The Infrared and Ultraviolet Absorption Spectra of Two Isomers of

The freezing point of di4-butyl ketone (Table. 11) was obtained bv means of a platinum resist-. 1.320 54.7. &ce thermometer *according to * the proced...
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H. F. GRAY,JR., R. S. RA~MUSENAND D. D.TUNNICLIFF

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compounds, and were as follows: For di-4-butyl ketone, tc = W0, Pc = 30 atm.; for di-i-butylcarbinol, tc = 3IOo, Pc = 35 atm. Table I1 records other properties measured. TABLE 11 Property

VARIOUS PHYSICAL PROPERTIES Di-i-butyl Temp,, OC. ketone

Density,g./ml. 20.00 * 0.01 (vac.) 40.00 * .02

.02

0.80600 0.8096g .78995 .79522 .77379 .77990

20.00 .01 20.00 * .01 20.00 * .01

1.41225 1.42314 1.41751 1.42836 1.41012 1.42096

60.00

f

Refractive index,nn np

1zc

Di-i-butylcarbinol

f

Specific dispersion, X lO'20.OO

lzF

*

.01

91.7 1.320

(L

Viscosity, centipoises

0 20 30 40

0.903

Sol., water in cpd., %w. 23 solubility in water,o/ow. 25 Freezing point,

"C.

91.4 54.7 13.9

.765

7.87

.665

4.76

-4

1.0

.043 -46.04 * 0.01

0.03

The densities of the liquids are the averages of determinations which did not differ more than 1.5 X from the mean. They were measured by means of 15 ml. Bingham pyctlometers. Special care was taken in all manipulations to

VOl. 69

avoid contamination of the samples. The accuracy is estimated to be *3 X The refractive indices sate the averages of determinations carried out with a B a d and Lomb precision refractometer and a Pulfrich refractometer. The instruments were checked by means of standard liquids of the Bureau of Standards and the deviations from the mean did not exceed 2 X lod. The accuracy is estimated to be *4 x 10". The viscosities were determined by means of a Zeitfuchs viscosimeter, with an estimated accuracy of 2 X lovacentipoises. The saturation equilibria di-i-butyl ketonewater (Table 11) were established by ultraviolet analysis and the Fischer method. The freezing point of di4-butyl ketone (Table 11) was obtained bv means of a platinum resist&ce thermometer *according to * the procedure described by Glasgow.ll The value given is that calculated for zero impurity. Summary The following properties of di-i-butyl ketone (2,6-dimethyl-4-heptanone) and di-i-butylcarbinol (2,6-dimethyl-4-heptanol) have been determined : vapor pressure, heat of vaporization, density of the liquid, refractive index, specific dispersion, viscosity, and the saturation equilibria with water. The freezing point of di-i-butyl ketone has also been measured. (11) Glasgow, Streiff and Rossini, J . Res. N o f l . Bztr..Sfondords, 86, 355 (1945).

EMERYVILLE, CALIF.

RECEIVED FEBRUARY 3,1947

[ CONTRIsUTION FROM THE SHELL DEVELOPMENT COMPANY]

The Infrared and Ultraviolet Absorption Spectra of Two Isomers of Mesityl Oxide BY H. F. GRAY,JR., R.S. RASMUSSEN AND D. D. TUNNICLIFF The infrared absorption bands from 2 to 1 5 of ~ the low- and high-boiling isomers of mesityl oxide' as determined on the pure liquids in 0.02 mm. cells, are as follows. TABLE I B. p., 121.5'

3.25 3.37 5.83 6.06 6.95 7.02 cu. 7.1 cu. 7.25 7.36

(50)

(70) (90) (60)

(70) (70) (60) (60) (80) 7.54 (60) 7.88 (40)

(1) F. H.

B. p., 130°

3.00 (5) 3.37 (70) 5.36 (5) 5.57 (5) 5.91 (90) 6.14(100) 6.91 (90) ca. 7.0 (80) 7.23 (90) 7.35 (90) 7.90 (20)

Stmss, J. M. Monger and € de I . V. Fiiach: paper I,

THISJOURNAL, 67, 1627 (1W7).

8.20 (80) 8.62 (90) 9.53 (20) 10.39 (10) 11.16 (100) 11.79 (5) 12-58 (10)

8.20 (90) 8.56 (So)

9.33 9.82 10.35 12.16

(30) (40) (90) (70)

Wave lengths are in p ; intensities are indicated as per cent. absorption a t the maximurn. The prevalent isomer, which has the comnonly accepted conjugated stxwture slnd according to the results of the preceding article is the highboiling one, exhibits the strong.cF=o band a t 6.14p, greatly shifted from the normal unconjugated position at 5 . 8 3 j ~ . Also, ~ the arrangement ('2) E . g., see spectra given by R. B. Barnes, R. C. Gore, U.LiddP and V. 2. Williams, "Infra-red Spectrgcopy,"Reinhdd Publishing Co.,New York, N . Y., 1944; H. W. Thompson and P. Torkington. J . Chrrn. Soc., 640 (1945).

