COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
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IF 3.99
Chaoling Bao,Xiuqiong Chen,Chang Liu,Yue Liao,Yi Huang,Lin Hao,Huiqiong Yan,Qiang Lin
The cellulose nanocrystals (CNCs) synthesized by sulfuric acid hydrolysis are highly hydrophilic and prone to form the agglomerations due to the hydrogen bonding , which limit their applications in the formulations of Pickering emulsions . For this reason, we selected microcrystalline cellulose (MCC) as the raw material for the extraction of CNCs through sulfuric acid hydrolysis and hydrogen peroxide oxidation , and then combined the surfactants of cetyltrimethylammonium bromide (CTAB) and CNCs to prepare the (O/W) Pickering emulsions by high-speed shearing method. The physicochemical properties of the resultant CNCs were evaluated by scanning electron microscopy (SEM), atomic force microscope (AFM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The formed emulsions were characterized by fluorescent microscope (FM). And the effects of the CTAB concentration, pH and ionic strength on the stability of the formed Pickering emulsions were also investigated. Experimental results showed that the sulfuric acid hydrolysis of MCC induced the removal of the amorphous components and the cleavage of the crystalline microfibrils, making CNCs exhibit the curled and rod-like shape with the average hydrodynamic diameter of 460.5 nm (PDI = 0.585), zeta potential of -34.1 mV and the crystallinity index (CrI) of 77.3 %, which revealed good colloidal properties . In addition, the optimal emulsification conditions for CTAB concentration, pH and ionic strength were respectively 0.5 CMC , 11 and 20∼60 mmol/L. On the basis of the above results, the Pickering emulsions stabilized by CTAB/CNCs complex may have potential for large applications in foods, cosmetics and medicines.
研究领域:
食品科学
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材料科学
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化学工程
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2020
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IF 5.162
De-Fa Hou,Zheng-Ying Liu,Ling Zhou,Huang Tan,Wei Yang,Ming-Bo Yang
Cellulose is an abundant feedstock with renewability and biodegradability . However, it is still challenging to manufacture natural cellulose products by environmentally friendly thermoplastic processing methods. Herein, we proposed a green approach for the heterogeneous preparation of thermoplastic cellulose grafted polyurethane (RCP-g-PU) from amorphous regenerated cellulose paste (RCP) via hydroxyl/isocyanate chemistry. First, amorphous RCP was fabricated through dissolving cellulose in sodium hydroxide aqueous solution and regenerating in polyethylene glycol, resulting in the enhancement of the accessibility of hydroxy groups in cellulose chains. Subsequently, a series of thermoplastic RCP-g-PU with the melt flow temperatures ranging from 160 °C to 226 °C were feasibly synthesized by adding hexamethylene diisocyanate into RCP without using other organic solvents . Eventually, the resultant RCP-g-PU can be directly hot-pressed into transparent films with flexibility and foldability. The reported methodology represents a sustainable route to achieve thermoplastic cellulose derivatives .
研究领域:
材料科学
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绿色化学
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2014
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IF 3.916
Guozhi Fan,Chongjing Liao,Tao Fang,Shanshan Luo,Guangsen Song
The acetylation of cellulose using sulfonated Amberlyst 15 as a new and reusable catalyst was investigated. Optimization of the acetylation process was carried out by variation in the amount of added catalyst, acetic acid, and acetic anhydride as well as the reaction conditions, which includes reaction time and reaction medium. Cellulose acetate, with a degree of substitution (DS) value of 2.38 and yield of 54.1%, was obtained under the optimized conditions and characterized using Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis–derivative thermogravimetry (TGA–DTG), and differential scanning calorimetry (DSC). The sulfonated polymer catalyst could be easily recovered by centrifugation after acetylation. Both the fresh and recovered catalysts were characterized by means of FTIR, TGA–DTG, DSC, and scanning electron microscopy (SEM), and the recovered catalyst could be successfully reused without further treatment. It was found that Amberlyst 15 possessed excellent catalytic stability, no significant changes in the DS values, and consistent yields of cellulose acetate observed over four reaction cycles.
