Preparation of polyacrylamide/silica composite capsules by inverse Pickering emulsion polymerization

Polyacrylamide/silica （PAM/SiO2） composite capsules were synthesized by inverse Pickering emulsion polymerization. Silica nanoparticles modified with methacryloxypropyltrimethoxysilane （MPS） were used as a stabilizer. Transmission electron microscopy （TEM）, scanning electron microscopy （SEM）. Fourier transform infrared （FTIR） spectroscopy, and thermal gravimetric analysis （TGA） were used to characterize the morphology and composition of the composite capsules. SEM and TEM images showed that capsules consisted of a particle shell and a polymer inner layer. The capsule size depends on the nanoparticle concentration in the continuous phase. The composite rigidity largely depends on the acrylamide concentration. FTIR and TGA results indicated the existence of polyacrylamide and SiO2 in the composite particles. Aqueous Hg（ll） removal testing by the PAM/SiO2 composite capsules indicated promising potential for removing heavy metal ions from wastewater.

PHOTOSENSITIVITY OF CERIC ION INITIATED METHYL ACRYLATE POLYMERIZATION

The polymerization of methyl acrylate was sensitive to UV light. Under UV light,the rate of polymerization is 8 times as high as the rate in dark.The overall activation energy was decreased by the UV light (313nm).A tentative explanation is given and the mechanism is discussed.

RADICAL POLYMERIZATION OF VINYL MONOMER INITIATED BY CERIC ION/TARTARIC ACID

The polymerization of acrylamide and acrylonitrile using ceric ion as initiator can be promoted greatly by the tartaric acid. The kinetics of acrylamide polymerization initiated by ceric ion/tartaric acid has been studied. The presence of the species of tartaric acid in Polyacrylonitrile produced by using ceric ion/tartaric acid as niitiator has been confirmed by FT-IR analysis.

Ion imprinted polymer particles of neodymium:synthesis,characterization and selective recognition

Neodymium ion imprinted polymer（Nd^3＋-IIP） particles for selective solid-phase extraction of Nd^3＋ were prepared and determined with inductively coupled plasma atomic emission spectrometry（ICP-AES）.The unleached Nd^3＋-IIP particles were prepared by the copoly-merization of Nd^3＋-5,7-dichloroquinoline-8-ol-4-vinylpyridine ternary complex with styrene and divinyl benzene, then Nd^3＋ was leached to obtain Nd^3＋-IIP particles.The adsorption capacity of the Nd3＋-IIP was 35.18 mg/g.The largest selectivity coefficient for Nd3＋ in the presence of competitive ions such as La^3＋, Ce^3＋, Pr^3＋ and Sm^3＋ was over 110.The proposed method was validated by analyzing two certified reference materials（GBW07301a sediment and GBW07401 soil） and the determined values were in a good agreement with standard values.The method was convenient, selective, sensitive and applicable to the determination of trace Nd^3＋ in environmental samples with complicated matrix.

Sensitivity Enhancement in Uranium Determination by UV-Visible Spectroscopy Using Ion Imprinted Polymer

There is need to determination of uranium concentration at ppb level in environmental matrices.Due to low sensitivity of FAAS,UV-Visible Spectroscopy is generally used as measurement technique.In this study,ion-imprinted polymers(IIP)were prepared for uranyl ion(imprint ion)by formation of ternary(salicylaldoxime and 4-vinylpyridine)complex in 2-methoxy ethanol(porogen)following copolymerization with methacrylic acid(MAA)as a functional monomer and ethylene glycol dimethacrylate(EGDMA)as crosslinking monomer using 2,2-azobisisobutyronitrile as initiator.The synthesized polymers were characterized by FTIR and TGA analysis.ArsenazoⅢin 3M HClO_4 was used as complexing agent in the measurement step.The optimal pH for preconcentration was found to be between 3.5~6.5values.The developed method was applied to uranium(Ⅵ)determination in natural water samples.

