Table of Content

10 December 2013, Volume 34 Issue 12

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Cover and Content of Chemical Journal of Chinese Universities Vol.34 No.12(2013)

2013, 34(12):  0-0. 

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Volume Contents of Chemical Journal of Chinese Universities to Vol.34(2013)

2013, 34(12):  1-1. 

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Article: Inorganic Chemistry

Calcium Carbonate Crystals with Different Morphologies Nucleated on the Self-assembled Monolayer

LIU Qing, WANG Hai-Shui

2013, 34(12):  2681-2685.  doi:10.7503/cjcu20130628

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One crystalline phase can exhibit different morphologies and growth orientations. Unit cell is the basic unit for the construction of crystals and the growth directions of the crystals are related to the macroscopic morphologies and properties of the crystals significantly. By combining the crystallography theory, experimental results and software simulation, we discussed the mechanism for the formation of different morphologies of calcium carbonate crystals nucleated on the self-assembled monolayer of L-cysteine. SEM images and XRD data demonstrated that the calcites from the(001) crystallographic plane are dominated. The structural match between the organic surface[the (√3×√3)R30° structure] and that of the(001) crystal plane of calcite may account for the nucleation from these two planes.



Molten Salt Synthesis of KMnF₃ and Luminescent Property of KMnF₃：Eu

MA Bing, WANG Wei, MENG Yu-Jia, WANG Xiao-Feng, LI Ben-Xian, LIU Xiao-Yang

2013, 34(12):  2686-2690.  doi:10.7503/cjcu20130645

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KMnF₃ and europium-doped KMnF₃(KMnF₃：Eu) were prepared via a simple molten salt synthesis(MSS) method and the samples were characterized by X-ray diffraction and photoluminescence spectra. Fluorescence spectrum analysis indicates that three luminescence centers(Mn²⁺, Eu²⁺ and Eu³⁺) coexist in KMnF₃：Eu system. By changing the molar fraction of Eu, the luminous intensities of Mn²⁺, Eu²⁺ and Eu³⁺ were further discussed.



Diverse Structures of Two Zn(Ⅱ) Coordination Polymers with 5-Amino-tetrazolate and 1,4-Benzenedicarboxylate Tuned by Solvent System

LU Wen-Guan, LIU Hong-Wen, YIN Xu-Guang, LAN Lu-Mei, LIU Hai-Yao

2013, 34(12):  2691-2698.  doi:10.7503/cjcu20130716

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The hydrothermal reaction of 5-amino-tetrazole(HATz) and 1,4-benzenedicarboxylic acid(H₂BDC) with Zn(NO₃)₂ gave a new coordination polymer {[Zn₂(ATz)₂(BDC)(H₂O)₂] ·H₂O}_n(1), and when this reaction was carried out under N,N'-dimethylformamide(DMF) solvothermal condition, another new coordination polymer {[Zn₂(ATz)₂(BDC)(DMF)₂] }_n(2) was obtained. Complexes 1 and 2 were characterized by elemental analyses, infrared spectroscopy, single-crystal X-ray diffraction, and powder X-ray diffraction. Complex 1 exhibits a 2D 3-connected(6,3) honeycomb(hcb) network with the Zn(Ⅱ) ions as 3-connected nodes, and the μ₂-ATz^- and μ₂-BDC^2- ligands as linkers, and then strong hydrogen bonding interactions extend the 2D layers into 3D supramolecular framework. While, complex 2 possesses a 3D 6-connected primitive cubic(pcu) metal-organic framework with the binuclear Zn(Ⅱ) units [Zn₂(CO)₂] as 6-connected nodes, and the μ₂-ATz^- and μ₄-BDC^2- ligands as linkers. Furthermore, their thermal stabilities and photoluminescence at room temperature in solid state were also investigated.



Analytical Chemistry

Separation and Detection of Neurotransmitter-related Substances in Urine Sample by Capillary Electrophoresis

YANG Jiao-Mei, REN Jie, LIU Hui-Qing, WANG Yong-Le, XU Zhong-Qi

2013, 34(12):  2699-2703.  doi:10.7503/cjcu20130835

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Capillary electrophoresis(CE) method was developed to separate the mixture of monoamine neurotransmitters(serotonin, dopamine, epinephrine), neurotransmitter metabolites(homovanillic acid, 5-hydroxyl indole acetic acid, vanilmandelic acid) and neurotransmitter precursors(arginine, tyrosine). The compositions, pH and concentration of background electrolyte(BGE) were optimized to separate the standard samples, meanwhile, the possible interferences by matrix components in urine as creatinine, uric acid and acetoacetic acid were investigated. Good quantitative linearity was obtained at the BGE of Na₂B₄O₇-NaOH(pH=9.90) and ultraviolet(UV) detection(200 nm) for eight neurotransmitter-related substances, which owned the limit of detection(LOD) in a range of 0.04—7.00 μmol/L. Relative standard deviation(RSD)(n=5) of migration time and peak area were 0.09%—0.48% and 0.47%—3.34%, respectively. Eventually, the developed CE method was applied for the qualitative and quantitative analysis of arginine(Arg) and vanilmandelic acid(VMA) in urine sample. Their concentrations were respectively at (95.8±3.8) μmol/L and (44.6±3.5) μmol/L with the recovery at a range of 96.65%—104.5%.



Novel Method for Identification of Protein Arginine-ADP-ribosylation Based on Chemical Derivatization and CID Fragmentation

ZHAO Zhi-Qiang, QIU Hui-Hua, YAO Jun, CHEN Yong-Feng

2013, 34(12):  2704-2709.  doi:10.7503/cjcu20130824

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High performance liquid chromatography coupled to electrospray ionization mass spectrometry(MS) was widely used to map protein posttranslational modifications in complex biological samples. But frequently-used collision induced dissociation(CID) was unsuccessful in fragmentizing arginine adenosine diphosphate(ADP)-ribosylated peptides because the spectra from CID fragmentation were dominated by ADP-ribose fragment ions at the expense of the fragments generated from peptide backbone, making the assignment of the peptide sequence very difficult. In this work, a novel method was developed for identification of arginine ADP-ribosylated peptides based on CID fragmentation. Arginine ADP-ribosylated angiotensin-Ⅰ was either converted to ornithinylated angiotensin-Ⅰ under alkaline condition or hydrolyzed to arginine ribosylated angiotensin-Ⅰ by treatment with phosphodiesterase and alkaline phosphatase. The two derivatives were then subjected to CID fragmentation during tandem MS analysis. Compared with unmodified ADP-ribosylated angiotensin-Ⅰ, the two derivatives generated more sequence specific ions in the spectra, giving enough information to localize the site of arginine ADP-ribosylation.



