Ethyl refraction index

Thioethers usually yield sulphonium salts when warmed with ethyl iodide and allowed to cool. The physical properties (b.p., density and refractive index) are useful for identification purposes. 

Dichloroacetic acid [79-43-6] (CI2CHCOOH), mol wt 128.94, C2H2CI2O2, is a reactive intermediate in organic synthesis. Physical properties are mp 13.9°C, bp 194°C, density 1.5634 g/mL, and refractive index 1.4658, both at 20°C. The Hquid is totally miscible in water, ethyl alcohol, and ether. Dichloroacetic acid K = 5.14 X 10 ) is a stronger acid than chloroacetic acid. Most chemical reactions are similar to those of chloroacetic acid, although both chlorine... 

Ethyl Benzoate.—This ester has not been found, so far, to occur naturally in essential oils. It has, however, been prepared by synthetic processes, for example, by condensing ethyl alcohol with benzoic acid by means of dry hydrochloric acid gas. Its odour is very similar to that of methyl benzoate (q.v.), but not quite so strong. It is an oil of specific gravity I OfilO, refractive index 1 5055, and boiling-point 213° at 745 mm. It is soluble in two volumes of 70 per cent, alcohol. 

Ethyl Cinnamate.—The cinnamic ester of ethyl alcohol is a natural constituent of a few essential oils, including camphor oil and storax. It is formed synthetically by condensing cinnamic acid and ethyl alcohol by dry hydrochloric acid gas. It has a soft and sweet odour, and is particularly suitable for blending in soap perfumes. It is an oil at ordinary temperatures, melting at 12°, and boiling at 271°. Its specific gravity is 1 0546, and its refractive index 1 5590. 

Ethyl Salicylate.—The ethyl ester of salicylic acid resembles the lower homologue, methyl salicylate, in its general characters and perfume value. It is an oil of specific gravity 1 1372, refractive index 1-52338, and optically inactive. It boils at 234°. It solidifies at low temperatures, and melts at 1-3°. 

The free oil can be determined by an ion exchange HPLC technique. A solution of the sample in ethyl alcohol is analysed by high-performance ion exchange chromatography using a specially prepared ion exchange resin stationary phase, ethanol mobile phase, and differential refractive index detection. 

If the mixture to be separated contains fairly polar materials, the silica may need to be deactivated by a more polar solvent such as ethyl acetate, propanol or even methanol. As already discussed, polar solutes are avidly adsorbed by silica gel and thus the optimum concentration is likely to be low, e.g. l-4%v/v and consequently, a little difficult to control in a reproducible manner. Ethyl acetate is the most useful moderator as it is significantly less polar than propanol or methanol and thus, more controllable, but unfortunately adsorbs in the UV range and can only be used in the mobile phase at concentrations up to about 5%v/v. Above this concentration the mobile phase may be opaque to the detector and thus, the solutes will not be discernible against the background adsorption of the mobile phase. If a detector such as the refractive index detector is employed then there is no restriction on the concentration of the moderator. Propanol and methanol are transparent in the UV so their presence does not effect the performance of a UV detector. However, their polarity is much greater than that of ethyl acetate and thus, the adjustment of the optimum moderator concentration is more difficult and not easy to reproduce accurately. For more polar mixtures it is better to explore the possibility of a reverse phase (which will be discussed shortly) than attempt to utilize silica gel out of the range of solutes for which it is appropriate. 

It has also been possible, in various ways which cannot be detailed here, to prepare both the keto- and enol-forms of ethyl acetoacetate in the pure state (Knorr, K. H. Meyer). Their physical constants are altogether different. The refractive index, for example, is 1-4225 (D10 ) for the keto-form and 1-4480 for the enol-form. From determinations of the refractive indices of equilibrium mixtures the content of both forms can be calculated by interpolation (Knorr, 1911), and these results have been confirmed spectroscopically (Hantzsch, 1910). 

