Small
·
2024
·Vol. 20
·期 33
·2400482
·
IF 13
Wei Liu,Xi Yang,Guilong Yan,Li Wang,Jingjuan Lai,Zhenyu Li,Chunxia Zhao,Dong Xiang,Hui Li,Yuanpeng Wu
Humidity-responsive materials hold broad application prospects in sensing, energy production, and other fields. Particularly, humidity-sensitive, flexibility, and water resistance are pivotal factors in the development of optimized humidity-responsive materials. In this study, hydrophobic linear polyurethane and hydrophilic 4-vinylphenylboronic acid (4-VPBA) form a semi-intercross cross-linking network. This copolymer of polyurethane exhibits excellent humidity-sensitive, mechanical properties, and water resistance. Its maximum tensile strength and maximum elongation can reach 40.56 MPa and 543.47%, respectively. After being immersed in water at various temperatures for 15 days, it exhibited a swelling ratio of only 3.28% in water at 5 °C and 9.58% in water at 70 °C. While the presence of 4-VPBA network imparts humidity-sensitive, reversible, and multidirectional bending abilities, under the stimulus of water vapor, it can bend 43° within 1.4 s. The demonstrated material surpasses current bidirectional humidity actuators in actuating ability. Based on these characteristics, automatically opening waterproof umbrellas and windows, as well as bionic-arms, crawling robots, and self-propelled boats, are successfully developed.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER COMPOSITES
·
2023
·
IF 5.2
Yu Cao,Zhanxin Liu,Jin Jiang,Ping Song,Shuyang Shao,Hui Zhao,Zhi Wang
Benzoxazine has aroused a lot of research interest because of its high mechanical performance and excellent thermal stability in polybenzoxazines. However, it suffers from its high curing temperature and long curing time, which necessitate resolution. This study addresses this issue by employing a surface-modified fly ash-assisted microwave curing method to achieve ultra-fast benzoxazine curing within 15 min. The impact strength of the resulting cured product displayed an increasing-then-decreasing trend with the addition of fly ash, reaching a maximum impact strength of 18.71 ± 1.20 kJ/m 2 at a 3% fly ash content. This value is 113.3% higher than the impact strength of pure PBA-a. Additionally, when using the same amount of fly ash, the microwave-cured product exhibited a flexural strength of up to 135.9 MPa and a flexural modulus of up to 6.71 GPa, surpassing those of pure PBA-a by 28.7% and 33.1%, respectively. Moreover, the glass transition temperature ( T g ) increased by 19.56°C. Furthermore, there was a slight improvement in flexural strength compared to the heat-cured product, and no significant loss in thermal properties was observed. The method demonstrated in this study presents a novel approach for the rapid molding and preparation of benzoxazine in composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 5
·2289-2298
·
IF 6.97
Leitao Cao,Yang Si,Yuanyuan Wu,Xueqin Wang,Jianyong Yu,Bin Ding
Low-density nanofibrous aerogels enable various applications but are often hindered by their fragile bendability and poor tensile strength. Herein, we report a strategy to design nanofibrous aerogels with robust bendability and superelastic property, which has been achieved by fabricating bamboo lashing-like structures through a freeze-drying method. The obtained reinforced nanofibrous aerogels (RNFAs) can maintain their structural integrity after 100 bending-recovery cycles at a bending angle of about 100°. Particularly, the RNFAs can completely revive from large deformation with a fast recovery speed (∼834 mm s−1). Significantly, the internal hierarchical porous structures and hydrophobicity of the materials provide them with ultralight properties (density <11 mg cm−3), efficient sound absorption capability (noise reduction coefficient of 0.41) and good moisture resistance; thus, they are promising options in cabins, vehicles, and the regulation of indoor reverberation.