July, 1947

TEMPERATURE DEPENDENCE OF OSMOTIC PRESSURE OF

POLYVINYL CHLORIDE

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of s u b s t i t ~ t sabout the double-bonded carbons of other compounds containing the conjugated (RpC.rCMR) is r4&d in the strong 12.16~~system C==C-C=O. The low-boiling isamer band.* The structure of the low boiling isomer shows only the singk band near 2900 A. (molar is clearly indicated to be the unconjugated form, extinction coefficient a. 77 liters/mole cm., 4-methyl-Ppenten-2-one, by the fact that the spectrum of i-octane solution) characteristic of C=O ban& appears at the normal unconjugated simple unconjugated ketones. ketone position, 5.83p, and that the strong band The intensity of the 2310 A. band made,it a in the 10 to 15p region occurs a t 11.16p, the logical choice for quantitative analyses for the position associated with the R2C=CH2 con- conjugated isomer, and itwas so used in the work figuratiom8 This result is in agreement with the described in the preceding article.' The infrared Raman work of Dupont and Menut* on a mixture spectra, which as obtained for this work were not of the isomers, the presence of a 1716 cm.-l line suitable for use in precise quantitative analyses, associated with unconjugated C=O indicating an were nevertheless used analytically to get approxiunconjugated form. mate ratios of conjugated to unconjugated isoIn agreement with chemical evidence referred mers, and to check for the presence of extraneous to in the preceding article, no appreciable con- compounds (water, acetone, hydration products, centration of enol form was present as indicated etc.). by the weakness of hydroxyl group absorption summary near 3 . 0 ~ . The ultraviolet absorption spectra (2100 to 1. The infrared (2 to 15p) and ultraviolet 5000 8.)independently lead td the same con- (5000 to 2100 A*.) absorption spectra of two isoclusion. The high-boiling isomer exhibits bands mers of mesityl oxide are reported. a t 2310 and 3290 8.(molar extinction coefficients 2. The spectra of the high-boiling isomer show 1.20 X lo4 and 40.5 liters/mole cm. respectively; it to have the commonly accepted conjugated spectra of i-octane solutions). These bands are structure, 4-methyl-3-penten-2-one.Those of the closely similar in position and intensity to those low-boiling isomer clearly indicate it to be 4(3) R.S.Rasmussen and R. R . Brattain, J . Chcm. Phys., 10, 120 methyl-4-penten-2-one. (1947).

(4) G.Dupont and M. L. Menut, Bull. sot. chim., 6, 1215 (1939).

EMERYVILLE, CALIF.

RECEIVED FEBRUARY 3,1947

[CONTRIBUTION FROM THE DEPARTMENT OF CHEMISTRY, POLYTECHNIC INSTITUTE OF BROOKLYN]

The Temperature Dependence of the Osmotic Pressure of Polyvinyl Chloride Solutions B Y PAUL D O T YAND ~

ELIMISHUCK3

thetical lattice used in deriving equation (1). More detailed considerations,4,6,7 however, show that p depends in a complicated manner on th& concentration of polymer segments in the immeAX = RT[ln (1 - v2) v2(1 - I/%) pv2] (1) diate vicinity of a given polymer segment; this The volume fraction of polymer is denoted by in turn depends on the flexibility of the polymer; vz and the ratio of the volume of the polymer the amount of branching and on the concentramolecule to the solvent molecule by x . The tion. Estimates from experimental measurequantity fi is of critical importance. Huggins4 ments on rubber-benzenea and rubber-tolueneg suggested that i t be considered as the sum of a and from the theory place the value of /3 in dilute temperature independent term, @, corresponding solutions in the range 0.3 to 0.4 for non-polar to the entropy contribution and a temperature polymers. dependent term a/RT, corresponding to the heat The quantity a is approximately equal to the contribution, heat of dilution, @I, divided by f. (This apTo a first approximation @ is equal to the re- proximation would be an exact equality if vz were ciprocal of the coordination number of the hypo- independent of temperature.) For nun-polar (1) Presented et the Polymer Forum, 109th meeting of the Ameripolymers in dilute solution the value of a should can Chemicpl Society, Atlantic City, N. J., April 9, 1946. be in the range of 0 to about 100 cal./mole. For (2) Present address: Department of Colloid Science, The Uni-

Statistical thermodynamic t h e o r i e ~ of. ~ *poly~ mer solutions give for the free energy of Cwution AF,, the following expression

+

+

versity, Cambridge, England. (3) Taken in part from a thesis ptesented in partial ful6lment for the degree of Master of Science, Polytechnie Institute of Brooklyn, June, 1946. (4) Huggins. J . Chcm. Phys., 0, 440 (1941); Phys. Chem., 46, 151 (1942); Ann. N. Y.Acad. SEI.,48, 1 (1942); 44,431 (1943). ( 5 ) Flory, J . Chcm. Phys., 9,668 (1941); 10, 61 (1942).

(6) Flory,ibid., 18,453(1946). In this paper there is a review of all measurements which allow an estimation of the values-of B snd a in dilute solution. (7) Zimm, ibid , 14,164 (1946). ( 8 ) Gee and Treloar, Trans. Forodoy Soc., 88, 147 (1942). (9) Meyer, Wolff and Boissonnas, H u h . Chim. Acto, P8, 430 ( 1940).