INDUSTRIAL AND ENGINEERING CHEMISTRY
SEPTEMBER, 1938
7. When the urea-formaldehyde reaction is carried out in the presence of butyl alcohol, on the basis of elemental analysis, the intermediate condensation product is shown to be a mixture of many substances but probably consists largely of: H
NCHxOCdHg I
d=O
I
NCHzOH H
8. The manufacture of urea-formaldehyde-polyhydric alcohol polybasic acid co-condensation products is described. 9. Properties and uses of a urea-formaldehyde-alkyd cocondensation product are given. 10. The effect of increasing percentages of this resin in an alkyd resin is shown graphically, both in clear and pigmented flms. 11. I n clear films the Sward hardness increases from 5 at 10 per cent urea resin-90 per cent alkyd resin to 50 a t 75 per cent urea resin-25 per cent alkyd resin.
Acknowledgment The authors wish to express appreciation to H. Reichhold for his kind permission to publish the article, and also to R. H. Kienle of the Calco Chemical Company, K. P. Monroe and P. J. Ryan of Beck, Koller & Company, Inc., B. W. Nordlander of the General Electric Company, and J. H. Shroyer of Flint Junior College for their kind suggestions and proofreading.
Literature Cited (1) Arnhold, Ann., 240, 199 (1887). (2) Ibid., 240, 200 (1887). (3) Beilstein, Handbuch der organischen Chemie, Vol. I, pp. 575-6. Berlin, Julius Springer, 1918. (4) Ibid., p. 603. (5) Ibid., pp. 603-4. (6) Ibid., p. 604. (7) Ibid., p. 605. ( 8 ) Ibid., Vol. 19, p. 2 (1934). (9) Ibid., p. 11. (IO) Ibid., p. 63. (11) Ibid., p. 64. (12)Ibid., p. 65.
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Ibid., p. 436. Ibid., p. 439. Blaise, Compt. rend., 140, 662 (1905). Cheetham and Pearce, P a i n t , Oil Chem. Reo., 99,42,44 (June 10, 1937) ; Oficial Digest Federation P a i n t & V a r n i s h Production Clubs, 8, NO. 167, 216-20 (1936). Chesne, de, Kolloid-Beihefte, 36, 387 (1932). Crump, British Patent 309,849 (1928). DelBpine, Compt. rend., 131, 745 (1900). Ibid., 131, 746 (1900). Dixon, J . Chem. SOC.,113, 238 (1918). Du Font, Compt. rend., 148, 1523 (1909). Einhorn and Hamberger, Ber., 41, 24 (1908). Ellis, “Chemistry of Synthetic Resins,” Vol. I, pp. 576-87, New York, Reinhold Pub. Co., 1935. Ellis, U. S. Patent 2,115,550 (April 26, 1938). Goldschmidt, Ber., 29, 24-38 (1896). Harnitzby and Menschutkin, Ann., 136, 127 (1865). Henry, Compt. rend., 120, 107 (1895). Hill and Walker, U. S. Patent 1,877,130 (Sept. 13, 1932). Holzer, Ber., 17,659 (1884). Hovey and Hodgins, U. S. Patent 2,109,291 (Feb. 22, 1938). John, Ibid., 1,355,834 (Oct. 19, 1920); British Patent 151,016 (1920). Lauter, U. 5. Patent 1,633,337 (June 21, 1927). Ludy, Monatsh., 10, 205 (1889); J. Chem. SOC.,56, 1059 (1889). Luther, Pungs, Griessback, and Heuck, U. 5. Patent 2,019,865 (Nov. 5, 1935). Nef, Ann., 335, 215 (1904). Ibid., 335, 216 (1904). Ramstetter, German Patent 403,645 (1922) ; J. SOC.Chem. Ind., 44, 216T (1925). Redfarn, Brit. Plastics, 5, 238 (1933). Richter, “Organic Chemistry,” 3rd ed., Vol. I, p. 587, Philadelphia, P. Blakiston’s Son & Co., 1934. Ripper, U. S. Patent 1,762,456 (June 10, 1930). Soheiber and Sandin. “Die kunstlichen Harze,” D. 309, Stuttgart. Wissenschaftliche Verlagsgesellschaft, 1929. (43) Scheibler, Trostler, and Schulz, 2. angew. Chem., 41,1305 (1928). (44) Schulz and Tollens, Ann., 289, 27 (1896). (45) Ibid., 289, 29 (1896); Ber., 27, p. 1892-4 (1894). (46) Staudinger, Ber., 59, 3019 (1926). (47) Walter and Lutwak, Kolloid Beihefte, 40, 158 (1934). (48) Walter and Oesterreich, Ibid., 34, 115 (1931). (49) Wurtz, Compt. rend., 53, 378 (1861); Ann., 120, 328 (1845). (50) Zeisel, 3rd Intern. Congr. Applied Chem., 2, 63 (1898); S.Chem. SOC.,81, 318, 115, 193 (1919); see also Kamm, “Qualitative Organic Analysis,” 2nd ed., pp. 206-8, New York, John Wiley & Sons, 1932. 28, 1938. Presented before the Div’sion of Paint and Varnish Chemistry a t the 95th Meeting of the American Chemical Society, Dallas, Texas, April 18 t o 22, 1938.
