最新刊期
卷 ， 期 4 ， 1982
- 摘要：The macromolecule effect of polystyrene sulfonie acid(PSSA)on the polymeriza-tion of aerylamide (AM) has been studied．It was found that the rates of polymeriza-tion of AM were greatly increased in presence of PSSA in the polymerization system．The maximum value of the rate of polymerization of AM was obtained with the ratio of [一SO3H]：[AM] reached to 3：1．When the insoluble PSSA was used instead of the soluble one，the effeet decreased considerably．The interaction between molecules of PSSA and AM was determined by infrared spectrum．element analysis and X-ray electron spectrum．It was found that the combination form．一SO3--NH3-CO一．between sulfonic group and amide group existed．So that the infrared absoption of —NIt,moved from,3400 cm-1 to 3150 cm-1，the binding energy of electron N1s changed from 399.7 eV to 401.3 eV and the atomic ratio of N to S of products Was similar to the ratio of reagents．Based on the experimental results the mechanism of polymerization of AM in presence of PSSA is proposed．The first step is combination of AM with sulfonic group to form—CONH3+．then the AM polymerizes on the PSSA maeromolecule．The role of PSSA on the polymerization of AM is discussed．
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发布时间：2021-03-19 - 摘要：A new vinylpyridine-copolymer coordinated cluster catalyst of molybdenum-iron-sulfur has been prepared by means of solid state synthesis through multistep reaction. The structure of this catalyst has been identified as cluster structure by UV-visible and infrared spectra. The polymeric catalyst has catalystic reactivity for acetylene hydrogenation, and can be used repeatedly.
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发布时间：2021-03-19 - 摘要：A new method to study the initiation mechanism of photopolymerization by piperidyl-nitroxyl stable radical was described. The mass-spectrum was used as a means of detection. Three photo-initiation systems including a new one which has not yet been studied in detail previously were investigated.
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发布时间：2021-03-19 - 摘要：A silica supported, polymeric phosphine-palladium complexes were synthesized. The activity and stability of the catalyst for hydrogenation of olefins were investigated. The phosphine-palladium complexes anchored on silica were rather stable throughout the hydrogenation process. For monophpsphine-palladium complexes, when P/Pd=1.8, the catalyst did not show obvious decline in activity until the turnover number reached 1.4××104 cycles per site; and the activity of the diphosphino-palladium complex (P/ Pd=2.1) remained constant after turnover number of 1.6×104 cycles per site was rea-ched. Comparing our results with that of the literatures,it isobvious that the pho-sphino ligands offer good binding ability.
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发布时间：2021-03-19 - 摘要：Assumption has been made on the mechanism of the cationic emulsion polymerization of octamethylcyclotetrasiloxane (D4). The ring opening of D4, the addition polymerization and the condensation reaction take place on the surface of emulsion particle. The molecular weight, the molecular weight distribution and the number of polymer molecules are dependant on the ratio of addition reaction to condensation, the ratio is controlled by the concentration of the emulsifier on the emulsion particle.
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发布时间：2021-03-19 - 摘要：Styrene-divinylbenzene eopolymer beads of 40% crosslinking were first sulfonated with concentrated sulphuric acid and then pyrolyzed under nitrogen atmosphere in a cracking furnace. The properties pf the carbonaceous absorbent were correlated with its structures such as the surface area, the distribution of pore diameters, density, strength, etc. The surface area exceeds 800M2/g, and the porosity for the adsorption of ereatinine and uric acid is over 98%. The optimum pore diameters of the adsorbent for the adsorption ofuric acid are 6---40A. Larger diameters (160--170A). Facili-tate the diffusion of creatinine and uric acid into the pores and be adsorbed therein.
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发布时间：2021-03-19 - 摘要：A series of poly (styrene-divinylbenzene) matrixes with sapermacropores have been prepared by using polyvinyl acetate together with organic solvents (e. g. ethyl acetate, n-octyl alcohol, dioxane, touene) as porogenic agents. The average pore radius of the matrix is in the range of tens of thousands Angstroms and the pore volume is about 1ml/g (dry resin). The matrixes have been partially aininated after chloromethyla-tion to impart anion exchange capacity to the resin. Kesults of these experiments are discussed.
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发布时间：2021-03-19 - 摘要：The chain structure of 1, 2-polybutadiene prepared with molybdenum catalyst system has been studied by IR, 13C-NMR, X-ray and thermal analysis, and the method to regulate the chain structure has been investigated. It was found that some of the polar additives, e.g., allyl halides are able to regulate not only the content of 1, 2-unit in the polymer, but also its configuration and sequence distribution. Attempt has been made to estimate the sequence length of stero-isomers of 1, 2-unit by statistical theory.