研究领域:
材料科学
·
声学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2021
·Vol. 13
·期 22
·3860
·
IF 4.329
Do Quang Tham,Mai Duc Huynh,Nguyen Thi Dieu Linh,Do Thi Cam Van,Do Van Cong,Nguyen Thi Kim Dung,Nguyen Thi Thu Trang,Pham Van Lam,Thai Hoang,Tran Dai Lam
In this study, vinyltrimethoxysilane-treated hydroxyapatite (vHAP) and PMMA-grafted HAP (gHAP) were successfully prepared from original HAP (oHAP). Three kinds of HAP (oHAP, vHAP and g HAP) were used as additives for the preparation of three groups of HAP-modified PMMA bone cements (oHAP-BC, vHAP-BC and gHAP-BC). The setting, bending and compression properties of the bone cements were conducted according to ISO 5833:2002. The obtained results showed that the maximum temperature while curing the HAP-modified bone cements (HAP-BCs) decreased from 64.9 to 60.8 °C and the setting time increased from 8.1 to 14.0 min, respectively, with increasing HAP loading from 0 to 15 wt.%. The vHAP-BC and gHAP-BC groups exhibited higher mechanical properties than the required values in ISO 5833. Electron microscopy images showed that the vHAP and gHAP nanoparticles were dispersed better in the polymerized PMMA matrix than the oHAP nanoparticles. FTIR analysis indicated the polar interaction between the PO4groups of the HAP nanoparticles and the ester groups of the polymerized PMMA matrix. Thermal gravimetric analysis indicated that mixtures of ZrO2/HAPs were not able to significantly improve the thermal stability of the HAP-BCs. DSC diagrams showed that the incorporation of gHAP to PMMA bone cement with loadings lower than 10 wt.% can increase Tgby about 2.4 °C.Keywords:HAP-modified bone cement;vinyltrimethoxysilane-treated HAP;PMMA-grafted HAP;bending;ISO 5833
研究领域:
生物材料学
·
骨科医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2020
·
IF 4.231
Sipei Zhao,Li Pei,Hailong Li,Xin Zhang,Weihong Hu,Guizhe Zhao,Zhi Wang
Thermoset resins have wide applications in coatings, adhesives, and structural components, but often their usage is often limited by their intrinsic brittleness . Here, we report that a thiourea based polymer blending with a kind of thermoset resin (benzoxazine) yields materials improve toughness without deteriorating other properties. Synchronous enhancement in the toughness properties, flexural properties and thermal properties (T g ) is showed in blends containing 5 wt% thiourea based polymer. Notably, there is more than 156%, 35% and 14 °C improvements in the above properties respectively compared with those of polybenzoxazine. A curing mechanism, chemical structure , phase morphology and processing properties of blends are discussed. The results illustrate the modified and newly introduced hydrogen-bonded pairs in the system are the main reason for simultaneously enhancing the properties of cured products. The method by modifying the hydrogen bonds type and amount of thermoset resin is facile to get enhanced comprehensive properties and have a profound meaning for fiber-reinforced composite.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2020
·Vol. 7
·期 10
·105001
·
IF 1.929
Lin Tang,Guoyou Gan,Xianglei Yu,Chengbin Liu,Junhua Cheng
Due to the high conductivity and stability of silver, silver ink has been widely used in the field of printed electronics. However, since mechanical strain would cause the contact between key particles to be broken. Recently, higher requirements have been put on the bending resistance of silver paste. In this experiment, by preparing Ag NPs: Ag Flakes composite materials of 20:80 and 30:70 respectively, a new method for preparing stable modified flake silver powder is proposed, and the attachment and growth methods of Ag NPs reduced on micron flake silver powder is discussed. Flake silver powder, dispersant and reducing agent are added to the silver-ammonia complex, and the nano-silver particles are reduced on the flake silver powder by controlling the reaction conditions. When Ag+: Ag Flakes in the solution is 30:70, there is a clear interface between the silver particles and the silver flakes, and the size distribution range is between 10 and 100 nm; when Ag+: Ag Flakes is 20:80, the distance between the nano-silver particles and the silver plate crystal plane is about 0.222 nm and 0.260 nm, these spacings represent the (1–12) and (004) planes of Ag, respectively. The reduced silver particles grow on the surface of the silver sheet, the size is about 5 ∼ 60 nm, and form a sheet-point combination of shaped silver powder, which can be used to make conductive silver paste with cost and performance competitiveness. The reaction can be completed at room temperature (5 ∼ 25 °C) and atmospheric pressure (80 ∼ 100 kPa), the operation is simple, the reaction time is short, and it has a positive effect on the commercial production of printable highly conductive silver paste.
研究领域:
材料科学
·
纳米技术
·
电子材料
✓ 已验证
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Shi-Wei Wang,Peng-Fei Qian,Di Zhang,Wen-Hao Geng,Yi-Song Zhang,Xuan-Chen Liu,Lu-Yao Tian,Qingxia Zhu,Hong-Zhang Geng
In this work, the large-area poly 3,4-ethylenedioxythiophene (PEDOT: PSS) transparent conductive films (TCFs) were prepared by the solution shear method. These films exhibited excellent bendability , strong adhesion , superior uniformity, and high-light transmission. The optimum photoelectric figure of merit (FoM) of the films was 195.5, and the optimum photoelectric performance at a low sheet resistance (< 50 Ω/sq) was observed in the three-layer films, which was prepared at a dilution ratio of 2:1 and a shear rate of 1 mm/s, showing a thin-layer resistance of 34.7 Ω/sq, a transmittance of 93.2 %, an FoM of 151.9 and electrical conductivity of 2398.6 S/cm. The prepared films were used as the organic light-emitting diode (OLED) anode, and the large-area flexible green OLED device with good uniformity was obtained. The maximum current efficiency of the prepared large-area flexible OLED was 2.16 cd/A, reflecting the great potential of this solution-shear film in the field of flexible devices.
