CELLULOSE
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2019
·Vol. 26
·期 7
·4345-4355
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IF 3.917
Zhao Yongsheng,Dang Wanbin,Ma Qiong,Zhu Yanling
Abstract Nanofibrillated cellulose (NFC) has been widely used in bio-composites and plays a critical role of interface phase in determining the final physical properties. However, it remains difficult to directly observe NFC and its network-like phase within its related composite. Herein, we report a facile and low-cost approach to visualize three-dimensional (3D) distribution of NFC and its interfacial morphology with confocal laser scanning microscopy. In this work, coumarin-3-carboxylic acid (C3) was chemically linked with TEMPO-oxidized nanofibrillated cellulose (TNFC) via amidation process with the aid of ethylenediamine, leading to the formation of fluorescent labelled nanocellulose (TNFC-C3). TNFC-C3 was then compounded with poly(vinyl alcohol) (PVA) as a reinforcing nanofiller because of abundant molecular hydrogen-bonding interactions. The spatial distribution and interfacial bonding characteristics of TNFC in composites were investigated. Fluorescence scanning shows a clear 3D network structure of TNFC-C3 in TNFC-C3/PVA composite. More importantly, TNFC-C3/PVA composites show increased mechanical strength from 7.5 to 23.2 MPa with the increase of TNFC-C3 content, indicating that a small number of C3-grafting result in high-quality of fluorescence resolution without sacrificing molecular interactions and reinforcing effect. Graphical abstract
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高影响因子
Journal of Nanomaterials
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2019
·
IF 2.233
Hui Zhang,Jiangying Zhu,Yanqiang Hu,Aonan Chen,Liang Zhou,Hui Gao,Yamei Liu,Shengquan Liu
A novel cellulose/TiO2/β-CD hydrogel with high photocatalytic antibacterial activity and sustained release of drug was prepared. TiO2 sol with a diameter of about 9 nm in this hydrogel was the photoantibacterial agent. β-CD can significantly enhance photoantibacterial activity and the sustained-release effect of this hydrogel. The structure and property of this hydrogel composite were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Escherichia coli and Staphylococcus aureus were selected as model bacteria to evaluate the antibacterial activity of the composite hydrogel under natural light irradiation and darkness, respectively. The in vitro release experiment used curcumin as a model drug in PBS buffer solution. The influence of β-CD on the antibacterial activity and sustained-release effect of the composite hydrogel was investigated. The results showed that the hydrogel composite presented a good photoantibacterial property, while the antibacterial activity can be neglected under the condition of no light. The complete release of curcumin from the composite was achieved after 120 h. Therefore, the hydrogel system has the characteristics of low cost and high effect, which could be used for an antibacterial sustained-release material.
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高影响因子
ADVANCES IN POLYMER TECHNOLOGY
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2019
·
IF 2.663
Quan Ma,Xingzhong Zhang,Qianwen Shi,Yan Li,Bin Li,Shilin Liu
In this work, we presented a facile pathway to fabricate polyanionic cellulosic microparticles by selective oxidation with sodium periodate firstly, followed by grafting sodium bisulfite to the 2,3-dialdehyde cellulose particles. The obtained polyanionic cellulosic microparticles with the particle size of 2-4 μm had increased stability in water, and it had pH responsiveness. Moreover, the polyanionic cellulosic microparticles had excellent film-forming property, and the tensile strength of the film formed from pristine cellulose particles was about 40 MPa, and it increased to 64 MPa for the film formed from SRC-50 particles. Furthermore, the polyanionic cellulosic microparticles had certain reduction ability, and it could be used as coating to cover the surface of fruits or vegetables, and it could prevent the discoloration of the fresh-cut potato. The cellulose based particle coating with excellent antibrowning capacity, biocompatible, and environmentally friendly characteristics would be attractive for the applications in packaging material for food preservation.