In Eq. (88), dn0/dl expresses how the refractive index % of the binary solvent alone varies with its composition expressed as volume fraction 4>y of liquid-1. Clearly, if liquids 1 and 3 are iso-refractive or nearly so, then M = M2, that is, a LS experiment will yield the true molecular weight irrespective of the composition of the mixed solvent. This situation is exemplified133) by the system polystyrene -ethyl-acetate (l)-ethanol (3) for which the molecular weight in mixed solvents of different 0i is the same as that obtained in pure ethylacetate (Fig. 40). The values of dn /d0j for the mixed solvents are only of the very small order of ca. 0.01, whilst the values of dn/dc for the polymer solutions are large (ca. 0.22 ml/g). 

Fig. 56. Dependence of specific refractive index increment on conversion of monomers to polymer for a styrene/acrylonitrile/methyl methacrylate terpolymer in methyl ethyl ketone at 20 °C and 436 nm. (a) - partial azeotrope, (b) terpolymer with composition distribution163 ...

Aminabhavi, T.M. and Banerjee, K. Density, viscosity, refractive index, and speed of sound in binary mixtures of acrylonitrile with methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, and 3-methylbutyl-2-acetate in the temperature interval (298.15-308.15) K, / Chem. Eng. Data, 43(4) 514-518, 1998b. 

Figure 8. Gel filtration of ethylated (/ -0-4)-(/ -/ )-DHP 16. Solid line Ethylated (/ -0-4)-(/ -/ )-DHP 16 after removal of low molecular weight fractions. The column was calibrated with (/ -0-4)-(/ -/ ) lignin substructure model trimer 6 (molecular weight 642) /3-0-4 lignin model dimer 1 (molecular weight 348) and polystyrenes of molecular weight 9000, 4000 (void), 2200 (indicated by A). Column Sephadex LH-20, 1.1 x 48 cm. Eluent DMF, 13.5-14.4 ml/hr. Detector Refractive index detector RI-2 (Japan Analytical Industry Co., Ltd.).

Ionic liquids are a class of solvents and they are the subject of keen research interest in chemistry (Freemantle, 1998). Hydrophobic ionic liquids with low melting points (from -30°C to ambient temperature) have been synthesized and investigated, based on 1,3-dialkyl imidazolium cations and hydrophobic anions. Other imidazolium molten salts with hydrophilic anions and thus water-soluble are also of interest. NMR and elemental analysis have characterized the molten salts. Their density, melting point, viscosity, conductivity, refractive index, electrochemical window, thermal stability, and miscibility with water and organic solvents were determined. The influence of the alkyl substituents in 1,2, 3, and 4(5)-positions on the imidazolium cation on these properties has been scrutinized. Viscosities as low as 35 cP (for l-ethyl-3-methylimi-dazolium bis((trifluoromethyl)sulfonyl)amide (bis(triflyl)amide) and trifluoroacetate) and conductivities as high as 9.6 mS/cm were obtained. Photophysical probe studies were carried out to establish more precisely the solvent properties of l-ethyl-3-methyl-imidazolium bis((trifluoromethyl)sulfonyl)amide. The hydrophobic molten salts are promising solvents for electrochemical, photovoltaic, and synthetic applications (Bon-hote et al., 1996). 

The most widely used acrylic plastics are PMMA (Lucite) or copolymers of methyl methacrylate with small amounts (2 to 18%) of methyl or ethyl acrylate (Plexiglas). These commercial products, which are available as sheets and as molding powders, have a specific gravity of about 1.2, a heat deflection temperature of about 95 C, a refractive index of about 1.5, and a water absorption of 0.2%. PMMA is more resistant to impact than PS or glass, but its scratch resistance is inferior to that of glass,... 

Research Focus Synthesis of high refractive index monomers of mono- and dimethacry-lates containing thiophene and disulfide for crosslinking with 2-hydroxy-ethyl methacrylate. 

