JOURNAL OF APPLIED POLYMER SCIENCE
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2015
·Vol. 132
·期 45
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IF 1.768
Mengye Cao,Hualin Wang,Ruizhi Cai,Qing Ge,Suwei Jiang,Linfeng Zhai,Shaotong Jiang
This work aimed to develop a novel epoxy-modified tung oil waterborne insulation varnish with blocked hexamethylene diisocyanate as a curing agent. The Diels–Alder reaction between tung oil and maleic anhydride, and the ring-opening esterification reaction of epoxy resin were confirmed. The conversion rate of epoxy was explored as a function of reaction time and temperature. The effects of epoxy resin content on the thermal stability, water absorption and insulation properties (insulation strength, volume resistivity, and surface resistivity) of films were investigated, and the resistances of films to salted water were evaluated. The increase in epoxy resin contents could improve the thermal stability and insulation properties of films, and decreased the water adsorption of films, but when the epoxy resin content reached 30% and above, the water solubility of resin became poor. After being immersed in 3.5 wt % NaCl solution, the electrical insulation strength of films were lower than that in dry state, and decreased as the immersed time prolonged. In particular, the electrical insulation strength loss of films increased significantly for epoxy resin content at 15% and below. Furthermore, the increase of epoxy resin content could improve the hardness and adhesion of films, but the flexibility of films became worse. On the basis of experimental, the epoxy resin content at 25% was appropriate to prepare waterborne epoxy-modified tung oil resin. The resulting varnish may have potential as an immersing insulation varnish for the spindle of electric motor. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42755.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Surfaces and Interfaces
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2023
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IF 6.2
Guodong Liu,Zhongming Song,Xiuan Gao,Yinfeng Wang,Zhijian Li
Paper, a low-cost and eco-friendly substrate, can be used to prepare flexible electronic devices by resorting to surface modification technology. In this study, we investigated the surface modification of paper substrates, including those that were uncoated or coated with traditional mineral coatings , to analyze the enhancements to surface flatness and water resistance using a UV curing varnish layer. Furthermore, we explored the formation of perovskite films on the surface-modified paper substrates utilizing a PEO-doped perovskite precursor solution in ambient air, and the surface morphology , crystallinity , photoluminescence properties, and absorption properties of the prepared perovskite films were discussed accordingly. Considering the nontransparent feature of paper-based substrates, the inverted perovskite light-emitting device was finally assembled by transfer printing a transparent PEDOT:PSS layer as a top electrode. The conductive and optical properties of the electrode layer were thus analyzed as well. It is found that the surface modification of paper substrates via printing the UV curing varnish can illustrate significant improvements, such as pore-filling on the surface, a more than 10-fold reduction in roughness, and downward penetration. Moreover, prepared perovskite films on the surface-modified coated paper exhibit superior enhancements, including photoluminescence, higher crystallinity, and surface roughness and porosity. Devices fabricated on the surface-modified substrates are less susceptible to short-circuiting. The electroluminescence on the surface-modified coated paper substrate is 2.16 times higher than the prepared device on the surface-modified base paper substrate and even 3.23 times higher than on the PET substrate. Therefore, it is quite feasible to fabricate a perovskite light-emitting device on the modified surface of a paper substrate by using a printed UV curing varnish layer, which is expected to be a promising coating to polish the paper surface in the preparation of electroluminescent devices.
研究领域:
材料科学
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光电技术
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表面工程
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2019
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IF 7.65
Ning Yang,Tao Yang,Wei Wang,Huaiyin Chen,Weihua Li
In this study, the composite of two-dimensional graphene oxide (GO) nanosheets and button-shaped polyaniline (PANI) was synthesized and further modified by polydopamine (PDA). The obtained PDA-PANI-GO composite was used to enhance the corrosion protection ability of nontoxic water-based alkyd varnish (WAV). The chemical composition, functional groups and surface morphologies of GO, PANI-GO and PDA-PANI-GO composites were characterized by XRD, FT-IR XPS and SEM. The anticorrosion performance was demonstrated by electrochemical impedance spectroscopy measurements and polarization tests. Due to the physical barrier effects and surface hydrophobicity of PANI-GO composite, the approaches of the caustic substances to the surface of the metal was inhibited, while the highly adhesive PDA molecules reinforced compatibility between fillers and WAV. As results, PDA-PANI-GO composite introduced WAV enhanced corrosion prevention performance. Under the optimal conditions, where the ratio of PDA to PANI-GO was kept at 2:1, the impedance values increased by over two orders of magnitude compared with bare steel.
