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DFT Study of Mechanism of Extraction Reaction Between Germylene Carbene （H2Ge=C：） and Its Derivatives and ethylene oxide

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Chinese Journal of Chemical Physics 2011年第3期24卷 311-314,I0003页

作者：卢秀慧车昕李永庆王智娜济南大学化学化工学院济南250022

The mechanism of the oxide extraction reaction between singlet germylene carbene and its derivatives X2Ge=C：（X=H, F, Cl, CH3） and ethylene oxide has been investigated with B3LYP/6-311G（d,p） method. The results show that this kind of reaction has similar mechanism, the shift of 2p lone electron pair of O in ethylene oxide to the 2p unoccupied orbital of C in X2Ge=C： gives a p→p donor-acceptor bond, thereby leading to the formation of intermediate. As the p→p donor-acceptor bond continues to strengthen, that is the C-O bond continues to shorten, the intermediate generates product （P＋C2H4） via transition state. It is the substituent electronegativity that mainly affect the extraction reactions. When the substituent electronegativity is greater, the energy barrier is lower, and the reaction rate is greater.

关键词： Germylene carbene Extraction reaction ethylene oxide Potential energy surface

A mechanic insight into low-temperature catalytic combustion toward ethylene oxide over Pt-Ru/CuCeO_(x) bimetallic catalyst

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Journal of Rare Earths 2023年第6期41卷 881-888,I0003页

作者： Wenxi Zhou Kai Chen Quanli Ke Haoru Wang Xiao Chen Yufeng Liu Guokai Cui Xiaole Weng Ying Zhou Hanfeng Lu Institute of Catalytic Reaction Engineering College of Chemical EngineeringZhejiang University of TechnologyHuzhou 313200China Department of Safety and Environmental Protection Pharmaceutical CollegeJinhua PolytechnicJinhua 321017China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

The catalytic oxidation performance toward ethylene oxide(EO)and the consequent mechanism were investigated on the Pt-Ru/CuCeO_(x)bimetallic catalyst,which was prepared by a distinct method combining stepwise adsorption and subsequent *** catalytic tests show that the introduction of Ru into the Pt catalyst,so as to form Pt-Ru bimetallic active sites,can greatly increase the oxidation activity of the catalyst,as evidenced by the extremely lower full oxidation temperature(120℃)when compared with that of the Pt/CeO_(2) catalyst(160℃).The XPS spectra show that the Ru species(mainly RuO_(x))have strong interaction with the CuCeO_(x) support,which can therefore affect the electron transfer between the Pt species and the *** a result,the oxygen activation on Pt species is obviously facilitated and catalytic activity is ***,in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTs)was used to track the reaction *** is found that the catalytic oxidation process follows the MvK catalytic mechanism at low temperature and the L-H catalytic mechanism when the temperature moves to higher range.

关键词： ethylene oxide Bimetallic catalyst Catalytic oxidation Degradation pathway Mechanism Rare earths

RANDOM COPOLYMER OF PROPYLENE oxide AND ethylene oxide PREPARED BY DOUBLE METAL CYANIDE COMPLEX CATALYST

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Chinese Journal of Polymer Science 2002年第5期20卷 453-459页

作者： Yi-jun Huang Guo-rong Qi Guan-xi Chen Department of Polymer Science and Engineering, Zhejiang University Hangzhou 310027,China Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition.

关键词： propylene oxide ethylene oxide double metal cyanide complex

SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE SEPARATED AND LONG POLY(ethylene oxide) SIDE CHAIN STRUCTURES

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Chinese Journal of Polymer Science 1993年第1期11卷 67-75页

作者：邱永兴俞小洁封麟先杨士林 Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

Acryloyl terminated Poly (ethyleneoxide)macromonomers (PEO-A) with different PEO chain lengths have been prepared by deactivation of PEO alkoxide with acryloyl chloride. A new kind of amphiphilic polystyrene-g-poly (ethylene oxide)graft copolymer containing both microphase separated and PEO side chain structures has been synthesized from radical copolymerization of PEO-A macromonomer with styrene. After careful purification by a newly-developed method called 'selective dissolution', the well-defined structure of the purified copolymers was confirmed by IR, ~1H-NMR and GPC. Various experimental parameters controlling the copolymerization were studied in detail. The results indicated that the feed ratio of styrene to macromonomer(S/M) was the most important determining factor for the composition of the copolymers. A detailed 'comb- model' was proposed to describe the molecular structure of the graft copolymers. Finally, this amphiphilic graft copolymers may readily form microphase separated structures as clearly indicated by transmission electron microscopy.

关键词： PEO AIBN SIDE CHAIN STRUCTURES SYNTHESIS AND CHARACTERIZATION OF AMPHIPHILIC GRAFT COPOLYMER CONTAINING MICROPHASE SEPARATED AND LONG POLY ethylene oxide PS

Copolymerization Kinetics of ethylene oxide and Propylene oxide

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Chinese Journal of Chemical Engineering 2002年第2期10卷 218-222页

作者：尹红陈志荣 Department of Chemical Engineering Zhejiang University Hangzhou 310027

The copolymerization kinetics of ethylene oxide and propylene oxide in an atomizing-circulation reactorunder semi-continuous operation is studied which is of great importance for molecular designation. The kineticpara... 详细信息

关键词： ethylene oxide propylene oxide copolymerization kinetics mathematical model numerical optimiza-tion

