CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Xie Rui-Hong,Ren Peng-Gang,Hui Jian,Ren Fang,Ren Lian-Zhen,Sun Zhen-Feng
In this study, graphene oxide reinforced regenerated cellulose/polyvinyl alcohol (GO–RCE/PVA) ternary hydrogels were successfully prepared via a repeated freezing and thawing method in NaOH/urea aqueous solution. The effect of GO content on the mechanical properties, swelling behavior, water content of composite hydrogels was investigated. It was found that the mechanical properties of GO–RCE/PVA ternary hydrogels were largely enhanced relative to RCE/PVA hydrogels. With the addition of 1.0 wt% GO, the tensile strength was increased by 40.4% from 0.52 MPa to 0.73 MPa, accompanied by the increase of the elongation at break (from 103% to 238%). Meanwhile, GO–RCE/PVA ternary hydrogels performed the excellent pH-sensitivity, and the higher pH leaded to higher swelling ratio. With 0.8 wt% GO loading, the swelling ratio of GO–RCE/PVA ternary hydrogel was improved from 150% (pH = 2) to 310% (pH = 14). In addition, a slight increase in the water content of the ternary hydrogel was achieved with increasing concentrations of GO. It is believed that this novel ternary hydrogels is a promising material in the application of biomedical engineering and intelligent devices.
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高影响因子
JOURNAL OF POLYMER RESEARCH
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2015
·Vol. 22
·期 11
·1-8
·
IF 1.92
Chen Feng,Kan Ze,Hua Sun,Liu Zhengying,Yang Mingbo
A study has been made on an attempt to further expand the current knowledge in melt processing of cellulose. The basic idea is that a few zinc compounds may remain in the regenerated cellulose by formation of a zinc-cellulose complex and hydrolysis reaction when ZnCl 2 molten hydrates are used as a solvent for cellulose. The chance is that zinc compounds may act as isolation agents to destroy the hydrogen bonding and reduce the crystallinity of cellulose. Interesting results revealed that the raw cellulose and regenerated celluloses in our work showed different structures and other, but specific, thermal behavior, admitting that the melting of cellulose was not detected. The results are preliminary but demonstrate that simply destroying the hydrogen bonding and reducing the crystallinity will promote the dehydration of cellulose at a lower temperature, since the activity of the cellulose hydroxyls would be improved unexpectedly in that condition. It is expected that this study will stimulate some new ideas to make some progress in the melt processing of this material.
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高影响因子
WATER RESEARCH
·
2014
·
IF 5.323
Hongyi Liu,Xiaogang Yang,Yong Zhang,Hangcheng Zhu,Juming Yao
This work presents a synthesis process and flocculation characteristics of an eco-friendly flocculant based on bamboo pulp cellulose (BPC) from Phyllostachys heterocycla . Ployacrylamide (PAM) was grafted onto the BPC by free-radical graft copolymerization in homogeneous aqueous solution. The optimal synthesis conditions of the bamboo pulp cellulose-graft-ployacrylamide flocculant (BPC-g-PAM) and its performance on wastewater treatments were investigated. A UV-based method was used to rapidly determine the degree of substitution (DS) of BPC. The results showed that, under the optimal synthesis conditions, the obtained BPC-g-PAM held a grafting ratio of 43.8% and DS of 1.31. Turbidity removal of the product reached 98.0% accompanying with the significant flocculation and sedimentation in target suspensions. The flocculation mechanism was explored by means of zeta potential method. For negatively charged contaminants, like kaolin clay particles, the BPC-g-PAM could remove the contaminants efficiently via bridging and charge neutralization in acidic or neutral environment.
