed for high-precision modeling of MRF sedimentation to test the rheological properties of settled MRFs at different depths. After systematically analyzing the redispersion problem, this paper proposes decoupling the energy required for redispersing settled MRFs into two parts, which are related to different factors. These two parts are the energy required to separate the agglomerated particles (related to the MRF formula) and that to redisperse the settled MRF uniformly vertically against gravity (related to the solid concentration and packing limit). The energy that separates the agglomerated particles is proportional to the shear stress of slowly shearing the corresponding agglomerated samples, i.e., the yield stress. Thus, this paper proposes a simple microdamage quasi-static indentation method to measure the yield stresses of settled MRFs at different depths to characterize the redispersibility of the corresponding MRFs. Herein, this method is applied to study the mechanisms of the influences of surfactants, thixotropic agents, and their networks on the redispersibility of MRFs. The results indicate that a well-dispersed plate-like thixotropic agent network can effectively improve redispersibility, while surfactants with poor compatibility degrade redispersibility. In summary, this redispersibility test method will greatly facilitate studies of MRFs, such as optimizing the formulas and establishing sedimentation models.
研究领域:
材料科学
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流变学
·
机械工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Le Li,Han Tao,Bolang Wu,Ge Zhu,Ke Li,Ning Lin
Different from the conventional surface modification strategy, the end reaction based on the active aldehyde groups of cellulose nanocrystal (CNC) provides a targeted modification under the protection of its surface chemistry. With the purpose of promoting its redispersibility in water, the strategy of triazole end-grafting performed on CNC was proposed in this study, exhibiting the significant improvement on the redispersion and stability of nanocrystals in the aqueous suspension attributed to synergistic effect of steric stabilization and electrostatic repulsion. The end-modified CNC was then introduced into a natural rubber (NR) matrix to fabricate the composites with reactive compatibility from a thiol–ene click reaction. Ascribed to the formation of covalent linkage between nanofillers and matrix together with the architecture of the rigid percolating network, the mechanical properties of obtained composites were remarkably advanced. With the introduction of 10 wt % end-modified CNC, the tensile strength, Young’s modulus, and storage modulus of the prepared composite increased by 160, 468, and 1041% in contrast with those of the neat NR material. More importantly, this composite retained a high level of elongation at the break (1575%) similar to that of the raw rubber material attributed to the designed covalent linkage and resultant reactive enhancement of end-modified CNCs to the NR matrix.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
·
IF 5.4
Li Wang,Jianlu Qu,Zixuan Yan,Cunhao Li,Xingchu Gong,Wenlong Li
Curcumin (CUR) exhibits broad pharmacological activities, including anti-inflammatory, antibacterial, and antioxidant effects, and shows promising therapeutic potential in diseases such as diabetes and liver injury. However, its poor water solubility and low stability significantly limit clinical application. Conventional nanoemulsion solidification techniques, such as spray-drying and lyophilization, often involve high energy input, drug degradation, and poor redispersibility, making it challenging to achieve both stability and performance. In this study, we developed a novel strategy combining design-of-experiments (DoE) optimized curcumin nanoemulsions (CUR-NE) with fluidized bed coating to systematically enhance solubility and stability. Plackett-Burman design was used to screen key variables, and Box-Behnken design further optimized these factors, revealing that formulation parameters exert a more pronounced effect on particle size and polydispersity index (PDI) than process variables. The optimized CUR-NE exhibited an extremely small droplet size (Z-Ave = 13.48 ± 0.20 nanometers) and uniform distribution (PDI = 0.064 ± 0.013), and maintained a low redispersibility index (109.95 ± 1.18 percent) when coated onto pellets (CUR-Ps). Structural characterization using FT-IR and XRD confirmed negligible drug and excipient interactions and partial amorphization of CUR. Unlike conventional solidification methods, fluidized bed coating significantly improved the storage stability of the nanoemulsion while preserving its excellent solubility. This approach not only provides a new technical pathway for the development of curcumin delivery systems but also offers an innovative reference for the industrial production and application of poorly soluble drugs.
