Polymers
·
2022
·Vol. 14
·期 23
·5323
·
IF 4.967
Xu Luo,Yu Li,Shuaijie Li,Xin Liu
As a typical brittle material, epoxy resin cannot meet its application requirements in specific fields by only considering a single toughening method. In this paper, the effects of carboxyl-terminated polybutylene adipate (CTPBA) and zinc powder on the mechanical properties, adhesion properties, thermodynamic properties and medium resistance of epoxy resin were studied. A silane coupling agent (KH-550) was used to modify zinc powder. It was found that KH-550 could significantly improve the mechanical properties and bonding properties of epoxy resin, and the modification effect of flake zinc powder (f-Zn) was significantly better than that of spherical zinc powder (s-Zn). When the addition amount of f-Zn was 5 phr, the tensile shear strength and peel strength of the composites reached a maximum value of 13.16 MPa and 0.124 kN/m, respectively, which were 15.95% and 55% higher than those without filler. The tensile strength and impact strength reached a maximum value of 43.09 MPa and 7.09 kJ/m2, respectively, which were 40.54% and 91.11% higher than those without filler. This study provides scientific support for the preparation of f-Zn-modified epoxy resin.Keywords:flake zinc powder;epoxy;modification;toughen
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Minerals
·
2022
·Vol. 12
·期 9
·1068
·
IF 2.818
Yangshuai Qiu,Zhenfei Mao,Kangkang Sun,Lingyan Zhang,Yupeng Qian,Tao Lei,Wenbo Liang,Yaxin An
Flotation is one of the most used methods to upgrade natural graphite resources. However, the efficiency is usually decreased due to the entrainment of undesirable fine gangue minerals. In this work, the impact of different factors such as particle size, pulp density, and flotation reagent on the entrainment of mica and quartz in a flake graphite flotation was studied. The single gangue mineral flotation results showed increased gangue entrainment when reducing the particle size of gangue minerals and increasing the pulp density. Moreover, the flotation of artificial mixtures indicated enhanced entrainment of mica and quartz in the presence of graphite particles. The collector and frother also strongly affect gangue entrainment by modifying the structure and stability of the froth. Kerosene, which has a prominent deforming feature, can reduce gangue entrainment more effectively than diesel.Keywords:entrainment;froth flotation;quartz;mica;flake graphite
研究领域:
矿物加工
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Linbo Zhang,Weihong Wan,Xianyu Jiang,Bo Wang,Liangjun Yin,Simeon Agathopoulos,Jiangliang Xie,Li Zhang,Haipeng Lu,Longjiang Deng
The popular magnetic material of flaky carbonyl iron (FCI) is unfortunately vulnerable to electrochemical corrosion when exposed to a salty and foggy environment. This work reports on a sol-gel method that successfully modifies FCI particles, using lithium silicate (Li 2 SiO 3 ), poly dimethyl siloxane (PDMS), and γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560), to synthesize Fe@SiO 2 @KH560@PDMS hybrid composite, related to its organic–inorganic hybrid coatings. The favorable hydrophobicity of organic–inorganic hybrid coatings with the static contact angle of 120° impeded the contact between corrosive medium and FCI core. The results of electrochemical experiments also confirmed its excellent corrosion resistance , since the corrosion potential E corr was positively shifted to 0.01 V, and the corrosion current I corr was three orders of magnitude lower than that of the unmodified FCI particles. Thermogravimetric (TG) analysis indicates that the presence of hybrid coatings also improved the thermal stability of the produced material towards oxidation . Furthermore, the results of molecular dynamics simulation reveal that the hybrid layer inhibits the diffusion of corrosive medium.
研究领域:
材料科学
·
电化学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·
IF 2.758
Yining Ma,Huaijuan Zhou,Jingting Zhu,Shidong Ji,Shanhu Bao,Rong Li,Ping Jin
Flake-like VO 2 (M) has been successfully synthesized by annealing plate-like (NH 4 ) 0.6 V 2 O 5 in vacuum and its thermochromicity was investigated. Preparation conditions such as temperature and vacuum degree have been varied to obtain the pure phase. The formation mechanism from ammonium vanadium bronze to VO 2 (M) has been explored. The flake-like VO 2 (M) shows an excellent thermochromicity; the infrared modulation at 2500 nm was up to 56.6% with a 30% visible transmittance which will be beneficial for smart windows, smart curtains or other applications.