Simultaneous Determination of Multi-veterinary Drug Residues in Honey by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry and Multiwalled Carbon Nanotubes Cleaning

CAO Hui, CHEN Xiao-Zhen, ZHU Yan, LI Zu-Guang

2013, 34(12):  2710-2715.  doi:10.7503/cjcu20130764

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A method for determining multi-veterinary drug residues in honey by ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) and multiwalled carbon nanotubes cleaning was established. This method enabled the comprehensive screening for 52 drugs including sulfonamides, quinolones, nitroimidazoles and tetracyclines. The samples were diluted by Na₂EDTA-Mcllvaine solution(pH=4), the clean-up and proconcentration of the analytes were carried out by solid phase extraction cartridge packed with multi-walled carbon nanotubes(MWCNTs). The target analytes were separated by Waters C₁₈ column with gradient elution using acetonitrile and 0.1%(volum fraction) formate in water as mobile phases. The analytes were detected by tandem quadrupole mass spectrometry after positive electrospray ionization by multiple reaction monitoring(MRM). External standard method with matrix was used to determine the results. The correlation coefficient was greater than 0.99 for each drugs. The limits of quantitation(LOQ) were 1.5—7.5 μg/kg. The mean recoveries at the three spiked levels of 7.5, 25, 50 μg/kg were 67.3%—117.8%. The relative standard deviation(RSD) were 1.9%—17.4%. The results indicated that using multi-walled carbon nanotubes as solid phase extraction adsorbent was efficient for the purification. The simplicity, sensitivity and good precision of the method made it be well suitable for determination of multi-veterinary drug residues in honey.



UPLC-MS/MS Method for Determination of Uric Acid and Creatinine in Serum and Urine of Hyperuricemic Mice

MA Qing-Shan, WANG Qian, ZHAO Kai-Shu, ZHAI Shu-Bo, LIU Shu, LIU Zhi-Qiang

2013, 34(12):  2716-2720.  doi:10.7503/cjcu20130704

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An ultra-high performance liquid chromatography-triple quadrupole mass spectrometry(UPLC-MS/MS) method for the determination of uric acid and creatinine in serum and urine was established and applied to screening of anti-gout medicines. The automatic sampler and the pump of an LC apparatus were used to inject sample and mobile phase into a chromatography guard column which was used to remove most interference components and enrich the target compounds. MS/MS analysis was carried out in positive ion mode and in multiple reaction monitoring(MRM) mode for creatinine, linearity of the MS/MS assay without and with matrix were 0.03—400 μmol/L and 0.2—400 μmol/L of creatinine, with a limit of detection(LOD) of 0.03 and 0.2 μmol/L, respectively. The uric acid was analyzed in negative ion mode, linearity of the MS/MS assay without and with matrix were 0.1—350 μmol/L and 0.5—300 μmol/L of uric acid, with a LOD of 0.1 and 0.5 μmol/L, respectively. An analytical recovery of this method was 91.8%—103.7% and the RSDs for intra-day and inter-day were less than 5.9% and 6.8% respectively. The results meet the requirements for a bioanalytical assay. Subsequently, the established method was applied to screening of anti-gout medicines. The results showed that ermiaowan, Phellodendri Chinensis Cortex and Atractylodis Rhizoma were able to reduce blood uric acid levels at some degree compared with the positive control drugs, including allopurinol and benzbromarone. In addition, they can significantly reverse the renal damage and protect the renal function.



Study on Fresh Breast Tissues by Near-infrared Raman Spectroscopy

HU Cheng-Xu, ZHENG Chao, ZHANG Hai-Peng, BI Li-Rong, XU Shu-Ping, FAN Zhi-Min, HAN Bing, XU Wei-Qing

2013, 34(12):  2721-2727.  doi:10.7503/cjcu20130131

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A portable Raman spectrometer was used for distinguishing the characteristics of normal, malignant and benign fresh breast biopsy samples. Based on spectral profiles, the presence of lipids(1230, 1268, 1301, 1440, 1743 cm^-1) is indicated in normal tissue. And proteins(amide Ⅰ, and amide Ⅲ, 1246, 1271, 1315, 1364 cm^-1) are found in benign and malignant tissues. Between benign and malignant, nucleic acids(1340 cm^-1) are found to be good discrimination parameters. In the process of data analysis, the model was set up by Gaussian Process with the intensity of the feature, and obtained the specificity(0.94), sensibility(0.95) and Matthews correlation coefficient(MCC, 0.86). This study shows the significance in diagnosing breast disease, and contributes fundamentally to further application on clinic.



Organic Chemistry

Structural Characterization of Purified Polysaccharide Fraction(PLP-1) from the Seeds of Plantago asiatica L.

YIN Jun-Yi, LI Chang, NIE Shao-Ping, XIE Ming-Yong

2013, 34(12):  2728-2733.  doi:10.7503/cjcu20130382

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Polysaccharide's biological activities are related to their structure. Previous studies showed that the polysaccharide from seeds of Plantago asiatica L. had good bioactivities, and two fractions from the crude polysaccharide were characterized. This work aimed at investigating primary structure of another fraction, PLP-1. The methods, including monosaccharide compositions analysis, partial acid hydrolysis, nuclear magnetic resonance(NMR), gas chromatography(GC) and gas chromatography-mass spectroscopy(GC-MS), were applied for structural characterization. The results showed that PLP-1 was composed of Ara(33.98%), Xyl(58.23%), Rha(2.36%), Glc(2.23%), Gal(2.36%) and Man(0.83%). Its main uronic acid was GlcA. The majority residues were α-T-linked Araf(9.58%), β-T-linked Xylp(8.71%), α-1,3-linked Araf(18.22%), β-1,3-linked Xylp(8.05%), β-1,4-linked Xylp(5.85%), β-1,2,4-linked Xylp(16.98%) and β-1,3,4-linked Xylp(27.52%). GlcA was existed as α-T-linked GlcAp. There were other residues, including 1,2-linked Rhap, T-linked Glcp, 1,6-linked Glcp, T-linked Galp, 1,3-linked Galp and 1,3,6-linked Galp, etc. Finally, primary structure of PLP-1 was proposed.



