NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 7
·2930-2940
·
IF 3.288
Jun Zhu,Jie Li,Chao Sang,Yunjun Luo
Waterborne polyurethane (WPU) based polymeric dyes with anthraquinone chromophores were developed to realize coloring textiles and improve color fastness. The preparation of polymeric dyes through the reaction of 1,4-diamino-2,3-diphenoxyanthraquinone (DV26) and NCO-terminated prepolymer was monitored via UV absorption spectroscopy. With the progress of the reaction, the intensity of the absorption peak of the primary amine group at 586 nm decreased as a function of reaction time. Thus, the conversion of DV26 at different times and the reaction end point could be determined. The reaction mechanism corresponded to an autocatalytic reaction equation, basically. In addition, the results of performance tests showed that the polymeric dyes exhibited good emulsion stability, ultra-low migration percentages, good water resistance and excellent thermal stability. Moreover, the application properties of DWPU on coated polyester fabrics were satisfactory.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 11
·8581-8590
·
IF 3.442
Huang Xie-Jun,Zeng Xiao-Fei,Wang Jie-Xin,Zhang Liang-Liang,Chen Jian-Feng
Transparent ZnO/polymer nanocomposites with good UV shielding performance have shown great potential applications. Due to the photocatalytic activity of ZnO, core–shell structure nanoparticles (NPs) have been used to fabricate the transparent polymer-based nanocomposites. However, it is still a challenge to synthesize core–shell structure NPs with small particle size and good dispersity, and difficult to maintain the transparency of the nanocomposites because of Rayleigh scattering caused by the big size or the aggregation of NPs. This article reports a novel reverse microemulsion combined with surface modification method for the synthesis of monodispersed silica-coated ZnO (ZnO@SiO 2 ) NPs, which are introduced into ethocel (EC) matrix to fabricate the transparent nanocomposites by the solution-mixing method. The ZnO@SiO 2 NPs with an average size of 12 nm have an obvious core–shell structure and show excellent monodispersity in toluene. The as-prepared EC/ZnO@SiO 2 nanocomposites shield all the UV light completely under 350 nm and maintain the transparency of pure EC even the solid content reaches 60 parts per hundred of EC resin by weight (phr). Importantly, the photocatalytic activity of ZnO NPs is eliminated thoroughly by the silica shell, which apparently improves the UV aging resistance of polymer (EC), enabling the applications of ZnO as durable and environmental friendly UV blocker in transparent plastics and coatings to extend the lifetime of the products.
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高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2021
·Vol. 147
·期 7
·4597-4610
·
IF 4.626
Dou Yanli,Li Xuefei,Zheng Kaiyue,Liu Jiawen,Hou Jiazi
A UV-curing flame-retardant coating with varying mass content of bisphenol A epoxy acrylate (BAEA), 2-hydroxyethyl methacrylic acid phosphate (PM-2) and polyurethane acrylate (PUA) were prepared, improving the flame-retardant and mechanical properties of jute/polypropylene (PP) composites. BAEA is the main film-forming prepolymer. Phosphate ester groups in PM-2 can promote the formation of carbon layer during combustion, and PM-2 can also be used as a good adhesion binder to improve the coating adhesion levels. The flexible long chain in PUA could reduce the shrinkage of the coating and provide further adhesion. To avoid the oxygen inhibition of the radical polymerization, isopropylthioxanthone and triethanolamine were used to reduce the reaction between photoinitiator phenyl bis (2,4,6-trimethylbenzoyl) phosphine oxide and oxygen. Compared to the uncoated composites (J–P), the peaks of heat release rate and total smoke production of coated composites decreased and limiting oxygen index values increased significantly, which revealed that the coatings showed effective fire protection effect. The bending strength of the coated composites can increase by 90% over uncoated sample J–P. This simple, low-cost and environmentally friendly UV-curing coating has good adhesion and can effectively improve the flame-retardant and mechanical properties of composites, which expand application of the flame-retardant fiber composites.
