Hydrocarbon solubility

TMED, (CH3)2NCH2CH2N(CH3)2. B.p. 122 C a hygroscopic base which forms a hydrocarbon-soluble stable chelate with lithium ions and promotes enhanced reactivity of compounds of lithium, e.g. LiAlH4, UC4H9, due to enhanced kinetic basicity of the chelate. Used in polymerization catalysts, tetramethyl lead, TML 5 lead tetramethyl. 

The values of common hydrocarbon solubility parameters vary between 300 and 600 (kJ/m3) /2 Several tables are available where the solubility parameters are shown as (cal/cm ) / Jq convert these values, it is necessary to multiply by 64.69. Thus a solubility parameter value of 10 (cal/cm ) / jg equal to 646.9 (kJ/m ) / ... 

The cobalt catalyst can be introduced into the reactor in any convenient form, such as the hydrocarbon-soluble cobalt naphthenate [61789-51 -3] as it is converted in the reaction to dicobalt octacarbonyl [15226-74-17, Co2(CO)g, the precursor to cobalt hydrocarbonyl [16842-03-8] HCo(CO)4, the active catalyst species. Some of the methods used to recover cobalt values for reuse are (11) conversion to an inorganic salt soluble ia water conversion to an organic salt soluble ia water or an organic solvent treatment with aqueous acid or alkah to recover part or all of the HCo(CO)4 ia the aqueous phase and conversion to metallic cobalt by thermal or chemical means. 

Anionic polymerization of vinyl monomers can be effected with a variety of organometaUic compounds alkyllithium compounds are the most useful class (1,33—35). A variety of simple alkyllithium compounds are available commercially. Most simple alkyllithium compounds are soluble in hydrocarbon solvents such as hexane and cyclohexane and they can be prepared by reaction of the corresponding alkyl chlorides with lithium metal. Methyllithium [917-54-4] and phenyllithium [591-51-5] are available in diethyl ether and cyclohexane—ether solutions, respectively, because they are not soluble in hydrocarbon solvents vinyllithium [917-57-7] and allyllithium [3052-45-7] are also insoluble in hydrocarbon solutions and can only be prepared in ether solutions (38,39). Hydrocarbon-soluble alkyllithium initiators are used directiy to initiate polymerization of styrene and diene monomers quantitatively one unique aspect of hthium-based initiators in hydrocarbon solution is that elastomeric polydienes with high 1,4-microstmcture are obtained (1,24,33—37). Certain alkyllithium compounds can be purified by recrystallization (ethyllithium), sublimation (ethyllithium, /-butyUithium [594-19-4] isopropyllithium [2417-93-8] or distillation (j -butyUithium) (40,41). Unfortunately, / -butyUithium is noncrystaUine and too high boiling to be purified by distiUation (38). Since methyllithium and phenyllithium are crystalline soUds which are insoluble in hydrocarbon solution, they can be precipitated into these solutions and then redissolved in appropriate polar solvents (42,43). OrganometaUic compounds of other alkaU metals are insoluble in hydrocarbon solution and possess negligible vapor pressures as expected for salt-like compounds. 

Aromatic radical anions, such as lithium naphthalene or sodium naphthalene, are efficient difunctional initiators (eqs. 6,7) (3,20,64). However, the necessity of using polar solvents for their formation and use limits their utility for diene polymerization, since the unique abiUty of lithium to provide high 1,4-polydiene microstmcture is lost in polar media (1,33,34,57,63,64). Consequentiy, a significant research challenge has been to discover a hydrocarbon-soluble dilithium initiator which would initiate the polymerization of styrene and diene monomers to form monomodal a, CO-dianionic polymers at rates which are faster or comparable to the rates of polymerization, ie, to form narrow molecular weight distribution polymers (61,65,66). 

The methodology for preparation of hydrocarbon-soluble, dilithium initiators is generally based on the reaction of an aromatic divinyl precursor with two moles of butyUithium. Unfortunately, because of the tendency of organ olithium chain ends in hydrocarbon solution to associate and form electron-deficient dimeric, tetrameric, or hexameric aggregates (see Table 2) (33,38,44,67), attempts to prepare dilithium initiators in hydrocarbon media have generally resulted in the formation of insoluble, three-dimensionally associated species (34,66,68—72). These precipitates are not effective initiators because of their heterogeneous initiation reactions with monomers which tend to result in broader molecular weight distributions > 1.1)... 

Soluble analogues of these difunctional initiators have been prepared either by addition of small amounts of weakly basic additives such as triethylamine (73) or anisole (74) which have relatively minor effects on diene microstmcture (37). Another method to solubilize these initiators is to use a seeding technique, whereby small amounts of diene monomer are added to form a hydrocarbon-soluble, oligomeric dilithium-initiating species (69,75). 

The stoichiometric reaction of y -diisopropenylbenzene [3748-13-8] with two moles of j -butyUithium in the presence of triethylamine has been reported to produce a useful, hydrocarbon-soluble dilithium initiator because of the low ceiling temperature of the monomer (78,79) which is analogous in stmcture to a-methylstyrene however, other studies suggest that oligomerization occurs to form initiators with functionahties higher than two (80). 

