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    10 April 2008, Volume 29 Issue 4
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    高等学校化学学报2008年第29卷第4期目次
    2008, 29(4):  0.  doi:
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    综合评述
    Advance in Real-time and Dynamic Biotracking and Bioimaging Based on Quantum Dots
    WANG Yang, DENG Yu-Lin, QING Hong, XIE Hai-Yan*
    2008, 29(4):  661-668.  doi:
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    New development opportunities for ultra-sensitive, in situ, real-time and dynamic imaging in life sciences are emerging with fluorescent semiconductor quantum dots(QDs), which are of unique fluorescence properties and have been successfully applied in biological labeling and imaging. Nowadays, QDs-based labeling and imaging is one of the most important frontiers in biodetection and bioimaging. In this paper, the related photophysical properties of quantum dots, recent advance in the preparation of QDs-based fluorescent bioprobes and their applications in real-time and dynamic tracking and imaging are reviewed.
    研究论文
    Synthesis of Ag Nanoparticles via Green Chemistry Method and Their Enhancing Effects on Room Temperature Phosphorescence of Fluorescein
    LI Yu-Qi1, ZHU Ya-Xian1, ZHANG Yong2*
    2008, 29(4):  669-672.  doi:
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    Silver nanoparticles were synthesized via a “green chemistry method”, in which [Ag(NH3)2]+ was reduced by β-D-glucose in the presence of β-cyclodextrin(β-CD), and characterized by UV-Vis, HRTEM and FTIR. Enhanced room temperature phosphorescence(RTP) signal of fluorescein on the filter paper surface in the presence of silver nanoparticle was firstly observed. Furthermore, with the increment of Ag nanoparticles’ concentration, the RTP intensity of fluorescein was increased at first, and then decreased when the molar ratio of fluorescein to Ag nanoparticles reached 1∶2. The mechanism of the interaction between Ag nanoparticles and β-CD was proposed, and the enhancing effects of Ag nanoparticles on room temperature phosphorescence of fluorescein were discussed.
    Effects of Doping Lanthanide Ions in YAG∶Ce System on the Spectral Properties of Ce3+
    KONG Li1, GAN Shu-Cai1, HONG Guang-Yan2*, YOU Hong-Peng2, ZHANG Ji-Lin2
    2008, 29(4):  673-676.  doi:
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    (Y0.95Ln0.01Ce0.04)3Al5O12 phosphors were synthesized by high-temperature solid state reaction under reducing atmosphere and the doping effects of lanthanide ions(Ln3+) on the luminescence properties of phosphors were studied. YAG∶Ce,Ln spectra of excitation and emission show that the influence between Ce3+ and Ln3+ can be divided into the following three types: (1) The Ce3+ emission intensities are decreased slightly in the YAG∶Ce doped with La3+, Gd3+ and Lu3+, respectively. (2) Because of the energy transfer and competitive absorption, for Pr3+, Sm3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+ co-doped YAG∶Ce, the Ce3+ emission intensities are observably decreased. In the YAG∶Ce,Pr system, the emission of Pr3+ is at 609 nm; and in the YAG∶Ce,Sm system, the emission of Sm3+ is at 616 nm. So it can increase the color rendering index(CRI) of YAG∶Ce doped with Pr3+ or Sm3+. (3) It was found that doping with Eu3+, Yb3+ and Nd3+in YAG∶Ce the Ce3+ emission intensities quenched strongly.
    Preparation and Characterization of Neodymium-doped Oxyfluoride Glass-ceramics
    ZHANG Hong-Bo1, SU Chun-Hui1,2*, WANG Yi-Min1, SHAO Jing1, XU Su-Lian1, ZHU Xiao-Wei2, ZHANG Hua-Shan1
    2008, 29(4):  677-680.  doi:
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    Nd3+-doped transparent oxyfluoride glass ceramics containing CaF2 was prepared through controlled crystallization of melt-quenched glass. The sample is characterized by DTA, XRD and FEG-ESEM. The result indicates that the main phase of crystal is CaF2 and the crystalline particle size is 15 nm. The optical transmittance is about 78%—87% in the visible region and 84%—93% in the near-infrared region. Fluorescence measurements exhibit a stronger emission especially at 1060 nm in the glass ceramics than in the precursor glass, and a larger excited emission section value than the precursor glass, due to the incorporation of Nd3+ into CaF2 during the crystallization.
    Hydrothermal Synthesis of Cysteamine-stabilized CdTe Quantum Dots
    YANG Wei-Hai, LI Wan-Wan, SUN Kang*
    2008, 29(4):  681-685.  doi:
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    A facile hydrothermal approach to synthesize high quality cysteamine-stabilized CdTe quantum dots(QDs) was presented. By this approach, the quantum yield(QY) of the resultant QDs can reach as high as 19.7%, which is nearly double-fold of those reported by the former researchers. The effects of the variables on the photoluminescence property of as-prepared CdTe QDs were studied, and the pH-dependent optical properties of as-prepared CdTe QDs were also investigated.
    Synthesis and Crystal Structure of One-dimensional Chain Coordination Polymer [Mn(9-AC)2(4,4'-bpy)(H2O)2]n
    ZHAO Guo-Li1, WU Ying1, YE Jun-Wei2, YE Kai-Qi1*
    2008, 29(4):  686-689.  doi:
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    Hydrothermal reactions of Mn(Ⅱ) acetate, 4,4'-bipyridyl(bpy) with anthracene-9-carboxylic acid(9-HAC) resulted in a new coordination polymer [Mn(9-AC)2(4,4'-bpy)(H2O)2]n. The coordination polymer was characterized by ICP, IR, TGA and single-crystal X-ray diffraction analysis(Mo Kα). The crystal crystallizes in an orthorhombic system, space group Fdd2, a=1.66772(12) nm, b=3.36471(16) nm, c=1.1687(4) nm, V =6.558(2) nm3, Z=8, Mr=689.60, Dc=1.397 Mg/m3, R=0.0356, wR2=0.0604. The Mn centers in the frameworks adopt slightly distorted octahedral coordination geometry, and is bridged by 4,4'-bpy ligands to form one-dimensional straight chain structure. The chain packing in the compound gives rise to three-dimensional structure based on weak coordination bond, hydrogen bonding interactions.