Electrochemical performance of all-solid lithium ion batteries with a polyaniline film cathode

We have prepared a high-density polyaniline（PANI） paste（50 mg/m L）, with similar physical properties to those of paints or pigments. The synthesis of PANI is confirmed by Fourier transform infrared（FT-IR） spectroscopy. The morphologies of PANI, doped PANI, and doped PANI paste are confirmed by scanning electron microscopy（SEM）. Particles of doped PANI paste are approximately 40–50 nm in diameter, with a uniform and cubic shape. The electrochemical performances of doped PANI paste using both liquid and solid polymer electrolytes have been measured by galvanostatic charge and discharge process. The cell fabricated with doped PANI paste and the solid polymer electrolyte exhibits a discharge capacity of ～87 μAh/cm2（64.0 m Ah/g） at the second cycle and～67 μAh/cm2（50.1 m Ah/g） at the 100 th cycle.

Electronic mobility in the high-carrier-density limit of ion gel gated IDTBT thin film transistors

Indacenodithiophene-co-benzothiadiazole（IDTBT） has emerged as one of the most exciting semiconducting polymers in recent years because of its high electronic mobility and charge transport along the polymer backbone. By using the recently developed ion gel gating technique we studied the charge transport of IDTBT at carrier densities up to 10^21cm^-3.While the conductivity in IDTBT was found to be enhanced by nearly six orders of magnitude by ionic gating, the charge transport in IDTBT was found to remain 3D Mott variable range hopping even down to the lowest temperature of our measurements, 12 K. The maximum mobility was found to be around 0.2 cm^2·V^-1·s^-1, lower than that of Cytop gated field effect transistors reported previously. We attribute the lower mobility to the additional disorder induced by the ionic gating.

EFFECT OF STRUCTURE OF FUNCTIONAL POLYMER ACTIVE MATERIALS ON PROPERTIES OF GADOLINIUM ION SELECTIVE ELECTRODE

In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes.

Dynamic Monte Carlo simulation of chain growth polymerization and its concentration effect

Free radical polymerization and living ion polymerization have been simulated via the dynamic Monte Carlo method with the bond-fluctuation model in this paper. The polymeriza-tion-related parameters such as conversion of monomers, degree of polymerization, average molecular weight and its distribution are obtained by statistics. The simulation outputs are con-sistent with the corresponding theoretical predictions. The scaling relationships of the coil size versus chain length are also confirmed at different volume fractions. Furthermore, the effect of diffusion on polymerization is revealed preliminarily in our simulation. Hence the simulation ap-proach has been proven to be feasible to investigate polymerization reactions with the advan-tages that configuration and diffusion of polymer chains can be examined together with polym-erization kinetics.

A study on hydrolytic polymerization of lanthanide ions

Experimental data of hydrolytic polymerization of lanthanide ions in aqueous solution were treated by graphic method,computer fitting and pq analysis,species present were ascertained and hydrolysis constants obtained.Ln(OH)^(2+)and Ln_2(OH)_2^(4+)predominated in the species of all hydroly- sis products.When the first and the second hydrolysis constants were plotted against radii and ef- fective nuclear charge of lanthanide ions,the curves obtained conformed with the“three-division groups”rule.Correlation between hydrolysis constants of Ln_2(OH)_2^(4+)and other hydrolysis constants is linear. Using the above empirical correlations we calculated hydrolysis constants of all lanthanide ions and obtained satisfactory results which showed good regularity for hydrolysis of lanthanide ions and thus systematized all data of the reaction.

AN IMPRINTED POLYMER FOR REMOVAL OF Cd^(2+) FROM WATER SAMPLES:OPTIMIZATION OF ADSORPTION AND RECOVERY STEPS BY EXPERIMENTAL DESIGN

A new ion-imprinted polymer （liP） was synthesized by copolymerization of 4-vinylpyridine （monomer）, ethyleneglycoldimethacrylate （cross-linker） and 2,2-azobis-isobutyronitrile （initiator） in the presence of Cd2＋ and quinaldic acid （complexing agent）. It was found that the adsorption capacity of IIP and blank polymer were 45.0 and 6.2 mg g-l, respectively. The relative selectivity coefficients of the imprinted polymer for different binary mixture were also calculated. Compared to non-imprinted polymer （NIP）, the IIP had higher selectivity for Cd（II）. The IIP was used as a sorbent for cadmium extraction from water samples by using a simple batch extraction procedure. The effect of different parameters on Cd2＋ extraction and its recovery from the IIP were evaluated and optimized by using experimental design methodology. The optimized adsorption/desorption procedure was applied for cadmium removal from the real water samples. The obtained recoveries proved that this IIP could be used for removal of trace cadmium ions from water samples.

