ACS Sustainable Chemistry & Engineering
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2016
·
IF 5.267
Hailong Huang,Xianghui Wang,Hao Ge,Min Xu
Molecularly imprinted magnetic cellulose microspheres (MIP-MCM) of artesunate (Ars) are developed by a surface functional monomer-directing system. MIP-MCM are obtained by coating a layer of MIP on the surface of the cellulose and Fe3O4 composite microspheres. The composite materials are characterized by Fourier transform infrared spectra (FTIR), X-ray powder diffraction (XRD), vibrating sample magnetometry (VSM), UV–vis spectrophotometry (UV), dynamic light scattering (DLS), and magnetic resonance imaging (MRI). They are adsorption-selective to Ars, highly regenerate, and stable in wide pH and temperature ranges. The adsorption of Ars reaches equilibrium within 10 h, and the maximum adsorption quantity is as high as 0.22 mg/mg, much better than previous reports. Through the Langmuir–Freundlich isotherm and pseudo-second-order kinetic model, the adsorption kinetics and thermodynamics of MIP-MCM were studied. The thermodynamic studies suggest that the adsorption of Ars on MIP-MCM is a spontaneous process. MIP-MCM also show rapid magnetic separation and high reusability (retained 90% after five cycles). Thus, it is an efficient method for Ars separation and purification. Furthermore, MIP-MCM are good negative MRI contrast agents with good biocompatibility. Due to these properties, this work offers a new potential application for MIP-MCM in aspects of drug delivery and tracking, disease diagnosis, and therapy.
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高影响因子
MATERIALS LETTERS
·
2017
·
IF 2.572
Xue Yang,Yanjiao Zhao,Hassan Mussana,Mengistu Tessema,Lifang Liu
The chitosan (CS)/cellulose nanocrystal (CNC) (0, 0.2. 0.5, 0.8 and 1 wt%) nanocomposites were applied as modifier, and then deposited on the surface of cotton fabric via a pad-dry-cure method. The morphology, mechanical, hydrophilicity and ultraviolet (UV)-blocking properties of prepared fabrics were carefully investigated. The results showed that CS/CNC could obviously enhance the UV-blocking property of cotton fabric. CS/CNC0.5 fabric exhibited the most excellent UV-blocking property as well as good washing durability after 30 times water laundering, indicating CS/CNC could be used as efficient and durable UV blocker for cotton fabric. In addition, CS/CNC also can increase the mechanical property of cotton fabric; while decrease the hydrophilicity of cotton fabric.
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高影响因子
CELLULOSE
·
2016
·Vol. 24
·期 2
·1017-1029
·
IF 3.195
Su Xiuping,Liao Qian,Liu Lin,Meng Ranju,Qian Zhouqi,Gao Huiying,Yao Juming
Cu 2 O nanoparticle (NP)-functionalized cellulose-based aerogel (Cu 2 O/CBA) with three-dimensional (3D) macroporous structure and abundant active sites was successfully prepared for visible-light photocatalysis via in situ deposition of Cu 2 O NPs on cellulose-based aerogel (CBA). Octahedral Cu 2 O NPs were formed and anchored onto the surface and inner wall of the cellulose matrix, which acted as a microreactor to prevent aggregation and protect the catalytic character of the Cu 2 O NPs. The photocatalytic performance of the Cu 2 O/CBA composite catalysts was evaluated using degradation of methylene blue (MB) as model pollutant. The effects of catalyst dosage, initial MB concentration, and solution pH on MB photodegradation were investigated. Use of 3D macroporous CBA improved the MB adsorption capacity and extended the absorption of visible-light irradiation. In particular, in situ deposition of Cu 2 O in the cellulose matrix enhanced separation of photogenerated electrons and holes via surface-adsorbed molecular oxygen, and consequently the catalytic activity. The photodegradation rate of MB by Cu 2 O/CBA composite catalyst reached 95.79%, much higher than the value of 73.59% for pure Cu 2 O. The photodegradation process on the Cu 2 O/CBA composite catalysts followed an apparent pseudo-first-order kinetic model. The Cu 2 O/CBA composite catalyst was easily recycled and reused, with 80% MB degradation rate retained even after six cycles of irradiation for 30 min each. Such Cu 2 O/CBA composite catalysts can be applied for wastewater treatment utilizing solar radiation.