    Determination of Total Safflower Yellow Pigments in Carthamus tinctorius L. by Dynamic Ultrasonic Extraction Coupled with On-line Spectrophotometric Detection
    HU Xiu-Li1,2, YOU Jing-Yan1, ZHANG Han-Qi1, ZHANG Hua-Rong1, MENG Xiang-Zhe1, XIAO Ting-Ting1, FAN Yu-Zhen1, WANG Ying1, YU Ai-Min1*
    2008, 29(4):  690-693.  doi:
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    A dynamic ultrasonic extraction(DUE) coupled with on-line detection by spectrophotometry was proposed for the determination of total safflower yellow pigments(calculated against safflor yellow A) in Carthamus tinctorius L. The extraction was performed in a common self-made extraction vessel placed inside an ultrasonic bath and a peristaltic pump was used to deliver the solvent. Several parameters of DUE, including flow rate of extraction solvent, ultrasonic power and sample amount, were optimized. Compared to the off-line method, the on-line approach has the advantages of minimum sample amount(5 mg), on-line monitoring the extraction process and time-saving(10 min) and the method is more convenient for rapid optimization of the extraction process.
    Interactions Between Fluoroquinolones and Bovine Serum Albumin by Fluorescence Method and Affinity Capillary Electrophoresis
    ZHANG Li-Wei, ZHANG Xin-Xiang*
    2008, 29(4):  694-699.  doi:
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    The interactions between fluoroquinolones(sparfloxacin, lomefloxacin, norfloxacin, levofloxacin, fleroxacin and pefloxacin) and bovine serum albumin were investigated by affinity capillary electrophoresis and fluorescence quenching method. The binding molar ratio was 1∶1 and the values of binding constants were all at the magnitude level of 104 L/mol. Both van der Waals interaction and hydrogen bonds were involved in the binding process of these fluoroquinolones to BSA. The ACE results also reveal that with the increasing of buffer pH values and ionic strength, the interaction strength became weaker to a certain extent. The FL results and UV-Vis spectrum indicate that the fluorescence quenching was mainly arisen from static quenching by complex formation. The obtained results of these two methods may help us in gaining some insights on possible fluoroquinolones/BSA interactions and in evaluating the drugs’ pharmacokinetic profiles.
    Studies on Kinetics of Different Types of Probing Species Through Self-assembled Monolayers on a Gold Electrode by SECM
    CHEN Zhong, SHEN Li, XIE Shu-Bao, HE Sha-Li, JING Ping, XU Xiao-Dong, SHAO Yuan-Hua*
    2008, 29(4):  700-704.  doi:
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    In this paper, the kinetic behavior of mediators with different polarities at n-alkanethiol modified gold electrode are investigated by scanning electrochemical microscopy(SECM). Ferrocyanide[K4Fe(CN)6] and N,N,N',N'-tetramethyl-p-phenylenediamine(TMPD) are employed as the mediators, and the self-assembled monolayers(SAMs) act as a better blocking barrier for the transport of ferrocyanide than that of TMPD. This difference is mainly because of the better permeation of TMPD into the hydrophobic monolayers. A simple model is applied to extract the kinetic rate constants of the permeation step. On the basis of the kinctic rate constants obtained, we can deduce that the equilibriums exist before and after the electronic transfer(ET) when using TMPD, and the apparent kinetic constant is larger than ferrocyanide in this step. The tunneling decay constant of the TMPD in the SAMs, β, can be measured to be equal to 1.2 per methylene group.
    Photoconversion of p-Chlorophenol in Ice and the Presence of Nitrite
    KANG Chun-Li*, GAO Hong-Jie, GUO Ping, TANG Xiao-Jian, ZHANG Ge-Shan, LIU Xing-Juan, DONG De-Ming
    2008, 29(4):  705-709.  doi:
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    Environmental photochemistry of organic pollutants is an important research field, but the ice photochemistry of organic pollutants is still a unknown field and it is attracting more and more attention recently. The ice photochemistry of p-chlorophenol(4-CP), as an important pollutant, is studied a little. In this paper, the UV lamp(125 W high-pressure mercury lamp) was lamp-house and the photoreaction of 4-CP in ice was the object of this research. Some influencing factors and the kinetics and mechanism of the photoconversion was investigated in the range of the temperature of -12—-14 ℃ in the presence of nitrite. According to the results, the initial concentration of the 4-CP, the initial concentration of the nitrite, a commen photoreaction reagent in environment, the initial pH and the intensity of the light had serious effects on the conversion of the 4-CP. The disposal rates of 4-CP and TOC in ice respectively reached 80% and 32% within 180 min. Four reaction products are characterized by MS-GC analysis, it is not completely the same as that reported by other researchers. On this basis the photoconversion mechanism of 4-CP is deduced. It is concluded that the mechanism and photoproducts of 4-CP photoconversion in ice would be changed because of the presence of NO2-.
    Spectroscopic Study on the Recognition Mechanism Between Matrix Metalloproteinase-16 and Natural Flavonoids
    JIA Shu-Yan1, JI Hai-Tao2, FANG Xue-Xun2, WU Yu-Qing1*
    2008, 29(4):  710-713.  doi:
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    Acting on a broad spectrum of extracellular, intracellular, and membrane-associated substrates, the matrix metalloproteinases(MMPs) are critical to the biological processes of organisms. And when aberrantly expressed, many pathological conditions may be born or exacerbated. Several natural flavonoids were used as the inhibitors of MMP-16, and the fluorometric titration and UV-Vis absorption spectra were performed to reveal the recognition and inhibition mechanism between them, large differences at binding model, stoichiometry and antioxidation were clarified between them.
    Metabonomic Study of Hepato-protective Effect of Silybin for the Carbon Tetrachloride Induced Liver Injure in Mice
    HUANG Xin, GONG Yi-Fei, WANG Yi*, QU Hai-Bin, CHENG Yi-Yu
    2008, 29(4):  714-719.  doi:
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    A metabonomic study for the carbon tetrachloride(CCl4) induced liver injure and the hepato-protective effect of silybin in mice was described. Gas chromatography-mass spectrometry(GC-MS) technique was used to analyze the mice metabonome both in liver tissue extraction and plasma. Orthogonal partial least square-discriminant analysis(OPLS-DA) was processed to analyze the metabonome difference between the control and CCl4 treated samples. Twelve metabolites were selected both in mice liver tissue and plasma metabonome, respectively, via the parameter of variable importance in the projection(VIP). Principle component analysis(PCA) was employed to process the data from the preventive and therapeutic treatment of silybin for CCl4 induced hepatotoxicity, and the hepato-protective effect of silybin was investigated through the selected responsor metabolites. The amino acids metabolism, energy metabolism and lipids metabolism were seriously disturbed after CCl4 treatment. Silybin could effectively alleviate the mitochondria dysfunction and the perturbation of amino acids metabolism. The results obtained suggest that metabonomic studies could better reflect the whole status of metabolism in bio-systems, and could be treated as a potential powerful approach in toxicological and pharmacological studies.