RECEIVED April
Specific Heats of Organic Vapors PAUL FUGASSI AND CHARLES E. RUDY, JR. Carnegie Institute of Technology, Pittsburgh, Pa.
The Einstein functions used in the specific heat equation of Bennewitz and Rossner are recalculated in the form of the power series, ro FIT rJ2. Use of the r constants leads to a specific heat equation of the conventional form. An example of the use of the I’ constants is given
+
+
I
I
N A COMPREHENSIVE research on the specific heats of orgsnic vapors Bennewitz and Rossner (1) found that the experimental results for a variety of nonlinear molecules containing carbon, hydrogen, and oxygen could be expressed by the equation:
where x q c = No. of valence bonds in molecule i
n = total No. of atoms in molecule Ev,, Es, = Einstein functions for a given bond with characteristic vibration frequencies, v i and 6 i
The numerical values of Y for each bond were obtained from Raman data; the values of 6 were determined empirically from the experimental data.
INDUSTRIAL AND ENGINEERING CHEMISTRY
1030
The authors (1) showed that this equation yielded results in excelIent agreement with their own experimental data and with that of other investigators. The values of the Einstein functions were listed a t 40” intervals over the temperature range, 290” to 690” K. The excellence of this formula will undoubtedly lead to its extensive use in equilibria calculations. Accordingly it was thought desirable to convert the Einstein functions into such a form that the specific heat of a given substance would be expressed as an explicit rlT function of T in the conventional power series, To
+
+
F,TZ. A majority of the values for each bond were checked and
found to be correct. Parabolic formulas were then fitted to these values by use of the “average constant” method in which the sum of the residues is made zero. The constants ro,rl,and for each frequency are given in Table I.
+ rlT + rzT2
TABLE I. CONSTANTS FOR THE SERIES, ro Bond C-C
C-0
C=C
C=O
C-H (aliphatic) C-H (aromatic) 0-H
~
ro
E
u
s
0.730 1.461 -1,140 0.730 -0,938
E6i 108 Fa X 108 3.414 -2.577 1.633 -1.414 7.254 -4.936 3.414 -2.577 3.900 -1.342
1.284
-0.938
3.900
-1.342
1,055
-1,135
5.363
-2.740
rl x io* rz x
. 7
ro
106
-1.090 -1.173 -0,432 -0,324 0,299
6.000 6.132 1.233 0.724 -1.224
-3.441 -3.550 0,935 1.308 1.658
0.171
-0,934
0,150
-0,810
rl x
Use of Table I and Equation 1 will yield (C,),=O as a function of the temperature. I n most calculations (C,), = is used. The conversion between these two specific heats can be readily made, for if it is assumed that the organic vapor obeys Berthelot’s equation of state, the following equation will be valid ( 2 ) :
where T,,p , = critical temperature and pressure, respectively
For substances whose critical data are not available, the following approximations may be introduced. The critical temperature may be obtained by the Guldberg-Guye rule: where Tb
=
T , = 1.5 Tb normal boiling temperature,
K.