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高影响因子
RSC Advances
·
2017
·Vol. 7
·期 17
·10463-10468
·
IF 3.108
Weisheng Yang,Liang Jiao,Douyong Min,Zhulan Liu,Hongqi Dai
As a flexible, transparent and sustainable material, cellulose nanopapers will gradually replace traditional plastic materials in “green” electronics. However, it is tedious to prepare nanopapers, and the processes have significant effects on the properties of nanopapers. Herein, after TEMPO oxidation and high pressure homogenization, cellulose nanofibrils (CNFs) were successfully produced from the softwood fibers. Then, the nanopapers were fabricated from cellulose nanofibrils using casting and vacuum filtration, and their properties, such as surface morphology, internal structure and optical properties, were examined. The nanopapers produced by casting have much smoother surfaces than those of the nanopapers prepared by filtration. As a result of the varying degrees of light scattering on the surface, nanopapers prepared by filtration present relatively high optical haze (24.2%) and good transmittance (78%) at 550 nm wavelength, whereas nanopapers produced by casting show relatively low optical haze (2.9%) and excellent transmittance (88%). Therefore, the nanopapers prepared by casting and filtration present unprecedented applications in indoor and outdoor display devices, respectively.
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高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2016
·
IF 3.652
Shiliang Wu,Dekui Shen,Jun Hu,Huiyan Zhang,Rui Xiao
The pyrolytic characteristics of cellulose, cellobiose and glucose were examined by TG-FTIR combined with Py-GC–MS, in order to gain the effect of β -O-4 glycosidic bond on the pyrolysis process. In TG-FTIR analysis, two mass loss peaks were observed for cellobiose and glucose, indicating dehydration in low temperature stage and consequently intensive cracking of glycosidic bond and fragments for cellobiose. The samples were tested in Py-GC–MS at the temperature of 300, 500 and 900 °C according to their mass loss characteristics from TG-FTIR. Formation of furans from cellobiose, which involved the cracking of β -O-4 glycosidic bond, was prominent over other products, compared to that of cellulose and glucose. Four possible chemical pathways for the cleavage of β -O-4 glycosidic bond have been proposed with regard to the formation of furans and anhydrosugars from cellulose. Besides, another two reaction pathways leading to the formation of levoglucosan were also suggested.
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高影响因子
CELLULOSE
·
2016
·Vol. 24
·期 2
·591-607
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IF 3.195
Xiao Guifa,Ding Chunyue,Song Feiyu,Qian Xueren,An Xianhui
A facile strategy for preparation of alkyne-functionalized cellulose fibers with click reactivity is reported herein. Poly(3-ethynylaniline) [poly(3-EA)] with pendant alkynyl groups was obtained by chemical oxidation polymerization of 3-ethynylaniline with ammonium persulfate in low-concentration hydrochloric acid solution at ice-bath temperature and used to generate alkyne-functionalized cellulose fibers in situ from pulp fibres. Successful preparation of alkyne-functionalized cellulose fibers was confirmed by attenuated total reflectance Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The effects of process variables on poly(3-EA) deposition and fiber loss were investigated, and suitable preparation conditions identified. Deposition of poly(3-EA) did not change the crystallinity or hydrophilicity of the cellulose fibers. Poly(3-EA) and alkyne-functionalized cellulose fibers reacted with azides by Cu(I)-catalyzed alkyne–azide 1,3-dipolar cycloaddition. Thus, this in situ chemical polymerization technology provides a new platform for click functionalization of cellulose fibers. Applications of cellulose fibers produced in this way are limited to those without demanding requirements in terms of product strength or color.