    Determination of Trace Amount Methylene Blue Based on [MeCl4]--MB Ionic Associate by Solvent Extraction-fluorophotometry
    YANG Ji-Dong1,2, SHI Wen-Bing2, LIU Shao-Pu1*
    2008, 29(4):  720-725.  doi:
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    In HCl medium, AuCl4- and GaCl4- could react with methylene blue(MB) to form two ionic associates, which could be easily extracted by 1,2-dichloromethane solvent and resulted in the fluorescence enhanced significantly in organic phase. Their maximum excitation wavelengths(λex) located at 656 and 666 nm, respectively; and their maximum emission wavelengths(λem) were 674 and 685 nm, respectively. The synchronized fluorescence spectra(Δλ＝0) could be recorded with synchronous scanning at λex=λem, and it could be proved by the fluorescence polarization experiment that they were resonance fluorescence. The resonance fluorescence peaks of two ionic associates located at 660 and 671 nm, respectively, which was found in the intersection of excitation spectra and the emission spectra. Both intensities(ΔF) of fluorescence and resonance fluorescence were directly proportional to the concentration of MB in a certain ranges, so the high sensitivity methods of determination of trace amount MB were established, and their detection limits(3σ) were 0.2 and 0.6 ng/mL for fluoresence method, as well as 1.1 and 2.8 ng/mL for resonance fluoresence method, respectively. The fluorescence method has a higher sensitivity and is more suitable in determination of trace amount MB. In the paper, the optimum conditions for organic solvent extration, the spectra characteristics of fluorescence and resonance fluorescence were discussed. Besides, the composition and structure of [MeCl4]--MB ionic associates were studied. The fluorescence method could be applied to the determination of MB in urine samples and human serum samples with satisfactory results.
    Study of Bovine Serum Albumin Imprinted Polymer Fabricated with 3-Aminophenylboronic Acid as Functional Monomer on Chitosan Particles
    WANG Hua-Fang1, HE Yun-Hua1, HE Xi-Wen1*, LI Wen-You1, CHEN Lang-Xing1, ZHANG Yu-Kui1,2*
    2008, 29(4):  726-730.  doi:
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    3-Aminophenylboronic acid was used as functional monomer, molecularly imprinted polymer of bovine serum albumin was fabricated on chitosan particles. The Langmuir adsorption model was undertaken to describe the equilibrium isotherms. Analysis of the model shows that many recognition sites of BSA were formed on the MIP with higher adsorption capacity and higher selectivity respect to the other two candidates. Langmuir adsorption equilibrium constant was 49.5 mL/mg and the theoretical maximum adsorption capacity was 16.3 mg/g. The imprinted polymers showed a better selectivity and capacity of the template than one of other competitive proteins. Therefore, this strategy and the functional monomer are promising in molecularly imprinting technology for separating and purifying each protein component in complex bio-samples.
    Natural Compound 20(S)-Protopanaxadiol Activates Cystic Fibrosis Transmembrane Conductance Regulator Chloride Channel
    LIU Jun1,2, NA Wan-Li3, XIN Wei-Hong3, LIU Li-Dan4, YU Bo1, MA Tong-Hui1, YANG Hong1*
    2008, 29(4):  731-735.  doi:
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    In the present study, we identified a natural compound 20(S)-protopanaxadiol as an effective CFTR chloride channel activator by screening of 386 single compounds from Chinese medicinal herbs by cell-based fluorescent assay. The CFTR-stimulating activity was confirmed by an Ussing chamber short-circuit current assay. The activation is rapid, reversible and cAMP-dependent. The compound does not elevate cellular cAMP level, implying that it worked in a direct binding way. 20(S)-Protopanaxadiol can also restore the impaired chloride conductance of ΔF508 mutant CFTR. In our study a new natural compound was identified that may be useful for probing CFTR channel gating mechanisms and as a leading compound to develop pharmacological therapy of CFTR-related disease such as cystic fibrosis, idiopathic chronic pancreatitis, keratoconjunctivitis sicca and habitual constipation.
    研究快报
    Preparation and Application of AlC4Pc-Magnetic Silica Nanotubes
    CHEN Xiao-Lan*, ZOU Jian-Li, LIU Li-Hua, CHEN Xia-Qin, ZHAO Ting-Ting
    2008, 29(4):  736-738.  doi:
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    In this study, we report the preparation and application of the AlC4Pc-magnetic silica nanotubes(AlC4Pc-MSNs), which was synthesized via alumina template membrane method. The synthesized outer-NH2-magnetic silica nanotubes(outer-NH2-MSNs) were characterized by TEM, SEM, EDS and SQUID. Besides these, UV-Vis absorption spectra and fluorescence spectra were also recorded, which further indicate that the AlC4Pc-MSNs have the similar features with free AlC4Pc. The AlC4Pc-MSNs not only have all the advantages of silica nanotubes, but also can be easily separated from the solution by external magnetic field. On the basis of the merits mentioned above, AlC4Pc-MSNs was used for the detection of pH value. Our work herein reveals that the outer-NH2-MSNs will be a promising platform for the applications of the targeting drug delivery, DNA transfection, selective separation, catalyst carriers and so on.
    研究论文
    Synthesis, Characterization and Biological Activity of Ethyl 2-Methyl-1-(4-arylthiazol-2-yl)-benzoimidazole-6-carboxylate
    HU Ai-Xi1*, HE Li-Min1, DONG Min-Yu1, ZHANG Jian-Yu1,2, OU Xiao-Ming2
    2008, 29(4):  739-744.  doi:
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    Compounds containing thiazole or benzoimidazole ring system are found to exhibit a wide spectrum of biological activities. Fourteen new ethyl 2-methyl-1-(4-arylthiazol-2-yl)-benzoimidazole-6-carboxylates were synthesized from ethyl 4-acetamidobenzoate with four steps. Their structures were clearly established by MS, 1H NMR spectra and elemental analysis. The crystal structure of compound 5a was determined by X-ray diffraction analysis. The preliminary bioassays indicate that compound 5c exhibited 95% inhibition rate against E. graminis at 500 mg/L; compound 5e exhibited 61.9% inhibition rate against P. capsici at 25 mg/L. compound 5e exhibited 97.2% inhibition rate against S. sclerotiorum at 500 mg/L, and compound 5k exhibited 55.1% inhibition rate against G. zeae.