Total Synthesis of Natural Product Luxenchalcone

ZHANG Ying-Peng, ZHANG Wei-Na, YANG Yun-Shang, QIAO Ming

2013, 34(12):  2734-2737.  doi:10.7503/cjcu20130306

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Luxenchalcone was first isolated from the leaves of Luxemburgia octandra in 2004 by Brazil chemists. In 2007 this compound was proved to have significant cytotoxicity on HT-29 colon adenocarcinoma, NCl-H460 non-small cell lung carcinoma, MCF-7 breast cancer cell, OVCAR-3 ovarian adenocarcinoma cells and RXF-393 renal cell carcinoma. But the natural compound has not been synthesized in the literature. In order to synthesize Luxenchalcone, based on the natural product symmetry, the key step was Ullmann reaction, and then the natural product was easily to obtain by aldo condensation. In this work, Luxenchalcone was synthesized by methoxymethylation, bromination, Ullamnn reaction, aldo condenstion, deprotective group from 2,4-bihydroxyacetophone and 4-hydroxybenzaldehyde in 18% overyield. The structure of Luxenchalcone and intermediates were confirmed by ¹H NMR, ¹³C NMR and ESI-MS. The synthesis of this compound maybe gives some vital significance to find lead compounds.



Chemoselective Synthesis of 1,1-Diacetate from Aldehydes Catalyzed by Sulfonated Carbon Nanocage

ZHENG Yan-Jun, LI Jiang, LU Jun-Jin, JIA Yu-Cai, LI Bao-Lin

2013, 34(12):  2738-2744.  doi:10.7503/cjcu20130303

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Acetals are one of the most useful carbonyl protecting groups because of their stability under both neutral and basic media. In addition, acetals can be converted to a variety of other functional groups. Thus, to find a green synthesis method of acetals, the sulfonated carbon nanocage(S-CKT) as a reusable solid acid catalyst was applied to the reaction of aldehydes with acetic anhydride. As a result, a mild and efficient method was developed for the chemoselective preparation of 1,1-diacetates(acylals) from the mixture of aldehydes(2 mmol) and acetic anhydride(5 mmol) catalyzed by S-CKT(30 mg) under room temperature and solvent-free conditions. The reaction takes a shorter time(5—12 min) and gives good to excellent yield(89%—98%). While it is found that ketone doesn't react with acetic anhydride to yield corresponding product under the same conditions. The catalyst was recycled seven times without a distinct loss of activity by simple filtration and washing.



Design, Synthesis and Activity Evaluation of N-Substituted Phthalimide Derivatives

QIN Si-Ning, LÜ Wen-Wen, WANG Quan, ZHAO Qing-Chun, XU Yong-Nan

2013, 34(12):  2745-2751.  doi:10.7503/cjcu20130298

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One novel compound 3,5-dimethoxy phthalimide had been isolated from Lasiosphaera fenzlii Reich. The compound exhibited definite antioxidant activity. Meanwhile it was reported that many compounds with the skeleton of phthalimide displayed many bioactivities such as anti-angiogenesis, anti-inflammatory, immune regulation and anti-tumor and so on. On the comprehensive review of above evidences, a series of N-substituted-3,5-dimethoxy phthalimide derivatives and N-substituted-3,5-dihydroxy phthalimide derivatives were designed and synthesized. Those compounds were synthesized by the multi-step reaction, 3,5-dimethoxybenzoic acid was used as a starting material, and sequentially generates the phthalic anhydride and phthalimide, then reacted with a series of halogenated hydrocarbons, and stripped of methyl to obtain the target compounds. Thirty-one new compounds were synthesized, and the structures were characterized by ¹H NMR, ¹³C NMR and MS techniques. Their anti-tumor and anti-angiogenesis activities against A549 and HUVEC cell line in vitro were tested. Some compounds showed a certain activity.



Synthesis, Characterization and Antidiabetic Activities of Novel Genipin Derivatives

LI Zhi-Wei, BAO Zhi-Chao, WANG Jian-Nan, CAO Rui-Feng, XIE Zhao-Yang, ZHENG Qun-Yi

2013, 34(12):  2752-2758.  doi:10.7503/cjcu20130284

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Diabetes has become the third major diseases threat to human's health and safety after cancer, cardiovascular and cerebrovascular diseases. The currently used drugs are difficult to completely cure the disease, and the long-term use is easy to produce side effects and drug resistance. So, it is very important to research and development a new kind of drug to treat the diabetes. The extract of gardenia and fruit containing the active ingredient genipin showed a very good effect in the traditional Chinese medicine treating the diabetes. In order to find novel anti-diabebes molecules, two core compounds containing amine group were synthesized from the commercial available genipin by methylation(benzylation), substitution with methylsulfonyl chloride followed by sodium azide and reduction. Thirteen novel compounds were obtained by reacting the two core compounds with a variety of acyl chlorides. The total yields were between 41% and 63%. Their structures were characterized by NMR, ESI-MS and elemental analysis and anti-dibiatic activities were evaluated by DPP Ⅳ assay at a concentration of 10 mmol/L. The results showed that all the title compounds exhibited certain extent inhibitory activities against DPP Ⅳ. Among them, compound 10f showed higher inhibitory rate up to 31.2%.