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高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2013
·Vol. 89
·期 12
·1817-1824
·
IF 2.504
Xianxue Li,Tareque Odoom-Wubah,Huimei Chen,Xiaolian Jing,Bingyun Zheng,Jiale Huang
BACKGROUND Biosynthesis of Ag nanoparticles (AgNPs) utilizing renewable materials and nontoxic chemicals has become highly desirable and is currently receiving tremendous attention. In this study, a facile and cellulose-based approach was developed to biosynthesize AgNPs through tandem hydrolysis of silver sulfate and cellulose under hydrothermal conditions. RESULTS Well-defined AgNPs of about 72.0 nm in size were biosynthesized with 0.30 g of cellulose at 200°C for 10 h. The particle sizes of the as-synthesized AgNPs were positively affected by the reaction temperature and time, but on the contrary were negatively affected by the amount of cellulose employed. The results from Fourier transform infrared spectroscopy showed that the cellulose-hydrolyzed products (saccharides or aldehydes) were accountable for the bioreduction of the Ag ions, and the C = O (C–O) groups in the aldehydes or saccharides played critical roles in capping the AgNPs. Additionally, in the presence of the as-synthesized AgNPs, enhanced surface fluorescence of methyl orange was achieved. CONCLUSION A biological and maneuverable strategy was successfully developed for the synthesis of AgNPs by a hydrothermal route through tandem hydrolysis of silver sulfate and cellulose. Thus, this environmentally friendly method is anticipated to be utilized for the biosynthesis of AgNPs and opens up avenues to prepare other metal nanoparticles from metal sulfates. © 2013 Society of Chemical Industry
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高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2013
·
IF 3.328
Xinyan Dai,Zhu Xiong,Haining Na,Jin Zhu
Chemical effect is mainly utilized to induce the accumulation of epoxide soybean oil (ESO) on the surface of microcrystalline cellulose (MCC) particles as the formation of flexible layer to produce superior toughness of polylactide acid (PLA) composites. MCC is firstly maleated to produce appropriate chemical reactivity with ESO and thus ESO is induced to form a flexible layer around MCC particles by chemical reaction happened in melt-blending, which is proved by the results from XPS and contact angle measurements . This flexible layer increases the interfacial adhesion and provides an easy deformation region. As a result, high toughness is provided. The elongation and impact strength of PLA/ESO/MCC ternary composites can be respectively improved to 38.5% and 31.7 KJ/m 2 . This particular structure also helps to increase plasticization effect leading to a slightly decrease in T g . The whole process elaborates a simple but an effective methodology to improve the toughness of PLA/cellulose composite in virtue of chemical effect. Toughness of PLA/ESO/MCC composites can be also controlled by the degree of chemical reaction (adjusted by the substitution degree of MA on MCC). Fully biodegradable PLA/ESO/MCC composite with high toughness is finally fabricated.
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高影响因子
CARBOHYDRATE POLYMERS
·
2013
·
IF 3.479
Ziyu Qin,Li Ji,Xueqiong Yin,Li Zhu,Qiang Lin,Jinming Qin
Various sodium bacterial cellulose sulfates (SBCS) were prepared via the homogeneous sulfation of bacterial cellulose (BC) with a SO 3 /pyridine (Py) complex in a dimethyl acetamide/lithium chloride solution. The SBCSs were characterized using Fourier transform infrared spectroscopy, X-ray diffraction (XRD), carbon nuclear magnetic resonance spectroscopy, gel permeation chromatography, elemental analyses, and thermal gravimetric analyses. A variety of conditions (including various amounts of SO 3 /Py, temperatures, and reaction times) were utilized to obtain SBCSs with DS values that ranged from 0.10 to 1.50. The XRD profiles indicated that the SBCSs had a cellulose II analog polymorphous structure. The differences between BC and microcrystalline cellulose (MC) were studied in their respective reactions. BC is more reactive than MC in both the sulfation and depolymerization processes. The order of reactivity for C OH is C6 > C2 > C3 for both BC and MC. Cellulose sulfates with DS values >0.31 were soluble in deionized water.
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2015
·
IF 4.529
Hangcheng Zhu,Yong Zhang,Xiaogang Yang,Hongyi Liu,Lan Shao,Xiumei Zhang,Juming Yao
The waste management of used flocculants is a thorny issue in the field of wastewater treatment . To natural cellulose based flocculants, utilization of hazardous cellulose solvent and simplification of synthetic procedure are the two urgent problems needing to be further improved. In this work, a series of natural dicarboxyl cellulose flocculants (DCCs) were one-step synthesized via Schiff-base route. The cellulose solvent (NaOH/Urea solution) was utilized during the synthesis process. The full-biodegradable flocculants avoid causing secondary pollution to environment. The chemical structure and solution property of the DCC products were characterized by FT-IR, 1 H NMR, 13 C NMR, TGA, FESEM , charge density and ζ-potential. Kaolin suspension and effluent from paper mill were selected to evaluate the flocculation activity of the DCCs. Their flocculation performance was compared with that of commercial cationic polyacrylamide and poly aluminium chloride flocculants. The positive results showed that the NaOH/Urea solvent effectively promoted the dialdehyde cellulose (DAC) conversion to DCC in the one-step synthesis reaction. The DCCs with the carboxylate content more than 1 mmol/g exhibited steady flocculation performance to kaolin suspension in the broad pH range from 4 to 10. Its flocculation capacity to the effluent from paper mill also showed excellent.
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高影响因子
COLLOID AND POLYMER SCIENCE
·
2015
·Vol. 293
·期 7
·1915-1922
·
IF 1.865
Yang Hui,Xie Yuan,Han Daxin,Mao Wenqi,Cai Weiwei,Guo Xingzhong
Ethyl cellulose porous spheres (ECPSs) loaded with superparamagnetic iron oxide nanoparticles (SPIONs) have been successfully synthesized via a physical method in oil-in-water (O/W) emulsion. The as-prepared ECPSs possess open pores in the shell and interconnected pores inside the spheres by means of phase separation. The SPIONs with an average size of around 5 nm synthesized by co-precipitation method are added into oil phase precursor in the preparation of ECPSs to synthesize the ECPSs-SPIONs. The loading of SPIONs does not change the morphology of ECPSs, while endows the ECPSs with high ferromagnetic properties at room temperature. The resultant ECPSs-SPIONs can be easily separated from dispersion liquid or driven to specific sites under an external magnet.