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高影响因子
CARBOHYDRATE RESEARCH
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2019
·
IF 1.873
Zhe Tang,Jianhui Su
High efficiency conversion of cellulose to 5-hydroxymethylfurfural (HMF) remains a challenge today. A simple solid acid catalyst Boehmite (γ-AlOOH) with high hydrothermal stability was prepared and used as sole catalyst for the direct conversion of cellulose into HMF in mixed reaction solvents of ionic liquid 1-buthyl-3-methylimidazolium chloride (BmimCl) and dimethyl sulfoxide (DMSO). This was aimed at developing an efficient and inexpensive catalyst for the production of HMF. The effects of factors such as water, solvent, catalyst load, temperature and reaction duration were investigated. An impressive HMF yield of 58.4% with 97.2% cellulose conversion was obtained at 160 °C after 2 h. More importantly, the catalyst γ-AlOOH was reused several times without loss of its catalytic properties. After five reaction runs, an HMF yield of 47.8% with 91.0% conversion was also obtained. In addition, the catalyst γ-AlOOH displayed excellent catalytic effects on the degradation of other carbohydrates. High yields of HMF from other carbohydrates such as glucose (61.2%), starch (62.7%) and inulin (70.5%) were achieved using γ-AlOOH as the catalyst. The proposed catalytic method shows a promising potential for HMF preparation, especially for industrial-scale HMF production from renewable bioresources.
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PubMed
高影响因子
ACS Applied Materials & Interfaces
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2019
·
IF 8.456
Jianming Yang,Shaobing Xiong,Tianyi Qu,Yuexing Zhang,Xiaoxiao He,Xuewen Guo,Qiuhua Zhao,Slawomir Braun,Jinquan Chen,Jianhua Xu,Yanqing Li,Xianjie Liu,Chungang Duan,Jianxin Tang,Mats Fahlman,Qinye Bao
The fast evolution of metal halide perovskite solar cells has opened a new chapter in the field of renewable energy. High-quality perovskite films as the active layers are essential for both high efficiency and long-term stability. Here, the perovskite films with enlarged crystal grain size and decreased defect density are fabricated by introducing the extremely low-cost and green polymer, ethyl cellulose (EC), into the perovskite layer. The addition of EC triggers hydrogen bonding interactions between EC and the perovskite, passivating the charge defect traps at the grain boundaries. The long chain of EC further acts as a scaffold for the perovskite structure, eliminating the annealing-induced lattice strain during the film fabrication process. The resulting devices with the EC additive exhibit a remarkably enhanced average power conversion efficiency from 17.11 to 19.27% and an improvement of all device parameters. The hysteresis index is found to decrease by three times from 0.081 to 0.027, which is attributed to suppressed ion migration and surface charge trapping. In addition, the defect passivation by EC significantly improves the environmental stability of the perovskite films, yielding devices that retain 80% of their initial efficiency after 30 days in ambient air at 45% relative humidity, whereas the pristine devices without EC fully degrade. This work provides a low-cost and green avenue for passivating defects that improves both the efficiency and operational stability of perovskite solar cells.
