Methylene ethylene carbonate

The preparation of methylene ethylene carbonate and the incorporation of methylene ethylene carbonate into lithium-ion batteries as an electrolyte additive have been described (53). 

Methylene ethylene carbonate can be prepared in a good yield by mercury-catalyzed cyclization (54). Mercuric triflate (Hg(OTf)2), also called mercury(ll) trifluoromethanesulfonate, is a powerful catalyst for the cyclization of alkynyl terf-butylcarbonates giving rise to cyclic enol carbonates imder mild conditions. The S5mthesis is shovm in Figure 2.10. 

The addition of low concentrations of methylene ethylene carbonate of 1-2% to 1 M LiPF6 in 3 7 ethylene carbonate/e yl methyl carbonate improves the capacity retention of lithium-ion batteries cycled at an elevated temperature of 60°C. 

Cyclopropanation of active methylene compounds has been achieved with ethylene carbonate as the cyclopropanating agent in the presence of potassium carbonate at 150 °C and a mechanism suggested (Scheme 54).88... 

DBU DMC DMF EC EO EOS GSS ILs MBMTBP MEA MW PC PDMS PEG PEGda PEO PMPS PO PPG PPGda PTC PTHF PTMO PVP Diazabicyclo[5.4.0] -undec-7-ene Dimethylcarbonate Dimethylform amide Ethylene carbonate Ethylene oxide, oxyethylene Equation of state Gas-saturated solution Ionic liquids 2,2,-methylene-bis(4-methyl-6-tert-butylphenol) Monoethanolamine Molecular weight Propylene carbonate Polydimethylsiloxane Polyethylene glycol Poly(ethylene glycol) diacrylate Polyethylene oxide Poly(methylphenylsiloxane) Propylene oxide Poly(propylene glycol) Poly(propylene glycol) diacrylate Phase-transfer catalyst Poly(tetrahydrofuran) Polytetramethylene oxide Polyvinyl pyrrolidone... 

A polycarbonate TPE polyurethane that claims biostability is achieved through its replacement of virtually all ether or ester linkages with carbonate groups. The soft segment is composed of a polycarbonate diol formed by the condensation reaction of 1,6-hexanediol with ethylene carbonate. The polycarbonate diol is converted to a high molecular weight polyurethane by the reaction with 1,4-methylene bisphenyl diisocyanate (MDI) and 1,4-butanediol. It is reported to be resistant to environmental stress cracking as experienced with insulation on pacemaker lead wires. The polymer can be extruded, injection molded or compression-molded, and can be bonded with conventional urethane adhesives and solvents (Tables 4.4, 4.12, 4.13, and 4.14). 

Xiubin, Z., Haiyan, Z., Jin, L., Liping, L., Qiguang, W. Thermal conductivity and thermal stability enhancement of ethylene propylene diene methylene with carbon nanotube. J. Reinf. Plast. Compos. 33, 767-774 (2014)... 

Although thermal degradation of PHB in air or a nitrogen atmosphere has been well studied (69), there are few examples which show that PHB degrades in organic solvents. The molecular weight is known to decrease in propylene carbonate and ethylene carbonate at 110-140°C (67), in chloroform-methanol mixtures at room temperature (70), and in methylene chloride, chloroform, and 1,2-dichloroethane at their boiling points (68). 

Good solvent - chloroform, dioxane, ethyl acetate, ethylene carbonate, methyl acetate, methylene chloride, THF, trichloroethane ... 

Hydroxyl radical (HO") and chlorine atom-initiated oxidation of 1,3-dioxolane in N2 -O2 mixtures in the presence of NO gives ethylene carbonate and methylene glycol diformate and a photochemical mechanism has been developed to describe this... 

LSV and CV measurements indicated that methylene methanedisulfonate has a lower oxidation potential in the mixed solvents of ethylene carbonate and ethyl methyl carbonate. Further, it participates in the formation process of the CEl film. 