Conjugated polymer-mediated synthesis of sulfur- and nitrogen-doped carbon nanotubes as efficient anode materials for sodium ion batteries

Heteroatom-doped carbon nanomaterials have attracted significant attention as anode materials for sodium-ion batteries （SIBs）. Herein, we demonstrate a conjugated polymer-mediated synthesis of sulfur and nitrogen co-doped carbon nanotubes （S/N-CT） via the carbonization of sulfur-containing polyaniline （PANI） nanotubes. It is found that the carbonization technique greatly influences the structural features and thus the Na-storage behavior of the S/N-CT materials. The carbon nanotubes developed using a two-step carbonization process （heating at 400℃ and then at 900℃） exhibit a high specific surface area, enlarged interlayer distance, small charge transfer resistance, enhanced reaction kinetics, as well as a large number of defects and active sites; further, they exhibit a high reversible capacity of 340 mAh·g^-1 at 0.1 A·g^-1 and a remarkable cycling stability with a capacity of 141 mAh·g^-1 at 5 A·g^-1 （94% retention after 3,000 cydes）. Direct carbonization of conjugated polymers with a specific morphology is an eco-friendly and low-cost technique for the synthesis of dual atom-doped carbon nanomaterials for application in energy devices. However, the carbonization process should be carefully controlled in order to better tune the structure-property relationship.

Thiourea Based Conjugated Polymer Fluorescent Chemosensor for Cu^＋ and Its Use for the Detection of Hydrogen Peroxide and Glucose

A novel conjugated polymer, poly（1）, containing thiourea moieties in main chain is synthesized via Suzuki coupling reaction. The addition of cuprous ion quenches the fluorescence of poly（1）, whereas the fluorescence changes slightly upon addition of other metal ions, exhibiting the fluorescent almost turn-off sensing ability towards Cu~＋. When hydrogen peroxide was added to the solution containing poly（1） and Cu~＋, Cu~＋ was oxidized into Cu^（2＋）, resulting in the fluorescence recovery. The H_2O_2 released from glucose oxidation by glucose oxidase（GOD） also recovered the fluorescence of poly（1）/Cu~＋ solution. The results indicated that the poly（1）/Cu~＋ solution could serve as a sensing platform for hydrogen peroxide and glucose.

Structural behavior of F-in mould flux melt of CaO-SiO2-Al2 O3-Na2O-CaF2 system

The influence of fluorine on the structure of CaO Si（）e-Al2Oa Na2O-CaF2 continuous-casting-type slag was measured by Raman spectroscopy, and the degree of polymerization of mould flux and the structural behavior of F- in the melt were investigated by classifying and quantifying the structural species of F ions. The results exhibit that the main structural units of Si O tetrahedra are Q1, Q1 and Q2, and the actual measured number of non bridging oxygen ions in the [SiO4 ]-tetrahedra （denoted by NBO/T） in creases from 2. 73 to 3.44 with increasing the molar ratio of F to （F＋O） （denoted by XF/X（F-O ） from 0.06 to 0. 19. It means that the degree of polymerization o1 meh structure decreases with an increase in XE/X（F＋O）. In addition, most of F- ions were distributed in Si-O tetrahedra and Al-O tetrahedra. With increasing XF/X（F＋O）, the complex structural units Al-Otetrahedra are gradually replaced hy discrete structural units A1F4 because of the breakage of Al-O bonds in Al-Otetrahedra by F ions, and the SiO （bridging oxygen） bonds of SiO tetrahedra are broken to form [SiOnF1-n]-tetrahedra by F ions coordinating with Si4 ＋ .