Synthesis of Multiaryl-substituted Mannich Base Catalysed by Silica-supported Rare Earth Samarium Chloride

MA Xue-Lin, ZHANG Xiao-Yong, YONG Sheng-Li, DUAN Li-Ping, WU Zhen-Yu

2013, 34(12):  2759-2764.  doi:10.7503/cjcu20130255

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Many supported-catalysts are applied to the Mannich reaction, but they have disadvantages of low yield, unstability of supported rate and asking for long time. Silica-supported rare earth samarium chloride(SiO₂-OSmCl₂) was prepared by the reaction of silica and rare earth samarium chloride in toluene or CCl₄. The effects of different reaction conditions on the yields were investigated. This protocol has advantages of stability of supported rate, short time, mild condition, high yield, high selectivity, simple work-up, environmental friendly procedure and the catalyst can be reused. The three components of p-methoxyacetophenone, aromatic aldehydes and aromatic amines were reacted by one-pot Mannich reaction and catalysed by SiO₂-OSmCl₂ in ethanol at room temperature. As results, a series of new β-Amino carbonyl compounds were synthesized. The catalyst was characterized via IR and XRD, simultaneously the products were determined by IR, ¹H NMR and elemental analysis.



Fitness of Amorphadiene Production Functional Modules and Yeast Chassis

JIA Yun-Jing, ZHAO Juan, DING Ming-Zhu, YUAN Ying-Jin

2013, 34(12):  2765-2771.  doi:10.7503/cjcu20130339

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The key to construct artificial yeast cells to produce amorphadiene is the fitness of heterologous functional modules and chassis. The fitness of functional modules and chassis were studied by optimization of vectors, protein expression and promoters in the functional modules. Two functional modules constructed with centromere vector and episomal vector were introduced into two engineered chassis overexpressing key genes(a truncated 3-hydroxyl-3-methylglutaryl-CoA reductase gene tHMGR and farnesyl diphosphate synthase gene ERG20) in mevalonate(MEV) pathway, and the highest amorphadiene production was 11.2 mg/L in the artificial cell with better fitness. Amorphadiene synthase gene ADS and ERG20 were fused to construct fusion enzyme modules, and the fitness with the selected chassis were improved, resulted in a higher amorphadiene production of 17.5 mg/L. With promoter engineering(TDH3p, TEF1p, PGK1p) in the fusion enzyme modules, an artificial cell with a better fitness of functional module and chassis reached a 71.8 mg/L amorphadiene production.



Antibacterial Indole Trimer from Metagenomic Library of Marine Sponge Discodermia calyx

HE Rui, WANG Bo-Chu, ZHU Lian-Cai, LIU De-Fang

2013, 34(12):  2772-2777.  doi:10.7503/cjcu20130275

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Marine sponge Discodermia calyx harboring highly complex consortia is a rich and important source of biologically active compounds. Considering the chemical and biological diversity present in the sponge microbial community, the metagenomic library of marine sponges should be an interesting resource to search for unique bioactive small molecules and the corresponding unknown functional genes. Therefore, we constructed the metagenomic library of a marine sponge, Discodermia calyx. Functional screening of this library afforded one antibacterial clone pDC111 by two-layer top agar method. The antibacterial clone pDC111 was cultured and the chemical constituent was analyzed and separated by bioassay-guided fractionation. Compound 1 was afforded and identified as indole trimer by its 1D NMR(¹H NMR, ¹³C NMR), 2D NMR(¹H-¹H COSY, HMQC, HMBC) and HR-TOFMS data. Antibacterial test results showed that compound 1 exhibited anti-Bacillus cereus activity with inhibition zone of 12 mm at 10 μg/paper(i.d. 6 mm). This indicated that functional metagenomics could be used to search for active compounds from marine sponges consisting of large population of uncultured microbes. Furthermore, there are highly potentials that the functional genes of indole trimer 1 could be identified by further molecular biology techniques investigation.



Physical Chemistry

Fabrication of Superoleophobic Copper Surfaces with Low Adhesion and Acid/basic-resistance in Water

CHENG Zhong-Jun, LAI Hua, FU Ke-Wei, ZHANG Nai-Qing, SUN Ke-Ning

2013, 34(12):  2778-2782.  doi:10.7503/cjcu20130842

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A novel superoleophobic copper surface in water with special acid/basic resistant property was reported. When the surface is placed under water, an oil droplet has a high contact angle of about 162°, indicating that the surface is superoleophobic in water. Meanwhile, the surface is low adhesive to the oil droplet, and an oil droplet can roll on the surface easily with a sliding angle of about 3°. Noticeably, the surface has a special acid/basic-resistant property and can retain the low adhesive superoleophobic performance at various pH values(2—12) in water. The low adhesive superoleophobic property in water can be ascribed to the combined effect of the hydrophilicity and the hierarchical structures on the surface, and the acid/basic-resis-tance is due to the chemical stability of copper substrate.



Surface Activity Properties of Chiral L-Lysine Based Gemini Surfactants

LIANG Ya-Qin, HU Zhi-Yong, CAO Duan-Lin, LIANG Dong

2013, 34(12):  2783-2790.  doi:10.7503/cjcu20130731

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Surface activity properties and critical micelle aggregation numbers of [C₁₂-m-C₁₂] Na₂(m=2,4,6) and [C₁₂-T-C₁₂] Na₂ were determined by surface tension, electrical conductivity and steady fluorescene probe methods. The values of critical micelle concentration(cmc), γ_cmc and per surfactant molecule(A_min) derived from surface tension measurement were found to be in the order of [C₁₂-2-C₁₂] Na₂< [C₁₂-4-C₁₂] Na₂< [C₁₂-6-C₁₂] Na₂< [C₁₂-T-C₁₂] Na₂, which were in aggreement with the sequence of Γ_max. The results show that the surface activites of [C₁₂-m-C₁₂] Na₂ and [C₁₂-T-C₁₂] Na₂ are high. ΔG_m⁰ and ΔH_m⁰ are negative, the absolute value of ΔH_m⁰ is much smaller than the product of ΔS_m⁰ and temperature in the aqueous solution. The thermodynamic parameters of micellization of the four Gemini surfactants indicate that the micellization process is an enthopy-driven, exothermic and spontaneous process. As the spacer lengthens from 2 to 6 or the rigidity of the spacer strengthens, which results in a decrease in the ability of micelles to form, ΔG_m⁰ and ΔH_m⁰ of the surfactants increase, ΔS_m⁰ and critical micelle aggregation numbers of the surfactants decrease. The circular dichroism indicated the formation of chiral helical aggregates above the cmc.