    Conformation Analysis on Antibacterial Peptide MDL-1 from Musca domestica Larvae
    GONG Xia1*, LE Guo-Wei2
    2008, 29(4):  745-748.  doi:
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    The structure and conformation of antibacterial peptide MDL-1 from Musca domestica Larvae were studied by infrared spectroscopy(IR),circular dichroism(CD) and fluorescence spectrum methods. Infrared absorption spectroscopy analysis shows that it had the characteristic absorption peak of protein. Amide Ⅰ strip located at 1700—1600 cm-1 in IR spectra. It was found that a trans-configuration in peptide bond was the major characteristic arrangement in the peptide chains, the structure of these peptides were very stable.The secondary structure of antibacterial peptides was determined in different media and under different conditions by CD measurement. A great deal of ordered α-helices and β-sheet, flexible random coil and β-turn conformation were adopted in SDS solution by imitated hydrophobic bacterial membrane means. The fluorescence spectra of MDL-1 excited to exhibit characteristic absorbency of Trp residues and Tyr residuces at 280 nm. We can deduce that the Trp residues of MDL-1 were located in the inner district with negative dielectric instead of the surface. This research provides a foundation for the analysis of antibacterial function.
    Antibacterial Constituents from the Endophytic Fungus Penicillium sp. of Mangrove Plant Cerbera manghas
    HAN Zhuang1,2, MEI Wen-Li2, CUI Hai-Bin1,2, ZENG Yan-Bo2, LIN Hai-Peng2, HONG Kui2, DAI Hao-Fu2*
    2008, 29(4):  749-752.  doi:
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    To study the anti-bacterial constituents from endophytic fungus 093701 of mangrove plant Cerbera manghas, three compounds were isolated by column chromatography from the broth of endophytic fungus Penicillium sp. of Mangrove plant Cerbera manghas, and their structures were elucidated as 4-(3-hydroxybutan-2-yl)-3,6-dimethylbenzene-1,2-diol(1), 4-(3-hydroxybutan-2-yl)-3-acetyl-6-methylbenzene-1,2-diol(2), 3,4,5-trimethyl-1,2-benzenediol(3) by MS, NMR, 1H-1H COSY, HMQC, HMBC etc.. Among them, compounds 1 and 2 were new compounds, compound 3 was a new natural product. Bioassay results showed that compounds 1 and 3 possessed inhibitory effects on MRSA, while compound 2 had no anti-MRSA activity.
    Purification and Properties of Recombinant Ganoderma Lucidum Immunoregulatory Protein
    ZHU Jian-Qiang2, LIANG Chong-Yang1, FENG Kai2, GAI Xiao-Dong2, SUN Xin2, SUN Fei1*
    2008, 29(4):  753-756.  doi:
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    Recombinant Ganoderma lucidum immunoregulatory protein(rGlip) was purified from fermentation. Purification was carried out by ultrafiltration, anion exchange chromatography(AIEC), hydrophobic interaction chromatography(HIC), size exclusion chromatography(SEC). We used Hitrap Q sepharose column to measure the optimal pH value of anion exchange chromatography and detect the absorption value of protein at 215, 254, 280 nm. The intensity absorption of rGlip was found at 215 nm. Hemagglutination reactionno aggregation was observed between any types of human red blood cells, the positive activity was seen in the presence of sheep blood red cells. The optimal pH of AIEC enhanced the yield of initial purification, HIC was designed for lyophobic domains of rGlip, and end product(rGlip) of purification procedures possessed aggregation activity of sheep red blood cells.
    Polypeptide from Chlamys Farreri Inhibits UVA-induced Apoptosis of HaCaT Cells Involving of aSMase-JNK Pathway
    XING Yan-Xia1,2, SU Ai3, DU Wei3, WANG Chun-Bo4*
    2008, 29(4):  757-761.  doi:
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    A pathological model of UVA-induced HaCaT cells was established to investigate whether polypeptide from Chlamys farreri(PCF) protects HaCaT cells from apoptosis induced by UVA through acid sphingomyelinase(aSMase)-JNK pathway and to explore its related molecular mechanism. Apoptosis of cells were determined by Hoechst 33258 staining and agarose gel electrophoresis. The expression of aSMase in HaCaT cells was detected via RT-PCR and immunofluorescence. Using Western Blot analysis, expression levels of JNK and phosphorylated JNK were assayed. The results showed that PCF can significantly protect against UVA-induced apoptosis of HaCaT cells. PCF can also inhibit expression of aSMase and phosphorylated of JNK in HaCaT cells radiated by UVA in a dose-dependent manner. ASMase inhibitor Desipramine and JNK inhibitor SP600125 had inhibitory effects on UVA-induced apoptosis, the former blocked phosphorylated of JNK. So it is concluded that PCF can protect HaCaT cells from apoptosis induced by UVA and its protective effects may attribute to blocking aSMase-JNK pathway.
    Purication and Heat-stable Properties of a Novel Protease from Pseudomonads fluorescens Rm12
    MU Zhi-Shen1,2, Bai Ying2, ZHAO Guang-Hua1, HU Xiao-Song1*
    2008, 29(4):  762-766.  doi:
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    Heat-resistant proteases from psychrotrophic bacteria in raw milk may induce bitterness, gelation and hydrolyzation of sterilized milk. A novel extracellular heat-stable metalloprotease, named as Ht12, was found for the first time from Pseudomonads fluorescens Rm12,which was isolated from raw milk. Ht12 was purified to homogeneity from the culture supernatant via ammonium sulfate precipitation, ion-exchange chromatography, hydrophobic chromatography, and size exclusion chromatography and its properties of enzymology and heat-stable properties was studied. This protease in its native state was identified as a monomer of 45000 Da, containing Pro and disulfide bonds and the N-terminal sequence was MSKVKDKAIVSAAQAS. Mn2+ has positive effect on activity. The protease has a higher heat resistance. After treatment of 160 ℃ for 20 s, the residual activity was 3.8%.
    New Binuclear Allylating Reagents for Allylation of Aromatic Aldehydes
    WEI Xiao-Ning, LIU Ling-Yan, YU Lei, CHANG Wei-Xing, LI Jing*
    2008, 29(4):  767-771.  doi:
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    A new and simple methodology was reported for the allylation of aromatic aldehydes. In this protocol, new type of binuclear allylmetal reagents(with Sn—Mn, M=Mn or Fe) reacted with aldehydes in dichloromethane, without any other additives, to form homoallylic alcohols with yields from moderate to higher yields(42%—98%). Ample examples showed us that Tin-promoted carbonyl allylation is normally effected by either Sn(CH2CHCH2)4 or Bu3Sn(CH2CHCH2). In our work, we had synthesized three new binuclear compounds, a novel type of allylating reagent containing Sn—M bond(M=Mn or Fe). And it was found that they could also be applied in the allylation of aldehydes. This system owns the virtues of operational simplicity and more moderate condition. The allyl group in these binuclear compounds has been proved to be more reactive by the co-mediation of the transition metal groups and the bond formation of the M—Sn.
