Electrochemical and spectral properties of the polymer form of Cu(II) complex with N,N′-bis(salicylidene)-1,3-propylenediamine

A conductive polymer based on the Cu(II) complex with N,N′-bis(salicylidene)-1,3-propylenediamine was obtained electrochemically. The optimal mode of the synthesis of the polymer under potentiostatic conditions was found. We determined the charge diffusion coefficient and activation barrier and elucidated the nature of the limiting step of the charge transfer in the polymer bulk in the electrolyte medium. The azomethine base, Cu(II) complex, and its polymer form in the oxidized and reduced states were characterized by X-ray photoelectron spectroscopy and electron absorption spectroscopy.     

Acrylation of polyvinylsilazane with allyl bromide for an UV photosensitive inorganic polymer

A novel inorganic polymer resin with high photosensitivity was prepared by grafting acrylate functional groups onto the backbone of polyvinylsilazane through a reaction with methyl-2-(bromo-methyl)acrylate via the highly efficient electrophilic substitution of allyl bromide. The as-modified polymer was characterized by ¹H NMR and 2D-¹H-¹H NMR (COSY) methods to determine the reaction mechanism. Differential photocalorimetry, FT-IR spectroscopy and TGA were used to examine its properties. The modified polyvinylsilazane is a promising inorganic polymer photoresist with a high UV sensitivity and a 55% ceramic yield, which is useful for fabricating non-oxide ceramic microstructures using mold free photocuring shaping processes.     

Preparation and properties of poly[9-hexadecyl-3-phenyl-6-(4-vinylphenyl)-9H-carbazole]

Preparation of new carbazole-containing polymer, poly[9-hexadecyl-3-phenyl-6-(4-vinylphenyl)-9H-carbazole], is reported. The optical properties of the product have been studied in comparison with those of the starting compounds. Electrochemical properties of the polymer solution and its thin film have been investigated. The polymer film images were obtained by atomic force and scanning tunneling microscopy. Thermogravimetric analysis has shown high thermal stability of the obtained polymer.     

Development of a monolithic polymer pipette for solid-phase extraction of liquiritigenin in rat plasma

A monolithic polymer column with mixed-mode interaction was prepared by in situ polymerization in a 1000μL pipette.Two kinds of monomers,butyl methacrylate(BMA) and 2-(dimethylamino)ethyl methacrylate(DMAM) were applied to constructing the mixed-mode interaction of monolithic polymer column.Its solid-phase extraction properties for liquiritigenin(LQG) were evaluated by high performance liquid chromatography(HPLC) with a gradient elution procedure.After the extraction procedure was optimized,the maximum binding capacity and extraction recovery following the optimal extraction procedure were investigated.Calibration curve was expressed as A = 65.9C + 4.53(r~2 = 0.998) with a linear range of 0.151-1.80μg/mL.The experimental results indicate that the monolithic polymer pipette presents good extraction efficiency for LQG.It can be envisaged that the developed monolithic polymer pipette possesses the potential for its application to the enrichment of other flavonoids compounds being similar to the structure of LQG.     

Fabrication of dendritic gold nanoparticles by use of an ionic polymer template

A facile method for the fabrication of dendritic gold nanoparticles (NPs) by use of an ionic polymer template has been developed. In situ generation of an imidazolium-based (cationic) polymer, poly[1-methyl-3-(4-vinylbenzyl)imidazolium], with AuCl4- counteranions is achieved by addition of HAuCl4 into a solution containing poly[1-methyl-3-(4-vinylbenzyl)imidazolium chloride]. Subsequent reduction with NaBH4 in water or in a mixture of ethanol and water affords various NPs depending on the conditions, including large dendritic gold NPs that have been analyzed by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and selected area electron diffraction (SAED). The structures of the dendritic gold NPs were found to depend on the ethanol concentration. Scanning electron microscopy (SEM) images of the ionic polymer reveal that the solvent used to deposit the polymer strongly influences its structure and may be correlated to the structure of the resulting NPs.     

Thermosensitive and salt-sensitive molecularly imprinted hydrogel for bovine serum albumin

A novel stimuli-responsive protein imprinted polymer for selective recognition of bovine serum albumin is presented. N-[3-(Dimethylamino)propyl]-methacrylamide, which is positively charged in neutral solution and is able to self-assemble onto the template protein through electrostatic interaction, was chosen as the functional monomer. Polymerization was carried out in the presence of N-isopropylacrylamide as an assistant monomer, which resulted in a stimuli-responsive protein imprinted polymer. The template proteins were easily removed by treatment with 500 mmol L(-1) NaCl solution. The influences of the external stimuli, such as temperature and ionic strength, on the polymer affinity were investigated, and a clear conformational memory was observed. The association constant ( Ka) and binding capacity ( Qmax) for the specific interaction between the protein imprinted polymer and the template protein were determined by Scatchard plots and found to be 9.6 x 10(4) L mol(-1) and 4.7 micromol g(-1), respectively. Several proteins different in molecular weight and isoelectric point were employed as reference, and it was shown that the charge effect and the shape memory effect were the major factors affecting the imprint formation and template recognition. Finally, this imprinted polymer was used to purify the bovine serum albumin from the protein mixture and real sample, which demonstrated its high selectivity.     