High refractive index optical lenses were prepared by Your et al. (1) consisting of trifluoroethyl methacrylate, butyl acrylate, phenyl ethyl acrylate, and ethylene glycol dimethacrylate. 

A 100-ml autoclave was charged with ethyl acetate (24 parts), 1,4-dioxene (20 parts), and t-bu ty 1 pcrox pi val ate (0.3 parts) and then treated with chlorotrifluoroethylene (31 parts) and polymerized at 55°C for 13 hours. The precipitated polymer was isolated and dissolved in 150 ml of tetrahydrofuran (THF) and then precipitated in methanol, the process being repeated twice. Thirty-five grams of product were isolated having a Tg of 154°C and an Mn of28,000 Da with a refractive index of 1.459. The material was soluble in most organic solvents and formed transparent films. 

We have also synthesized bis(2-azidoethyl) adipate (BAEA) by the reaction of bis(2-chloro ethyl) adipate (BCEA) and sodium azide in ethanol medium and characterized the product for solubility, density, refractive index, impact sensitivity, thermal behavior and moisture content [171]. These properties suggest that a part of non-energetic plasticizers, that is, , DEP, DOP etc. can be replaced by BAEA in propellant formulations thereby resulting in increase in their fsp. 

NMR mass chromatogram corresponds to a one-dimensional UV or refractive index chromatogram. The second peak consists of methyl methacrylate and ethyl acrylate, which is evident from the different chemical shifts provided from the on-line experiment. A clear differentiation is available from the chemical shift of the methyl group of both compounds. The chemical shift at 1.9 ppm indicates the methyl group at the double bond of methyl methacrylate, whereas the signal at 1.22 ppm is from the terminal methyl group of ethyl acrylate. Thus, the second dimension of the SFC-NMR run, provided by the H chemical shifts, enables the separation of co-eluting compounds. 

A 20% solution of sodium / -nitrophenolate (p-NphNa) from collector 7 (see the previous diagram) is pressed by compressed nitrogen into reactor 1. Reactor 1 is also loaded with OP-7 catalyst out of batch box 3. The contents of the reactor are heated with water sent into coil 2. After that the hot water is switched off and the coil is filled with cold water to withdraw the heat of the reaction. Reactor 1 receives ethyl monochloride from batch box 4. 1 hour after ethyl monochloride begins to flow out of batch box 5 into reactor 1, it is supplemented with an 18% soda solution to support the neutral medium in the reactor. The synthesis takes 5 hours. The end of the reaction is determined by the analysis of thiophene by the refraction index (nD20 = 1.47-1.50). 

Ethyl Alcohol occurs as a clear, colorless, mobile liquid. It is miscible with water, with ether, and with chloroform. It boils at about 78° and is flammable. Its refractive index at 20° is about 1.364. 

Given in the literature are vapor pressure data for acetaldehyde and its aqueous solutions (1—3) vapor—liquid equilibria data for acetaldehyde—ethylene oxide [75-21-8] (1), acetaldehyde—methanol [67-56-1] (4), sulfur dioxide [7446-09-5]— acetaldehyde—water (5), acetaldehyde—water—methanol (6) the azeotropes of acetaldehyde—butane [106-97-8] and acetaldehyde—ethyl ether (7) solubility data for acetaldehyde—water—methane [74-82-8] (8), acetaldehyde—methane (9) densities and refractive indexes of acetaldehyde for temperatures 0—20°C (2) compressibility and viscosity at high pressure (10) thermodynamic data (11—13) pressure—enthalpy diagram for acetaldehyde (14) specific gravities of acetaldehyde—paraldehyde and acetaldehyde—acetaldol mixtures at 20/20°C vs composition (7) boiling point vs composition of acetaldehyde—water at 101.3 kPa (1 atm) and integral heat of solution of acetaldehyde in water at 11°C (7). 

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