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PubMed
高影响因子
CELLULOSE
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2019
·Vol. 26
·期 6
·3747-3762
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IF 3.917
Xing Xiao-Yan,Gu Lin,Jin Yu,Sun Rui,Xie Meng-Yun,Wu Qing-Yun
Abstract Cellulose triacetate (CTA) porous membranes were firstly prepared by the combined nonsolvent-thermally induced phase separation (N-TIPS) method. Dimethyl sulfone (DMSO2) and polyethylene glycol (PEG400) were respectively chosen as the TIPS solvent and additive of CTA, while water was used as the NIPS nonsolvent. Their Hansen solubility parameters were analyzed to understand the solution thermodynamics. Detailed investigation was applied on the effects of the polymer concentration, the coagulation bath temperature and the coagulation bath composition on the CTA porous membranes. It is found that both NIPS and TIPS effects simultaneously exist and compete with each other, and further affect the membrane morphology and performance. The NIPS effect can be promoted by lowering the CTA concentration or elevating the coagulation bath temperature, resulting in figure-like macropores and porous top surface. The obtained CTA porous membranes show a water flux as high as 2002.9 ± 55.2 L/m 2 h. On the contrary, the TIPS effect becomes the dominant factor, and leads to the symmetric sponge-like pores, which facilitate to enhance the mechanical properties. Besides, CTA porous membranes present large surface pore size as well as low fraction of figure-like macropores as increasing the DMSO2 content in the coagulation bath. These CTA porous membranes with excellent water permeability and mechanical strength are promising candidates for microfiltration or the porous substrates of thin film composite membranes. Graphical abstract
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Journal of Materials Chemistry A
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2019
·Vol. 7
·期 12
·7033-7041
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IF 10.733
Ming-Bang Wu,Chao Zhang,Jun-Ke Pi,Chang Liu,Jing Yang,Zhi-Kang Xu
There is an increasing demand for anti-oil materials applicable in the efficient separation of crude oil from oil-in-water emulsions and oil/water mixtures for oily water treatment and oil spill remediation. Most of the reported superhydrophilic materials are able to repel model oils, but are still easy to be adsorbed and fouled by crude oil with high viscosity and strong adhesive properties. Herein, we report cellulose nanocrystals (CNCs) for fabricating nanopapers and nanocoatings with high anti-crude oil characteristics. These CNCs are composed of cellulose chains densely and rigidly arranged in a crystalline state, which rigorously restricts the motions of the hydrophilic groups on the material surfaces. They show more stable water binding affinity and lower underwater adhesive force than other super-hydrophilic materials. Therefore, the nanopapers and nano-coatings are capable of eliminating oil contamination from their surfaces not only in the water-wetted state, but also in the dry state. The nanopapers fabricated by vacuum-filtration can effectively separate surfactant-stabilized crude oil-in-water emulsions. The meshes assembled with nanocoatings are useful for the separation of crude oil/water mixtures with an extremely high water flux up to 35 000 L m−2 h−1. Meanwhile, the CNC-based nanomaterials show excellent anti-crude oil properties, no water flux decline, good pH stability and high salt resistance. All these characteristics make them potentially applicable to the remediation of crude oil spills on offshore seawater.
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高影响因子
FOOD HYDROCOLLOIDS
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2019
·
IF 5.839
Qi Li,Bing Xie,Yixiang Wang,Yanting Wang,Liangcai Peng,Yan Li,Bin Li,Shilin Liu
For high value utilization of energy crops, in this work, a high stable O/W Pickering emulsion had been prepared successfully by using cellulose nanofibrils (CNFs) obtained from Miscanthus floridulus straw (MFS). The effect of high pressure homogenization time on the physicochemical properties of the resulted CNFs had been investigated. The obtained CNFs had high surface activity and could spontaneously diffuse to the interface of the O/W phase. The particle adsorption kinetics of CNFs was characteristic of soft particles or Pickering emulsifiers, and the adsorption was irreversible. Therefore, stable oil-in-water Pickering emulsion was obtained by using the CNFs as particle emulsifiers, and the emulsion stabilized by CNFs with only 0.15 wt% exhibited outstanding stability. Moreover, the environmental factors, such as pH values, ionic strength, and temperature had little influence on the stability of the emulsion. All the results indicated that CNFs exhibited promising interfacial activity and powerful emulsifying ability. Owing to the flexible shape of the CNFs, it was concluded that MFS as a kind of energy crop was a promising source to obtain the CNFs for the fabrication of novel food-grade Pickering emulsions.