    研究快报
    Esterification of Aromatic Acids and Alcohols in Acidic PEG Thermoregulated Ionic Liquid
    ZHI Hui-Zhen, LUO Jun, MA Wei, LÜ Chun-Xu*
    2008, 29(4):  772-774.  doi:
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    Two Acid sites PEG thermoregulated ionic liquid was prepared and used as the catalyst for the esterification of aromatic acid and alcohol. The yield of esterification catalyzed by ionic liquid was 99% in 1 h at 80 ℃ with 0.1%(molar fraction) acidic PEG ionic liquid. The catalyst system could be applied to a wide range of esterification of aromatic acids and alcohols. The ionic liquid has the advantages of both homogeneous and heterogeneous phase at different temperature with a high product yield and the ease of product as well as catalyst separation. The ionic liquid studied plays the role of catalyst and is recycled up to seven times without any significant loss of activity. Morover, by simple phase separation the ionic liquid phase could be re-utilized up to seven times without leaching.
    研究论文
    Relationship Between the Adsorption Capacity of Hydrogen Isotopes and Specific Surface Area of Adsorbents
    CHU Xiao-Zhong*, XU Ji-Ming
    2008, 29(4):  775-778.  doi:
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    The equilibrium adsorption capacity of hydrogen and deuterium on different micro- and mesoporous molecular sieve adsorbents and the specific surface area were measured at 77 K with a volumetric method. The results indicate that a good linear relationship was observed between the adsorption capacity of hydrogen isotopes and the specific surface area for the same kind of adsorbents, which provided a convincing proof of the monolayer adsorption mechanism for hydrogen isotopes at supercritical temperature. The adsorption capacity on microporous molecular sieves was larger than that on mesoporous molecular sieves at the same temperature, pressure and specific surface area, which was attributed to the overlapping of adsorption potential in micropores of adsorbents. An adsorption potential model was proposed that could be used to explain this experimental results well.
    Synthesis and Properties of a Novel Charge Trasfer Type of Molecule FcBAK/Molybdophosphoric Acid Composite
    WU Ying1*, LI Zheng1, JU Jin-Mei2, WEN Di-Jiang2
    2008, 29(4):  779-782.  doi:
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    A novel organic-inorganic molecule with a composition of [Fe(C5H5)2COC2H2C6H5]3HPMo12O40·2H2O was synthesized by solid-state reaction at room temperature. The compound was characterized via elemental analysis, IR, ICP, AAS, TG. The results of solid electronic absorption spectra and ESR spectra show that charge transfer between Fe(C5H5)2COC2H2C6H5(1-ferrocenyl-3-benzoyl-2-alkene-1-ketone, short of FcBAK) and polyoxometalate anion(molybdophosphoric) took place and the polyoxometalate anion formed a mixed valence compound. Magnetic measurement result shows that the compound is a ferromagnetic materials, with its Ms=0.41 A·m2/kg, Hc=0.0105 T. The relationship between the structure and magnetic propety has been discussed. This work provides a way for design and synthesis of novel organic-inorganic magnetic materials.
    Potential and Current Oscillations During Electrocatalytic Oxidation of Formaldehyde at a Pt Nanoparticles Modified Electrode
    TANG Yi-Ting, ZHAO Guo-Hua*, CHEN Rui, GENG Rong, HU Hui-Kang
    2008, 29(4):  783-787.  doi:
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    The platinum(Pt) nanoparticles modified titanium electrode was prepared via the method of cathodic reduction followed by anodic oxidation. Scanning electron microscopy(SEM) analysis illustrated that Pt nanoparticles were dispersed highly in the three-dimensional pore network of titanium oxide on the surface of this electrode. Not only potential oscillations under galvanostatic conditions but also current oscillations under both cyclic voltammetric and potentiostatic conditions during the formaldehyde(HCHO) oxidation were observed with several different electrochemical methods. This further revealed that the highly-dispersed Pt nanoparticles improved greatly the electrocatalytic activities of electrode, then facilitated the oxidation process of HCHO and its intermediate product so that these were favorable to the production of electrochemical oscillations. Also, many factors such as the concentration of HCHO and H2SO4, the applied potential or current were shown to have regular influence on the intensity, region or pattern of oscillations.
    Preparation and Photoelectrochemical Properties of ZnSe Nanorods and Spherical ZnSe Particles
    HAO Yan-Zhong1,2*, FENG Yun2
    2008, 29(4):  788-792.  doi:
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    ZnSe nanorods and ZnSe spheres were prepared with hydrothermal method, the products were characterized with XRD, TGA-DTA, SEM, the possible formation mechanism involving a co-growth process is proposed. The results show that the nanorod was formed approximately with the diameter of 50—100 nm and the length of 200—300 nm, the diameters of the spherical ZnSe ranged from 3 to 10 μm. The mixture of zinc blende and wultize structures of ZnSe nanorods could be obtained at reaction temperature of 240 ℃ and the zinc blende structure of ZnSe spheres could be obtained at reaction temperature of 210 ℃; The ZnSe nanorods/ITO film and spheres/ITO were sintered at 380 ℃ for 40 min. Photoelectrochemical properties of ZnSe nanorods and ZnSe spheres were studied. The maximum IPCE of ZnSe nanorods measured was 9.09%.
    Acidizing Reaction in Microtubes: Deposition and Interface Effects
    ZHAO Ren-Bao*, YUE Xiang-An, WU Ya-Hong, HOU Ji-Rui
    2008, 29(4):  793-798.  doi:
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    The micro-scale flow behavior in glass microtubes has aroused the interest of a wide variety of researchers in recent years. The glass microtubes with different inner diameters were used in this paper to simulate the porous oil reservoir, and the experiments conducted on the chemical reactions between microemulsified acid and mud acid within these microtubes. Microscope observation results show that the reaction velocity of mud acid in microtube is larger than that of microemulsified acid. Deposition produced after the mud acid entered the microtube and reacted for a period of time, while only corrosive spot appeared during the microemulsified acid reaction in it. The less the inner microtube diameter, the more ready the coalescence of bubble produced to happen and form gas-liquid annular distribution. The mud acid reaction rate, which was various at different positions in the micro tube, reaches the maximum at the position of gas-liquid interface and declines with the increase of the distance from the interface. The flow rate in a microtube(ID=50 and 25 μm), which indicates its flow ability(permeability), increases to different degrees after it reacts with both the acid solution(reaction time 24 h). And the rate increase is more obvious in the microtube after acid-etched by microemulsified acid than mud acid. These experiments not only show secondary precipitation as mud acid reacting with sand reservoir, but also interfacial effect during the reaction process. Microemulsified acid is an optimum acidizing fluid for it can eliminate pecipitation and interficial effect during the process of acid-etching.
