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Table of Content

    24 April 2004, Volume 20 Issue 2
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    Articles
    A Novel Hydrogen-bonded Three-dimensional Network Complex Containing Nickel
    WANG Li, LI Juan, WANG En-bo
    2004, 20(2):  127-130. 
    Abstract ( )   PDF (217KB) ( )  
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    A novel complex, (H3O)2[Ni(2,6-pydc)2]·2H2O was synthesized in an aqueous solution and characterized by means of single-crystal X-ray diffraction, elemental analyses and IR spectra. The X-ray structural analysis revealed that the novel compound forms three-dimensional(3D) networks by both π-π stacking and hydrogen-bonding interactions. The crystal data for the complex are a = 13. 853 (3) nm, b= 9. 6892 (19) nm,c=13.732(3) nm, α=90. 00°, β=115.52(3)°, γ=90.00°, Z=3, R1=0.0786, wR2=0.1522.
    Synthesis and Characterization of AlPO4-11 and MAPO-11 Single Crystals
    LI Jian-jun, LI Guo-dong, XI Chun-yu, GUO Ying, CHEN Jie-sheng
    2004, 20(2):  131-133. 
    Abstract ( )   PDF (186KB) ( )  
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    The preparation of two types of molecular sieves AlPO4-11 and MAPO-11 is reported. The particle size of the latter is hundreds of microns, about 10 times larger than that of the former. The XRD, IR and DTA spectra have demonstrated that magnesium has been introduced into the framework of AlPO4-11. The successful preparation of large single crystal of MAPO-11 will open up a new area for the preparation of large molecular sieves crystals in the future. The large MAPO-11 crystal compound is a promising host for the host-guest assembly of composite materials.
    Subtracting Technique of Baselines for Capillary Electrophoresis Signals
    WANG Ying, MO Jin-yuan, CHEN Zuan-guang, GAO Yan
    2004, 20(2):  134-137. 
    Abstract ( )   PDF (215KB) ( )  
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    The drifting baselines of capillary electrophoresis affect the veracity of analysis greatly. This paper presents Threshold Fitting Technique(TFT) so as to subtract the baselines from the original signals and emendate the signals. In TFT, wav elet and curve fitting technique are applied synthetically, thresholds are decided by the computer automatically. Many experiments of signal processing indicate that TFT is simple for being used, there are few man-induced factors, and the results are satisfactory. TFT can be applied for noisy signals without any pre-processing.
    Enhancement of Raman Scattering of 1,4-Benzenedithiol by CdS Nanoparticles Assembled on a Silver Surface
    ZHOU Qun, ZHAO Hong, LI Xiao-wei, ZHENG Jun-wei
    2004, 20(2):  138-141. 
    Abstract ( )   PDF (203KB) ( )  
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    CdS nanoparticles were assembled on the smooth surface of a piece of silver by using 1,4-benzenedithiol as coupling molecules. The SEM and resonance Raman spectroscopic characterizations demonstrate that the nanosized structure of CdS was still preserved upon assembly, and a two-dimensional structure of CdS nanoparticles was formed on the substrate surface. The FT-Raman spectra indicate that 1,4-benzenedithiol was coupled between CdS nanoparticles and the silver surface with a tilted orientation. The Raman scattering of 1,4-benzenedithiol was substantially enhanced by the assembled CdS nanoparticles, probably due to the alteration of the polarizability of 1,4-benzenedithiol and the electromagnetic interaction between the dipoles of the CdS particle with its image in the metal substrate.
    Synthesis of γ-Substituted Alcohol with Polymer-bound Amide
    REN Jun, HUANG Jin-xia, LI Yan, ZHOU Yuan-yuan
    2004, 20(2):  142-145. 
    Abstract ( )   PDF (210KB) ( )  
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    With solid phase organic synthesis method(SPOS), polymer-bound N-enoylprolinol(4) was prepared by the attachment of N-enoylprolinol(3) to Merrifield resin and was used for asymmetric Michael additions for the first time. The enantiomeric excess obtained by this method is increased as compared with that obtained by the corresponding solution phase reactions.
