ELECTROCARBOXYLATION OF ORGANIC COMPOUNDS WITH CARBON DIOXIDE CATALYZED BY METALLOPORPHYRINS(Ⅱ)——ELECTROSYNTHESIS OF SOME ORGANIC COMPOUNDS WITH CO_2 CATALYZED BY CoTPP

The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO_2 are studied. The electrocarboxylation of these organic compounds with CO_2 in the presenec of catalyst can occur at more positive potential than that of no catalyst. The products of electrocarboxylation were identified by UV, IR and GC-MS. The electrocarboxylation mechanisms of different organic compounds are discussed.     

ELECTROCARBOXYLATION OF ORGANIC COMPOUNDS WITH CARBON DIOXIDE CATALYZED BY METALLOPORPHYRINS(Ⅲ)——EFFECTS OF AXIAL LIGANDS ON CATALYTIC ACTIVITY OF CoTPP

The effects of peptides,amino acids and organic bases as an axial ligand on reaction ac-tivities in the electrocarboxylation of benzyl chloride with CO_2 catalyzed by CoTPP are reported.The imidazole organic base,peptide containing —SH and amino acid containing imidazolyl en-hance the catalytic activity.The effect of imidazole amounts on the catalytic activity of CoTPP isstudied.     

ELECTROCARBOXYLATION OF ORGANIC COMPOUNDS WITH CARBON DIOXIDE CATALYTZED BY METALLOPORPHYRINS(Ⅳ)——EFFECT OF VARIOUS FACTORS ON ELECTROCARBOXYLATION

The effects of various factors on the electrocarboxylation of organic compounds withcarbon dioxide catalyzed by metalloporphyrin are studied.The optimal potential of electrocar-boxylation is -1.6 V(vs.SCE).A weak protic solvent methanol can enhance catalytic activity.Tetrabutylammonium iodide is the best one of five electrolytes.The yields and current efficienciesof electrocarboxylation are increased slowly as the concentration of catalyst increases.     

PHOTOOXIDATION OF SOME ORGANIC COMPOUNDS CATALYZED BY DECATUNGSTATES

ＰＨＯＴＯＯＸＩＤＡＴＩＯＮ ＯＦ ＳＯＭＥ ＯＲＧＡＮＩＣ ＣＯＭＰＯＵＮＤＳ ＣＡＴＡＬＹＺＥＤ ＢＹ ＤＥＣＡＴＵＮＧＳＴＡＴＥＳ￥ＢｉｎＹＵＥ；ＳｉＳａｎＺＨＵ；ＧａｏＹａｎｇＸＩＥ；ＹｉＤｏｎｇＧＵ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒ...     

STUDY ON KINETICS OF THE PHASE-TRANSFER CARBONYLATION OF BENZYL CHLORIDE CATALYZED BY DICOBALT-OCTACARBONYL

Reaction kinetics of CO_2(CO)_8-catalyzed carbonylation of benzyl chloride was studied in a liquid-liquid two-phase system(water/p-xylene). The disappearance rate of benzyl chloride is found to fit a pseudo first order kinetics law when the carbon monoxide pressure is kept constant. The observed rate constant is directly proportional to the amount of Co_2(CO)_8, PhCH_2N~+(CH_3)_3Cl~- and NaOH. It is shown that the rate-limiting step is the cleavage of the acylcobalt carbonyl [PhCH_2COCo(CO)_4] by PhCH_2N~+(CH_3)_3OH~- at the liquid-liquid interface. According to the experimental kinetic results, the reaction mechanism is suggested and the reaction rate equation is derived.     

CATALYTIC ESTERIFICATION OF CARBOXYLIC ACIDS WITH ALCOHOLS BY SULFO-POLYVINYL CHLORIDE

Polyuinyl Chloride reacted with chlorosulfonic acid to form a polymer catalyst PVC-SO3H. This polymer catalyst was found to have high activity for esterification reaction between carboxylic acids and alcohols. This paper deals with the conditions in synthesis of n-butylacetate catalyzed with PVC-SO3H. The PVC-SO3H was used as a catalyst for preparing 11 esters of acetic acid, propiofnic acid and butyric acid with the yields of 82-92%.     

CATALYTIC ESTERIFICATION OF CARBOXYLIC ACIDS WITH ALCOHOLS BY SULFO—POLYVINYL CHLORIDE

Polyvinyl Chloride reacted with chlorosulfonic acid to from a polymer catalyst PVC-SO3H.This polymer catalyst was found to have high activity for resterification reaction between carboxylic acids and alcohols.This paper deals with the conditions in synthesis of n-butlyacetate catalyzed with PVC-SO3H.The PVC-SO3H was used as a catalyst for preparing 11 esters of acetic acid,propionic acid and butyric acid with the yields of 82-92%.     

