POLYMERS FOR ADVANCED TECHNOLOGIES
·
2024
·Vol. 35
·期 5
·e6421
·
IF 3.1
Ya-Jing Cao,Xue-Jie Gai,Wei Li,Hai-Hui Liu,Na Han,Xing-Xiang Zhang
Artificial muscles have attracted great attention as actuators and coiled and twisted monofilament actuators are considered the most promising ones. In the present work, the torsional properties of poly(hexamethylene adipamide) (PA66), poly(ethylene terephthalate) (PET), and high-strength PET (HTPET) monofilaments were investigated. Furthermore, cross-linked PET (CPET) monofilaments were melt-spun by adding 1 wt% of 2-dimethoxy-2-phenylacetophenone (ultraviolet (UV) initiator) and triallyl iso-cyanurate (cross-linking agent) in PET chips under UV radiation. The HTPET monofilaments had the highest torsional modulus of 1.1 GPa followed by the PET (0.8 GPa) and PA66 (0.6 GPa) monofilaments. Subsequently, the HTPET monofilaments were subjected to heat treatments under tension. When the heat treatment time was 10 min, the mechanical properties of the HTPET monofilaments also tended to first increase and then decrease with the rise of heat treatment temperature. The molecular arrangement and crystal structure of the HTPET monofilaments were gradually improved with the prolongation of tension heat treatment. The tensile strength and initial modulus of the HTPET monofilaments were 871.4 MPa and 15.8 GPa, respectively. The mechanical properties of the CPET monofilaments first increased and then decreased with the increase of the drawing ratio. When the drawing ratio was 10, the CPET monofilament had a tensile strength of 717.2 MPa, an initial modulus of 16.7 GPa, and a maximum torsional modulus of 1.3 GPa. Therefore, both heat treatment and cross-linking increased the mechanical strength of the PET monofilaments. CPET and HTPET are possible to be used as artificial muscles.
研究领域:
材料科学
·
高分子物理
·
纺织工程
·
生物医学工程
·
智能材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 24
·11370-11376
·
IF 9.931
Qinglong Fu,Pan Yang,Jingchuan Wang,Hefang Wang,Lijun Yang,Xiaochong Zhao
Simple, safe and economic methods to prepare Ni nanofibers are required for their practical application. Herein, an in situ vacuum thermal reduction strategy is proposed to synthesize Ni nanofibers on a large scale, which involves electrospinning of a nickel acetate/polyvinylpolypyrrolidone/ethyl cellulose (NiAc/PVP/EC) precursor solution, followed by vacuum thermal treatment. Characterization of the morphology and microstructure reveals that the as-prepared Ni nanofibers are composed of nano-size Ni grains and possess a large surface area. Moreover, it has been demonstrated that the content of EC is closely related to the size of Ni grains and thus the surface area of Ni nanofibers. On account of their high specific surface area, the as-prepared Ni nanofibers exhibit efficient catalytic properties for H2 generation from hydrous hydrazine in an alkaline solution.
研究领域:
材料科学
·
纳米技术
·
催化化学
·
能源材料
·
物理化学
✓ 已验证
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2024
·Vol. 45
·期 11
·2400030
·
IF 4.2
Bo Xu,Jin Yang,Yinghe Yang,Jiping Yang,Zhijian Wang
Mechanochromic polymers can change their color in response to external force and have shown promising applications in stress sensing and failure warning. They are usually obtained as thin films or bulky specimens. The mechanochromic fibers, which can be used to make smart fabrics, have been seldom reported due to the lack of efficient fabrication techniques. In this work, a general method using photo-polymerization of microgel solution in a template tube to produce mechanochromic hydrogel fibers is reported. The obtained hydrogel fibers can generate visible and fluorescent color changes upon deformation. The diameter of the mechanochromic fibers can be easily adjusted by using different template tubes. The mechanochromic fibers can be fabricated as long as 1 m. By reducing the fiber diameter or increasing the microgel concentration, the mechanical properties of the mechanochromic fibers can be improved, leading to more obvious mechanochromic behavior. The polymethacrylate (PMA) is further used to coat the hydrogel fibers, prevent the loss of water in the fibers, and increase the storage time. The mechanochromic fibers with multiple fluorescent colors are further fabricated by utilizing different microgel solutions. This work provides an easy and effective method to fabricate mechanochromic fibers with different color change abilities.