    Crystal Structure of Bis (O,O'-diisopropyl dithiophosphate):[(C3H7O)2PS2]2
    ZHANG Shu-sheng, LI Xue-mei, WANG Jin-li, WAN Jun, JIAO Kui
    2004, 20(2):  146-148. 
    Abstract ( )   PDF (173KB) ( )  
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    The crystal and molecular structures of [(C3H7O)2PS2]2 (CCDC No.217201) were determined by means of X-ray crystallography. It crystallized in a triclinic system with space group P-1 and lattice parameters a=0.82794(3) nm, b=0.84764(2) nm, c=0.85034(3) nm, α=97.78(3)°, β=110.77(3)°, γ= 94. 95 (3)°,V= 0. 54701(9) nm3, Z= 1. In this molecule, the two diisopropyl dithiophosphate groups, [(C3H7O)2PS2]2,which are parallel to each other, are linked by an S-S bond and there exist inversion centers in the molecule.In the structure, the P＝S bonds in the two dithiophosphate units are trans-oriented to each other.
    Syntheses of Novel 5-Alkylamido-1,10-phenanthrolines
    SHU Huo-ming, LI Hua-ming, HAN Chang-ri, WANG Peng
    2004, 20(2):  149-151. 
    Abstract ( )   PDF (158KB) ( )  
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    5-Amino-1, 10-phenanthroline and three types of new 5-substituted 1,10-phenanthroline derivatives by different alkyl amides, phen-NHCOR [phen = 1,10-phenanthroline;R＝CH＝CH2;(CH2)nBr, n = 1,3-5;(CH2)nCH3, n = 9-14], were synthesized. They were characterized by means of elemental analyses, infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and mass spectroscopy. These new compounds are important ligands or the active materials of ruthenium (I) electrochemiluminescent (ECL) sensors.
    Two-stage pH Control Mode in Batch Fermentation of a Novel Bioflocculant from Corynebacterium Glutamicum
    HE Ning, WU Xiao-jie, DENG Xu, LU Ying-hua, LI Qing-biao
    2004, 20(2):  152-155. 
    Abstract ( )   PDF (592KB) ( )  
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    The effect of pH of the fermentation medium on cell growth and the production of a novel bioflocculant (named REA-11 ) by Corynebacterium glutamicum CCTCC M201005 were investigated. The maximum biomass (2.23 g/L) and flocculating activity (142.2 U/mL) were simultaneously obtained at the 14th hour when the pH value of the culture medium was maintained at 7.0 during the whole fermentation process. The production of REA-11 kept on a trend of increase till the later phase of fermentation process, which resulted in the ultimate flocculating activity of the culture broth to enhance to nearly 100 U/mL at pH 6.0. A twostage pH control mode was adopted in REA-11 production in which the pH value of the culture medium was controlled at 7.0 during the first 14 h, then decreased to 6.0 that was maintained until the end of the fermentation process. With the two-stage pH control mode, the maximum flocculating activity reached 178.8 U/mL which was 30% higher than that obtained under the condition of pH 7.0 and the biomass enhanced about 15%. Compared with the fermentation process without pH control, REA-11 production and cell growth via the two-stage pH control mode increased 80% and 25%, respectively.
    Chitosan Obtained from Cell Wall of Aspergillus Niger Mycelium
    HUANG Hui-li, LIN Wen-luan, LIN Jian-ming
    2004, 20(2):  156-158. 
    Abstract ( )   PDF (163KB) ( )  
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    Chitin from cell walls of Aspergillus Niger mycelium was prepared. A new method for the preparation of high deacetylation degree chitosan was studied in a dilute sodium hydroxide solution at a high pressure. The experimental results indicate that the deacetylation degree of the chitosan can reach 80% under the condition of a 5.00 mol/L sodium hydroxide solution at 0.1 MPa of pressure for 1 h. This method shows the advantages of the applications in the industry production and environment protection.