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高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 14
·3590-3597
·
IF 7.779
Qiang Wang,Wen Song,Yang Lan,Liling Cao,Ling Huang,Daojiang Gao,Jian Bi,Guohong Zou
KBe2BO3F2 (KBBF) with a perfect honeycomb hexagonal layered structure is the sole practical deep-ultraviolet (DUV) nonlinear optical material which could generate DUV coherent light through direct frequency doubling. However, the layered growth habit and the toxicity of Be severely hinder its extensive applications. Herein, a non-centrosymmetric fluoride carbonate, KLi2CO3F, was successfully developed via chemical co-substitution with KBBF as the prototype. KLi2CO3F preserves the structural merits of KBBF, containing neatly arranged infinite planar [Li2CO3F2]∞ layers. In particular, compared with the weak interlayer K–F electrostatic attraction in KBBF, KLi2CO3F presents a stronger interlayer binding energy induced by the shorter and stronger Li–F bonds, which effectively overcomes the layered tendency of crystal growth. Simultaneously, KLi2CO3F exhibits a large birefringence of approximately 0.102@546 nm and a short ultraviolet absorption edge down to 190 nm, indicating that it is a promising DUV birefringent material.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 31
·50760
·
IF 3.125
Xiaochen Yu,Jia Zheng,Zhaoxi Zhou,Qihui Chen,Maochun Hong,Heqing Fu
Firstly, cerium dioxide(CeO 2 ) was modified by 3-(Methylacryloxyl)propyltrimethoxy silane (KH-570), and modified CeO 2 (mCeO 2 ) was prepared. Then poly (urethane-acrylate) was modified by mCeO 2 , and poly (urethane-acrylate)/modified CeO 2 (PUA/mCeO 2 ) composites with ultraviolet absorption property were prepared. The morphology, thermal hydrophobicity, mechanical properties, optical properties, and UV-absorption properties of PUA/mCeO 2 composites were studied. XRD and SEM analysis showed that the modified CeO 2 had better dispersion in the matrix than that of pure CeO 2 . Ultraviolet–visible spectrum and thermogravimetric analysis were used to characterize the optical properties and thermal stability of PUA/mCeO 2 composites. The results showed that with the increasing of the mCeO 2 content, the UV-absorption property of PUA/mCeO 2 composites was improved gradually. When the content of mCeO 2 is 3%, the absorption of ultraviolet of PUA/mCeO2 composites is about 5 times of pure PUA film, and the absorption band is mainly in the UVA section. The thermal stability of PUA/mCeO 2 composites was improved with the adding of mCeO 2 . With the increasing of mCeO 2 content, the contact angle of PUA/mCeO 2 composites increased significantly. And the UV-absorption mechanism of PUA/mCeO 2 Composites was studied. UV-curable PUA/mCeO 2 composites have good UV absorption property and water resistance. They will be used in the sun screen and protect people's skin.
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高影响因子
POLYMER
·
2022
·
IF 4.432
Jie Liu,Pengcheng Miao,Wenwen Zhang,Guanjun Song,Jiale Feng,Xuefei Leng,Yang Li
Interpenetrating polymer networks (IPNs) are a non-bonded combination of two or more cross-linked polymers and have superior mechanical properties. Herein we synthesized a series of IPNs by a sequential UV-thermal dual-curing method, which is consisted of UV curable resin network and polyurethanes (PU) network. Blocked isocyanate (BI), polyols , and UV curable resin solutions were mixing completely, the resulting mixture was exposed to UV light to obtain a single network. Then the double network was formed via thermally triggered reaction of deblocking-isocyanate and polyols . The effect of polyol hydroxyl number (from two to six) on properties of IPNs was systematically studied. The results exhibit that pentaerythritol as polyol can be dual-cured by UV and heating to give the highest tensile strength (17.5 MPa), of a 21% increase compared to unheated sample. Furthermore, a series of semi-interpenetrating networks (semi-IPNs) were obtained by using polytetramethylene ether glycol (PTMEG) instead of the polyols. The results showed that introducing interpenetrating or semi-interpenetrating networks exhibit improved mechanical properties of the UV curable resin. Besides, the deblocking temperature of BI is just appropriate for the 3D-printing temperature.