REACTION OF METHANE WITH CARBON DIOXIDE OVER SrNiAl_(11)O_(19)

合成了六铝酸盐ＳｒＮｉＡｌ１１Ｏ１９并用ＸＲＤ、ＵＶＤＲＳ、ＴＧＤＴＡ和ＴＥＭ等技术对其进行了表征。在７５０℃于ＳｒＮｉＡｌ１１Ｏ１９上进行的甲烷与二氧化碳重整反应表明，这类催化剂较Ｎｉ／ＳｒＡｌ１２Ｏ１９具有较大活性和低积碳能力，在催化反应过程中可有效地抑制Ｎｉ颗粒的增大。     

A NEW CATALYTIC PROCESS FOR THE DIRECT SYNTHESIS OF DIMETHYL CARBONATE FROM CARBON DIOXIDE AND METHANOL

ＡＮＥＷＣＡＴＡＬＹＴＩＣＰＲＯＣＥＳＳＦＯＲＴＨＥＤＩＲＥＣＴＳＹＮＴＨＥＳＩＳＯＦＤＩＭＥＴＨＹＬＣＡＲＢＯＮＡＴＥＦＲＯＭＣＡＲＢＯＮＤＩＯＸＩＤＥＡＮＤＭＥＴＨＡＮＯＬ￥ＪｉａｎｇＱｉ；ＬｉｎＱｉｈｅ；ＨｕａｎｇＺｈｏｎｇｔａｏ（Ｄｅｐａｒｔ...     

SYNTHESIS OF THE COMPLEXES OF MACROPOROUS SULFONATED RESINS WITH FERRIC CHLORIDE ANDTHEIR CATALYTIC BEHAVIOR FOR ESTERIFICATION OF ACETIC ACID WITH BUTANOL

INTRODUCTIONOnthesulfonatedresinswereirnmobilizedBronstedacidsorLewisacidstobeabletofo～polymer--supporTedsuperacidswhichhavebeenattractedmuchattentionbysyntheticchemistsbecauseoftheirpotentialofapplicationinIndustry['J.Thepolymer--supportedsuperacldcatalystshavebothactivesitesofBronstedacidsandLewisacids.Insyntheticapplicationthesespedespossesstheadvantagesoftheeaseofseparationfromthereactionsystem,lowcorrosiontotheequipmentsandreusability.Sinceseventiestherearemanypapersthatreportedp…     

SYNTHESIS OF ALCOHOLS FROM HYDROGENATION OF CARBON DIOXIDE(Ⅲ)

The effects of catalyst preparation and reaction conditions on thecatalytic activity and selectivity for hydrogenation of carbon dioxide to alcoholsover zeolite supported bimetal catalyst were studied.The results showed that:(1)ethanol easily formed on the zeolite with larger pores and methanol did onthat with smaller pores;(2)when pH value of the ion exchange solution was10,the activity reached the maximum;(3)the optimum Cu/Ru mole ratio was3;(4)the influence of reation conditions such as temperature,pressure andH_2/CO_2 mole ratio on the topic reaction was greater.     

CARBON FILMS PREPARED BY PLASMA POLYMERIZATION OF NATURAL GAS(Ⅰ)DEPOSITION AND CHARACTERIZATION OF CARBON FILMS

Plasma polymerization of natural gas has been investigated in a capacitively coupled RFdischarge apparatus.Carbon film with diamond-like properties was obtained.The structure of the filmwas characterized by IR,XPS,Raman spectroscopy and elemental analysis,etc..     

DETERMINATION OF PHOSPHORUS AND FLUORINE IN POLYMERS AND ORGANIC COMPOUNDS WITH Nd~(3+)

Percentages of P or/and F in polymers and organic compounds are found by using Nd~(3+) as pre-cipitant and subsequent titration of excess Nd~(3+) with EDTA after decomposing sample in oxygenflask. The errors of determination are for P<±0.20% and F<±0.30% except fully fluorinatedcompounds.     

STUDIES ON ORGANO-MOLYBDENUM AND TUNGSTEN COMPOUNDS(Ⅲ)——CATALYTIC POLYMERIZATION OF ACETYLENE BY M-O-C BOND-CONTAINING COMPLEXES OF Mo AND W

Catalytic polymerization of acetylene in the presence of n5-C5H5-M-(CO)3 R (M=Mo,W;R=CH3-,C2H5-) has been studied.The results show that these complexes possess catalytic activities for the polymerization and copolymerization of monosubstituted acetylene.The catalytic mechanism has been preliminarily discussed.It is suggested that the active species be metal-car-bene.In our previous publications we reported the synthesis of some new Fischer's molybdenum and tungsten-carbene complexes and catalytic activity for alkyne polymerization.The results show that the activity of Fischer's molybdenum-carbene is higher than that of tungsten.The catalytic polymerization of alkyne by M-σ-c bond-containing complexes of molybdenum and tungsten has not been reported yet in literature.Therefore,four M-σ-C bondontaining complexes of molybdenum and tungsten were synthesized by using the method reported in the literature,and catalyst polymerization of alkyne by these complexes was examined.     