研究领域:
高分子材料科学
·
生物医学工程
·
柔性电子
·
智能响应材料
·
纤维科学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2016
·Vol. 24
·期 2
·863-870
·
IF 3.195
Chen Haizhen,Chen Jing,Teng Na,Na Haining,Zhu Jin
Residual ethanol was used as an activation agent to control the status of corn cellulose (CN cellulose) solution and thereby the morphology of CN cellulose fibers after electrospinning. A suitable amount of ethanol could combine with the CN cellulose chains to reduce their ionic absorbance, improving the migration ability of ions in the cellulose– N , N -dimethylacetamide (DMAc)/LiCl–ethanol system. As a result, the entanglement of the molecular chains of CN cellulose in solution was reduced. Excess ethanol reduced the migration ability of ions and enhanced the strong entanglement of CN cellulose in solution. By thus adjusting the status of the CN cellulose solution, the fiber morphology and diameter distribution after electrospinning could be controlled. Based on the experimental results, this approach represents an important and effective approach using ethanol as an activation and adjusting agent for CN cellulose to achieve formation of high-quality electrospun fibers.
研究领域:
高分子科学
·
材料科学
·
纤维工程
·
生物材料
·
纳米技术
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2020
·
IF 4.244
Xiuyu Liu,Yan Jiang,Lijun Wang,Xueping Song,Chengrong Qin,Shuangfei Wang
This study explores the possibility of producing tunable cellulose nanofibers (CNFs) with a wide range of size and properties from sugarcane bagasse in an energy-efficient manner, which is very meaningful for specific application of CNFs. The bleached bagasse kraft pulp was subjected to endoglucanase pretreatment with a wide range of enzyme dosage followed by mechanical grinding to obtain size-tunable CNFs. The size distribution and structural characteristics of CNFs, energy consumed during the CNF production process, and properties of CNF films were systematically investigated as a function of the enzyme dosage applied in the pretreatment. The results showed that endoglucanase-assisted mechanical grinding was able to produce CNFs with controllable length (298–4500 nm) and diameter (9–26 nm), meanwhile improving CNF yield and energy-efficiency. The controllable range of CNF length was extremely wide based on our best knowledge. The optical performance and mechanical properties of the prepared CNF films could be effectively tuned by regulating the structural characteristics of the CNFs. Moreover, all the as-prepared CNFs retained high thermal stability. The tailor-made CNFs from sugarcane bagasse are expected to provide compatibility with various CNF-related applications.
研究领域:
材料科学
·
纳米技术
·
生物质转化
·
可再生资源
·
高分子材料
✓ 已验证
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2022
·
IF 9.93
Qiaomu Zheng,Chen Li,Facheng Song,Bei He,Wenting Li,Zhengwu Jiang
Secondary hydration is the main driving force of autogenous self-healing and directly impacts the closure of cracks in damaged cementitious materials . In fiber-reinforced cement composites , secondary hydration also dominates the regeneration of the fiber-matrix interface during the self-healing processes. As an important factor influencing the cement hydration , silica fume (SF) addition can be crucial to the self-healing performance of cementitious materials and composites. In this paper, the effect of SF on the autogenous self-healing of ultra-high-performance fiber-reinforced concrete was investigated. With a ≥20% SF addition, the secondary hydration the cement matrix adjacent to the cracks was accelerated. The dissolution of amorphous silica and the formation of Si-containing healing phases was observed. These effects predominated the closure of the mouth and the inner part of the cracks. SF addition also enhanced the regeneration of fiber-matrix interface by promoting the growth of self-healing products in these areas. The closure of cracks and the regeneration of fiber-matrix interface are both responsible for the restoration of flexural properties.