Theoretical Study on Redox-adjustable Second-order Nonlinear Optical Responses of 12-Vertex [1-R-CB₁₁-Me₁₁]^- Carborane Complexes

WANG Jiao, ZHANG Meng-Ying, ZOU Hai-Yan, YU Hai-Ling, WANG Wen-Yong, SONG Hong-Juan, LI Xiao-Qian, QIU Yong-Qing

2013, 34(12):  2791-2797.  doi:10.7503/cjcu20130685

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The second-order nonlinear optical(NLO) properties of 12-vertex [1-R-CB₁₁-Me₁₁]^- carborane complexes were investigated with the density functional theory(DFT) method. The results indicate that both the electron-donating or electron-withdrawing substituents and the reversible redox reaction of molecules can affect the molecular geometry. By the force of natural bond orbital(NBO) charge and the electron spin density analysis, we conclude that the molecular oxidation center is in carborane cage. The oxidation reactions of molecules have a significant effect on changing the electronic character of carborane. Meanwhile, the oxidization of the carborane anion is more helpful to enhance the β_tot value, for instance the amino derivative of carborane. Therefore, the redox reaction of this carborane can be used to adjust the second-order NLO response effectively.



Structure Activity Relationship Studies on Novel Acylpiperidine Compounds Based on Insect OBP1

CHEN Wen-Ya, WANG Shan-Shan, LI Dong-Ling, PENG Wei, ZHAO Jing-Fu, DUAN Hong-Xia

2013, 34(12):  2798-2805.  doi:10.7503/cjcu20130656

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The binding mode between 29 novel acylpiperidine compounds and odorant binding protein AgamOBP1 were studied with Sybyl7.3 software. The results show that the hydrophobic effect and the water-bridge interaction both mainly contribute to their binding affinity. Some terminated hydrophobic groups of these acylpiperidine compounds are indicated to be embed a hydrophobic, long and narrow tunnel in the binding pocket of AgamOBP1. Their acyl O forms multiple hydrogen bonds with some key residues Trp114 and Gly92 or Cys95 of AgamOBP1 via a water-bridge interaction with HOH153. The comparative molecular field analysis(CoMFA) and comparative molecular similarity indices analysis(CoMSIA) were used to build the 3D-quantitative structure-activity relationship(QSAR) models of acylpiperidine compounds. Cross-validation coefficients(r_cv²) of the obtained CoMFA and CoMSIA models are 0.650 and 0.587, respectively. In the best CoMSIA model, the hydrophobic, electrostatic and steric field effects are found to be important factors for the repellent activities of these acylpiperidine compounds, especially the hydrophobic effect. The structure-activity relationship of acylpiperidine compounds is revealed based on the binding pocket feature of AgamOBP1 and their 3D-QSAR models. These acylpiperidine compounds with a 9 or 10 carbon chain are indicated to be the best one in the repellent ability when the substituent group in their piperidine ring is identical in the size and position. The introduction of a bulky substituent group in the piperidine ring is shown to be unfavorable to the repellent activities of these acylpiperidine compounds with the same long hydrophobic carbon chain because of the size limitation of the AgamOBP1 binding pocket. The acyl group of these acylpiperidine compounds as a hydrogen donor group is proposed to be necessary for recognizing and binding to AgamOBP1. These studies will provide a theoretical foundation for the bio-rational design of novel acylpiperidine repellent molecules.



Hydrodeoxygenation of Guaiacol over Nickel-based Catalyst Supported on Mixed Oxides

KONG Wei, ZHANG Xing-Hua, ZHANG Qi, WANG Tie-Jun, MA Long-Long, CHEN Guan-Yi

2013, 34(12):  2806-2813.  doi:10.7503/cjcu20130651

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Using bimetal mixed oxides Al₂O₃-SiO₂, Al₂O₃-TiO₂, TiO₂-SiO₂ and TiO₂-ZrO₂ as supports, nickel catalysts were tested through hydrodeoxygenation(HDO) reaction of guaiacol and characterized by Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD), NH₃ temperature programme desorption(NH₃-TPD) and H₂ temperature programme reduction(H₂-TPR) techniques. The effects of support, solvent, reaction temperature and pressure on conversion of guaiacol and selectivity of different products were studied. The resistance of coke, recyclability of catalyst and the reaction mechanism for guaiacol hydrodeoxygenation were also discussed. The results show that the activities of Ni/TiO₂-ZrO₂ are obviously better than the others under the same reaction conditions. The conversion of guaiacol over Ni/TiO₂-ZrO₂ catalyst is 100% and the selectivity for cyclohexane is as high as 86.4% under the optimization condition of 300 ℃ and the initial H₂ pressure of 4 MPa in decalin. Moreover, the Ni/TiO₂-ZrO₂ catalyst has a better performance of anti-coking than traditional catalysts, about only 3.2%(mass fraction) of residual cokes on the catalyst surface.



Synthesis, Characterization and Catalytic Fuel Ultra-deep Desulfurization of Hollow Amino-SiO₂ Supported Heteropoly Compound Catalyst

LIU Ri-Jia, WANG Rui

2013, 34(12):  2814-2820.  doi:10.7503/cjcu20130641

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Hollow SiO₂ was prepared by dispersion aggragation before uploading HPW. The prepared catalyst was characterized by N₂ adsorption-desorption, FTIR, XRD and SEM. The method of catalytic extraction fuel ultra-deep desulfurization was developed using hydrogen peroxide as oxidant and MeCN as extractants. The effects of catalyst dosage, O/S molar ratio, pre-immersion time of the catalyst in H₂O₂ solution, reaction temperature and initial sulfur content were investigated. Under the favourable operating conditions recommended as follows: mass ratio of catalyst dosage and simulated diesel of 1.0%, O/S molar ratio of 15, pre-immersion time of the catalyst in H₂O₂ solution being 4 min, temperature of 60 ℃ and initial sulfur content of 350 mg/L, the sulfur content of simulated diesel can be reduced from 350 mg/L to 2.45 mg/L, with a desulfurization efficiency of 99.3% at 180 min. The overal desulfurization efficiency reaches 99.3%, higher than that by mere extraction by 45.1%, efficiency significantly. Moreover, NH₄PW-SiO₂ for real gasoline and diesel catalytic oxidative desulfurization was obtained with good effect and the catalyst recovered demonstrates almost the same activity as the fresh after 5 recycles.