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发布时间：2021-03-19 - 摘要：The active center concentration Cp, the rate constant Kp, and the activation energy of chain propagation Ep, etc. in the polymerization of propylene with complex-type TiCl2-(C2H5)2 A1C1 catalyst system were determined.The value obtained for Cp, Kp and E2 at 50℃ are 3.01 mol/mol Ti, 6.27 1/mod, sec. and 5.10 Kcal/mol respectively.The kinetic parameters are compared with the data obtained from the conventional TiCl2. 0.33 AlCL, showing that the higher activity of the complex-type catalyst over the conventional catalyst is notonly due to the higher Cp value of the former,but to a greater extent,dut to the increase of the kp value.
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发布时间：2021-03-19 - 摘要：The changes in the structure and properties of PE film during the process of weathering were studied. It was observed that the chemical reaction occuring in the polymer during short time exposure to weather could be sensitively detected and monitored by MFI (melt flow index) measurement and trace carbonyl analysis.It is concluded that the change of MFI in PE film during the initial stage of weathering is not a direct result of changes in polymer structure or rather a reflection, of cross-linking in the polymer taking place during MFI measurement,which is enhan-ced by the trace active species produced in the early hotochemical reaction.
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发布时间：2021-03-19
Research Article
- 摘要：We have investigated the synthetic methods of segmented polyether polyurethane (PEU) through polytetramethylene glycol-4, 4'-diphenyhnethane diisocyanate (PTMG-MDI) prepolymer with ethylene diamine (ED) as extender and observed that different methods of adding reagents in the two-stops solution polymerization -will result in the formation of two-phase components block copolymers with different morphology and somewhat different physical properties. Method A, adding PTMG solution to MDI then adding extender to the resulted prepolymer solution will always show better phase separation and give cystal herd domain in the size of 50--80A, while method Busual-ly give amorphous hard domain with much larger size of 1000--2000 A.
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发布时间：2021-03-19 - 摘要：Three kinds of copolymeric emulsions with concentrations up to the extent of 40 per cent were prepared by using a mixed emulsion system of ionic and nonionic emul-sifying agent in emulsion qopolymerization．Copolymeric emuLsiOIlS which had been ireated with cation and anion exchange resins are stable to long-time storage and their residual substance is eomparalble to a standard of nonionie emulsion．TG，DTG. GC-MS and pyrolysis gas chromatographic methods were used to determine the influence of variOUS copolymers．as well as the ratio of its components towards degradation rate．An order of susceptibility of degradation of these copolymers was found．These results may be of a help to finding way for synthesizing of barrier filming materials for color picture tube in aluminized screen techniques．
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发布时间：2021-03-19 - 摘要：The effect of reaction temperature on the emulsification and the polymerization rate of octamethyl cyclotetrasiloxane in the presence of dodecyl benzyl ammonium bromide emulsifier was studied. The influence of temperature on the molecular weight distribution of the polymer produced by the condensation reaction of the terminal OH-groups of polydimethylsiloxane is discussed.
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发布时间：2021-03-19 - 摘要：A new peak at 39.0 ppm in the 13C-NMR spectrum of polybutadiene (PBD) was discovered. This peak is assigned to the fouth trans peak (T4) of trans 1, 4-sequence marked with an asterisk as shown in Fig. 3 in the text.The occurrence of T4 carbon nuclei is strongly affected by their neighboring 1, 2-units. So long as both contents of trans 1, 4- and 1, 2-units reach their proper amount, the peak (T4) will appear in the 13C-NME spectrum of PBD.
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发布时间：2021-03-19 - 摘要：This article reports the photoconductive spectra of poly-N-vinylcarbazole: 2, 4, 7-trinitro-9-fluorenone (1:0.5 molar ratio) charge transfer complex (CTC) obtained with sandwich and surface cells.The effects of wavelength, field strength and polarity of the illuminated electrode on Lux-Ampere index y are discussed. Two kinds of photocarrier generation are suggested. When λ>500nm, the photocarriers were generated by light absorption of the charge transfer complex; when λ<500nm, the phptoearriers were produced by poly-N-vinylcarbazole and 2,4,7-trinitro-9-fluorenone free molecules present in the film.
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发布时间：2021-03-19
Research Bulletin
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