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高影响因子
CARBOHYDRATE POLYMERS
·
2013
·
IF 3.479
Yiming Zhou,Shiyu Fu,Liangliang Zhang,Huaiyu Zhan
Superabsorbents based on carboxylated cellulose nanofibrils (CCNFs) and carboxymethyl cellulose-g-poly(acrylic acid-co-acrylamide) were synthesized. A series of experiments were performed to evaluate the influence of factors such as CCNFs amount, solution pH, temperature, salt solution type and concentration on the swelling behaviors of the hydrogels. The water uptake of the hydrogels strongly depended on the CCNF content, the swelling capacity in distilled water increased dramatically from 245.8 to 458.7 g/g with the addition of CCNFs up to 2.5 wt%. Furthermore, the incorporation of CCNFs improved salt resistance properties of the hydrogels with slower deswelling rate and higher water retention capacity at deswelling equilibrium. Besides, the CCNF nanocomposite hydrogels presented better responsive behavior in relation to pH presence and showed an increase in water retention capacity at various temperatures. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were employed to examine the structure and morphologies of the prepared superabsorbent hydrogels.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 130
·期 3
·1524-1529
·
IF 1.395
Chaorong Li,Shunxin Shu,Rui Chen,Benyong Chen,Wenjun Dong
Nanofibers of natural cotton cellulose with a degree of polymerization above 10,000 were prepared by electrospinning; they were then functionalized with a rare-earth nano-oxide material of cerium dioxide (CeO 2 ) by means of the hydrothermal method to obtain the designated properties. The morphology, structure, and properties of the as-obtained nanocomposite fibers were characterized by scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and ultraviolet (UV)–visible spectrophotometry. The results show that hydrothermally grown CeO 2 nanoparticles exhibited a polycrystalline cubic fluorite structure and could be dispersed uniformly on the surface of the cellulose nanofiber. The strong interface and electrostatic interactions between the nanoparticles and nanofibers effectively prevented nanoparticle fall-off. The modified natural cotton cellulose nanofibers showed excellent protection against UV radiation because of the function of the CeO 2 particles. Such cellulose nanocomposite materials could have potential applications in UV protection for data-storage or memory devices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1524–1529, 2013
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高影响因子
ELECTROANALYSIS
·
2015
·Vol. 27
·期 6
·1490-1497
·
IF 2.138
Jiapeng Fu,Zengyuan Pang,Jie Yang,Zhanping Yang,Jianhua Cao,Yang Xu,Fenglin Huang,Qufu Wei
We fabricated a novel hierarchical composite mat composed of electrospun cellulose nanofibers decorated with Ag-doped ZnO (Ag-ZnO) nanoparticles and further demonstrated its potential application as the efficient laccase (Lac) biosensor substrate material. The cyclic voltammograms revealed that the Ag-ZnO/cellulose nanofibrous mat provided an excellent microenvironment for Lac immobilization and benefited direct electron transfer of Lac. The fabricated Lac/Ag-ZnO/cellulose/GCE exhibited a highly sensitive detection of catechol with a wide linear range from 0.995 to 811 µM and a low detection limit of 0.205 µM. The results indicated that Ag-ZnO/cellulose nanofibers were the promising nanostructured materials for the construction of different biosensors.
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高影响因子
CELLULOSE
·
2015
·Vol. 22
·期 4
·2365-2374
·
IF 3.573
Ge Wenjiao,Guo Yanzhu,Zhong Haoquan,Wang Xiaohui,Sun Runcang
In response to the shortage of petroleum resources and the growing need for sustainable development, cellulose-based amphiphilic copolymers have emerged as a new generation of value-added functional nanostructures from biomass resources. In this article, 17 amphiphilic hydroxyethyl cellulose-based graft copolymers with different side chains, including poly(lactide), poly( ε -caprolactone) and poly( p -dioxanone), were synthesized via homogeneous ring opening polymerization in ionic liquid 1-butyl-3-methylimidazolium chloride and characterized by FT-IR, 1 H NMR, thermogravimetric analysis and gel permeation chromatography. The resultant copolymers can self-assemble into micelles with a low critical micelle concentration that varies in the range of 0.03–0.24 mg/ml. TEM observations revealed the obtained micelles had a spherical and well-distributed morphology, and DLS analysis showed the nanoscaled sizes were between 40 and 150 nm. These HEC-based micelles can be used as nano-sized vesicles and have great latent forces in drug delivery systems.
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高影响因子
危险品化学品经营许可证（带存储）