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高影响因子
ADVANCES IN POLYMER TECHNOLOGY
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2016
·Vol. 37
·期 3
·869-877
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IF 1.114
Yongkang Bai,Yuejun Liu,Qihua Wang
In this work, a bio-shape memory polymer (SMP) with high performance is prepared by using cellulose acetate (CA) as raw material. The materials exhibit good mechanical properties with tensile strength and elongation at break over 46 MPa and 115%, respectively. With hydrogen bond interaction as physically cross-linked points, the materials also present excellent dual-shape memory properties with shape fixation and shape recovery ratio of about 99% and 96%, respectively. Moreover, the materials show good triple-shape memory effect. The recyclability of the materials is also investigated and the results show that the reclaimed samples still hold high mechanical and shape memory properties. With the intrinsic biocompatibility and biodegradation of CA, the materials could be an attractive candidate for applications in smart biomedical devices. Furthermore, the usage of CA as SMP could expand the view of preparing bio-SMP in future.
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高影响因子
CELLULOSE
·
2017
·Vol. 25
·期 1
·463-471
·
IF 3.417
Long Keying,Cha Ruitao,Zhang Yapei,Li Juanjuan,Ren Fangping,Jiang Xingyu
Cellulose nanocrystals (CNCs) of excellent mechanical properties, high purity, high aspect ratio, and cost-efficient production have drawn many attentions as a new class of reinforcement nanofillers. We chose CNCs as reinforcement nanofillers, which were incorporated in collagen to prepare CNCs/collagen casings by a traditional extruding method. The effects of CNCs on these casings were investigated. The dispersity and compatibility of CNCs within the collagen are rather good. The presence of CNCs can improve the light transmittance, barrier property, tensile strength, Young’s modulus, and thermostability of the CNCs/collagen casings, where collagen might cross-link with CNCs by electrostatic and hydrogen bonding interaction. When the CNCs content is 4 wt%, the water vapor permeability of CNCs/collagen casing reaches the minimum of 0.18 g·mm/h·m 2 ·KPa. That concentration gave the highest light transmittance, and the mechanical properties were optimal. The development of CNCs/collagen casings represents an important potential to extend shelf life by the prevention of lipid oxidation and water loss of sausages.
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高影响因子
CELLULOSE
·
2016
·Vol. 23
·期 4
·2449-2455
·
IF 3.195
Li Zhaoqian,Qiu Jia,Pei Chonghua
Recyclable and transparent nanocomposite films based on bacterial cellulose (BC) and hemiaminal dynamic covalent network polymer (HDCN) have been synthesized by in situ polymerization of 4,4′-diaminodiphenyl ether (ODA) with paraformaldehyde. Transparency and structural and mechanical properties of such nanocomposite films are investigated. It was found that BC/HDCN nanocomposite films exhibits a high optical transparency (86 % at 550 nm). Scanning electron microscopy reveals excellent compatibility of the reinforcement of BC nanofibers and HDCN matrix, which leads to the improvement of 20 and 200 % in tensile strength and storage modulus, respectively, as compared to neat HDCN films. BC hydrogels are readily recoverable from nanocomposite films by the sulphuric acid treatment and ODA monomer is deposited and also recycled.