Emulsion polymerization of vinyl chloride, 2 potassium persulfats decomposition in the presence of PVC latex

The decomposition rate of potassium persulfate (KPS) in aqueous solutions, in the presence of sodium dodecyl sulfate (SDS) and poly(vinyl chloride) latex (PVC) was studied. The dissolved SDS increases the decomposition rate constant (k_d) while the SDS aggregation as micella and/or its adsorption on the polymer hydrophobic surface results in a decreasing k_d. The emulsifier - free surface of the polymer particles increases the decomposition rate. A reaction mechanism based on emulsifier - emulsifier and emulsifier - polymer hydrophobic interactions is put forward.     

一种新型聚合物电解质的研制

合成了聚 (甲基丙烯酸甲酯 丙烯腈 甲基丙烯酸锂 ) (简记为PMAML)新型聚合物电解质基质材料 ,把它与聚偏氟乙烯 (PVDF)共混制备了凝胶化的聚合物电解质 .通过核磁共振波谱确定了PMAML的组份含量 ,并用扫描电镜观察了该聚合物基质膜的表面形貌 .利用交流阻抗技术测试了其电导率 ,室温下电导率可达2 5× 10 - 3S·cm- 1 .采用线性伏安扫描方法研究了该聚合物电解质的电化学稳定性 ,其电化学稳定窗口为4 5V .通过受限扩散实验测得电解质中离子的扩散系数为 8 12× 10 - 7cm2 ·s- 1 .组装的聚合物电解质锂离子电池首次充放电效率为 89% ,前 5次循环容量基本稳定 .     

原位分子印迹法制备的连续棒型模板聚合物的手性识别

使用Ｒ－１－（１－萘基）乙胺为模板分子,α－甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,采用原位分子印迹分子制备了具有手性识别环境的连续棒型模板聚合物。色谱结果表明,这种连续棒型模板聚合物对模板分子Ｒ－１－（１－萘基）乙胺比对它的对映异构体Ｓ－１－（１－萘基）乙胺及其外消旋体具有更长的保留时间,更大的容量因子,展现了一定的手性识别能力。     

A novel antibody immobilization and its application in immunoaffinity chromatography

A novel antibody immobilization and its application in immunoaffinity chromatography (IAC) were presented. Using acrylamide (AM) as monomer, ethylene glycoldimethacrylate (EGDMA) as cross-linker and bulk polymerization as synthetic method, we prepared a polymer in which the Cu(II) was embedded. The Cu(II)-embedded polymer was tested for its binding with protein. It was found that Cu(II)-embedded polymer displayed a strong binding with bovine serum albumin (BSA). At 80% of methanol, no BSA was released from Cu(II)-embedded polymer. The Cu(II)-embedded polymer was then used as a novel solid support for antibody immobilization. IAC column was prepared by immobilizing polyclonal antibody (pAb) against clenbuterol (CL) on Cu(II)-embedded polymer and packing the Cu(II)-embedded polymer-pAb into a common solid phase extraction (SPE) cartridge. Under optimal extraction conditions, the IAC column was characterized in terms of maximum binding capacity for target analyte, extraction efficiency and reusability. It was revealed that, for IAC column packed with 0.1 g of solid support immobilized with antibody, the maximum capacity for CL was 616 ng; the extraction recoveries of the column for CL from three spiked food samples were 84.4-95.2% with relative standard deviation (RSD) of 9.3-15.5%; after more than 30 times repeated usage, there was not significant loss of specific recognition. The results demonstrated the feasibility of the prepared IAC column for CL extraction. The proposed antibody immobilization method exhibiting the properties of simplicity, low cost, strong binding for target analyte, no leaching of antibody, etc., would be a very useful tool applied in the field of IAC.     

一种新型低带隙共轭聚合物的合成及其光学性质

在钯催化剂作用下, 通过4,7-二(5-溴-2-噻吩基)[2,1,3]苯并噻二唑与2,5-二乙炔基-3-辛基噻吩的偶联反应, 合成了一种新的共轭高分子聚4,7-二(2-噻吩基)苯并噻二唑-3-辛基噻吩二炔(PTE-DTBT). 通过紫外可见吸收光谱及荧光光谱对其光学性质进行了研究. 紫外-可见吸收谱结果表明, PTE-DTBT的固体膜光学带隙为1.71 eV; 电化学测试其带隙为1.88 eV. TiO₂/PTE-DTBT共混固体膜的荧光发射谱结果表明电子供体PTE-DTBT分子与电子受体TiO₂分子间存在有效的电子转移.     