研究领域:
化学工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2014
·Vol. 132
·期 1
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IF 1.64
Chongjing Liao,Tao Fang,Shanshan Luo,Guo-Zhi Fan,Guangsen Song
The preparation of partial acetylation of cellulose derived from rice straw was catalyzed by phosphotungstic acid with various numbers of crystal water, and H 3 PW 12 O 40 ·4H 2 O was found to be as effective catalyst. The yield of the cellulose acetate was significantly enhanced by converting cellulose directly isolated from rice straw into microcrystalline cellulose before acetylation. The optimization of the acetylation was investigated by varying the amount of catalyst and acetic anhydride as well as reaction conditions including reaction time and medium, and a degree of substitution (DS) value of 2.29 and yield of 62.9% were obtained under the optimized conditions. The structure and the formation of the acetylated product were confirmed by Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (XRD) technique, the thermal properties were determined by thermal analysis including thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC), and the morphology was observed by scanning electron microscope (SEM). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41212.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2016
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IF 4.219
Sha Deng,Rui Huang,Mi Zhou,Feng Chen,Qiang Fu
Cellulose films with excellent mechanical strength are of interest to many researchers, but unfortunately they often lack the ductility and water resistance. This work demonstrates an efficient and easily industrialized method for hydrophobic cellulose films made of modified microfibrillated cellulose (MFC). Prior to film fabrication, the simultaneous exfoliation and acylation of MFC was achieved through the synergetic effect of mechanical and chemical actions generated from ball milling in the presence of hexanoyl chloride. Largely enhanced tensile strength and elongation at break have been achieved (4.98 MPa, 4.37% for original MFC films, 140 MPa, 21.3% for modified ones). Due to hydrophobicity and compact structure, modified films show excellent water resistance and decreased water vapor permeability. Moreover, optical performance of modified films is also improved compared with the original MFC films. Our work can largely expand the application of this biodegradable resource and ultimately reduce the need for petroleum-based plastics.
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
PubMed
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
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2023
·Vol. 34
·期 9
·3022-3034
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IF 3.4
Xiaonan Fan,Zhenjun Xiong,Jian Li,Jinyou Lin,Xiuhong Li
The petroleum-based materials are widely used in daily life, which are inherently tough to degrade, increasingly polluting the environment and affecting human health. Cellulose fibrous membrane, the ubiquitous, low-cost, and biodegradable material, can serve as a promising substitute. Herein, the biodegradable cellulose fibrous membranes were constructed with cellulose microfibers made from wood particle fibers (WPF) and the mechanical properties were enhanced by introducing the crosslinking system. The cellulose fibrous membrane made of the original WPF showed low tensile strength (0.1 KPa) and elastic modulus (1 MPa). By adding 10 wt% cellulose nanofibrils (CNFs), the prepared cellulose fibrous membrane exhibited an increase in tensile strength (0.525 MPa) and elastic modulus (535 MPa), respectively. To further improve the mechanical properties, the sodium alginate (SA) and Ca 2+ were introduced to crosslink with the CNFs and promote the interaction among SA, CNFs and microfibers, which resulted in a substantial increase in tensile strength (5.62 MPa) and elastic modulus (1660 MPa) due to the formation of the interpenetrating entanglements and anchors. The normalized fracture energy of crosslinked hybrid cellulose fibrous membrane was 100.38 times higher than that of the original WPF membrane and 16 times higher than that of the un-crosslinked cellulose membrane comprising CNFs. This strategy can serve as the foundation for preparing a mechanically enhanced cellulose fibrous membrane via crosslinking, making it possible to replace petroleum-based plastics.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
FOOD CHEMISTRY
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2022
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IF 9.231
Hong Zhu,Jun-Hu Cheng,Ji Ma,Da-Wen Sun
An effective method based on Fe 2+ assisted cold plasma (CP) to pretreat pineapple peel cellulose for the preparation of cellulose nanofibrils (CNF) was proposed in this study. The mechanism underlying Fe 2+ assisted CP pretreatment based on the structural changes of cellulose was investigated. Results showed that the cellulose preabsorbed Fe 2+ , followed by 60 min of CP treatment, and then was nanofibrillated into CNF via ultrasonication. Fe 2+ assisted CP treatment exhibited strong capacity to significantly decrease the degree of polymerization of cellulose and to enhance electrostatic repulsion of fibrils. Furthermore, the roughness and breakage were observed on the surface of pretreated cellulose. The content of inter-molecular hydrogen bonds and average crystallite size (D hkl ) also decreased significantly. The current results provided useful fundamental insights into Fe 2+ assisted CP and cellulose interaction, which should be beneficial to developing new pretreatment methods for disintegrating cellulose into CNF.