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高影响因子
RSC Advances
·
2017
·Vol. 7
·期 67
·42113-42122
·
IF 3.108
Bo Wang,Hai-Rong Zhang,Chao Huang,Lian Xiong,Jun Luo,Xin-de Chen
Bacterial cellulose (BC) has great potential to be used as a new filler in reinforced isotactic polypropylene (iPP) due to its characteristics of high crystallinity, biodegradability and efficient mechanical properties. But the compatibility between BC and iPP is poor. The esterification modified BC (CO) and addition of maleic anhydride grafted polypropylene (MAPP) as a compatibilizer were both used to improve interfacial compatibility of iPP and BC to prepare iPP/BC composites, and the non-isothermal crystallization behavior of isotactic polypropylene/bacterial cellulose composites was discussed. The results showed that with the addition of CO or MAPP, the compatibility of iPP/BC composites greatly improved. Moreover, BC addition was found to enhance iPP crystallization due to homogeneous and heterogeneous nucleation effects. In non-isothermal crystallization kinetics, it was found that the Jeziorny method and ϕ–t analysis are more accurate to describe non-isothermal crystallization behavior of iPP/BC composites. The results showed that the non-isothermal crystallization rates increase in the order of iPP/BC2, iPP, iPP/CO2, and M-iPP/BC3, indicating that the compatibility of iPP/BC composites. Moreover, the cooling rate have greatly influence on non-isothermal crystallization behavior of iPP/BC composites.
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高影响因子
ChemPlusChem
·
2016
·Vol. 81
·期 12
·1292-1298
·
IF 2.836
Jian He,Chun-Fai Ng,King Young Wong,Weifeng Liu,Tao Chen
Graphical Cellulose in solar cells : The photostability and moisture stability of CH 3 NH 3 PbI 3 solar cells is significantly improved by ethyl cellulose (EC) incorporation (see figure). The hydrogen bonds between EC and CH 3 NH 3 PbI 3 stabilize the crystal structure, which accounts for the stability improvement. Organic–inorganic hybrid perovskite solar cells have achieved high power conversion efficiencies (PCE) of around 22 %, comparable to conventional silicon and thin-film solar cells. However, the poor stability of the perovskite material is one of the significant drawbacks for its practical application. In moderate humidity, the perovskite hydrates and decomposes within hours or a few days, which deteriorates the device efficiency rapidly. Herein, is demonstrated the moisture stability and photostability of CH 3 NH 3 PbI 3 can be greatly improved through the interaction between ethyl cellulose (EC) and perovskite crystals. It is found that the CH 3 NH 3 PbI 3 film with EC incorporation is stable over 5 days in 60 % relative humidity (RH) under ambient indoor light, whereas the conventional CH 3 NH 3 PbI 3 film without EC is degraded in 1 day. After being stored in 60 % RH under ambient indoor light for 2.5 days, the solar cell with EC incorporation shows a PCE decrement from 14.08 % to 8.21 %, whereas that without EC is nearly entirely degraded (PCE=0 %). Nuclear magnetic resonance (NMR) spectroscopy shows that hydrogen bonding between EC and CH 3 NH 3 PbI 3 accounts for the improved moisture stability by stabilizing the crystal structure.
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PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2016
·
IF 4.219
Jie Hao,Shuyi Xu,Naiyu Xu,Duxin Li,Robert J. Linhardt,Zhenqing Zhang
Microcrystalline cellulose, a major component of cell wall of plants, is one of the most abundant natural materials, but the poor solubility of cellulose limits its applications. Cellulose is a linear glucan with exclusive β 1 ⿿ 4 linkage. Oxidation carried out with TEMPO⿿NaBr⿿NaClO system can selectively oxidize the C6 of glucose residues in cellulose. This modification improves polysaccharide solubility and other physicochemical properties. In this work, the impact of degree of oxidation on solubility, degree of crystallization, thermostability, molecular weight and the structures of the resulting oligosaccharide products of selectively oxidized cellulose were investigated using x-ray diffraction, thermogravimetric analysis, gel permeation chromatography⿿multiple angle laser light scattering and ultrahigh performance liquid chromatography⿿electrospray⿿quadrupole/time of flight⿿mass spectrometry, respectively. The physicochemical properties of selectively oxidized cellulose having different degrees of oxidation were carefully characterized providing a theoretical foundation for the more accurate selection of applications of oxidized celluloses.
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PubMed
高影响因子
危险品化学品经营许可证（带存储）