    Application of Waste Liquids Containing Lignin from Pulp-producing Industry to CWM Preparation
    HUANG Ding-guo, TADAHIRO Murakata, TAKESHI Higuchi, SHIMIO Sato
    2004, 20(2):  159-162. 
    Abstract ( )   PDF (217KB) ( )  
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    Three kinds of craft waste liquids, which are by-products in the pulp industry and contain much lignin,were used as dispersing additives for preparing Horonai coal CWM (coal water mixture). The experiments showed that the CWM exhibited the lowest viscosity when it was diluted with an appropriate amount of water with the waste eiquids added. The experim ents also indicated that the maximum coal concentr ation in the pr act ically applicable CWMs w hose appar ent v iscosity has to be below 1000 m Pa·s incr eased fro m 56.5% to 62.5% (mass fraction), and 56.5% is the maximum coal mass fraction of the CWM prepared without additives. These data show the effectiveness of the waste liquids as the additives for preparing CWMs. The zeta potential of coal particles in the CWMs changed with the addition of lignin. From the change, the steric repulsion effect of the lignin adsorbed on the coal particles is concluded to be mainly responsible for the CWM dispersion. The waste liquids contain less sulfur than PSSNa(polystyrene sulfonate sodium salt), a typical dispersant which is currently used for preparing the commercial CWM, when the sulfur content in the unit mass of the solid matters within the waste liquids is compared with that in unit mass of PSSNa. This fact suggests that the waste liquids are more advantageous than PSSNa as far as air pollutants are concerned.
    Estimation of Critical Rate of Temperature Rise for Thermal Explosion of First Order Autocatalytic Decomposition Reaction Systems by Using Non-isothermal DSC
    GUO Peng-jiang, HU Rong-zu, ZHANG Hai, XIA Zhi-ming, SONG Ji-rong, GAO Sheng-li, NING Bin-ke, SHI Qi-zhen, LIU Rong, LU Gui-e, JIANG Ji-you
    2004, 20(2):  163-165. 
    Abstract ( )   PDF (176KB) ( )  
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    A method of estimating the critical rate of temperature rise for the thermal explosion of first order autocatalytic decomposition reaction systems by using non-isothermal DSC is presented. The information was obtained on the increasing rate of temperature for the first order autocatalytic decomposition of nitrocellulose containing 13.86% nitrogen converting into the thermal explosion.
    Application of Angular Momentum Theory to Constructing Basis Functions of Irreducible Representations of Icosahedral Group
    LI An-yong
    2004, 20(2):  166-175. 
    Abstract ( )   PDF (477KB) ( )  
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    A new method based on angular momentum theory was proposed to construct the basis functions of the irreducible representations(IRs) of point groups. The transformation coefficients, i. e. , coefficients S, are the components of the eigenvectors of some Hermitian matrices, and can be made as real numbers for all pure rotation point groups. The general formula for coefficient S was deduced, and applied to constructing the basis functions of single-valued irreducible representations of icosahedral group from the spherical harmonics with angular momentum j≤7.
    Hydrogenation of Toluidines Catalyzed by Silica-supported Carboxymethylcellulose-platinum Complex
    WANG Xin, YANG Ji-huo, HUANG Mei-yu, JIANG Ying-yan
    2004, 20(2):  176-179. 
    Abstract ( )   PDF (2051KB) ( )  
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    The hydrogenation of toluidines catalyzed by silica-supported carboxymethyl cellulose platinum complex forms methylcyclohexlamines in high yields, such as m-toluidine to 3-methylcyclohexylamine, o-toluidine to 2-methylcyclohexylamine, and p-toluidine to 4-methylcyclohexylamine in 97%, 96.7% and 98.2% yields,respectively, at 30 C and under atmospheric hydrogen pressure. The yields were remarkably affected by the Pt content in the complex, the kind of solvent and the reaction temperature. The catalyst was very stable and could be reused several times without remarkable change in the catalytic activity.