Materials. Poly(ethylene carbonate), was kindly supplied by PAC Polymers, Incorporated. Reagent grade methylene chloride (T p = 40 C) was obtained from J. T. B er (purity 99.8%) and used without further modification. Breathing quality air (measured to be 20.7% oxygen) was purchased from Air Products and was used for gas permeation measurements as received. 

Filins. A solution of the poly(ethylene carbonate) and methylene chloride, 2.2% polymer by weight, was mixed and filtered. Dense films of approximately 30 im thickness were cast from the QPAC-25 solution into rings onto glass plates in a methylene chloride environment. The films remained in a solvent rich environment for twelve hours. The films were then removed from the glass plate and placed under vacuum for an additional twelve hours to remove excess solvent. After this time, a test sample was placed in the permeation test system for analysis. 

DMF (> 20X), DMSO, ethylene carbonate, furfural, HMPT, methylene chloride, nitromethane, pyridine... 

The lifetime of 1,3-dioxolane with respect to oxidation by OH is about 10 h for daytime [OH] = 2.5 X 10 molecule cm". Sauer et al. (1999) have examined the OH- and Cl-initiated oxidation of 1,3-dioxolane in the presence of NO , . Major products of the OH-initiated process were ethylene carbonate (molar yield 48 7%), and methylene glycol diformate (50 14%). As shown in figure III-E-9, the cyclic species ethylene carbonate is the end product of OH abstraction from the lone CH2 group located between the two O-atoms, while methylene glycol diformate is the end product of OH abstraction from the two equivalent CH2 groups in the parent molecule. 

Place a mixture of 1 0 g. of the hydrocarbon, 10 ml. of dry methylene chloride or ethylene dichloride or syw.-tetrachloroethane, 2 5 g. of powdered anhydrous aluminium chloride and 1-2 g. of pure phthalic anhydride in a 50 ml. round-bottomed flask fitted with a short reflux condenser. Heat on a water bath for 30 minutes (or until no more hydrogen chloride fumes are evolved), and then cool in ice. Add 10 ml. of concentrated hydrochloric acid cautiously and shake the flask gently for 5 min utes. Filter oflf the solid at the pump and wash it with 10-15 ml. of cold water. Boil the resulting crude aroylbenzoic acid with 10 ml. of 2 -5N sodium carbonate solution and 0 2 g. of decolourising carbon for 5 minutes, and filter the hot solution. Cool, add about 10 g. of crushed ice and acidify... 

Chlorine reacts with saturated hydrocarbons either by substitution or by addition to form chlorinated hydrocarbons and HCl. Thus methanol or methane is chlorinated to produce CH Cl, which can be further chlorinated to form methylene chloride, chloroform, and carbon tetrachloride. Reaction of CI2 with unsaturated hydrocarbons results in the destmction of the double or triple bond. This is a very important reaction during the production of ethylene dichloride, which is an intermediate in the manufacture of vinyl chloride ... 

Two of the perfluoropolyether fluid stmctures yet to be commercialized are interesting. The first stmcture is a strictly alternating copolymer of ethylene oxide and methylene oxide, which has the longest Hquid range of any molecule containing carbon (40). The second stmcture is the perfluoromethylene oxide polyether which has low temperature Hquid properties down to —120° C ... 

PMMA is not affected by most inorganic solutions, mineral oils, animal oils, low concentrations of alcohols paraffins, olefins, amines, alkyl monohahdes and ahphatic hydrocarbons and higher esters, ie, >10 carbon atoms. However, PMMA is attacked by lower esters, eg, ethyl acetate, isopropyl acetate aromatic hydrocarbons, eg, benzene, toluene, xylene phenols, eg, cresol, carboHc acid aryl hahdes, eg, chlorobenzene, bromobenzene ahphatic acids, eg, butyric acid, acetic acid alkyl polyhaHdes, eg, ethylene dichloride, methylene chloride high concentrations of alcohols, eg, methanol, ethanol 2-propanol and high concentrations of alkahes and oxidizing agents. 

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