研究领域:
材料科学
·
热致变色材料
·
纳米材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2023
·
IF 6.4
Zhi Lei,Shengzhi Duan,Xiaowen Wu,Chaochao Gao,Lianyi Wang,Xin Min,Zhaohui Huang,Minghao Fang,Ruiying Luo,Bingcheng Luo
Electrothermal elements are used in electronic devices, physiotherapy, and health care due to their lightweight and fast temperature response. However, the high cost and susceptibility to oxidation of traditional electrothermal materials limit their application. In this work, a low-cost, environment-friendly, controllable, and high-performance natural flake graphite-based electrothermal coating is proposed that can be used in various electrothermal applications. The results demonstrate that the morphology and electrothermal properties of the coatings can be controlled based on pressure engineering and the use of various adhesives. The uncompressed electrothermal coatings can reach a maximum temperature of 157.9 °C and a maximum electric conductivity of 27.89 S/m at 36 V, whereas the compressed coatings can reach a maximum temperature of 199 °C at only 18 V and a maximum conductivity of 433.6 S/m, which is 22 times higher than the corresponding uncompressed coatings. This work provides a low-cost, high-performance, and well-attainable industrialization path for the application of natural graphite-based electrothermal coatings in indoor heating, light electrothermal clothing, and snow and ice removal.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Ye Zhang,Dawei Liu,Ligong Zhou,Mingxing Tang,Xuekuan Li,Yongxing Yang
Alpha-alumina (α-Al 2 O 3 ) materials has a wide range of applications because of its excellent properties at high temperature. Tabular α-Al 2 O 3 was unexpectedly synthesized by etching mullite from Si x Al y O z composites since our original intention was highly porous α-Al 2 O 3 . Silica-alumina xerogels with different Al/Si molar ratio as 3, 6, 9 and ∞ (pure alumina) were prepared via sol-gel route, followed by calcination at 1400 °C to obtain Si x Al y O z composites. XRD results showed that the composite existed as mullite when the Al/Si ratio equaled to 3 and as the combination of mullite and corundum (α-alumina) when the Al/Si ratio equaled to 6 and 9, while pure α-Al 2 O 3 was obtained when Al/Si ratio equaled to ∞ signed as sol-gel α-Al 2 O 3 . The mullite phase in Si x Al y O z composites could be etched completely by hydrofluoric acid under room temperature in terms of the treating time was long enough and left tabular α-Al 2 O 3 for the samples with Al/Si molar ratio as 6 and 9. The interaction between mullite and α-Al 2 O 3 during the thermo process may direct the formation of tabular morphology. Structural and property characterizations show the tabular morphology, low surface area, perfect crystallinity and weak acidity of α-Al 2 O 3 . Furthermore, the adsorption of dibenzothiophene, a molecular with planar morphology, on tabular α-Al 2 O 3 , sol-gel α-Al 2 O 3 as well as γ-Al 2 O 3 was investigated at room temperature in comparison. Tabular α-Al 2 O 3 exhibited the highest adsorption capacity and best regeneration ability than other two.
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
INTEGRATED FERROELECTRICS
·
2019
·
IF 0.486
Xinling Hu,Dongxu Li,Yanzhen Huang
Titanium carbonitride (TiCN) show many excellent properties as new multifunctional material. In this article, nano-sized TiCN were prepared by environmentally friendly and low-cost hydrothermal processes. The composition, structure and morphology of TiCN were characterized by scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy. Hardness performance was measured by microhardness tester. Fluorescence performance was tested by fluorescence spectrometer under visible light. Based on the results, the samples prepared at 1000–1100 °C had the highest purity and hardness. The flaky TiCN compounds exhibit excellent mechanical properties and show a promising application in ultra-hard materials.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2018
·Vol. 29
·期 29
·295603
·
IF 3.404
Huanqin Zhao,Yan Cheng,Wei Liu,Zhihong Yang,Baoshan Zhang,Guangbin Ji,Youwei Du
Special electric and magnetic characteristics make Fe3O4 widely applied in the electromagnetic (EM) wave absorption region. However, for pure Fe3O4, it is still a challenge to simultaneously obtain high absorption intensity and broadband absorption at a low thickness, owing to its low dielectric property. As we realized, flake configuration and the porous structure have obviously promote the EM wave absorption property. Because the former can lead to multi-reflection between flakes and the latter is conductive to interface polarization, flaky Fe3O4 with a porous and coarse surface was designed to overcome the deficiency of traditional Fe3O4 particles. The experimental results demonstrate that the flaky configuration is conductive to enhancing the dielectric coefficient and optimizing impedance matching. Moreover, the complex permittivity rises with the aspect ratio of the sheet. Under a suitable dimension, the flaky Fe3O4 could acquire targeted EM wave absorption capacity in the X band (8–12 GHz). In detail, the maximum reflection loss (RL) could reach a strong intensity of −49 dB at 2.05 mm. The effective absorption bandwidth (EAB) with RL below −10 dB is 4.32 (7.52–11.84) GHz, which is almost equivalent to the whole X band (8–12 GHz). Even more exciting, when regulating the thickness between 2.05 and 3.05 mm, the EAB could cover the entire C and X bands (4–12 GHz). This study provides a good reference for the future development of other ferromagnetic materials toward specific microwave bands.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2023