Synthesis and Theoretical Studies of 1,2,3-Triaminoguanidinium Dinitroguanidinate Salt

JIN Xing-Hui, HU Bing-Cheng, JIA Huan-Qing, LIU Zu-Liang, LÜ Chun-Xu

2013, 34(12):  2821-2826.  doi:10.7503/cjcu20130602

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A new energetic ionic salt1,2,3-triaminoguanidinium dinitroguanidinate salt was synthesized based on 1,2,3-triaminoguanidinium hydrochloride and dinitroguanidine. The optimized structure, IR spectrum and thermodynamic parameters were obtained at the DFT-B3LYP/6-31+G^** theoretical level. Its detonation properties were also predicted by the formula of Kamlet-Jacobs. The results show that the density, heat of formation, detonation velocity and detonation pressure are 1.56 g/cm³, 150.54 kJ/mol, 7.81 km/s and 24.74 GPa, respectively.



Organic Chemistry

Fabrication and Photocatalytic Property of ZnO/Ag Microspheres

ZHANG Zhen-Fei, LIU Hai-Rui, ZHANG Hua, LIU Xu-Guang, JIA Hu-Sheng, XU Bing-She

2013, 34(12):  2827-2833.  doi:10.7503/cjcu20130598

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ZnO/Ag microspheres were synthesized on the basis of as-prepared ZnO microspheres by microwave-assisted polyol method. The microstructures, morphologies and optical properties of the samples were characterized by X-ray diffractometer(XRD), scanning electron microscope(SEM), transmission electron microscope(TEM), UV-Visible absorption spectrometer(UV-Vis) and photoluminescence spectrometer(PL). The photocatalytic activities of the samples were tested with the photocatalytic degradation of methylene blue. Results demonstrate that the surfaces of wurtzite ZnO spheres are coated by very small face-center-cubic Ag nanoparticles; ZnO/Ag composites have strong absorption in the UV and visible light range and the absorption band shows some red-shifts compared to the ZnO microspheres. With the increase of Ag content, the photoluminescence intensity of ZnO/Ag composites decreases firstly and then increases; ZnO/Ag composites exhibit higher photocatalytic activity than ZnO particles; however, the ZnO/Ag composite prepared with AgNO₃ concentration of 0.05 mol/L has the highest photocatalytic activity.



Physical Chemistry

Preparation of Electrostriction of PANI/PU Concave Lens Array by Solvent Evaporation Self-organization

JIA Ruo-Kun, ZHOU Shi-Yu, LIN Song-Zhu, HE Ai-Min, BAI Yu-Bai

2013, 34(12):  2834-2840.  doi:10.7503/cjcu20130577

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Ordered porous membrane with specific morphology were prepared by solvent evaporation self-organization using water drops as the template. The polyaniline/polyurethane(PANI/PU) concave lens array was prepared by the above ordered porous membrane. FTIR and SEM were employed to study the structure of PANI/PU nanocomposite which was synthesized by interfacial polymerization and the morphology of the concave lens array. The effect of different synthesis conditions on the conductivity of PANI/PU nanocomposite were studied, and also discussed the electrical properties and optical performance of PANI/PU concave lens array. The results indicated that the PANI/PU concave lens array had electrical conductivity, while exhibited electrical contractility and the properties of light diffraction; the shrinkage of PANI/PU film is inversely proportional to voltage, and the transmittance is proportional to the shrinkage.



Effect of Ion Exchange Membrane on Pentachlorophenol Degradation by Biofilm-electrode Method

ZHANG Xue-Na, ZHONG Xin-Wen, LIU Ming-Yu, LI Chen, LIN Hai-Bo

2013, 34(12):  2841-2844.  doi:10.7503/cjcu20130421

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Effect of ion exchange membrane on pentachlorophenol degradation by biofilm-electrode method was studied. It was found that the use of anion exchange membrane had the better results for the PCP conversion and the intermediaters removal compared to the use of cation exchange membrane. In an electrolytic cell consisted of Ti/PbO₂ anode, biofilm-electrode cathode and the anion exchange membrane diaphragm, the biofilm electrode method has much better results for the PCP degradation rate and the intermediate removal compared to the biological and electrochemical methods. The PCP degradation rate and the chemical oxygen demand(COD) removal rate can both reach 96%(mass fraction) in a treatment period of 24 h.



Preparation and Enhanced Electrocapacitive Properties of Polyaniline Nanothorns on the Surface of Nitrogen-doped Hollow Carbon Spheres

GAO Lei, LIAO Yi, ZHANG Xiao-Hua, CHEN Jin-Hua

2013, 34(12):  2845-2849.  doi:10.7503/cjcu20130366

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Polyaniline/nitrogen-doped hollow carbon spheres(PANI/N-HCS) nanocomposites were prepared via in situ polymerization of nano-sized polyaniline thorns on the surface of nitrogen-doped hollow carbon spheres. The morphology and structure of PANI/N-HCS were characterized by SEM, TEM and FTIR, respectively. The electrochemical capacitive behavior of PANI/N-HCS was investigated by cyclic voltammetry, chronopotentiometry and electrochemical impedance spectroscopy in 1 mol/L H₂SO₄ solution. The specific capacitance of PANI/N-HCS is 346 F/g at 0.5 A/g, which is higher than that of each individual component. In addition, PANI/N-HCS shows excellent power characteristics: the specific capacitance is as high as 228 F/g when the current density increases to 20 A/g, and the specific capacitance retains 66% compared to that of 0.5 A/g. The specific capacitance retains 76% after 1000 charge-discharge cycles.