The critical pressure may be estimated from the van der Waals vapor pressure equation: log p ,
=
3
(2 -
1)
The application of these two approximations will obviously lead to a constant value of 31.7 atmospheres for p,. Since a t 1 atmosphere pressure and in the given temperature range the second term in the bracket (Equation 2) is usually less than 0.2, the use of the two approximations will cause only a relatively small error in the final result. I n order to illustrate the use of Table I and Equations 1 and 2, the specific heat equation for benzene will be calculated. The structural formula for benzene shows twelve atoms and twelve valence bonds. Thus, qc = 12 i
VOL. 30, NO. 9
The valence bonds are of the following types: 3&C, 3C=C, and 6C-H. From Table I we obtain the following summations:
- 0.934 X 1 O - V + 1.284 X 10-6T2) + X fO-3T - 3.441 X 10-6T* + 6.000 1.233 X 10-aT + 0.935 x 10-‘3TZ] + 16.095 X lO-ST + 0.186 X 10-’3T2 = 6 -0.938 + 3.900 X 10-ST - 1.342 X 10-6T2) = 3{ 0.730 + 3.414 X IO-3T - 2.577 X l O - 6 T a ) = 3(--1.140 + 7.254 X lO+T - 4.936 X 10-‘T2)
6G-H = 6( 0.171 3c-C = 3(--1.090 3 c = c = 3(-0.432 cq.,Eui = -3.540 i
6C-H 3C-C 3C=C XqiEa, = (3;
-6 -
pi i
Pi
) xpiEai
-
0
=
=
-10.287
i
i (CU)=
+ 55.404 X l 0 - T - 30.591 X 10-6T2
-6.858
+ 99.20 X 10-’T
-7.857
+ 83.106 X
1 0 - 3 ~- 45.887 x - 45.70 X 10-‘T2
I O - 6 ~ 2
If for benzene we take p , = 48 atmospheres and T, = 561” K., we obtain by use of Equation 2 the final equation: (Cp),..1
(cal./mole) = 18*51 T3
- 5.87 + 99.20 X 1 O - T - 45.70 x
lO-eT2
The values calculated from this equation are given in column 2 of Table 11. Column 3 contains the values calculated by Bennewitz and Rossner for benzene by direct evaluation of the Einstein functions a t the temperatures in question. Column 4 lists the experimentally determined values cited by these authors. TABLE 11. VALUESFOR BENZENE Temp., O C. 20 74 100 107
-Calcd. Cal./MoleExptl.
~ ( C p ) pI ,
Calcd. 20.0 23.5 25.1 25.6
(1) 20.2 23.6 25.2 25.5
(1) 20.1 23.3 25.8 25.9
Temp., C. 137 167 350
-(Cp)p
Calod. 27.4 29.2 38.3
Cal./-MoleCalod. Exptl. (1) (f) 27.3 27.3
-1,
3x:i
$::
The data in the three columns are in close agreement. Equally good agreement is shown for paraffin hydrocarbons, esters, and alcohols.
Literature Cited (1) Bennewitz and Rossner, 2. physilc. Chem., 39B,126 (1938). (2) Partington and Shilling, “Specific Heats of Gases,” p, 40, New York, D. Van Nustrand Co., 1924. RECEIVED May 31, 1938.
Graphical Methods in Rayon Manufacture (Correction) As the result of a draftsman’s error, the following corrections should be made in illustrations of our article on “Graphical Methods in Rayon Manufacture” which appeared in the August, 1938, issue of INDUSTRIAL AND EKGINEERINQ CHEMISTRY:
Page 925, Figure 2: The two cases stating “1000 cc.” should be “100 cc.” Page 928, Figure 3: The five cases stating “1000 CC.” should be “100 cc.” Page 931, Figure 4. The two cases stating “1000 cc.” should be “100 cc.” JOSEPH H. KOFFOVI JAMESR. WITFIROW