研究领域:
材料科学
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腐蚀与防护
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表面化学
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DOI
PubMed
高影响因子
POLYMER
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2024
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IF 4.1
Zongzheng Zuo,Guangxin Gu,Shuxue Zhou
In this study, three perfluoro alcohol with different fluoroalkyl chain length, i.e., 3,3,3-trifluoro-1-propanol (TEOH1), 2-perfluorobutyl ethanol (TEOH4), 2-perfluorohexyl ethanol (TEOH6), were first reacted with polyisocyanate to get hardeners bearing various contents and lengths of fluoroalkyl chain. The fluorinated polyisocyanate hardener was then adopted to fabricate hydrophobic two-component polyurethane (2K PU) clearcoats. The highest water contact angles (WCAs) of the hydrophobic 2K PU clearcoats with no haze and non-sticky surface are 91.9°, 101.6° and 106°, achieved at the perfluoro alcohol dosage of 10 %, 20 % and 20 % for TEOH1, TEOH4 and TEOH6, respectively. Accelerated weathering and outdoor exposure tests were adopted to examine the hydrophobicity durability of the perfluoro alcohol-modified coatings, and dirt pick-up resistance (DPUR) outdoors was also monitored. All coatings showed decreased WCAs in weathering tests. Nevertheless, WCAs of coatings with ≥20 % TEOH4 and ≥5 % TEOH6 remained hydrophobicity after 228-day outdoor exposure. Loss of hydrophobicity is attributed to the oxidation of PU matrix, removal of free perfluoro alcohol-modified polyisocyanate and embedding of silicate dirt. Improved DPUR of 2K PU clearcoat was demonstrated outdoors after incorporation of perfluoro alcohol, especially for the cases with TEOH4 and TEOH6 under an adequate dosage. As a whole, longer fluoroalkyl chain favors the acquisition of both higher hydrophobicity, better hydrophobicity durability, and better outdoor DPUR.
研究领域:
材料科学
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表面化学
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DOI
高影响因子
POLYMER
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2025
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IF 4.5
Zongzheng Zuo,Shuxue Zhou
In this study, 2-(perfluorohexyl)ethyl methacrylate, hydroxyethyl methacrylate and methyl methacrylate were used to synthesize three random fluorinated polyacrylates with various fluorine contents ( i.e. , F1H1, F3H1, and F5H1) and one block fluorinated polyacrylate ( i.e. , PFPHM) through traditional radical polymerization and atom transfer radical polymerization, respectively. These copolymers were further adopted as hydrophobic additives to incorporate into 2K polyurethane (PU) clearcoats. Effect of the type and dosage of the fluorinated polyacrylate on the haze, surface hydrophobicity, outdoor hydrophobicity durability and dirt pick-up resistance (DPUR) of modified coatings were investigated. Fluorinated polyacrylate additive with higher fluorine content is easier to cause haze of 2K PU clearcoats, nevertheless, hydrophobic surface could be acquired at lower dosage, alleviating its negative effect on transparency. PFPHM showed extremely higher hydrophobicity modification efficiency compared to the random polyacrylate additive, due to its easy enrichment at the superficial layer of 2K PU clearcoats. Moreover, PFPHM-modified 2K PU coatings presented the best hydrophobicity durability and dirt pick-up resistance in outdoor exposure test. The loss of hydrophobicity outdoors was mainly due to the aging of PU matrix, loss of fluoroalkyl chains, and partially to the dirt adhesion.
研究领域:
高分子科学
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材料工程
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表面化学
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涂料技术
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纳米技术
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产品关联
DOI
高影响因子
GREEN CHEMISTRY
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2025
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IF 9.2
Jiahui Liu,Chuying Li,Yanwei He,Bo Deng,Haitao Huang,Siwei Liu,Yi Zhang
The widespread use of polyimide varnish in semiconductors, packaging, and flexible displays has created increasing demand for efficient and environmentally friendly preparation. Compared to polyamic acid varnish, polyimide varnish offers enhanced stability and significantly improved process control, as it eliminates the need for chemical reactions during subsequent production steps. However, traditional polyimide varnish synthesis involves the preparation of polyamic acid followed by chemical imidization, a complex and time-consuming process that includes precipitation, washing, and dissolution. This method is not only costly but also poses environmental and safety risks. In this study, we propose a high-temperature one-step process to prepare a colorless polyimide varnish using the environmentally friendly solvent 3-methoxy-N,N-dimethylpropanamide (MDMPA), and benzoic acid as a catalyst. The process requires only 4 h to obtain high molecular weight polyimide varnish without aftertreatment. The varnish can be easily converted into a transparent film through low-temperature drying. Additionally, by introducing a small amount of 3,5-diaminobenzoic acid (DABA) for copolymerization, polyimide synthesis can be successfully achieved without external catalysts. The resulting polyimide exhibits a higher imidization degree and significantly improved peel strength between the polyimide and copper foil. This one-step process not only maintains the superior properties of colorless transparent polyimides (CPI) but also reduces reliance on toxic solvents, enhances production efficiency, and provides an environmentally sustainable solution for the large-scale production of high-performance polyimides.