研究领域:
建筑材料
·
水泥基复合材料
·
土木工程材料
·
自修复材料
·
结构工程
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Chao Zhong,Chunming Wang,Fengxue Wang,Honghua Jia,Ping Wei,Yin Zhao
Cellulose isolation, a promising way for lignocellulosic biomass utilization, is always restricted by the poor solubility of cellulose. In this paper, tetra-n-methylammonium hydroxide (TMAH) was confirmed to be capable of readily dissolving/regenerating cellulose without chemical modification at room temperature. Meanwhile, cellulose isolation from lignocellulosic biomass by initially dissolving the biomass in TMAH followed by cellulose precipitation was proposed, and the isolated substance with average cellulose purity of 92.1 ± 0.3% could be obtained throughout this process under the optimum conditions: temperature 52 °C, time 60 min, and loading ratio of TMAH/biomass ( w / w ) 7.2:1. Besides, high efficiency cellulose isolation (i.e. >70% cellulose purity) could be continuously remained during 4-round cycles by using the recycled TMAH solvent without distinct activity loss.
研究领域:
生物质化学
·
绿色溶剂
·
天然高分子
·
可持续材料
·
生物精炼
✓ 已验证
DOI
高影响因子
CARBON
·
2022
·
IF 11.307
Xu Zhao,Jizhen Zhang,Ke Lv,Na Kong,Yanqiu Shao,Jinlong Tao
Mechanically strong and electrically conducting fibers, particularly those with high specific capacitances, are promising fiber-shaped electrodes for fiber- and textile-based energy storage devices like fiber-shaped supercapacitors (FSCs). However, a high loading of fillers or bridging agents is commonly required to fabricate fiber electrodes with good mechanical strength , which compromises electrical conductivity and energy storage performance. Herein, an easily scalable wet-spinning strategy is reported to fabricate multifunctional Ti 3 C 2 T x MXene/carbon nanotubes (MXene/CNT) hybrid fibers from a harmonious mixture of MXene and CNT in water and using acetic acid as a coagulation bath . The hybrid fiber achieved high strength (61 ± 7 MPa), good conductivity (1142.08 ± 40.04 S cm −1 ) and excellent energy storage performance (∼295 F g −1 at 5 mV s −1 ) at a very low CNT content of ∼1 wt%. When CNT loading increased to ∼9 wt%, the maximum strain at broken reached 161 ± 19 MPa and conductivity further increased to 1715 ± 22 S cm −1 . The excellent mechanical performance allows hybrid fibers to be knitted into textiles for energy storage textiles. The assembled FSCs exhibit energy and power densities of ∼6.08 mW h cm −3 and ∼6440 mW cm −3 , respectively. The excellent performance of MXene/CNT fiber and good feasibility for scalable production will open up new opportunities for the development of wearable and textile-based devices in the near future.
研究领域:
材料科学
·
纳米科技
·
能源存储
·
纺织电子学
·
高分子物理
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Hui Li,Lincai Peng
To confer cellulose fibers antimicrobial and antioxidant activities, chitosan (CS)/lignosulfonates (LS) multilayers were constructed on fibers surfaces through layer-by-layer deposition technique. The formation of CS/LS multilayers on cellulose fibers surfaces was verified by X-ray photoelectron spectroscopy (XPS) and zeta potential measurement. The surface morphologies of CS/LS multilayers on fibers surfaces were observed by atomic force microscopy (AFM). The results showed that characteristic element (i.e. N and S element) content increased with increasing bilayers number, the surface LS content increased linearly as a function of bilayers. Zeta potential of modified fibers was inversed after deposition of each layer. AFM phase images indicated that the cellulose microfibrils on fibers surfaces were gradually covered by granular LS aggregate. The antimicrobial testing results demonstrated that CS/LS multilayers modified fibers with CS in the outermost layer exhibited higher antimicrobial activity against Escherichia coli . The antioxidant testing results showed that antioxidant activity of CS/LS multilayers modified fibers was better than that of original fibers under the same oxidation conditions.