CARBON FILMS PREPARED BY PLASMA POLYMERIZATION OF NATURAL GAS(Ⅱ)MECHANICAL PROPERTIES OF CARBON FILMS

Mechanical properties of carbon films deposited by plasma polymerization on different sub-strates were studied.Film hardness was measured to be approximately 20GPa.Adhesive scratch testsfound the critical load L,at which film failure occurred,of the films on silicon,glass,hard magneticrecording disc were 28,45 and 18N,respectively.No definite value was detected for the film on bear-ing steel substrate.Tribological study suggests that the friction coefficient of the films was in the rangeof 0.1—0.3.The wear rate of the carbon film was 1-2 orders of magnitude lower than that of thesubstrates.Micrographs of the wear tracks and the magnitude of the wear coefficients indicate that thelikely wear mechanism is the threebody abrasive wear.Films with stable low friction coefficient andsuperior wear resistance were obtained on silicon and steel substrates.     

POLYMERIZATION OF N,N''''-(PYROMELLITOYL)-BIS-L-LEUCINE DIACID CHLORIDE WITH HYDANTOIN DERIVATIVES BY MICROWAVE IRRADIATION

INTRODUCTIONRecently, there has been growing interest in applying microwave energy to synthetic organic chemistry[1-4],sample preparation for analysis[5], extraction of natural products from plants[6], waste treatment[7] and polymersynthesis[8-13]. The reactions involved in these applications are very fast and are completed within a short periodof time. Recently, we have used microwave irradiation for the synthesis of poly(amide-imide)s and poly(ester-imide)s[14-17].Recently more attentio…     

THE COMPATIBILITY OF BLENDS OF POLY(VINYL CHLORIDE) OR CHLORINATED POLY(VINYL CHLORIDE) WITH POLY(METHYL METHACRYLATE)

IR spectral shifts of carbonyl vibrational absorption for ethyl acetate, which acts analogically as the structural unit of poly(methyl methacrylate), in cyclohexane, chloroform, chlorinated paraffins, poly(vinyl chloride) and chlorinated poly(vinyl chloride) were measured. The results suggest that there are specific interactions between the carbonyl groups and the chlorinated hydrocarbons which could be responsible for the apparent compatibility of poly(vinyl chloride)—poly(methyl methacrylate) and chlorinated poly(vinyl chloride)—poly(methyl methacrylate) blends. Additionally, the effects of the preparation mode of blend films on phase separation and observed compatibility are discussed.     

SYNTHESIS OF POLY(ACRYLIC ACID-CO-ITACONIC ACID) IN CARBON DIOXIDE–METHANOL MIXTURES

ABSTRACT

High fluidity solvents, such as supercritical fluids, have several advantages over traditional solvents as polymerization media, such as offering a more environmentally-friendly reaction media, providing increased reaction rates, and simplifying the separation and purification of polymers. In this study, a traditional glass-ionomer polymer, poly(acrylic acid-co-itaconic acid) (PAA/IA) was synthesized by using mixtures of CO₂ and methanol as the reaction solvent and was characterized by ¹H-NMR, FT-IR, GPC, and viscometry. The mechanical and working properties of the glass-ionomer cements, prepared by mixing aqueous solutions of the polymers with Fuji II glass powder, were evaluated for compressive strength (CS), diametral tensile strength (DTS) and flexural strength (FS), as well as setting time and working time. The results showed that the polymerization reaction in CO₂/methanol mixtures was faster and had higher conversion than the polymerization reaction in water. The glass-ionomer formulations made from the copolymer prepared under SC conditions showed higher CS, comparable FS and DTS compared with those made from the same polymer prepared in water. Both of the synthesized copolymers had significantly higher CS and FS than Fuji II. The working properties of PAA/IA made in CO₂/methanol met the requirement of ANSI/ADA No. 96.     

ENVIRONMENTAL STABILITY OF THE POLYENE PREPARED BY DEHYDROCHLORINATION OF POLY(VINYL CHLORIDE)

A high-quality polyene can be obtained by exensive dehydrochlorination of poly(vinyl chloride) (PVC) in aliquid/solid two-phase system. The liquid phase is a tetrahydrofuran solution of PVC containing a small amount ofpoly(ethylene glycol) with molar mass of 400 g as a phase transfer catalys. The solid phase is potassium hydroxide particles.The structure of the polyene is polyacetylene-like and has a long conjugated C=C sequence and a narrow dispersity ofpolyene sequences according to its FT-infrared and Raman spectra. The environmental stability of the polyene was alsostudied by IR, Raman spectra and elemental analysis. Experimental results demonstrated that the polyene was susceptible toair and could be changed into a material containing high concentrations of hydroxyl and carbonyl groups. The polyenesequences were shortened and its dispersity became broader due to the effect of dioxygen.     

EMPIRICAL RULES FOR ~(31)p-NMR OF ORGANOPHOSPHORUS COMPOUNDS

The substituent effects on ~(31)P-NMR chemical shifts, are determined by five empirical rules. The proposed rules are based on that the shielding (upfield shift) of resonance nucleus is governed by the spherical symmetry of the electron cloud.