Circular dichroism of polyethylenimine containing optically active thymine derivatives as grafted pendants

Optical properties of linear polyethylenimine containing optically active (+)- or (?)-2-(thymin-1-yl)propionyl group as grafted pendant were investigated by circular dichroism (CD) and compared with those of the related monomer and dimer model compounds. CD spectra of the polymer in neutral aqueous solution were different from those of related model compounds, which suggest that the polymer exists in some ordered conformation (at least locally) to allow exciton coupling of π–π^* (B_2u) transition in the base chromophores along the polymer chain. This ordered conformation tends to be randomized on heating. The effects of complementary base pairing on the CD spectra have also been studied by using a linear polyethylenimine containing (±)-2-(adenin-9-yl) propionyl grafts and its related monomer and dimer models.     

Synthesis of optically active polymers using P-chiral bisphosphines as anionic initiators

Anionic polymerization of triphenylmethyl methacrylate was performed by using P-chiral bisphosphine initiators. According to the optical rotation analysis and circular dichroism measurements, the polymer obtained by using the initiator (S,S)-1,2-bis(boranato(tert-butyl)methylphosphino) ethane exhibited one-handed helical conformation induced by the chirality of phosphorus atoms in the polymer terminal. The enantiomer (R,R)-1,2-bis(boranato(tert-butyl)methylphosphino) ethane gave the opposite one-handed helical polymer. Optically active bisphosphine (S,S)-1,2-bis(boranatomethylphenylphosphino) ethane was employed for the helix-sense-selective polymerization of triphenylmethyl methacrylate in order to obtain the polymer with the same helix sense as the polymer obtained from the initiator (S,S)-1,2-ethane bis(t-butylm-ethylphosphineborane). Further, removal of the coordinated boranes and complexation with platinum(II) on the chiral phosphorus atoms were carried out in order to yield the corresponding polymer-platinum(II) complex without loss of its chiral higher-ordered structure.     

Association thickener by host guest interaction of a β-cyclodextrin polymer and a polymer with hydrophobic side-groups

A host polymer with pending β-cyclodextrin side-groups and a guest polymer with pending hydrophobic 4-tert-butylanilide side groups were synthesized by polymeranalogous reactions starting from poly[(maleic anhydride)-alt-(isobutene)] (M̄_w = 60000). The inclusions of both polymers with complementary monomeric guests and hosts are proven by microcalorimetry. The interaction of the host polymer and the guest polymer in aqueous solution is accompanied by a tremendous increase in viscosity.     

STUDIES ON SELF-ASSOCIATIVE BEHAVIOR OF A NOVEL CATION AMPHIPHILIC POLYMER

A novel associating polymer P(AEBA) was synthesized by radical polymerization of the cationic amphiphilic monomer,4-(2-(acryloyloxy)ethoxy)benzyl tri-ethyl ammonium bromide(AEBA),in aqueous solutions.P(AEBA) displays a strong tendency for self-association in aqueous solutions and is sensitive to the external stimulation such as added salt.The associative properties and morphologies of P(AEBA) were studied by fluorescnece probe technique,viscometry and TEM.In dilute salt-free solutions P(AEBA) behaves as ...     

Vapor deposition polymerization of heteroatom-bridged [2.2]paracyclophanes: 1,9-dithia[2.2]paracyclophane and 1,9-dithia[2.2]paracyclophane-1,1,9,9-tetroxide

1,9-Dithia[2.2]paracyclophane-1,1,9,9-tetroxide ( 3 ) was synthesized as white needles in a high yield from 1,9-dithia[2.2]paracyclophane ( 2 ) by oxidation with m-chloroperbenzoic acid, and its molecular structure was determined with single-crystal X-ray diffraction analysis. Vapor deposition polymerizations of 2 and 3 gave amorphous and brittle polymer films along with considerable amounts of nonpolymeric byproducts. A polymer film from 2 was a copolymer of p-(phenylene-methylenesulfide) with p-(phenylene-methylene) units, and a polymer film from 3 was a homopolymer of p-(phenylene-methylene) units with head-to-tail, head-to-head, and tail-to-tail placements. The elimination of sulfur atoms in 2 and sulfone units in 3 took place during their pyrolysis reactions. Plausible mechanisms for vapor deposition polymerizations of both cyclophanes are proposed. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1892–1900, 2001     