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高影响因子
APPLIED CLAY SCIENCE
·
2019
·
IF 3.89
Dajian Huang,Yuting Zheng,Qiling Quan
Palygorskite , a natural 1D nanofibre, has been employed as an effective reinforce filler of natural hydrophilic polymer-based nanocomposites because of its high mechanical strength, large specific surface area and high aspect ratio . However, the hydrophilic hydroxyl groups only exist at the edge of the silicate layer of palygorskite nanofibres and in small amounts. Therefore, the reinforcement efficiency for the hydrophilic polymer of palygorskite is limited. To overcome this shortcoming, we constructed a highly hydrophilic polydopamine with catechol groups on the palygorskite nanofibre surface by a facile biomimetic method. Hydrophilic polymer carboxymethyl cellulose nanocomposites incorporated with polydopamine-coated palygorskite were fabricated by solution casting . Results show that the interfacial polydopamine layers not only facilitate the dispersion of palygorskite nanofibres in the carboxymethyl cellulose matrix but also enhance the stress transfer from the carboxymethyl cellulose matrix to the filler, improving the tensile strength and water resistance of the nanocomposites. However, several palygorskite crystals aggregate to form small bundles for the palygorskite with a high mass ratio of dopamine/palygorskite during the modification process. This phenomenon decreases the contact areas between the filler and the carboxymethyl cellulose matrix, thereby decreasing the properties of the nanocomposites. In addition, UV–vis transmittance spectra show that the nanocomposite films reinforced with polydopamine-modified palygorskite can block ultraviolet light below 300 nm, thereby retaining its relatively high transparency in the visible spectrum.
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高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Qingyong Tian,Weijing Yao,Wei Wu,Jun Liu,Zhaohui Wu,Li Liu,Zhigao Dai,Changzhong Jiang
Efficiently reclaiming the utilization of solar light in a photocatalysis system remains very challenging. By integrating full advantage of upconversion material, plasmonic metals, and narrow bandgap semiconductors, β-NaYF4:18%Yb3+ and 2%Tm3+@SnO2@Ag nanoparticles (denoted as NaYF4@SnO2@Ag NPs) are designed and successfully synthesized as a wide-spectral (UV–vis-NIR) responsive upconversion and plasmonic-enhanced photocatalyst. The as-obtained NaYF4@SnO2@Ag NPs present broadband optical absorption dimension, excellent photocatalytic efficiency, and good stability for the degradation of organic dyes. The enhanced photocatalytic performance of NaYF4@SnO2@Ag NPs can be attributed to the synergistic effects of the components composed in this core/shell architecture that result in higher photocarriers yield and favor the efficient transfer of photocarriers and energy. This work gives insight to guidance of fabricating efficient, multicomponent upconversion catalysts and proposes a potential in the field of high-efficiency environmental and energy-related applications.
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高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Huaqing Liu,Wei Liu,Dechao Hu,Wenshi Ma,Bangjun Deng
Zinc oxide@polydopamine (ZnO@PDA) core-shell nanoparticles (NPs) were prepared by depositing PDA on the surface of ZnO NPs via the self-polymerization of dopamine (DA) in alkaline solution. It was found that ZnO@PDA exhibits lower photocatalytic activity and higher UV absorbance than pure ZnO. Moreover, ZnO@PDA NPs could be homogenously dispersed in poly(vinyl alcohol) (PVA) matrix and form strong hydrogen bonding interaction with PVA molecular chains . As a result, the prepared PVA/ZnO@PDA composite films display excellent UV-shielding, mechanical and anti-UV aging properties. Particularly, the PVA composite film added with 2.0 wt% ZnO@PDA is able to shield 96.1% UV irradiation (200–400 nm) and exhibits superior tensile strength (66.3 Mpa) than pure PVA film. Moreover, the result of UV aging tests indicate that ZnO@PDA also give a positive effect on the UV stability of PVA matrix, while PVA/ZnO composite film shows serious degradation. This work proposed a facile and rational strategy to design the ZnO-based UV-shielding agent with reduced photocatalytic activity and enhanced UV absorbance, which may provide an inspiration to construct high performance UV-shielding composites.