研究领域:
材料科学
·
光电技术
·
柔性电子
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 6
·1389
·
IF 3.1
Xu Wang,Shao-Cong Li,Duo-Wen Xiang,Min Gao,Hong-Mei Zuo,Dian-Sen Li
Recently, short-fiber-reinforced thermoplastic composites (SFRTPCs) have been playing a more and more crucial role in the application of automotive interior materials due to their advantages of low density and environmental resistance properties. However, their relevant mechanical properties need to be optimized. Previous investigations revealed that the surface modification of fibers is useful to improve their mechanical properties. In this work, carbon fiber (CF)-reinforced polylactic acid (PLA) composites modified with MXene and graphene oxide (GO) were prepared by twin-screw extrusion and injection molding methods. Short CF was firstly modified with polyetherimide (PEI), then different weight ratios of MXene-GO (1:1) were subsequently modified on PEI-CF. Finally, the flexural properties and failure mechanisms were analyzed. The results showed that MXene-GO was successfully coated on CF surface, and the flexural strength and modulus of CF-PEI-MXene-GO-reinforced PLA (CF-PEI-MG/PLA) composite were improved compared to that of CF/PLA composite. In addition, the fracture sections of the composites were flat and white, and the fibers bonded well with PLA for CF-PEI-0.1MG/PLA composite compared to CF/PLA composite. The present study could provide a reference for further improving the mechanical performance of PLA-related composites.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2018
·Vol. 33
·期 3
·744-748
·
IF 0.524
Xu Renxin,Cheng Shixin,Zhou Jing,Shen Jie,Li Zheng,Tan Xing
A novel epoxy-imide resin based on diglycidyl ether of bisphenol-A and N-(4-hydroxyphenyl) terahydrophthalic anhydrideimide (HTAM) was synthesized. The structural characterization of the epoxy-imide resin was conducted by FT-IR spectra. 4,4’-diaminodiphneylmethane (DDM) was used as a curing agent for the epoxy-imide resin. The thermal properties of the cured resin were evaluated with dynamic mechanical analyses (DMA) and thermogravimetric analysis (TGA). The results showed that the cured resin exhibited a high glass transition temperature ( T g ) of 186 °C when the molar amount of HTAM was 0.04 mol in the resin. The yields of the cured resin at 800 °C raised from 16.45% to 19.41%. The flexural properties were also measured, the flexural strength raised from 79.4 to 95.7 MPa, and the flexural modulus exhibited from 2.6 to 3.0 GPa.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Materials Research
·
2024
·Vol. 115
·期 6
·391-399
·
IF 0.7
Haiqing Li,Yanru Wang,Runze Liu,Shuming Wang
Due to their special structure and many excellent properties, porous Si 3 N 4 ceramics have a wide range of potential applications as a new structural and functional integrated material. In the present study, porous Si 3 N 4 ceramics with excellent bending properties and satisfactory porosity were prepared by the gel-casting method. The variations in porosity, bending strength, fracture morphology and phase composition of the porous Si 3 N 4 ceramics with different weight fractions of La 2 O 3 –MgO sintering additive were investigated. The results showed that the density of porous Si 3 N 4 ceramics increased linearly with the increase of sintering additive content. When the content of sintering additive increased from 2.5 wt.% to 10 wt.%, the porosity of porous ceramics decreased from 30 % to 10 %. With the increase of sintering additive content, the bending strength of the samples first increased and then decreased. When the sintering additive content was 5.0 wt.%, the average bending strength of the samples reached a maximum of 240.88 MPa, and scanning electron microscopy and X-ray diffractometry results showed that β-Si 3 N 4 particles with well-developed pores and a maximum aspect ratio of 5.8 were formed in the porous silicon nitride ceramics. This study provides a reference for the preparation of porous Si 3 N 4 ceramics with good bending properties and porosity.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2015
·
IF 2.587
Xinyan Dai,Zhu Xiong,Songqi Ma,Chao Li,Jinggang Wang,Haining Na,Jin Zhu
Epoxidized citric acid (ECA) is synthesized as a highly reactive bio-based compatibilizer to improve the flexural property of polylactide (PLA)/microcrystalline cellulose (MCC) blends. Confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analysis, ECA includes three oxirane groups in its chemical structure with the rather high epoxy value at 0.76. After adding 1–5 wt % ECA in PLA/MCC blends, the interfacial adhesion between PLA and MCC is significantly improved. Accordingly, flexural strength, flexural modulus as well as impact strength of PLA/MCC/ECA blends are all improved and thus the increase of the flexural properties. This work suggests an effective way to create biobased compatibilizer with high reactivity and hereby displays a feasible way to fabricated fully bio-based PLA/MCC blends with high performance.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RESEARCH
·
2018
·Vol. 27
·期 1
·10-13
·
IF 1.767
Chen Jie,Dong You-Jia,Jin Fan-Long,Park Soo-Jin
In this study, epoxy-based composites were prepared using diglycidyl ether of bisphenol A (DGEBA) as the matrix, carbon fiber cloth (CFC) as the reinforcing agent, and metallic powder as the conductive filler. The mechanical and electrical properties of DGEBA/CFC and DGEBA/CFC/metallic powder composites were investigated using several techniques. The morphology of the fracture surface was investigated using field-emission scanning electron microscopy. The flexural strength of the DGEBA/CFC composites was found to significantly increase with the addition of CFC. The electrical conductivity of the DGEBA/CFC composites significantly increased with the increasing amount of CFC and further increased after the addition of metallic powders. The electrical conductivity of the DGEBA/CFC composites significantly improved with the addition of a small amount of graphene.
研究领域:
材料科学
·
复合材料工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）