·
IF 4.6
Enbo Li,Yu Bai,Peng Zhang,Hongxia Liu,Wen Ma,Yingwei Qi,Te Wang,Ziqian Zhang,Sinan Gao
Electronic structure adjustment on materials' surfaces often leads to materials obtaining novel performances. Flake Al powder is a classical low infrared emissivity material at room temperature. However, this powder shows intense infrared radiation over 500 °C due to its high-temperature oxidation , which restricts flake Al powder's application as low infrared radiation material in higher temperatures. For this reason, the Al@ZrO 2 composite was prepared by a solvothermal method to improve its thermostability. This composite can be used as low infrared radiation material over 500 °C for the long term, even at 700 °C for a short time. According to the experimental and theoretical investigation, a delocalization bond of Al–O–Zr is formed in the interface between the Al surface and ZrO 2 so that the Al surface's electronic structure is adjusted. This change of electronic structure weakens the electroaffinity of Al atoms to bond with the electron-rich groups, and the oxidation reaction of Al needs to proceed in a higher-temperature range. In this case, flake Al powder coating with ZrO 2 holds its metal properties with low infrared emissivity over 500 °C. The Al@ZrO 2 composite could be used in a higher temperature range as a low infrared radiation material.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2024
·
IF 2.5
Liang Ni,Wang Haiyan,Wang Yujia,Kang Lei,Bai Yingzhi,Sun Na
A strategy was devised for the synthesis of SAPO-34, which involved a concentrated gel system-assisted two-step crystallization method. This strategy effectively controlled the size and morphology of SAPO-34. The successful synthesis of SAPO-34 crystals with micron-scale cubic morphology and nano-scale sheets were achieved using triethylamine as a low-cost template. The paper thoroughly examined the growth evolution that occurs during the crystallization process, and it delved into the factors such as gel concentration and crystallization conditions in the synthesis. Furthermore, potential theories regarding nucleation and growth mechanisms were suggested. A systematic study was conducted to examine how the morphology and acidity of SAPO-34 zeolites impact their catalytic performance. The results confirmed that the SAPO-34 with low silicon content and lamellar structure was successfully synthesized through a two-step crystallization within a gel system of H 2 O/Al 2 O 3 = 30, with a thickness of approximately 50–300 nm. SAPO-34 nanosheets demonstrated a substantial enhancement in catalytic performance, with a catalytic life of 370 min and an 84.1% selectivity towards light olefins.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2024
·Vol. 149
·期 22
·13397-13406
·
IF 3
Huang An-Chi,Ma Xin-Yue,Cao Fang-Chao,Guo Gan-Syue,Huang Chung-Fu,Shu Chi-Min
This study examined the fire suppression properties of flake black lead (FBL) and its improved version, FBL-ZB, which includes zinc borate (ZB). We created FBL-ZB by combining 68.0 mass% FBL with 17.0 mass% ZB. This combination underwent a rigorous preparation process that included stirring, filtration, and drying. The comparative analysis conducted in this study primarily examined critical parameters, including extinguishing temperature, duration, and following cooling rate. The results clearly showed that FBL-ZB is more effective than FBL in all the parameters that were assessed. FBL-ZB effectively decreased fire temperatures to 446.8 °C in under 20 s and demonstrated a cooling rate of 1.0 °C s –1 for a duration of 120 s after extinguishing the fire. On the other hand, FBL took 30 s to put out fires, using 10.5 g of material, with a temperature of 470.1 °C before extinguishing and a cooling rate of 0.8 °C s –1 after extinguishing. The study highlighted the improved fire suppression capabilities of FBL-ZB and also added to the continuous advancement of more efficient fire suppression materials.
研究领域:
材料科学
·
消防工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 10
·1-12
·
IF 2.8
Xue Tiange,Huang Zeya,Zhang Xiaotian,Meng Meng,Yu Shixiang,Chen Tian,Fu Renli
In this paper, the effects of the composition and sintering process of the conductive silver paste on the packaging and electrical interconnection performance of the silicon carbide high temperature pressure sensor are studied in detail. At the same time, a self-built high temperature reliability test platform is used to test the electrical interconnection reliability of the conductive silver paste under high temperature environments. The results show that flake silver powder can not only effectively promote the density of the conductive silver paste, but also improve the grain boundary migration behavior of the conductive silver paste, thereby improving the electromigration resistance of the sintered silver. The prepared conductive silver paste has good compatibility with high temperature pressure sensor materials such as SiC, AlN, and Pt, and the adhesion strength reach 23.12 MPa, 26.35 MPa, and 19.22 MPa, respectively. When the silver paste does not contain flake silver, the sheet resistance of the sintered silver paste is the lowest at 650 °C, which is only 2.58 mΩ/□, and there is still room for improvement. The high temperature stability test shows acceptable performance, but in the high current test with a current density of 125 A/mm 2 , the failure time is only 105 min. After adding 20 wt% of flake silver powder, the sheet resistance of the silver paste can be further reduced to 1.50 mΩ/□ by 41.9%, and the failure time can be extended to 158 min, with a 50.5% increase.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）