    Low-temperature Heat Capacities and Thermochemistry of Sodium Nicotinate Na(C6H4NO2)(s)
    YANG Wei-Wei1, KONG Yu-Xia1, DI You-Ying1*, SHI Quan2, TAN Zhi-Cheng2
    2008, 29(4):  799-804.  doi:
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    Nicotinic acid and sodium acetate were chosen as the reactants, a compoundsodium nicotinate was synthesized by the method of room temperature solid phase synthesis. FTIR and X-ray powder diffraction technique were applied to characterize its structure, and its composition was determined to be Na(C6H4NO2) by chemical and elemental analyses. Low-temperature heat capacities of the compound were measured by a precision automated adiabatic calorimeter over the temperature range from 78 K to 400 K. A polynomial equation of the heat capacities as a function of the temperature was fitted by the least square method. On the basis of the fitted polynomial, the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated at the interval of 5 K. A reasonable thermochemical cycle was designed on the basis of the solid phase preparation reaction of the substance, 1 mol/L NaOH solution was chosen as the calorimetric solvent, and the standard molar enthalpies of dissolution for the reactants and products of the solid phase reaction in the selected solvents were measured by an isoperibol solution-reaction calorimeter, respectively. In addition, the enthalpy change of the solid phase reaction was determined to be (23.232±0.509) kJ/mol from the data of the above standard molar enthalpies of dissolution. Eventually, the standard molar enthalpy of formation of sodium nicotinate was derived to be: ΔfHm0[Na(C6H4NO2), s]=(-548.96±1.11) kJ/mol, by the combination of the enthalpy change of the solid phase reaction with other auxiliary thermodynamic quantities.
    New Theoretical Method for Studying Polycondensation of Aa Type

    ZHAO Zuo-Fei1, WANG Hai-Jun1,2*

    2008, 29(4):  805-808.  doi:
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    The canonical partition functions of polycondensation of Aa type were constructed from two viewpoints by the principle of statistical mechanics, and the explicit expressions of the equilibrium free energy and the law of mass action were obtained. Meanwhile, two new methods were used to derive the number fraction distribution function. Below the critical point of the sol-gel transition, the equilibrium free energy of sol and gel phases were given on the basis of the intrinsic invariant property of the number faction distribution function. Furthermore, the sol-gel phase transition is shown to be a kind of geometric phase transition rather than thermodynamic phase transition.
    Theoretical Study of the Reaction of NCO Radical with O, N atoms
    ZHAO Xiao-Lei, JI Yue-Meng, LIU Jing-Yao, LI Ze-Sheng*
    2008, 29(4):  809-811.  doi:
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    The potential energy surface of radical-radical reactions between NCO and O, N were investigated theoretically with the density function theory and ab inito method at CCSD(T)/6-311G(d)//B3LYP/6-311G(d) level. The main reaction paths were discussed. The mechanisms of the two reactions are similar, and both have two initial association ways. For the reaction NCO+O, the reaction path through which O atom was initially associated with N atom of NCO and then the adduct passed a low barrier to yield product P1(CO+NO) is the most favorable path. For the reaction NCO+N, one reaction path was found and the initial intermediate complex was obtained by a barrierless process for N—N association.
    Theoretical Studies on the CH3CH2S Radical Hydrogen Shift Isomerization and Dissociation Reaction
    SHI Zhao-Hui1, WANG Wen-Liang1*, WANG Wei-Na1, LI Chun-Ying2, LÜ Jian2
    2008, 29(4):  812-818.  doi:
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    Density functional theory B3LYP/6-311+G(d,p) method was employed to reveal the micro-kine-tic character of the hydrogen shift isomerization and dissociation reaction of the CH3CH2S. In order to obtain more reliable energies, the single point calculations were carried out at the QCISD(T)/6-311++G(d,p) level of theory. The rate constants of the reactions were evaluated by means of the canonical variational transition-state theory(CVT) conjunction with small- curvature tunneling(SCT) correction over a wide range of temperature 200—2000 K at the QCISD(T)/6-311++G(d,p)//B3LYP/6-311+G(d,p) level. In this study, the potential barriers ΔE≠ of the 1,2-H shift, 1,3-H shift, C—C dissociation and β-C—H dissociation reactions of the CH3CH2S radical are 149.74, 144.34, 168.79 and 198.29 kJ/mol, respectively. The 1,2-H shift is the major reaction process when temperature is lower than 800 K, and C—C dissociation reaction became the dominant when temperature is higher than 1800 K, and 1,3-H shift is the major pathway when temperature is between 1300 and 1800 K. The β-C—H dissociaton reacton always play a minor role over the whole temperature region.
    Molecular Dynamics Study of Transcriptional Activation Mechanism of Heme Activator Protein
    ZHAO Xi, HUANG Xu-Ri*, SUN Chia-Chung
    2008, 29(4):  819-823.  doi:
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    A molecular dynamics(MD) simulations for three kinds of protein(heme activator protein: HAP)-DNA complexes crystal structures were performed: the HAP1-wt, two HAP1 mutants(HAP1-PC7: Ser63/Gly63; HAP1-18: Ser63/Arg63) with the aim of investigating the mechanism of HAP transcriptional activation. Comparative analyses of MD structures for the three HAP-DNA complexes reveal that the key protein-DNA interactions involving the recognization of UAS i.e CGC are different in three complexes as the experimental observations. Further analyses reveal that three HAPs exhibit different flexibilities, relative to very similar conformations of three bound DNA. It is found that the difference of flexibilities in three HAPs results in diversities in conformations of N-term Arm and Zn2Cys6 Binuclear Cluster involving DNA recognition, causing varieties of protein-DNA interactions. According to these results, the flexibility of N-term and Zn2Cys6 Binuclear Cluster in HAP can play a crucial role in regulating transcriptional activation, which can directly lead to the alternative protein-DNA interactions.