    New Chiral Metal Cluster Systems for Catalytic Asymmetric Syntheses of Chiral Alcohols
    LI Yan-yun, CHEN Jian-shan, YANG Chuan-bo, DONG Zhen-rong, LI Bao-zhu, ZHANG Hui, GAO Jing-xing, TAKAO Ikariya
    2004, 20(2):  180-184. 
    Abstract ( )   PDF (259KB) ( )  
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    The efficient chiral Ru3(CO)12 systems were prepared in situ from Ru3(CO)12 and various chiral diiminoor diamino-diphosphine tetradentate ligands. The systems have been used for the asymmetric transfer hydrogenation of propiophenone in 2-propanol, leading to 1-phenyl-1-propanol in a 98% yield and 96% e.e. The IR study suggests that the carbonyl hydride anion [HRu3(CO)11]- most probably exists as a principal species under the reaction conditions. The high chiral efficiency may be due to the synergetic effect produced by the neighboring ruthenium atoms and a special chiral micro-environment involving the polydentate ligand and the Ru3 framework.
    Adsorption Mechanisms of Mesoporous Adsorbents in Solutions
    WU Zhi-jian, LEE Kangtaek
    2004, 20(2):  185-187. 
    Abstract ( )   PDF (167KB) ( )  
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    Sieve effect, complexation, ionic exchange, electrostatic interaction, hydrogen bonding, hydrophobic interaction, and molecular recognition based on molecular imprinting are comprehensively discussed.
    Studies on Epitaxial Polymerization of 1,3-Bis(3-quinolyl)-1,4-butadiyne
    LI Tie-Sheng, Shuji Okada, Hachiro Nakanishi
    2004, 20(2):  188-190. 
    Abstract ( )   PDF (164KB) ( )  
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    During investigating what causes the low yield of the polymerization product of 1,4-bis (quinolyl)-1, 3-butadiyne(DQ), we found that the DQ crystals formed on the surface of PDQ cauld be polymerized to give blue crystals, in which DQ could be sublimated and crystallized on the surface of PDQ film. According to the experimental results, the reason why the DQ crystals can be polymerized is that the sublimation of DQ changes the molecular orientation of DQ in the crystal. The crystals formed in epitaxial growth on the surface of DQ or PDQ during sublimation of DQ are suitable for 1,4-addition polymerization.
    Molecular Design of Synthetic Biodegradable Polymers as Cell Scaffold Materials
    WANG Shen-guo, WAN Yu-qing, CAI Qing, HE Bin, CHEN Wen-na
    2004, 20(2):  191-194. 
    Abstract ( )   PDF (214KB) ( )  
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    Poly(lactic acid) and its copolymers are regarded as the most useful biomaterials. The good biocompatibility, biodegradability and mechanical properties of them make the synthetic biodegradable polymers have primary application to tissue engineering. The advantages and disadvantages of the synthetic biodegradable polymers as cell scaffold materials are evaluated. This article reviews the modification of polylactide-family aliphatic polymers to improve the cell affinity when the polymers are used as cell scaffolds. We have developed four main approaches: to modify polyester cell scaffolds in combination of plasma treating and collagen coating; to introduce hydrophilic segments into aliphatic polyester backbones; to introduce pendant functional groups into polyester chains; to modify polyester with dextran. The results of the cell cultures prove that the approaches mentioned above have improved the cell affinity of the polyesters and have modulated cell function such as adhesion, proliferation and migration.
    Measurement and Correlation of Equilibrium Data for Aqueous Two-phase System Ethanol+ Water+ K2HPO4
    LIN Jin-qing, TAN Ping-hua, JIN Chun-ying, LI Ming-chun
    2004, 20(2):  195-199. 
    Abstract ( )   PDF (2428KB) ( )  
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    The isothermal solubility data of aqueous two-phase system ethanol+ water+ K2HPO4 were determined with the turbidity titration method at 303.2 K. The binodal curves were described by using the Mistry equation very well. An experimental procedure for measuring the liquid-liquid equilibrium data of the aqueous two-phase system was proposed, in which the concentrations of the coexisting phases were determined with the corresponding densities of the solution. The tie lines were satisfactorily described by using the Othmer Tobias and Bancroft equations.