研究领域:
材料科学
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生物化学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2022
·Vol. 23
·期 18
·10764
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IF 6.208
Peng Zhu,Luyao Feng,Zejun Ding,Xuechun Bai
Spherical cellulose nanocrystal (CNC), as a high value cellulose derivative, shows an excellent application potential in biomedicine, food packaging, energy storage, and many other fields due to its special structure. CNC is usually prepared by the mixed acid hydrolysis method from numerous cellulose raw materials. However, the pretreatment route in preparing spherical CNC from cellulose fiber is still used when choosing microcrystalline cellulose (MCC) as the raw material, which is not rigorous and economical. In this work, pretreatment effects on the properties of spherical CNC produced from MCC by mixed acid hydrolysis were systematically studied. Firstly, the necessity of the swelling process in pretreatment was examined. Secondly, the form effects of pretreated MCC (slurry or powder form) before acid hydrolysis in the preparation of spherical CNC were carefully investigated. The results show that the swelling process is not indispensable. Furthermore, the form of pretreated MCC also has a certain influence on the morphology, crystallinity, and thermal stability of spherical CNC. Thus, spherical CNC with different properties can be economically prepared from MCC by selecting different pretreatment routes through mixed acid hydrolysis.Keywords:spherical cellulose nanocrystals;pretreatment;microcrystalline cellulose;mixed acid hydrolysis;crystallinity;thermal stability
研究领域:
材料科学
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生物工程
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产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2023
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IF 8.4
Weisheng Yang,Zekai Mei,Shu Feng,Chang Li,Jiaqi Guo,Huiyang Bian,Huining Xiao,Hongqi Dai,Chaoquan Hu,Jingquan Han
Cellulose nanocrystals (CNCs) are clean and sustainable materials that have drawn significant attention in academia and industry because of their unique physicochemical properties. However, realizing economical and environmentally friendly production of CNCs remains a challenge. In this study, we proposed an innovative strategy to fabricate CNCs, which involves the acid hydrolysis pretreatment of wood cellulose fibers using innocuous and recyclable ferric chloride hexahydrate (FeCl3·6H2O). During the molten FeCl3·6H2O treatment, the degree of polymerization (DP) of the cellulose fibers sharply decreased, along with the transformation of cellulose I to cellulose II crystallites. Molten FeCl3·6H2O quickly hydrolyzed cellulose fibers within 5 min at 80 °C, inducing a rapid decrease in the DP from 922 to 196, and the water-insoluble solid (WIS) retention reached 80.1%. CNCs were successfully produced from the mechanical disintegration of the WIS with a low energy input. Hence, the yield of CNCs is consistent with that of the WIS. Interestingly, the CNCs exhibited typical cellulose II crystallites, which were significantly different from those of the cellulose feedstock (cellulose I). Detailed characterization revealed that the CNCs had tunable number-averaged heights of 10.4–26.9 nm and high thermal stability (a maximal weight loss temperature of 327 °C). Most notably, FeCl3·6H2O was easily recycled from the hydrolysate after hydrolysis, with a high recovery of 94.0–94.5 wt %, using simple concentration and crystallization technologies. Thus, this study proposes a novel production technology for CNCs that is both economical and eco-friendly, providing new ideas for clean and large-scale production of CNCs.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
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2026
·
IF 13.2
Xin-rui Xiao,Rui Luo,Jing-hui Yang,Nan Zhang,Yong Wang