    Theoretical Study on the Surface Energy of TiO2 Rutile(110)
    WEI Zhi-Gang1,2, ZHANG Hong-Xing1*, LI Qian-Shu2, LEWIS James P.3
    2008, 29(4):  824-826.  doi:
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    The density functional theory and pseudopotential method were employed to investigate the TiO2 rutile(110) surface energy corresponding to the defect concentration. It is shown that the surface energy is dependent on the defect percentage, i.e., the zero defect surface possesses the lowest surface energy and the 100.0% defect surface possesses the highest surface energy. On the other hand, when we added O atoms to the fivefold-coordinate Ti4+ sites of the perfect surface with a defect below 50%, there is little change of the surface energy, although the perfect surface still has the lowest surface energy. When we added more O atoms to these sites, the surface energy becomes higher.
    Synthesis and Properties of Copolymers Based on Dialkylfluorene and 3,6-Fluorene Substituted by Triphenylamine Units
    WU Zhong-Lian, WANG Lei, LIU Jin-Cheng, YING Lei, YANG Wei, CAO Yong*
    2008, 29(4):  827-831.  doi:
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    A series of conjugated copolymers derived from 9,9-dioctyl-2,7-fluorene(DOF) and 9,9-bis(4-diphenylaminophenyl)-3,6-fluorene(36FT) were prepared by Suzuki coupling polymerization, which have a high molecular weights(Mn=47000—189000). The resulting copolymers are readily soluble in common organic solvents such as THF, CHCl3 and toluene etc.. The electrochemical, optical and electroluminescent properties were investigated. Cyclic voltammogram(CV) indicates that the HOMO level of the copolymers is higher than that of the PF homopolymer, and it increases with the increase in 36FT mass fraction from 2% to 35%. The blue polymer light-emitting diodes(PLEDs) with the device configuration of ITO/PEDOT/PVK/polymer/Ba/Al were prepared. The highest external quantum efficiency was 0.52% from the device with 36PFT10 as the active layer.
    Effect of Interaction Between Gel and Substrate on the Frictional Behavior of Poly(vinyl alcohol) Hydro-gel
    DU Miao*, HU Xin-Liang, ZHENG Qiang
    2008, 29(4):  832-836.  doi:
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    The friction behavior of polyvinyl alcohol(PVA) gel sliding against different substrate surface, i.e. glass plate and Aluminiumin(Al) plate in water was investigaed. The results reveal that the frictional stress(f) for Gel-Al system is higher than that of Gel-glass owing to the strong interaction between PVA gel and Al plate. At the same time, the elastic-hydrodynamic transition velocity(vf) for Gel-Al system is higher than that of Gel-glass system, which also supports the theoretical prediction. In slow sliding velocity region, the interaction between PVA gel and substrate seems no influence on the sensitivity of f to normal pressure. The vf for a system with weak interaction between gel and substrate, such as Gel-glass, will increase with the increase of normal pressure. However, vf for a system with strong interaction between gel and substrate, such as Gel-Al, seems insensitive to normal pressure. In the fast sliding velocity region, the liquid lubrication prevails and f∝(ηvP)1/2.
    Preparation and Evaluation of the Biotinylated Polymer Coating
    LU Tian-Cheng1,2, DENG Chao1,2, SUN Jing1,2, CHEN Xue-Si1, ZHANG Pei-Biao1, JING Xia-Bin1*
    2008, 29(4):  837-841.  doi:
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    A novel bioactive polymer coating without nonspecific adsorption of proteins was prepared from a biodegradable amphiphilic triblock copolymer, biotinylated poly(ethylene glycol)-b-poly(L-lactide)-b-poly(L-lysine)(PEG-PLA-PLL/biotin) by coating it on a substrate and covering it with a layer of blocking coating consisting of gelatin and poly(N-vinyl pyrrolidone). The bioactive surface was characterized by enzyme linked immunoassay, on the basis of sequential immobilizations of horseradish peroxidase labeled streptavidin, biotinylated mouse globulin, and alkaline phosphatase labeled horse anti mouse IgG(H+L). The results showed that the bioactive surface was resistant to nonspecific protein adsorption but allowed specific recognition and combination between biotin and streptavidin, and meanwhile, the combined streptavidin retained its bioactivity. Therefore, subsequent protein immobilization can be realized via the reaction of the streptavidin and biotinylated proteins.
    Effect of Shear on the Crystallization Behavior of Glass Bead Filled Polypropylene
    ZHAO Gui-Yan1,2, WANG Ying1,2, MEN Yong-Feng1, JIANG Wei1*
    2008, 29(4):  842-846.  doi:
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    Linkam CSS450 optical shearing stage, wide-angle X-ray diffraction(WAXD) and small-angle X-ray scattering(SAXS) were used to investigate the effect of shear on crystal structure and crystallization morphology of the glass bead filled polypropylene(PP). The results indicate that the glass bead worked as nucleating agent for the glass bead filled PP, compared with pure PP it restrained the formation of β-crystal after shear treatment. When the mean size of glass bead is smaller(4 μm) shear rate had less effect on the formation of β-crystal of PP obviously. However, when the mean size of glass bead is larger(35 μm), it was found that 20 s-1 is an optimal shear rate for the formation of β-crystal. Both shear and glass bead addition could induce the orientation of the lamella of the glass bead filled PP. The higher the shear rate and the bigger the glass bead, the higher the orientation of the lamella was.
    Morphological Structure of Melt-drawn Films of Polyethylene Containing Small Amount of Copolymerized Component
    TONG Cui-Yan1,2, CHEN Yong2, CHEN Ye2, YANG De-Cai2*, ZHANG Jing-Ping1*
    2008, 29(4):  847-850.  doi:
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    The morphological structures of melt-drawn films of polyethylene containing small amount of copo-lymerized component[0.64%(molar fraction) of butylene-1] were studied by TEM and DSC techniques. The results indicate that, in addition to highly oriented lamellae, the melt-drawn films of the polyethylene copolymer contain large amount of fibrous crystals with average diameter about 12 nm, which are parallel to drawing direction. Simulation experiment[adding 1%(mass fraction) ultra-high molecular weight polyethylene(UHMWPE) into regular high density polyethylene] proves that the formation of the fibrous crystals originates from ultra-high molecular weight component in the polyethylene copolymer. However, this kind of fibrous crystal is different from classical extended chain fibrous crystal. Morphological characteristics of the fibrous crystal of the copolymer should be crystal-bridged structure with an alternating alignment of crystalline and noncrystalline regions. A model of crystal-bridged fibrous crystal was proposed, which not only benefits understanding the mechanism of the oriented crystallization of polymers, but also provides a theory foundation for improving the properties of the material.