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高影响因子
LUMINESCENCE
·
2019
·Vol. 35
·期 1
·138-143
·
IF 1.691
Xiaoshuang Li,Lite Zhao
Energy storage phosphors with millisecond period afterglow that compensate for the diming time of alternating current light-emitting diodes (AC-LEDs) have promising application. To obtain a persistent luminescence (PersL) white colour in AC-LEDs, we focussed on a red afterglow with short period phosphorescence. Ca 4 Ti 3 O 10 forms a type of perovskite-related Ruddlesden–Popper phase structure. Doping Pr 3+ ions into Ca 4 Ti 3 O 10 , an ideal red PersL was obtained. X-ray diffraction and element analysis demonstrated that our target samples were crystallized well. Steady-state and afterglow luminescence properties were investigated in detail. Notably, the PersL intensity was dependent on various excitation wavelengths. By measuring three-dimensional thermoluminescence spectra, we found that the trap depths showed a continuous distribution and that the shallowest trap contributed to the millisecond afterglow. Two PersL mechanism models were used to elucidate the electron charging and de-trapping processes under UV or blue light activation.
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高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Huiwang Dai,Shuying Xu,Jianxin Chen,Xiaozeng Miao,Jianxi Zhu
Oxalate enhanced mechanism of Fe 3 O 4 @γ-Fe 2 O 3 was developed to provide novel insight into catalytic process regulation of iron oxide catalysts in heterogeneous UV-Fenton system. And the iron oxide composite of Fe 3 O 4 @γ-Fe 2 O 3 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier transform infrared (FTIR) spectroscopy and nitrogen adsorption-desorption isotherms. The results showed that large amount of iron could be leached from catalyst in the presence of oxalate, which promoted the homogeneous UV-Fenton reactions in solution. Orange II degradation could be significantly enhanced with the increase of the ratio of homogeneous UV-Fenton process to heterogeneous UV-Fenton process. The optimum concentration of oxalate determined by experiment was 0.5 mM in oxalate enhanced heterogeneous UV-Fenton system. On this condition, the pseudo-first-order rate constant value of Orange II degradation was 0.314 min −1 , which was 2.3 times as high as that in heterogeneous UV-Fenton system. The removal rates of color and TOC were 100% and 86.6% after 20 min and 120 min treatment, respectively. In addition, the iron ions in solution could be almost completely adsorbed back to the catalyst surface in later degradation stages of Orange II. During the recycle experiments, the results showed that the increase of pH in solution and the sorption of intermediates on the catalyst surface would hinder oxalate enhanced process and lead to a decrease of degradation rate of Orange II in oxalate enhanced heterogeneous UV-Fenton system.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Yu Zhang,Xuejie Zhang,Haoran Zhang,Zhan-Chao Wu,Yingliang Liu,Li Ma,Xiaojun Wang,Wei-Ren Liu,Bingfu Lei
A series green emission phosphors Sr 3 Lu 2 (BO 3 ) 4 :Ce 3+ ,Tb 3+ (denoted as SLBO:Ce 3+ ,Tb 3+ ) with broad absorption band matching well with UV LED chip were synthesized by the solid–state reaction method. The phase and structure were analyzed with XRD , EDX , FT-IR measurements. The energy transfer between Ce 3+ and Tb 3+ in SLBO was proved by spectra and decay curves detailedly. The emission colors vary from blue to green by adjusting the ratio of Ce 3+ /Tb 3+ doped concentration. With temperature increasing, SLBO:Ce 3+ ,Tb 3+ phosphor shows well thermal stability that emission intensity retains 70% of its initial at 25 °C even temperature rising to 150 °C. The internal and external quantum efficiency of SLBO:3%Ce 3+ ,8%Tb 3+ are 77.5% and 34.8% under 340 nm excitation, respectively. Combining the as-synthesized SLBO:Ce 3+ ,Tb 3+ and red emission phosphor CaAlSiN 3 :Eu 2+ coated on a 365 nm UV chip, a warm white LEDs device with CRI of 83 was achieved. All the results indicate that the SLBO:Ce 3+ ,Tb 3+ phosphor has potential application in UV pumped white LEDs.
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高影响因子