    A Study of Ca-Mg Silicate Crystalline Glazes--An Analysis on Forms of Crystals
    LIU Pei-de, YU Ping-li, WU Ji-huai
    2004, 20(2):  200-204. 
    Abstract ( )   PDF (328KB) ( )  
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    In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena,such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors:(1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace,when crystals crystalize from silicate melt ; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.
    Influence of Modification of Counter Electrode on Photoelectric Properties of Dye-sensitized TiO2 Solar Cells
    HAO San-cun, FAN Le-qing, WU Ji-huai, HUANG Yun-fang, LIN Jian-ming
    2004, 20(2):  205-209. 
    Abstract ( )   PDF (265KB) ( )  
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    A dye-sensitized nanocrystalline TiO2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performance when the electrode was modified by platinum than by nickel and carbon. The influence of the incidence light wavelength on the incidence monochromatic photoelectric conversion efficiency(IPCE) was investigated.The result shows that the IPCE mainly depends on the short-circuit current density(ISC) of a DYSC, and the IPCE reaches 48.32% under the irradiation with the wavelength of 560 nm when the counter electrode of a DYSC was modified by platinum. The influence of incident light intensity on the photoelectric properties of a DYSC was also investigated. It was found that the ISC and open-circuit voltage(VOC) increased and the fill factor(ff) of the DYSC decreased with the increase of the incident light intensity.
    N,N-Dilauryl Chitosan:Synthesis and Surface Pressure-area Isotherm
    WANG Min, LI Ming-chun, LIU Chao, SUN Duo-xian, MITSUISHI Masaya, MIYASHITA Tokuji
    2004, 20(2):  210-212. 
    Abstract ( )   PDF (253KB) ( )  
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    With sodium dodecyl sulfonate(SDS) as the phase transferring catalyst, N,N-Dilauryl chitosans with a high degree of alkyl group substitution were prepared and characterized by means of FTIR, 1H NMR and elemental analyses. The results indicate that the average degree of alkyl group substitution on the chitosan increases with decreasing the molecular weight of the chitosan. The fully N,N-dilaurylated chitosan was found to be dissolvable in chloroform. The collapsed pressures of the samples derived from chitosan with 3000,5000 and 10000 dalton are 47.6, 48.2 and 51.0 mN/m, respectively. The surface area occupied by the monomer unit (glucosamine) of all those samples is 0.6 nm2.
    Microwave Irradiation Promoted Synthesis of Aryloxy Acetic Acids
    LIN Min, ZHOU Jin-mei, XIA Hai-ping, YANG Rui-feng, LIN Chen
    2004, 20(2):  213-215. 
    Abstract ( )   PDF (165KB) ( )  
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    Several aryloxy acetic acids were synthesized under microwave irradiation. The factors, which affect the reaction, were investigated and optimized. It was revealed that the best yields(92.7%-97.4%) were obtained when the molar ratio of the reactants was n(ArOH) : n(NaOH): n(ClCH2CO2H) =1: 2.5: 1.2 with microwave irradiation power of 640 W for 65-85 s.
    Syntheses of Some Organic Fluorescent Dyes for Security Tickers
    LI Jun-fen, BAI Guan, LIN Pei-hua, TIAN Mei-lin, DONG Chuan, LI Du-xin
    2004, 20(2):  216-220. 
    Abstract ( )   PDF (1826KB) ( )  
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    Five organic fluorescence dyes were synthesized by two- or three-step reactions. These synthetic methods have an advantage of the simple processes, low costs and high yields. The compositions of the five compounds are characterized by IR, 1H NMR, elemental analyses and fluorescence spectroscopies. The quantum yields of fluorescence were measured.