Studies on Electrochemical Oxidation Reaction of 2,4-Dichlorophenol on Pt Electrode

MA Chun-An, WANG Fen, LU Jin-Jin, LI Mei-Chao, ZHENG Wan-Fang

2013, 34(12):  2850-2854.  doi:10.7503/cjcu20130326

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Cyclic voltammetry(CV) and in situ FTIR spectrometry were employed to study the electrochemical oxidation mechanism of 2,4-dichlorophenol(2,4-DCP) in NaOH solution. Density functional theory(DFT) was used to calculate the Fukui function for 2,4-DCP and gave the information on possible reactive sites of 2,4-DCP during electrochemical oxidation. CV results show that the Pt electrode exhibits a high electrochemical activity for the electrochemical oxidation reaction of 2,4-DCP. On the basis of in situ FTIR data, the electrochemical oxidation reaction of 2,4-DCP is as follows: (1) C—Cl band of 2,4-DCP is broken to form phenol directly; (2) C—Cl band of 2,4-DCP is broken and C—O band is formed with ·OH radicals, and the Fukui function results show that chlorine atom at 4 position is easier to be replaced with the hydrogen or ·OH radicals. Then hydroxylation reaction happens on the C4-position of phenol leading to form hydroquinone which is subsequently electrochemically oxidized to benzoquinone. With the potential increasing, aliphatic carboxylic acids are formed after the ring cleavage; (3) part of 2,4-DCP is electrochemically oxidized to chloromaleic acid directly. At about 1700 mV, CO₂ could be formed during electrochemical oxidation reaction of 2,4-DCP on Pt electrode.



One-step Flame-assisted Pyrolysis Synthesis of Fe Doped Carbon Incorporated TiO₂ and Its Photocatalytic Activity

CHEN Xi, LI Hui, SUN Tong, CUI Xiao-Li

2013, 34(12):  2855-2860.  doi:10.7503/cjcu20130314

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Fe doped carbon incorporated TiO₂ was synthesized with a simple and facile one-step flame-assisted pyrolysis method and its photocatalytic properties were characterized by degradation of methylene blue(MB). The morphology, components, crystalline structure and absorbance of as-prepared samples were characterized by SEM, EDX, XPS, XRD and UV-Vis DRS, respectively. EDX and XPS results show that Fe³⁺ was introduced into TiO₂ lattice by substituting Ti⁴⁺. XRD patterns reflect that mainly anatase TiO₂ was obtained directly without any annealing. The absorbance edges show red shifts, and absorbance of visible light enlarge with increasing Fe amount, indicating the narrowed optical band gap with the introduce of impurity energy levels. SEM results show that the uniform micro spherical shapes of carbon incorporated TiO₂ were damaged with the introduction of Fe. The promoted photocatalytic activity of samples for the degradation of MB was observed under both visible light and UV-Vis light irradiation with Fe doping not more than 0.2%. The highest photocatalytic degradation rate for MB was observed for the sample with 0.1%(molar fraction) Fe. The photocatalytic activity decreased when the Fe doping amount reached to 0.3%.



Thermodynamic Studies on Catalytic Reaction Between Bromelain and Soybean Protein

LI Xiang-Yang, DONG Hai-Zhou, ZHANG Hong-Lin

2013, 34(12):  2861-2865.  doi:10.7503/cjcu20130292

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The power-time curves of reaction between bromelain and soybean protein were determined using microcalorimeter. Using the thermodynamic theory and reduced extent method, the Michaelis constant(K_m) and the maximum velocity(V_max) of catalytic reaction were obtained at different temperatures and pH values, and the equations from the relation between K_m and temperatures(K_m-T), and pH values(K_m-pH) were established. Based on the established equations, the optimum temperature(314.63 K) and the optimum pH(6.99) were gained. Under the optimum temperature and pH, the power-time curves of catalytic reaction with metal ions were obtained, and the apparent Michaelis constant(K_m') and the maximum reaction velocity(V_max') were gained. The relations between the K_m' and the contents of metal ions were established. Compared with the K_m and V_max, the activation or inhibition effect of metal ions on enzymatic reaction could be known.



Polymer Chemistry

Preparation of Magnetic Drug Carriers with Evodiamine and Fe₃O₄ Nanoparticles Co-encapsulated

WANG Yan, WANG Xiao-Ying, LV Yan-Yun, XU Wen-Bin, GUO Yi, XU Li

2013, 34(12):  2866-2870.  doi:10.7503/cjcu20130807

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Evodiamine and Fe₃O₄ nanoparticles were co-encapsulated by dialysis method with methoxy poly(ethylene glycol)/poly(lactide-co-glycolide)(mPEG-PLGA) as carriers. The magnetic drug carriers were characterized through transmission electron microscope(TEM), Fourier transform infrared spectrum(FTIR), UV-Vis spectrum(UV), in vitro release action, Prussian blue staining, in vitro cytotoxicity and magnetic targeting study. The data suggested that Fe₃O₄ nanoparticles and drug loaded micelles were spherical morphology with narrow size distribution, and had high entrapment capacity with slow release in vitro release profiles. Furthermore, the Fe₃O₄ nanoparticles and drug loaded micelles were safe and had magnetic targeting properties.



Synthesis and Properties of Intermolecular Self-crosslinking Organic-inorganic Hybrid Waterborne Polyurethane Based on CuAAC Reaction

LI Xing-Jian, HU Jing, SUN Dao-Xing, ZHANG Yi-Heng

2013, 34(12):  2871-2879.  doi:10.7503/cjcu20130789

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A series of waterborne polyurethane(WPU) bearing the varying quantities of alkyne functions as pendant groups located along the backbone was synthesized via the 4,4'-bis(hydroxymethyl)-1,4-heptadiyne functional monomer as a chain extender. The room temperature intermolecular self-crosslinking organic-inorganic hybrid WPU was prepared based on the Cu(Ⅰ)-catalyzed azide-alkyne cycloaddition(CuAAC) reaction between alkyne-functionalized WPU and azide propyltriethoxysilane(APTES-N₃). The self-crosslinking organic-inorganic hybrid WPU was prepared, which was confirmed by FTIR and ¹H NMR. The influences of the grafting amount of APTES-N₃ on properties of the WPU films and the emulsion particle morphology of WPU were studied. The results indicate that with the increase of APTES-N₃, crystallinity of the WPU films decreased and resistance to water, solvent resistance and thermal stability of the WPU films increased, and the degree of mutual adhesion of emulsion particles enhanced. As the mass fraction of APTES-N₃ increases from 0 to 12%, the tensile strength of the WPU film increases from 14.3 MPa to 28.6 MPa. Synthetically taking into account the emulsion stability, water resistance and mechanical properties of WPU, when the mass fraction of APTES-N₃ is 12%, the integrative performances of WPU is the best.