Green, renewable, and high-performance dielectric materials is critical for sustainable electronics. Herein, cellulose-based composite dielectric films were synthesized using cellulose nanocrystal (CNC) as a nanofiller and cellulose triacetate (CTA) as the matrix. The results demonstrate that incorporating a small amount of high-modulus CNC (0.3 wt%) reduces structural defects through physical cross-linking and hydrogen bonding between CNC and CTA chains. This interaction acts as a deep charge trap, effectively suppressing carrier migration, while simultaneously increasing the matrix entanglement density and Young's modulus. Consequently, the composite films maintain a optical transmittance of 90%, enhanced thermal stability, and dramatically improved mechanical properties, with tensile strength (50.18 MPa) and tensile modulus (3.62 GPa) increasing by 67.9% and 38.2%, respectively. The breakdown strength is enhanced to 630.68 MV/m, approximately 34.1% higher than that of the pure CTA film (470.32 MV/m). Furthermore, the discharge energy density reaches 4.37 J/cm 3 at 725 MV/m, representing a 1.74-fold increase over that of the pure CTA films, while maintaining an energy efficiency of 70.2% and demonstrating good charge-discharge cycling stability. This study proposes a practical approach toward the design of next-generation dielectric materials that are high-performing, and environmentally sustainable for energy storage.
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
·
IF 7.7
Yujia Liu,Lina Zhang,Qurat ul Ain,Zhangfa Tong
Cellulose acetate (CA) is an important cellulose derivative with a wide range of applications. To adopt a more efficient and environmentally friendly method to synthesize cellulose acetate, a binary ionic liquid mixture of 1-butyl-3-methylimidazole chloride salt (BmimCl) and 1-butyl-3-methyldihydroimidazole phosphate (BmimH 2 PO 4 ) was used. Compared to the conventional methods, this approach didn't require pre-activation of cellulose and the process of homogeneous acetylation proceeded without a catalyst. By simply adjusting the reaction conditions, cellulose acetate with a degree of substitution (DS) in the range of 0.83–3.0 was produced by one-step homogeneous acetylation without hydrolysis. Furthermore, the cellulose acetate film produced by solvent casting exhibited smooth surface characteristics, 95 % transparency, and 57.9 MPa tensile strength. Therefore, this study highlights the importance of using binary ionic liquid mixtures for facile synthesis of cellulose acetate. Due to their excellent transparency and mechanical properties, newly synthesized cellulose acetate films could replace commercial films.
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
PubMed
高影响因子
CELLULOSE
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2025
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IF 4.8
Bai Xiaoyu,Zhou Yuan,Li Jiangtao,Xia Zhaoxia,Wang Zhaojiang,Zhang Qiang,Jiang Yuanzhang,Wang Guixin,Tan Lin,Zhang Yong
In this paper, cellulose acetate (CA) and cellulose nanocrystal (CNC) modified polyvinylidene fluoride (PVDF) membranes were prepared by solution blending and non-solvent induced phase separation methods to improve the hydrophilicity and diafiltration capacity of the membranes. The changes in membrane performance before and after modification were systematically studied through simulated dialysis experiments, antifouling performance tests and biocompatibility analysis. The results show that CA blending and CNC doping will change the morphology and structure of the PVDF membrane, improve its hydrophilicity and permeability, and make it show better filtration capacity and antifouling performance. The modified PVDF membrane has higher clearance and diafiltration efficiency for small molecular solutes urea and creatinine, especially for the middle molecular solute lysozyme, while retaining most of the protein molecules, with a flux recovery rate of more than 95%. The modified PVDF membrane also has good biocompatibility. Bio-based CA and CNCs play an important role in improving the antifouling and diafiltration capacity of PVDF membranes.
研究领域:
材料科学
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生物医学工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）