研究领域:
药剂学
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药物递送系统
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纳米技术
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制剂科学
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制药技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2025
·
IF 3.9
Xu Yongjian,Wei Xudong,Deng Wenhuan,Chen Hao
To address the challenge of irreversible aggregation of nanocrystalline cellulose (CNC) after dehydration and to prepare high-concentration redispersible CNC pastes, this study presents an eco-friendly strategy employing maltodextrin (MD) and sodium polyacrylate (PAAS) as synergistic dispersants. MD functions as a “hydrogen bonding inhibitor” whereas PAAS effectively stabilizes CNC suspensions through electrostatic repulsion. Redispersible CNC pastes with varying dehydration levels were successfully prepared via vacuum-assisted concentration. Systematic evaluations of MD/PAAS impacts on Re-CNC colloidal behavior—including the hydrodynamic diameter, particle size distribution, and surface charge (zeta potential) unveiled the identification of four optimal redispersion pathways. Crucially, the concentration-dehydration-rehydration cycle preserved CNC’s intrinsic properties under optimized conditions. Transmission electron microscopy (TEM) analysis confirmed the morphological integrity of CNC, while Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) profiles confirmed retention of chemical functionalities and crystalline structures. The engineered pastes exhibited prolonged dispersion stability (> 30 days without sedimentation). Thermal gravimetric analysis further revealed that MD-stabilized Re-CNC maintained thermal decomposition resistance equivalent to native CNC, with PAAS integration substantially elevating thermal endurance by 18–22%. Ultimately, using redispersed cellulose nanocrystals (Re-CNC) and sodium alginate (SA) as the matrix and curcumin (Cur) as the model drug, a double-network hydrogel, Cur@Re-CNC/SA, was constructed through cross-linking with calcium gluconate. Its drug release performance was comparable to that of Cur@CNC/SA prepared from pristine CNC, verifying the feasibility of the redispersion strategy. Graphical abstract
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DOI
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
·
2024
·
IF 4.5
Minfang Feng,Yuting Tian,Yingying Zhang,Cuiting Yang,Xinhui Peng,Shuai Cen,Mengke Sheng,Zhixun Li,Qing Zhou,Xingxing Dai,Xinyuan Shi
Suspension is the common preparation whose absorption rate is second only to the solution. However, problems like the difficulty in screening excipients and the complicated screening process limit its application to a certain extent. In this study, trimethoprim (TMP) was used as the research object. Compound sulfachlorpyridazine sodium Powder(CSSP) containing TMP was used as the research vector to explore the effects of wetting agent(WA), mixing processes between excipients and drug on the preparation stability from the perspectives of the change of the surface free energy between the drug powder and solvent, the reduction of the particle size of the drug, and the interaction between the drug and the excipients, serving the contact angle, sedimentation volume ratio, re-dispersibility, particle size, and appearance as indicators. In addition to that, taking the number density distribution, mean square displacement (MSD), and van der Waals force (VDW) as indicators, the molecular dynamics (MD) simulation technique was employed to explore the differences in the wetting ability of wetting agents (WAs) and the wetting mechanism of WAs on drug molecules. Suitable indicators were screened to provide new ideas for the initial screening of wetting agents from the simulation level and other solutions in tedious and time-consuming problems of experimental excipients screening.
研究领域:
药学
·
分子动力学
·
材料科学
·
药剂学
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2020
·
IF 4.006
Jiaping Liu,Yaqiong Zhang,Songzhe He,Aimei Zhou,Boyan Gao,Mengyu Yan,Liangli (Lucy) Yu
In this study, a microbial transglutaminase (MTGase)-catalyzed reaction was first optimized to prepare the cross-linked sodium caseinate (MSC). At the optimal condition of MTGase to sodium caseinate mass ratio of 250 U/g and 2 h of reaction time, different concentrations of sodium caseinate (5, 25 and 50 mg/mL) were used to synthesize MTGase-catalyzed cross-linked sodium caseinate (named as MSC-5, MSC-25 and MSC-50, respectively), which were further characterized using fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), circular dichroism spectroscopy (CD) and scanning electron microscopy (SEM). Compared to those of sodium caseinate, MSC exhibited a higher molecular weight and surface hydrophobicity index, different secondary structure and microstructure characteristics. Then, MSC-50 was used as the coating stabilizer for zein nanoparticles and their composite nanoparticles (zein-MSC-50 NPs) exhibited a spherical shape with an average diameter of 240.70 nm, a narrow size distribution and negative surface charge of −23.83 mV at the optimized zein to MSC-50 mass ratio of 1:2. The stability studies indicated that zein-MSC-50 NPs had desirable re-dispersibility, thermal, salt and storage stabilities. These results suggested a possible utilization of MSC as the novel stabilizer of zein-based delivery carriers for encapsulating lipophilic bioactive components in functional foods and pharmaceutical products.
研究领域:
食品科学
·
纳米技术
·
生物技术
·
化学工程
✓ 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）