Preparation and Properties of Molecularly Imprinted Nanofiber Memberanes Towards Enrofloxacin

WANG Yan-Ling, LIU Jun-Bo, TANG Shan-Shan, CHANG Hai-Bo, LIANG Da-Dong

2013, 34(12):  2880-2886.  doi:10.7503/cjcu20130787

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Enrofloxacin(ENRO) molecular imprinted polymers(MIPs) obtained via precipitation polymerization were added to the polyvinyl alcohol(PVA) aqueous solution. Then electrospinning technique was employed to prepare ENRO molecularly imprinted nanofiber membranes(MINFMs). We investigated the effects of concentration of PVA solution, applied voltage, and the distance between the needle and collector on the diameter and morphology of the nanofiber membrane via scanning electron microscope(SEM) measurement. The swelling ratio, void ratio, adsorption property, and adsorption selectivity of membrane were also studied. The optimal electrospinning process was carried out at environmental temperature of 25 ℃ and relative humidity of 40%—50%, with PVA concentration of 7.0%(mass fraction), spinning voltage of 15 kV, and the distance between the needle and collector of 25 cm. Under such conditions, the fibers in MINFMs were uniform with diameters of about 180 nm. The swelling rate and void ratio of the as-prepared MINFMs were 136.76% and 33.42%, respectively, which were more than those of non-imprinted nanofiber membranes(NINFMs). The dynamic adsorption experiments of MINFMs showed that the adsorption reaction reached balance after 300 min. Analysis of the Scatchard plot revealed that the binding sites of MINFMs to ENRO were equal class under the studied concentration range, the dissociation constant(K_d) and apparent maximum adsorption quantity(Q_max) of MINFMs were 505.817 mg/L and 3.862 mg/g, respectively. The specific absorption capacity of MINFMs to ENRO was higher than those of ciprofloxacin(CIP) and ofloxacin(OFL).



Synthesis, Characterization and Solution Properties of PAAH Copolymer Containing Capsaicin-like Moieties

JIA Lan-Ni, YU Liang-Min, DONG Lei, ZHANG Qi, WU Xiao-Jing, ZHANG Zhi-Ming

2013, 34(12):  2887-2895.  doi:10.7503/cjcu20130630

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A series of hydrophobically associating PAAH[P(AM-NaAMPS-HMBA)] copolymers was prepared through micellar copolymerization with acrylamide(AM) and 2-acrylamide-2-methylpropane sulphonate(NaAMPS) as hydrophilic comonomers and capsaicin-like N-(4-hydroxy-3-methoxy-benzyl) acrylamide (HMBA) as the hydrophobic comonomer. The structures of PAAHs were identified by UV-Vis, ¹H NMR and SEM. The TGA and AFM were employed to study the thermal stability and the morphology of PAAH aqueous solution. The solution behavior was examined with respect to copolymer concentration, hydrophobe content and temperature. Also, the solubility property and antibacterial activity were investigated. The results show that the content of hydrophobic comonomer in PAAHs coincides approximately with its feed ratio. PAAH exhibits instant solubility and the solution viscosity increases sharply when the polymer concentration surpasses critical associating concentration(c^*). Observations from AFM confirmed the existence of associative structures in PAAH aqueous solution and the intermolecular hydrophobic association is enhanced as hydrophobe content increases. Compared with unmodified PAA, incorporation of HMBA greatly improves the thermal stability of PAAH. Moreover, PAAH is endowed with considerable antibacterial activity against Escherichia coli and Staphylococcus aureus.



Phase Behavior of PS/PVME/SiO₂ Blends Under Oscillatory Shear Flow Field

LI Nan, HUANG Ya-Jiang, XIA Tian, YANG Qi, LI Guang-Xian

2013, 34(12):  2896-2902.  doi:10.7503/cjcu20130454

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The thermodynamics of polystyrene/poly(vinyl methyl ether)(PS/PVME) blends under oscillatory shear flow field were studied in the presence of hydrophilic fumed silica nanoparticles via online optical-shear technique. Similar to that observed in steady shear flow, it was found that there also existed a critical oscillatory frequency below which shear-induced demixing(SID) behavior was found while above which shear-induced mixing(SIM) behavior was presented. The addition of silica nanoparticles improved the miscibility of composites. There existed a critical nanoparticle content above which the oscillatory shear induced mixing and the critical oscillatory frequency behavior disappeared. The behavior showed a strong dependence both on the heating rate and the blend composition.



Effect of MgAlZnFe-CO₃ LDHs on Fire Retardancy and Mechanical Properties of Intumescent Flame Retardant Poly(butylene succinate) Composites

LIU Yue-Jun, MAO Long

2013, 34(12):  2903-2910.  doi:10.7503/cjcu20130419

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MgAlZnFe-CO₃ layered double hydroxides(LDHs) with different proportions of metal ions were prepared by the constant pH coprecipitation method. Ammonium polyphosphate(APP), melamine(MA), and MgAlZnFe-CO₃ LDHs were added in poly(butylene succinate) via melt blending to obtain the novel intumescent flame retardant poly(butylene succinate)(IFR-PBS) composites with MgAlZnFe-CO₃ LDHs as a synergistic agent. The synthesized MgAlZnFe-CO₃ LDHs were characterized by X-ray diffraction(XRD), Inductive coupled phasmamass spectrometer(ICP) and scanning electron microscope(SEM). Consequently, the layered structures of the synthesized MgAlZnFe-CO₃ LDHs were observed. The fire retardancy and mechanical properties of the novel IFR-PBS composites were also evaluated. Compared to those of IFR-PBS composites without MgAlZnFe-CO₃ LDHs, the limiting oxygen index(LOI) values of the novel IFR-PBS composites increased from 30% to 35% and the vertical flammability(UL-94) reached V-0 rate when the content of MgAlZnFe-CO₃ LDHs was 1%(the total loading of flame retardant was 20%). Importantly, the tensile strength and flexural strength of the novel IFR-PBS composites could be enhanced by the presence of MgAlZnFe-CO₃ LDHs.