    Properties and in vitro Evaluation of Chitosan-NAC Nanoparticle for Drug Release
    WANG Xin1, WU Zhong-Ming2, ZHANG Xin-Ge1, ZHENG Chao1, WANG Zhen1, LI Chao-Xing1*
    2008, 29(4):  851-857.  doi:
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    Nanoparticles have received much attention in the development of transmucosal administration because of the special nano-effectivity. On the basis of the formation of disulphide bonds between thiol groups on polymer and cysteine-rich domains of mucus glycoproteins, the thiolated nanoparticles as carriers can prolong the residence time of drugs on the nasal mucosa and allow a sustained drug release at a given target site. In this study, a novel nanoparticle containing N-acetyl-L-cysteine-g-chitosan conjugate(CS-NAC) was prepared and characterized. Mucoadhesive and swelling properties of CS-NAC conjugates were evaluated in vitro. Release studies were performed with insulin as the model drug. The resulting insulin-loaded CS-NAC nanopartilces had a diameter of 140—210 nm, positive zeta potential values(19.5—31.7 mV) and insulin loading(13%—42%). The physicochemical properties of nanoparticles were affected by the amount of thiol groups. The thiolated chitosan nanoparticles exhibited much higher and faster mucoadhesion than unmodified chitosan nanoparticles. In vitro release studies demonstrate that the insulin-loaded CS-NAC nanopartilces was pH-sensitive delivery systems. At pH=6.8, 58.6% of insulin was released from CS-NAC4 nanoparticles within 15 min, while less than 40% of insulin was release with 24 h at pH=5.4. Therefore, the novel thiolated chitosan nanoparticle appears to be a very promising vehicle for transmucosal insulin drug delivery.
    Preparation and Characterization of Novel Magnetic Cationic Polymeric Liposomes
    LIANG Xiao-Fei, WANG Han-Jie, TIAN Hui, LUO Hao, CHENG Jing, HAO Li-Juan, CHANG Jin*
    2008, 29(4):  858-861.  doi:
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    Octadecyl quaternized carboxymethyl chitosan(QACMC) was synthesized through carboxymethyl chitosan grafting with glycidyl octadecyl dimethylammonium chloride. Then, novel magnetic cationic polymeric liposomes(MCPL) formed from QACMC/cholesterol and Fe3O4 ferrofluid were prepared via Thin-Layer Evaporation. The structure and properties of all samples were characterized via TEM, DLS, VSM and FTIR. The results show that the superparamagnetic cationic polymeric liposomes were prepared successfully. It was stable in aqueous phase and had a high zeta potential of +38.22 mV. The average diameter of MCPL was about 15 nm and the saturation magnetization value of it was 28 A·m2/kg at 300 K. Vincristine as a kind of hydrophilic components was entrapped into its aqueous core. Vincristine encapsulation efficiency of MCPL was 93.1% and it exhibited a slow steady release of vincristine over two weeks at 37 ℃ in Tris-HCl(pH=7.4).
    研究快报
    Electrostatic-assembly Behavior Between Cationically Modified Silica and End-functionalized Polystyrene
    SHI Bo1, ZHANG Yong-Hua1*, SHI Yao-Gang2, WANG Jian-Hua2
    2008, 29(4):  862-864.  doi:
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    Polystyrene brushes were constructed on cationically modified silica nanoparticles(SiO2-CBAFS) by electrostatic-assembly. TGA, TEM, AFM and contact angle were used to characterize the mass loss, microscopic images, topology, surface property of the products, respectively. The results show that PS-NH-SO3Na can be successfully attached to the surface of SiO2-CBAFS nanoparticles by electrostatic-assembly with high grafting density, which is much higher than that from the reports; the aggregation of silica can be prevented efficiently by being assembled a monolayer of PS-NH-SO3Na; the water contact angles of the Si/SiO2-CBAFS/PS-NH-SO3Na decrease with the increase of molecular weight and the mass concentration of PS-NH-SO3Na under different environments.
    Synthesis, Characterization and Properties of Novel Soluble Poly(ether ether ketone) Containing Fluorin Structure
    ZHANG Peng, LIU Xin-Cai, LI Peng, ZHOU Hong-Wei, CHEN Chun-Hai*
    2008, 29(4):  865-867.  doi:
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    The novel and soluble poly(ether ether ketone)(PEEK) containing fluorin structure(6F-PEEK) was prepared by nucleophilic reaction of 4,4’-difluorobenzophenone, bisphenol A and hexafluobisphenol A in the presence of anhydrous K2CO3 with tetramethylene sulfone as the solvents. The molecular weight of the polymer was determined by GPC. The structure of the polymer was characterized by FTIR, 1H NMR and 19F NMR spectroscopies. The glass transition temperature and the temperature for 5% mass loss of 6F-PEEK were 153 and 493 ℃, respectively. The polymer exhibits an excellent thermal stability, mechanical property and solubility. The rate of elongation at break, tensile strength and tensile modulus of 6F-PEEK were 55.2%, 66 MPa, and 2.13 GPa, respectively.
    Synthesis of AM/AMPS/N8AM Tercopolymer in Ionic Liquids and Performance of the Polymer Solution
    DING Wei1*, LIU Hai-Yan1,2, YU Tao1, QU Guang-Miao1
    2008, 29(4):  868-870.  doi:
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    The tercopolymer AM-AMPS-N8AM was prepared through radical polymerization with 1-butyl-3-methyl imidazolium tetrafluoroborate ionic liquids as the reaction medium of polymerization, benzoperoxide/N,N-dimethylaniline(BPO/DMA) redox system as the initiator, acrylamide(AM) and 2-acrylamido-2-methylpropane sulfonic acid(AMPS) as the hydrophilic monomer, N-octylacrylamide(N8AM) as the hydraphobic monomer. The structure of polymer was identified by 1H NMR, 13C NMR and element analysis. The apparent viscosity of the terpolymer aqueous solution is measured, and the result shows that the terpolymer synthesized in ionic liquids has an excellent tackifying ability.When the mass concentration of solution is 1.2 g/L, the apparent viscosity can reach 220.1 mPa·s, when the temperature changes from 45 ℃ to 90 ℃, the viscosity remaining rate is 65% and when the shear rate increases to 24.48 s-1, the viscosity remaining rate is 43.5%. It is shown that the tercopolymer solution has better temperature tolerance and shearing resistance
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