研究领域:
材料科学
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高分子化学
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绿色化学
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化学工程
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电子材料
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可持续制造
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产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2020
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IF 4.469
Zhong Liang,Jiantao Zhu,Fuqiang Li,Zhimin Wu,Yuejin Liu,Di Xiong
In this paper, a series of self-crosslinking waterborne polyurethane (WPU) dispersions with side chain, which is (3-(2-Aminoethyl)aminopropyl)trimethoxysilane (AEAPTMS) as the diamine chain extender, were prepared. The characteristics of WPU with different dosages of AEAPTMS were evaluated, including particle size, crystallinity, surface performance, water resistance and thermal stability. It was demonstrated that AEAPTMS was successfully incorporated into the WPU from Fourier-transform infrared spectroscopy (FT-IR). Once the content of AEAPTMS increased to 5 %, the WPU dispersions became gelatinous. That is, the siloxane groups were hydrolyzed into a cross-linked structure during the emulsification process. The particle size enlarged with the increasing dosage of AEAPTMS in transmission electron microscopy (TEM). The X-ray photoelectron spectroscopy showed that the silane in the cross-linked WPU migrated freely towards the WPU film surface. The addition of AEAPTMS enhanced the tensile strength, hydrophobicity, water resistance and thermal stability of WPU film. Meanwhile, the elongation at break and crystallinity of WPU films were declined. Besides, interestingly, the glass transition temperature of WPU films followed the trend of first rising and then falling. By adding wetting agent, antifoaming agent, adhesion promoter and flatting agent into WPU, the water-based varnish was prepared. The pencil hardness, water resistance, adhesion and anti-adhesion of water-based varnish were best in the application on the stainless steel substrate when the WPU sample was Si-WPU-3.
研究领域:
高分子科学
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材料科学
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表面化学
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涂料技术
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DOI
高影响因子
Surfaces and Interfaces
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2024
·
IF 5.7
Lingyun Ye,Haohui Li,Jiawei Xiang,Junqi Chen,Xin Zhang,Shaona Zheng,Wenbo Liao
In this study, Ag@SiO 2 core-shell nanoparticles were synthesized using the Stöber method and then physically mixing with MPS functionalized poly (styrene-co-acrylate) (PSA) emulsion to obtain a novel antibacterial composite material (PSA/Ag@SiO 2 ). The dispersion of composite latexes was improved by the formation of Si-O-Si covalent bonds , and the migration of AgNPs on the surface of composite films enhanced their antimicrobial activity. Analysis of UV-Vis absorption spectra , TEM images, XPS and XRD data confirmed the core-shell structure of Ag@SiO 2 and the successful coating of AgNPs by SiO 2 . TEM micrographs showed that Ag@SiO 2 core-shell nanoparticles were uniformly dispersed in the composite latexes, with an average particle size of 198 nm for PSA/Ag@SiO 2 composite latexes, larger than that of PSA latexes (162 nm). FTIR spectra also indicated the presence of Si-O-Si covalent bonds resulting from the sol-gel reaction between MPS functionalized PSA with Ag@SiO 2 . XPS and WCA characterization revealed the disruption of the core-shell structure of Ag@SiO 2, leading to the migration of AgNPs to the air-film interface. The results of antibacterial activity demonstrated that PSA/Ag@SiO 2 composite films displayed antibacterial activity against both E. coli and S. aureus , and the former displayer a slightly better antibacterial activity than the latter. The water-based acrylic polymer coatings with antibacterial properties explored in current work have various applications in wood paints, varnishes, metal protection, decorative systems and other related fields.
研究领域:
材料科学
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纳米技术
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高分子科学
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化学工程
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生物技术
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产品关联
DOI
高影响因子