    Synthesis and Flocculation Property of Chitosan-Acrylamide Graft Copolymer
    LI Liu-zhu, MAO Lu-yuan, WANG Xiu-li, YANG Yong, ZHUANG Yin-feng
    2004, 20(2):  221-224. 
    Abstract ( )   PDF (209KB) ( )  
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    Chitosan, as a kind of natural polymer, has many advantages, such as abundant sources, biological degradation, no secondary contamination and facile modification. In this work, we prepared modified chitosan flocculants with double electrical behavior via polymerizing chitosan, acrylamide and sodium carboxymethyl cellulose together by using ammonium persulfate as the indicator in water. The product is a comb-type of chitosan copolymer and a polymeric ampholyte. And then we studied the product by FTIR, UV-Vis, TG, DSC spectrometeries and viscometry, etc. We also performed CACM′s water treat experiment. The effects of pH values, reaction time and dose of the new floccalant on treating various of waste water have been investigated, too.
    Preparation and Properties of HBS Lignin from Masson Pine
    CHENG Xian-su, CHEN Wei-jian, CHEN Yun-ping, CHEN Yue-xian, LI Mian-jun, FANG Hua-shu
    2004, 20(2):  225-228. 
    Abstract ( )   PDF (194KB) ( )  
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    In order to establish a new method for making cellulose and lignin from Masson pine, a high boiling solvent (HBS) pulping process with an aqueous solvent of 1,4-butanediol was investigated. Masson pine chips were pulped with a 70%-90% aqueous solution of 1,4-butanediol containing a small amount of a catalyst at 200-220 ℃ for 60-180 min. HBS Masson pine cellulose is suitable for making paper. Water-insoluble HBS lignin was separated from the liquor reaction mixture by water precipitation. The recovered high boiling solvent (RHBS) is able to be recycled as a pulping solvent, indicating that the HBS method is a pulping process of Masson pine which is energy saving, resources saving and pollution free. HBS lignin has a better chemical reactivity and a lower ash content than lignin sulfonate.
    Application of Hydrosoluble Polymers to Preparation of Nanoscale Calcium Hydroxide
    XU Jing, CHEN Qing-hua, QIAN Qing-rong
    2004, 20(2):  229-231. 
    Abstract ( )   PDF (175KB) ( )  
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    Calcium hydroxide with uniform diameters about 50—100 nm was firstly prepared under moderate condition by adding different kinds of hydrosoluble polymers. From the results of TEM and IR, the polymers were proved not only to improve the agglomeration of the nanoparticles but also to be used as a template to control the formation of the special structure and the needed size of Ca (OH)2 by changing the concentration of the polymers. The experimental results of TG-DTA indicate that the Ca(OH)2 can absorb most of the acid gases released during the decomposition of polymers. So this kind of nano-Ca(OH)2 can be used as a useful additive of environmental friendly plastics.
    Synthesis and Biodegradation of St-g-poly(MMA-co-VAc) Initiated by Manganic Pyrophosphate
    ZHU Lin-hui, CHEN Mi-feng, JI Yan, XIA Hai-ping, DING Ma-tai
    2004, 20(2):  232-235. 
    Abstract ( )   PDF (220KB) ( )  
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    Methyl methacrylate (MMA) and vinyl acetate (VAc) were grafted onto corn starch with manganic pyrophosphate { [Mn(H2P2O7)3]3-} as the initiator and water as the reaction medium. The influences of reaction conditions, including pH value, initiator concentration, monomer concentration and its composition, on percent grafting and grafting efficiency were investigated. The graft copolymer was characterized by means of IR spectroscopy, scanning electron micrograph(SEM) and 1H NMR spectroscopy. The biodegradation experiment showed that the degradation of corn starch-g-poly(MMA-co-VAc) was mainly from starch. However,after poly VAc in the side chain was transformed into poly vinyl alcohol(PVA), both starch and the grafted side chain could be degraded completely.
    Quick pH-responsive Films Prepared from Urethane Acrylate Anionomers Under UV Radiation and Their Responsive Performances
    TANG Li-ming, DAI Yu, Fang Yu
    2004, 20(2):  236-239. 