POLYBINAPHTHYLS INCORPORATING (R)-2,2’-BINAPHTHO-20-CROWN-6 AND NAPHTHYL MOITIES

Chiral polymer was synthesized by the polymerization of （R）-6,6＇-bistributylstannyl-2,2＇-binaphtho-20-crown-6 （M-1） with 1,4-dibromo-2,3-bisbutoxy-naphthyl （M-2） by Pd（PPhs）4 catalyzed Stille coupling reaction. Both monomer and polymer were analyzed by NMR, MS, FT-IR, UV, polarimetry, DSC-TGA, CD, fluorescent spectroscopy and GPC. The major difference between monomer and polymer is that a long wavelength Cotton Effect was observed for the polymer due to its more extended conjugation in the repeating unit and a highly rigid backbone in the polymer chain. Polymer has strong blue fluorescence due to the efficient energy migration from the extended n-electronic structure of the repeating unit of the polymer to the chiral binaphthyl core and is expected to have potential application in the materials of fluorescent sensors and chiral chromatographic packing for resolution ofracemic amino acid.     

Incommensurate structures investigated by X-ray studies of electropolymerised methacrylic monomer with TiO2 nanoparticles

We explore the possibility of producing polymer nanocomposites with an ordered distribution of nanoparticles by using an electropolymerizable liquid crystal (LC) monomer. The nanoparticles are added to the monomer before polymerizing it. We study the polymer derived from the LC (E)-6-(3-hydroxy-4-(((4-octyloxy)phenyl)imino)methyl)phenoxy)hexyl methacrylate (M6R8) both pure and in the presence of 3.4 nm TiO₂ nanoparticles, at 30 wt%. This particular system is chosen since (1) the LC polymers we work with have the added advantage of having a specific orientation and structure which allows us to study its effect in the nanoparticles and (2) when considering the nanocomposite, it is polymerized with the nanoparticles included. The system is studied using grazing incidence small angle X-ray scattering and in-plane direction X-ray scattering. The polymer obtained alone appears to be tilted with respect to the surface of the substrate. The structure adopted by the nanoparticles in the nanocomposite is layered and apparently incommensurate with the polymer. It is formed through the association of the nanoparticles with the M6R8 aromatic cores during the process of electropolymerisation. This interpretation of the data is supported by the nanoparticle structures formed when the related, non-polymerizable LC, (E)-6-(3-hydroxy-4-(((4-octyloxy)phenyl)imino)methyl)phenoxy)hexyl isobutyrate (I6R8), is analysed. We find that for both, the pure polymer poly-((E)-6-(3-hydroxy-4-(((4-octyloxy)phenyl)imino)methyl)phenoxy)hexyl) methacrylate (EPM6R8) as well as the polymer with nanoparticles (EPM6R830TO), the electropolymerisation imposes a preferred growth direction of the polymer side chains, and therefore for the nanoparticle arrangement in the polymer.     

P(VAc-MA)/PMMA为基体的聚合物电解质制备及其在电致变色器件中的应用

以醋酸乙烯酯(VAc)和丙烯酸甲酯(MA)为单体, 采用半连续种子乳液聚合法制备了无规共聚物P(VAc-MA), 以PMMA与P(VAc-MA)的共混物为基体制备了聚合物电解质. 用红外光谱(FTIR)、X射线衍射(XRD)、热重分析(TG)、紫外光谱(UV)、力学性能测试及电化学交流阻抗等方法研究了聚合物、聚合物膜和聚合物电解质的性质. 结果表明, VAc与MA通过打开各自的CC键聚合生成P(VAc-MA); P(VAc-MA)与PMMA共混后结晶状态发生了变化, 增加了无定形相区, 降低了链段运动的能量壁垒, 提高了热稳定性和拉伸强度. 以P(VAc-MA)/PMMA为基体的聚合物电解质膜具有很高的透明性, 最大室温电导率达到1.17×10-3 S/cm; 离子电导率随着温度的升高而迅速增加, 电导率-温度曲线符合Arrhenius方程; 将此电解质用于全固态电致变色显示器件显示出优良的性能.     

Analysis of herbicides in water using temperature-responsive chromatography and an aqueous mobile phase

A simple and rapid method has been developed for herbicides in water using temperature-responsive liquid chromatography (LC) and a column packed with poly(N-isopropylacrylamide) (PNIPAAm), a polymer anchored on the stationary-phase surface of modified silica. PNIPAAm reversibly changes its hydrophilic/hydrophobic properties in water in response to temperature. The method was used to determine five sulfonylurea and three urea herbicides. Separation was achieved with a 10 mM ammonium acetate (pH 3.0) isocratic aqueous mobile phase, and by changing the column temperature. The analytes were extracted from water by off-line solid-phase extraction (SPE) with an N-vinyl-pyrrolidone polymer cartridge. The average recoveries of the eight herbicides from spiked pure water, tap water and river water were 70-130% with relative standard deviations (RSDs) of <10%. The limits of quantitation (LOQ) of the eight herbicides were between 1 and 4 microg l(-1).