Methyl acetate refractive index

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. 

As pointed out by Skrabal and Schiffrer [173], the rate-determining step must be in the transition from acetal to hemiacetal because the rate coefficient for the hydrolysis of methyl ethyl formal is equal to the mean value of those for the hydrolyses of dimethyl formal and diethyl formal. Wolf and Hero Id [174] supplied more direct evidence on this matter. They found that the UV absorption bands of aldehydes slowly decrease in alcoholic solutions. This indicates that a reaction takes place. The product of the reaction immediately splits off aldehyde under the conditions of a bisulfite titration, therefore it cannot be acetal and it must be hemiacetal. Acetals are much more stable, and they are not hydrolyzed in a bisulfite titration. A quantitative kinetic study of the reaction of aldehyde with alcohol was carried out by Lauder (175] with the aid of dilatometric and refractive index measurements. He observed that hemiacetal is formed in a relatively fast reaction which is followed by a slow reaction leading to acetal. 

In this project, distinguishing properties of the 10 organic liquids should be observed (Part A) and unknowns subsequently identified (Part B) according to an SOP which I wrote for this. The properties are (1) water miscibility, (2) density, (3) viscosity, (4) refractive index, and (5) odor. The 10 organic liquids are acetone, methanol, ethanol, isopropyl alcohol, heptane, cyclohexane, toluene, methyl ethyl ketone, butanol, and ethyl acetate. 

Many cellulose derivatives form lyotropic liquid crystals in suitable solvents and several thermotropic cellulose derivatives have been reported (1-3) Cellulosic liquid crystalline systems reported prior to early 1982 have been tabulated (1). Since then, some new substituted cellulosic derivatives which form thermotropic cholesteric phases have been prepared (4), and much effort has been devoted to investigating the previously-reported systems. Anisotropic solutions of cellulose acetate and triacetate in tri-fluoroacetic acid have attracted the attention of several groups. Chiroptical properties (5,6), refractive index (7), phase boundaries (8), nuclear magnetic resonance spectra (9,10) and differential scanning calorimetry (11,12) have been reported for this system. However, trifluoroacetic acid causes degradation of cellulosic polymers this calls into question some of the physical measurements on these mesophases, because time is required for the mesophase solutions to achieve their equilibrium order. Mixtures of trifluoroacetic acid with chlorinated solvents have been employed to minimize this problem (13), and anisotropic solutions of cellulose acetate and triacetate in other solvents have been examined (14,15). The mesophase formed by (hydroxypropyl)cellulose (HPC) in water (16) is stable and easy to handle, and has thus attracted further attention (10,11,17-19), as has the thermotropic mesophase of HPC (20). Detailed studies of mesophase formation and chain rigidity for HPC in dimethyl acetamide (21) and for the benzoic acid ester of HPC in acetone and benzene (22) have been published. Anisotropic solutions of methylol cellulose in dimethyl sulfoxide (23) and of cellulose in dimethyl acetamide/ LiCl (24) were reported. Cellulose tricarbanilate in methyl ethyl ketone forms a liquid crystalline solution (25) with optical properties which are quite distinct from those of previously reported cholesteric cellulosic mesophases (26). 

Resa, J. M. Gonzalez, C. Goenaga, J. M. Iglesias, M. Density, refractive index, and speed of sound at 298.15 K and vapor-liquid equUibria at 101.3 kPa for binary mixtures of ethyl acetate + 1-pentanol and ethanol + 2-methyl-1-propanol J. Chem. Eng. Data 2004,49, 804-808... 

Copolymers present a double problem in GPC it is difficult to define an appropriate calibration method and compositional heterogeneity can alter detector responses. For these reasons quantitative studies of copolymers are rare although Janca et al. have published an extensive study of the behaviour of vinyl acetate-vinyl chloride copolymers. Elgert and Wohlschiess have used a combination of refractive index and ultraviolet detection to study compositional heterogeneity in copolymers of a-methyl styrene with butadiene. Studies of ethylene-propylene copolymers have been reported by Osawa and Inaba. ... 

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