Advanced Materials Research Vol. 549

Abstract: Poly (trimethylene terephthalate)/polybutadiene grafted polymetyl methacrylate (PB-g-PMMA, MB) blends were prepared by melt processing with and without diglycidyl ether of bisphenol-A (DGEBA) epoxy resin as a reactive compatibilizer. The rheological and crystallization properties of the prepared blends have been investigated. The complex viscosity of PTT/MB blend increased in the presence of DGEBA at low frequency range. Differential scanning colorimetry(DSC) experiments showed that the melting point of pure PTT and their blends was almost constant. Crystallization points decreased when 1wt% DGEBA added to the blend.

Abstract: Electrooxidation of 4-chlorophenol in acidic solution was studied by cyclic voltammetry and in situ FTIR spectroscopy. Compared with platinum (Pt) and glassy carbon (GC) electrodes, carbon electrode exhibited a high electrocatalytic activity during the electrooxidation reaction of 4-chlorophenol. The possible mechanism of 4-chlorophenol on carbon electrode was studies by in situ FTIR. At first, 4-chlorophenol was electrooxidized to 4-chlorophenolic radical, and then to phenoxylic radical. Then, the radical was electrooxidized to hydroquinone, benzoquinone or unsaturated carboxylic acids with potential increasing. In addition, with the reaction of phenoxyl radicals, the insoluble aromatic ether oligomer generated on the carbon electrode surface and prevented the further oxidation reaction of 4-CP in some degree.

Abstract: The synthesis of carbyne was studied by oxidation polycondensation of acetylene using HClO₄ as the oxidizer, ammonia as the complexing agent, Ag (I) as the catalyst at 35°C with pH 7.0 in aqueous phase and benzene phase respectively. The configuration of carbyne was characterized by FT-IR, and the result showed that carbynes with longer carbon chain were synthesized in benzene by phase-transformation method. The HPLC analysis indicated that polyynes of less than or equal to 16 carbon were transferred to the benzene.

Abstract: Metallic copper nanoparticles were synthesized in the presence of poly(N-vinylpyrrolidone) (PVP) as the capping agent and L-ascorbic acid as the reducing agent in diethyleneglycol (DEG) solvent. The obtained copper nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The EDS and XRD results showed that the resultant particles were confirmed to be crystalline Cu with a face-centered cubic (fcc) structure. It was also observed that the diameter of obtained copper particles ranging from 80 to 120nm via SEM and TEM.

Abstract: Natural plant fibers possess a lot of advantages in chemical modification, such as easy process, extensive intensity range, better selectivity, good resistance to water, biodegradability and photo-degradability, that makes the etherification and esterification wood has good development prospect. In this paper, softwood fibers were used as raw material and epoxy chloropropane as modifier. The influences of epoxy chloropropane dosage, reaction time and temperature, and the dosage of NaOH on the modification were analyzed. Simultaneity, an FTIR study was performed to show the partial substitution of hydroxyl groups by the epoxy group. And surface morphology of fibers modified was characterized by scanning electron microscope.

Abstract: Sorbent of CuO loaded on complex carrier of attapulgite and activated carbon was prepared by incipient impregnation method for flue gas desulfurization. The effects of CuO loading, reaction temperature and components in flue gas on the desulfurization performance were investigated in a fixed-bed quartz reactor. The experimental results indicate that the sorbents of 20 wt% CuO loading has a high desulfurization activity under conditions of reaction temperatures 200-250 oC and 21000 h^-1, and O₂ is necessary for the high desulfurization activity of the sorbents.

Abstract: This work is directed towards the preparation of chemoselective ruthenium catalyst. The catalyst is a new type of ruthenium(II) complexes supported on γ-Al₂O₃, which have ruthenium(II) centers coordinated to the ligands triphenylphosphine and (1S,2S)-1,2-Diphenyl-1,2-ethanediamine. The catalyst for the selective hydrogenation of ketones in the mild conditions is investigated. The results show that the performance of the catalystis greatly influenced by the ratio of Ru and PPh₃ and reduction time, respectively.

Abstract: MCM-56 zeolite has been synthesized by dynamic hydrothermal method. The template of as-made MCM-56 was removed by two methods. One is traditional calcination, the other is hydrogen peroxide post-treatment. All materials were characterized by different techniques, such as XRD, N2 adsorption-desorption, NH3-TPD and FTIR. Results show that the template of as-made MCM-56 could be removed effectively by hydrogen peroxide post-treatment. The topology of the hydrogen peroxide treated MCM-56 remains unchanged. The BET surface area and external surface area of MCM-56 zeolite could be obviously improved by hydrogen peroxide treatment. The amount of acid sites was increased by hydrogen peroxide treatment but the acid strength was not modified.

Abstract: In present study, a few polysulfone composite membranes with the introduction of silver ion-exchange treated zeolite were prepared and evaluated by several characterization methods. Regularly-ordered zeolite particles were generally finely dispersed in the continuous PSF phase with appreciated organic-inorganic interfacial interactions as reflected by SEM and FTIR results. Gas permeation test shows that after incorporating zeolite the polysulfone membrane exhibits significantly decreased gas permeability for H₂, N₂, and CO₂ whereas they show increased permselectivity for CO₂/N₂, H₂/CO₂ and H₂/N₂ gas pairs as compared to neat polysulfone membrane.

Abstract: Bimetallic aluminum(salen) complexes were prepared and used as catalyst for the synthesis of DPC from CO₂ and phenol in the presence of carbon tetrachloride. The bimetallic complex derived from 3,5-ditert salicylaldehyde and 1,2-cyclohexanediamine revealed more excellent activity than that obtained in the presence of other complexes and the simple Lewis acid ZnCl₂. The influence of the amount of complex and the reaction conditions including the pressure of CO₂ and the reaction temperature was also investigated.