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Particuology 2022年第8期20卷 68-78页

作者： Xiaoqian Ma Shen Yan Shengyu Zhang Quanyi Yin Xiaodong Chen Winston Duo Wu Engineering Research Centre of Advanced Powder Technology(ERCAPT)School of Chemical and Environmental Engineering College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

This work is aimed to study the effects of component size and solubility on the surface composition of spray dried(SD)uniform two-component particles fabricated by micro-fluidic spray *** precursor liquid consisting of small molecular of methionine(Met,33 g/L)or lysine(Lys,739 g/L)and large-sized silica(12 nm)were prepared by adjusting the mass ratio of components.X-ray energy disper-sive results showed that the respective enrichment degree(De)of Met and Lys on the surface of SD-M1S9 and-L1S9 prepared at 150 C were 182±9% and 125±14%.The De of hydrophobic Met for SD-M1S1 and-M9S1 were 46±9% and 4±2%,respectively,whereas relative hydrophilic Lys mainly distributed internal of the particle meanwhile the De of silica on the surface for SD-L1S1 and-L9S1 were 17±4%and 12±1%,*** temperature(120 and 180℃)showed more apparent effect on the De of amino acid for the particles of less amino *** possible formation mechanism of surface composition and the surface composition impact on the wettability of particles were *** results provide new guidance for manufacturing functional SD powders with various components.

关键词： Spray drying Uniform microparticles Two-component surface composition Size Solubility

CONTROLLING THE surface composition OF PCBM IN P3HT/PCBM BLEND FILMS BY USING MIXED SOLVENTS WITH DIFFERENT EVAPORATION RATES

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Chinese Journal of Polymer Science 2013年第7期31卷 1029-1037页

作者： Yue Sun Jian-gang Liu Yan Ding 韩艳春 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

The surface composition of poly（3-hexylthiophene-2,5-diyl） and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester （P3HT/PCBM） blend films could be changed by controlling the film formation process via using mixed solvents with different evaporation rates. The second solvent, with a higher boiling point than that of the first solvent and much better solubility for PCBM than P3HT, is chosen to mix with the first solvent with a lower boiling point and good solubility for both PCBM and P3HT. The slow evaporation rate of the second solvent provides enough time for PCBM to diffuse upwards during the solvent evaporation. Thus, the weight ratio of PCBM and P3HT （mpcBM/mp3HT） at surface of the blend films was varied from ca. 0.1 to ca. 0.72, i.e., it increases about seven times by changing from single solvent to mixed solvents. Meanwhile, the mixed solvents were in favor to form P3HT naonofiber network and enhance phase separation of P3HT/PCBM blend films. As a result, the power conversion efficiency of the device from mixed solvents with slow evaporation process was about 1.5 times of the one from single solvents.

关键词： P3HT PCBM surface composition Mixed solvents Slow evaporation.

The effect of the support on the surface composition of PtCu alloy nanocatalysts: In situ XPS and HS-LEIS studies

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Chinese Journal of Catalysis 2017年第7期38卷 1229-1236页

作者：黄俊杰宋艳英马冬冬郑燕萍陈明树万惠霖厦门大学化学化工学院固体表面物理化学国家重点实验室醇醚酯化工清洁生产国家工程实验室福建厦门361005

Supported PtCu alloys have been broadly applied in heterogeneous catalysis and electrocatalysis owing to their excellent catalytic performance and high CO tolerance. It is important to analyze the outermost surface composition of the supported alloy nanoparticles to understand the nature of the catalytically active sites. In this paper, homogeneous face-centered cubic PtCu nanoparticles with a narrow particle size distribution were successfully fabricated and dispersed on a high-surface-area Ti〇2 powder support. The samples were oxidized and reduced in situ and then introduced into the ultrahigh vacuum chamber to measure the topmost surface composition by high-sensitivity low-energy ion scattering spectroscopy, and to determine the oxidation states of the elements by X-ray photoelectron spectroscopy. The surface composition and morphology, elemental distribu-tion, and oxidation states of the components were found to be significantly affected by the support and treatment conditions. The PtCu is de-alloyed upon oxidation with CuO wetting on the TiO2 sur-face and re-alloyed upon reduction. Phase diagrams of the surface composition and the bulk com-position were plotted and compared for the supported and unsupported materials.

关键词： PtCu alloy Bimetal catalyst surface composition Phase diagram In situ XPS-LEIS

MODIFICATION OF EPOXY RESIN WITH POLYSILOXANE BEARING PENDANT QUATERNARY AMMONIUM GROUPS

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Chinese Journal of Polymer Science 2002年第6期20卷 537-541页

作者： Zuo-xin Huang Ying Huang Yun-zhao Yu The State Key Laboratory of Engineering Plastics, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Chinese Acad Sci Inst Chem State Key Lab Engn Plast Beijing 100080 Peoples R China

Polysiloxane bearing pendant quaternary ammonium groups (PSI) was used to modify the surface properties of epoxy resins. In the cured resin, PSI formed the dispersed phase. Remarkable enrichment and gradient distribution of polysiloxane on the surface region of the epoxy resins were demonstrated by XPS analysis. The composition and properties of the surface of PSI-modified epoxy resin, which is in contact with the mold, are dependent on the material of the mold. Through the incorporation. of PSI, epoxy resins with low surface energy and low friction coefficient were obtained. Polysiloxane with lower ionic group content shows a higher degree of enrichment on the resin surface and leads to a higher contact angle against water, while the polysiloxane having optimum compatibility with the epoxy resin shows a greater effect in reducing the static friction coefficient of the resin against glass.

关键词： polysiloxane epoxy resin surface composition friction coefficient

Synthesis and characterization of fluorinated polyurethane with fluorine-containing pendent groups

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Chinese Chemical Letters 2008年第11期19卷 1293-1296页

作者： Zhen Ge Xing Yuan Zhang Jia Bing Dai Wei Hu Li Yun Jun Luo School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

A novel fluorinated polyurethane （FPU） with fluorine-containing pendent groups was prepared by using fluorinated polyether glycol （PTMG-g-HFP） as a soft segment, 1,6-hexamethylene diisocyanate （HDI） or toluene diisocyanate （TD1） as a hard segment and 1,4-butanodiol （BDO） as a chain extender. FTIR, ^1H NMR, ^13C NMR and GPC were used to characterize the structure of the fluorinated polyurethane. Thermal stabilities of the fluorinated polyurethane and the corresponding hydrogenated polyurethane were studied by TGA. XPS analysis at two different sampling depths for the fluorinated polyurethane was used to investigate the surface compositions of FPU. The results showed the fluorine enrichment on the surface of FPU.

关键词： Fluorinated polyurethane Fluorinated polyether glycol surface composition

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氟硅丙烯酸酯嵌段共聚物防覆冰性能研究

氟硅丙烯酸酯嵌段共聚物防覆冰性能研究