    Abstract ( )   PDF (205KB) ( )  
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    Urethane acrylate anionomers(UAA) were prepared in various compositions by three steps. Under UV radiation, UAA formed pH-sensitive films with drying film thicknesses of 60, 200 and 330μm. The equilibrium swelling ratios(SR) of the films in various pH buffer solutions increased with the increase of the molecule weight of UAA. The influence of the film thicknesses on the swelling performances of the films was investigated. The film with a thickness of 60 μm could reach the equilibrium state in 2.5—3.5 min. A high SR was obtained for a thick film due to its low average network density. The cured film could swell reversibly and rapidly with the change of pH, which is important for a controlled release system.
    Polymerization of o-Phenylenediamine Catalyzed by Hemeproteins Encapsulated in Reversed Micelle
    YANG Yong, MAO Lu-yuan, LI Liu-zhu, LIU Xiao-guang, SHI Jun, CAO Shao-kui
    2004, 20(2):  240-243. 
    Abstract ( )   PDF (220KB) ( )  
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    Hemeproteins encapsulated in reversed micelle formulated with di-2-ethylhexyl sulfosuccinate (AOT)was found to catalyze the polymerization of o-phenylenediamine (o-PDA) with hydrogen peroxide, whereas o-PDA catalyzed by hemeproteins dissolved in water could only form its trimers. As the nanostructural environment in reversed micelle acts as a certain orientation surrounding medium, it offers a strong electrostatic field that alters the reductive potential of Fe3+/Fe2+ (Em7) in the heme of hemeproteins and thus increases the catalytic activity of peroxidase accordingly. According to the results of UV-Vis, 1H NMR and FTIR, the polymer catalyzed by hemoglobin(Hb) in reversed micelle was presumed to be constructed of lines and trapeziforms alternatively.
    Preparation and Catalytic Properties of Polymer-Bound Schiff Base Ternary Complexes
    HAO Cheng-jun, WANG Rong-min, HE Yu-feng, WANG Yun-pu, XIA Chun-gu
    2004, 20(2):  244-247. 
    Abstract ( )   PDF (210KB) ( )  
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    The polymer-bound Schiff base ternary manganese complexes [PS-SalPhe-Mn-L (L = Phen, Bipy and 8HQ)] have been prepared from the polymer-bound Schiff base ligand, a manganese salt and the second ligand, such as 1,10-phenanthroline(phen), 2,2′-bipyridyl(bipy) and 8-quinolinol(8HQ). The polymer-bound Schiff base ternary manganese complexes were characterized by means of infrared spectrometry and ICPAES. The catalytic activities of the complexes have been studied in the aerobic epoxidation of long-chain linear a[iphatic olefins. It is shown that 1-octene or 1-decene can be directly oxidized by molecular oxygen when catalyzed by PS-SalPhe-Mn-L(L=Phen, Bipy and 8HQ), and 1,2-epoxy alkane can be afforded in these reactions.
    Influence of Reactive Diluent on UV-curing of Acrylate Terminated Hyperbranched Polymers
    TANG Li-ming, FANG Yu, YAN Liang, FU Zhi-wei
    2004, 20(2):  248-252. 
    Abstract ( )   PDF (347KB) ( )  
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    A Aeries of hydroxylic hyperbranched polymers were derived from 2,2-bis(methylol) propionic acid and tris (methylol) propane reacted with acrylic acid to various extents. The obtained acrylated hyperbranched polymers alone or with a monofunctional diluent, isobornylene acrylate(IBOA) were further cured by UV radiation. The cured films based on the modified polymers alone all demonstrated poor mechanical properties due to their high network densities and low moving ability of polymer chains. For the composite systems, the cured films demonstrated improved mechanical properties due to the low network densities and high chain moving ability. With more IBOA included in the systems, acrylate groups can react to a higher extent during the curing process.
Editor-in-Chief:
Jihong YU
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CN 22-1183/O6
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