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高影响因子
Journal of Materials Chemistry C
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2019
·Vol. 7
·期 24
·7411-7417
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IF 6.641
Lin Chu,Xueting Zhang,Wenbin Niu,Suli Wu,Wei Ma,Bingtao Tang,Shufen Zhang
Utilizing biomass materials to construct photonic bandgap materials has attracted increasing attention due to their environmental friendliness. In this work, we introduced biodegradable cellulose acetate to the interstice of hollow silica 3D photonic crystals (PCs) for building hollow silica opals/cellulose acetate nanocomposite films. In the films, the hollow silica 3D PCs offered well-ordered arrays for producing structural colors. Cellulose acetate with excellent film forming ability served as a matrix endowing the PCs frameworks with mechanical stability, including flexibility, robust tensile strength and the ability of repetitive bending. The prepared colored composite films possessed high transparency and can work as anti-counterfeiting labels for banknotes when patterned by a facile mask method. Compared with other reported PCs which are responsive to external stimuli in the field of anti-counterfeiting, these films have the advantage of quick color-transparency switching just by changing the viewing angle. Except for application in security materials, the colored composite films also showed potential as package materials due to their biodegradability.
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高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 8
·5065-5074
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IF 3.917
Hou Ting,Guo Kechun,Wang Zhongguo,Zhang Xiong-Fei,Feng Yi,He Ming,Yao Jianfeng
Self-standing and flexible regenerated cellulose membranes were fabricated by using a facile ZnCl 2 /CaCl 2 /cellulose dissolution system. The filtration experiments of the membranes were conducted by using methyl orange and Congo red as water contaminations. To improve the selectivity and stability, the crosslinkers of glutaraldehyde and polyvinyl alcohol were introduced to the membrane network. The best performance was observed over glutaraldehyde and polyvinyl alcohol crosslinked cellulose (P-G-RC) membrane with a Congo red rejection rate of 99.9% and a methyl orange rejection rate of 93.5%. The suitable pore radius (0.67 nm), low root-mean-square roughness (2.9 nm) and abundant hydroxyl groups were considered as the primary reasons contributed to the separation behavior. Furthermore, the P-G-RC membrane displayed excellent stability and reusability during the filtration tests.
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高影响因子
CARBOHYDRATE POLYMERS
·
2019
·
IF 6.044
Guifa Xiao,Ying Wang,Hui Zhang,Liheng Chen,Shiyu Fu
Facile strategy to construct a cellulose nanocomposite hydrogel with self-healing and biocompatible properties is reported by crosslinking dialdehyde cellulose nanocrystals with acylhydrazine-terminated polyethylene glycol via dynamic reversible acylhydrazone for the first time. The effects of process variables on gelation time, mechanical strength and self-healing efficiency of hydrogels were investigated. It was found that gelation time shortened from hours to seconds by adjusting gelator and catalyst concentration. Tensile and compressive strength of hydrogel could reach 141 K Pa and 580 K Pa at 20.1% gelator concentration, respectively. Interestingly, the as-prepared hydrogel presented excellent self-healing ability without additional stimuli whose healing efficiency was higher than 90% even at higher gelator concentration. Furthermore, Cytotoxicity test showed that cell viability almost reached 100% after culturing with hydrogel, which revealed the hydrogel was biocompatible.
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PubMed
高影响因子
POLYMER
·
2019
·
IF 3.771
Jie Chen,Fushan Chen,Yahui Meng,Shuangfei Wang,Zhu Long
The pursuit of sustainable plastic packaging materials stimulates the development of new materials based on renewable resources and efficient fabrication methods. In this study, thermoplastic hydroxypropyl starch (TPS) as a matrix and oxidized microcrystalline cellulose (MCC) as a reinforcing agent were used to prepare water-soluble composite films via a hot-compression molding technique. As-prepared composite films were disintegrated in water in approximately 60 s, which could potentially reduce plastic pollution in the environment. In addition, MCC was treated to enhance the tensile strength of composite films, with a remarkable increase of ∼249.42%. The composite films are composed of renewable, biodegradable, and environment-friendly materials, and the fabrication process is environmentally benign, highly efficient, cost-effective, and easy for scaling up. The new composite films can be used as a renewable water-soluble material for industrial applications.
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高影响因子
危险品化学品经营许可证（带存储）