UNMIXING KINETICS AND ITS MORPHOLOGY OF POLY ( ethylene oxide) WITH POLYETHERSULPHONES BLENDS

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Chinese Journal of Polymer Science 1993年第3期11卷 193-197页

作者：宋默 Guangzhou Institute of Chemistry Academia Sinica Guangzhou 510650

Unmixing kinetics in a binary polymer mixture of polyethersulphones with poly (ethylene oxide) by spinodal decomposition has been investigated with time-resolved light scattering and microscope methods. The results showed that time evolution of scattered light intensity is of an exponential growth The maximum growth rate R(qm) of phase separation has been obtained. The experimental data did not satisfy the condition that the plot of R(q)/q^2 vs q^2 should be linear For unmixing system annealing at 30℃ for three hours, its morphology manifested dish structure The experimental data of the Bragg spacing D_m can be correlated with a straight line which expresses the power-law relation, D_m=bl~α

关键词： PES WITH POLYETHERSULPHONES BLENDS ethylene oxide UNMIXING KINETICS AND ITS MORPHOLOGY OF POLY

RING OPENING COPOLYMERIZATION OF SUCCINIC ANHYDRIDE-ethylene oxide BY Al(Ⅲ) ORGANOMETALLIC CATALYSTS

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Chinese Journal of Polymer Science 1997年第3期15卷 262-272页

作者：陈仙海张一烽沈之荃 NSF Biodegradable Polymer Research Center University of Massachusetts Lowell One University Ave. Lowell MA 01854 U.S.A. Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

Ring opening copolymerization of succinic anhydride (SA) with ethylene oxide (EO)was successfully carried out by using a series of aluminum-based catalyst in 1,4-dioxane at62±2℃. The results showed that in-situ AlR_3-H_2O (R=ethyl, iso-butyl) catalysts gavehigher molecular weight (M_w～10~4), while Al(OR)_3 catalysts gave the higher alternatingcopolymer structure with slightly lower molecular weight. The in-situ AlR_3-H_2O systemshave been evaluated in more detail for the reaction which showed the optimum H_2O/Almolar ratio to be 0.5. The copolymers with different composition (F_(SA)/F_(EO)= 36/64to 45/55 mol/mol) were synthesized by using different monomer feed ratio. The melt-ing point (T_m), glass transition temperature (T_g) and enthalpy of fusion (ΔH_f) of thesecopolymers are depended on the copolymer composition and in the range of 87～102℃,-12～-18℃, and 37～66J/g, respectively. The second heating scan of DSC also in-dicated that the higher alternating copolymer was more easily recrystallized. The onsetdecomposition temperature was more than 300℃ under nitrogen and influenced by thecopolymer composition.

关键词： Succinic anhydride ethylene oxide Ring opening copolymerization Aluminum organometallic catalyst Biodegradable polymer

STUDIES OF THE CRYSTALLIZATION BEHAVIOR IN THE CRYSTALLINE/AMORPHOUS POLYMER BLENDS: POLY(ethylene oxide)/POLY(METHYL METHACRYLATE) AND POLY(ethylene oxide)/POLY(VINYL ACETATE)

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Chinese Journal of Polymer Science 1985年第3期3卷 280-288页

作者：李玄王盈康杨扬 Institute of Chemistry Academia Sinica Beijing Chemistry Department Peking University

The crystallization process of poly(ethylene oxide) (PEO)/poly(methyl methacrylate) (PMMA)and PEO/poly(vinyl acetate) (PVAc) blends has been characterized by Fourier Transform Infrared(FTIR) spectra in conjunction with Differential Scanning Calorimeter (DSC) measurements. Thecrystallinity of PEO varies consistently with PEO content in PEO/PVAc blends and the PEO/PMMAblends containing 50 wt% or less PMMA. For the PEO/PMMA blends containing 60 wt% ormore PMMA, the crystallinity of PEO decreases more than PEO content but develops with crystal-lization time. These results can be explained in terms of difference between the crystallization tem-perature (T_c) and glass transition temperature (T_g) of the blends as a function of content of amorphouscomponent.

关键词： PEO METHYL METHACRYLATE POLY STUDIES OF THE CRYSTALLIZATION BEHAVIOR IN THE CRYSTALLINE/AMORPHOUS POLYMER BLENDS VINYL ACETATE AND POLY ethylene oxide PMMA

Synthesis of Methyl 3-Hydroxypropanoate by Hydroesterification of ethylene oxide over Dicobalt Octacarbonyl Catalyst

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China Petroleum Processing & Petrochemical Technology 2012年第4期14卷 48-51页

作者： Zhang Ye Zhou Haijun Xie Xianmei Chen Xiaoping Institute of Industrial Catalysis Guangdong University of Petrochemical Technology College of Chemistry and Chemical Engineering Taiyuan University of Technology

Methyl 3-hydroxypropanoate was synthesized via hydroesterification of ethylene oxide with CO in the presence of dicobalt octacarbonyl catalyst and methanol solvent. The catalyst exhibited high catalytic activity. The effect of reaction temperature, CO pressure, methanol dosage, catalyst dosage and reaction time on catalytic reaction was investigated. The test results revealed that this reaction was greatly affected by reaction temperature, but it was not significantly affected by the CO pressure, the methanol dosage, the catalyst dosage and the reaction time. Under the optimal conditions, the conversion of ethylene oxide was equal to 92.24%, while the selectivity and yield of methyl 3-hydroxypropanoate reached 88.99% and 84.35%, respectively.

关键词： ethylene oxide methyl 3-hydroxypropanoate dicobalt octacarbonyl hydroesterification.