研究领域:
高分子材料
·
表面科学
·
生物医学工程
·
功能材料
·
纳米技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2017
·
IF 3.671
Ping Shao,Ben Niu,Hangjun Chen,Peilong Sun
Edible packaging films using polymer for food preservation have been developed for a long time. In this study, the effects of different concentrations (0.5%, 1%, 1.5%, w/v) of tea polyphenols incorporated into pullulan-Carboxymethylcellulose sodium (Pul-CMC) solutions on electrospun nanofiber films were evaluated. The fiber size distribution was characterized by scanning electron microscopy. The morphological features of nanofibers were modulated through adjusting process parameters (e.g. concentration of polymer solution, applied voltage and feeding rate). Increasing the applied voltage from 19 to 21 kV and the feed rate from 0.36 to 0.6 mL/h leads to a reduction in mean fiber diameter. Fruit packaging potential was evaluated using strawberry. The pullulan-CMC-TP nanofibers significantly decreased weight loss and maintained the firmness of the strawberries, and improved the quality of the fruit during storage. The findings demonstrate a facile packaging route to improve food sustainability and reduce waste.
研究领域:
食品科学
·
材料科学
·
高分子化学
·
农产品贮藏与加工
·
功能食品
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Shaojie Zhang,Chao Yu,Na Liu,Yun Teng,Cuiyu Yin
In this study, cellulose pulp and urea were used to synthesize cellulose carbamate (nitrogen content reaches 4.5%) by low-cost and environmentally friendly solid-liquid phase method. Cellulose carbamate fluid was prepared by using sodium hydroxide aqueous solution as solvent. The fluid was regenerated and formed in a coagulation bath , and finally a regenerated cellulose membrane with high transparency and separation ability was obtained. The simple chemical treatment of cellulose not only greatly increased the mass fraction of cellulose dissolution (It has reached 15%) and retains the original crystal form and thermal stability of cellulose. The surface of the membrane was relatively dense, and the inside has regular microchannel . The factors affect the transparency and water flux of regenerated cellulose membranes were discussed by orthogonal experimental range analysis. The ability of the regenerated cellulose membrane to reject dyes was tested. The results showed that the rejection of methyl blue and congo red reached 100%, and the rejection rate of methyl orange reached 60%. The oil/water separation ability and the anti-pollution ability of the regenerated cellulose membrane were tested. The oil/water separation effect reached 100%. This membrane may have application prospect in water treatment, biotechnology.
研究领域:
材料科学
·
环境工程
·
膜技术
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2020
·
IF 6.444
Baowei Qiu,Tong Sun,Muxuan Li,Yang Chen,Shengtai Zhou,Mei Liang,Huawei Zou
The interface performance of carbon fiber (CF) reinforced polymer composites (CFRPs) is one of the key factors that affect their properties. In order to improve the interface adhesion between CF and epoxy (EP), a green method is proposed. Carboxymethyl cellulose (CMC) and graphene oxide (GO) are introduced to the CF surface through the hydrogen bonds, and they can form high micromechanical interlocking composite architectures, which can enhance the micromechanical interaction in the interface of CF and EP. It is found that CMC and GO can significantly improve the interfacial shear strength (IFSS) and interlaminar shear strength (ILSS) of EP/CF composite. This means that it has great potential to improve the interface of CFRPs and strengthen their performance by natural cellulose fibers. This modification method does no harm to CF and is environmental friendliness, which lays a research foundation for using natural cellulose to enhance the interface performance of CFRPs.
研究领域:
复合材料科学
·
高分子材料
·
界面工程
·
纳米材料
·
绿色制造
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）