The first successhil use of lithium metal for the preparation of a i7j -l,4-polyisoprene was aimounced in 1955 (50) however, lithium metal catalysis was quickly phased out in favor of hydrocarbon soluble organ olithium compounds. These initiators provide a homogeneous system with predictable results. Organ olithium initiators are used commercially in the production of i7j -l,4-polyisoprene, isoprene block polymers, and several other polymers. 

Zinc oxide is a common activator in mbber formulations. It reacts during vulcanization with most accelerators to form the highly active zinc salt. A preceding reaction with stearic acid forms the hydrocarbon-soluble zinc stearate and Hberates water before the onset of cross-linking (6). In cures at atmospheric pressure, such as continuous extmsions, the prereacted zinc stearate can be used to avoid the evolution of water that would otherwise lead to undesirable porosity. In these appHcations, calcium oxide is also added as a desiccant to remove water from all sources. 

The analogous reaction with ammonia leads ultimately to sihcon nitride. In the past, hydrocarbon soluble fractions of the ammonolysis were iacorrecdy referred to as sihcon diimide. This improper designation occasionally persists as of the mid-1990s. 

Methanol is frequently used to inhibit hydrate formation in natural gas so we have included information on the effects of methanol on liquid phase equilibria. Shariat, Moshfeghian, and Erbar have used a relatively new equation of state and extensive caleulations to produce interesting results on the effeet of methanol. Their starting assumptions are the gas composition in Table 2, the pipeline pressure/temperature profile in Table 3 and methanol concentrations sufficient to produce a 24°F hydrate-formation-temperature depression. Resulting phase concentrations are shown in Tables 4, 5, and 6. Methanol effects on CO2 and hydrocarbon solubility in liquid water are shown in Figures 3 and 4. 

Figure 4. Effects of methanol on predicted hydrocarbon solubility in liquid water.

A recent addition to the many examples of octahedral coordination of O (Table 14.3) is the unusual volatile, hydrocarbon-soluble, crystalline oxo-alkoxide of barium [H4Ba6(/i(i-0)(0CH2-CH2,OMe)i4l, which forms rapidly when Ba granules are reacted with Me0CH2CH20H in toluene suspension. ... 

Mono(cyclopentadienyl), or half-sandwich poly-oxo complexes are of interest as hydrocarbon-soluble models for oxide catalysts. The action of water on [Ta( j -C5Me5)(PMe3)2] yields the colourless [Ta4( j -C5Me5)407(0H)2] which has a tetranuclear butterfly core (Fig. 22.12c).( >... 

This is a linear polyester containing phthalic anhydride to ensure hydrocarbon solubility and maleic anhydride to enable copolymerisation to take place, esterified with 2-propanediol. The ester is dissolved in styrene which initially acts as the solvent and subsequently as film former when it is copolymerised with the double bond in the ester by free radical induced polymerisation. 

D. G. Peiffer, R. M. Kowalik, and R. D. Lundberg. Drag reduction with novel hydrocarbon soluble polyampholytes. Patent US 4640945, 1987. 

We have examined a number of different salts and have shown that the transition temperature can almost be altered at will (12), in many cases in line with the Hofmeister or lyotropic series (13-15J, a relationship found for many other aqueous systems such as hydrocarbon solubility and protein stability. 

Sedilo, L.P., Newlove, J.C., Peiffer, D.G., and Lundberg, R.D. "Hydrocarbon Soluble Polymer Complexes Useful as Viscosifiers in Fracturing Operations," US Patent 4,615,393(1986). 

In order to eliminate competing reaction with the solvent, a method for generating active uranium in hydrocarbon solvents was desired. Thus a hydrocarbon soluble reducing agent [(TMEDA)Li ]9 [Nap] (Nap=naphthalene) was prepared. This complex has previously been maae from 1,4-dihydro-naphthalene(llO). We have prepared this complex from lithium, naphthalene and TMEDA in a convenient reaction which is amenable to large scale synthesis. 

The report by Resa et al. on a hydrocarbon-soluble, molecular compound of monovalent zinc, namely decamethyl-dizincocene, therefore caused considerable excitement among inorganic and organometallic chemists alike.233 Organozinc compounds with direct zinc-transition metal bonds have also been reported recently, and this area of organozinc chemistry with direct metal-metal bonds will undoubtedly witness considerable growth in the near future. 

Hermann, R. B. (1971) Theory of hydrophobic bonding. II. The correlation of hydrocarbon solubility in water with solvent cavity surface area. J. Phys. Chem. 76, 2754—2758. 

Horvath, A. L. (1982) Halogenated Hydrocarbons, Solubility - Miscibility with Water. Marcel Dekker, New York. 

Brookman, G.T., Flanagan, M., Kebe, J.O. (1985) Literature Survey Hydrocarbon Solubilities and Attenuation Mechanisms, prepared for Environmental Affairs Dept, of American Petroleum Institute. API Publication No. 4414, August, 1985, Washington D.C. 

Wasik SP, Brown RL (1973) Determination of hydrocarbon solubility in seawater and the analysis of hydrocarbons in water-extracts. In Proceedings of the conference on prevention and control of oil spills. American Petroleum Institute, Washington, DC, pp 223-237... 

Figure 9. Effect of methanol on predicted hydrocarbon solubility in water phase ((A) wet hydrocarbon flash (V) wet methanol hydrocarbon flash)...

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