INDUSTRIAL A N D ENGINEERING CHEMISTRY
1662
The solutions were distilled first at atmospheric and then at reduced pressure. PEfhyImercapbethyl chloride boils at 55-58 "/ 22 and r-ethylmercaptopropyl chloiide at 69-73 "/20. The chlorides (0.5 mole) were added to a solution of sodio ethyl aeetoacetate (0.5 mole) in absolute ethanol. Hydrolysis to the ketone was effected by stirring with 5% sodium hydroxide a t room temperature. ~ - T R L A - ~ - o C T E X O I C ACID. Ethanethiol ( I mole) added ieadily topyanobutadiene ( I S ) in the presence of piperidine (6). Hydrolysis to the free acid was carried out according to Coffman ( 4 ) P-ETHYLMERCAPTO~INYL P"YL ECETO~YY. Ethanethiol (1 mole) added readily to benzoylacetylene (1 mole) (2, 8 ) in the presence of piperidine. 3-ETHYL~fE.RC.44PTOCYCLOHEXB"E; Ethanethiol added readily to eyelohexenone ( 1 ) in the presence of piperidine. LITERATURE CITED
(1) Bartlett, P. D., and Woods, C. F., J . Am. Chem. Soc., 6 2 , 2933
(1940). (2) Boden, K., Heilbron, I. M., Jones, E. R. H., and Weedon, B. C . L., J . Chem. S o c , 1946, 43.
Vol. 44, No. 7
(3) Chenicek, J. A., and Thompson, R. B. (to Universal Oil Producta Co.), U. S. Patent 2,492,335 (Dee. 27, 1949). (4) Coffman, D. D., J . A m . Chem. SOC.,57, 1982 (1935). ( 5 ) Frankel, hl.,hilosher, H. S., and Whitmore, F. C.. Ibid.,72, 81 (1950). (6) Fuson, R. C., Chem. Revs., 16, 1 (1935). (7) Gribbins, M. F. (to E. I. du P o n t de ?;emours & Co.), U. 8. Patent 2,397,960 (April 9, 1946). ( 8 ) Jones, E. R. H., Shen. T. Y.. and Whiting, M. C., J . Chem. SOC., 1950,239. (9) King, A. E., Roschen, H. L., and Irwin. 11'. H., Oil & S o a p , 10, 106 (1933). (10) Mannich, C., and Heilner, G., Ber., 55, 359 (1922). (11) Saylor, R. F., J . Chem. SOC.,1949, 2749. (12) Posner, T., Ber., 40, 4 i 8 8 (1907). (13) Snyder, H. R., Steward, J . hl.,and Myers. R . L., J . A m . Chem. SOC.,71, 1055 (1949). (14) Thompson, R. B., IKD.ESG.CHEM.,43, 1638 (1951). (15) Thompson, R . B., and C,henicek, J. 9.(to Universal Oil Produ c t s Co.), U. S. Patent 2,492,336 (Dee. 27, 1949). RECEIVED for review January 7, 1952. ACCEPTBD April 2, 1952. Presented before the Division of Agricultural and Food Chemistry a t the 121st lleeting of the AMERICAN CHEMICAL SOCIETY, Milwaukee. Wis.
Ethyl Maleopimaric Soap as Emulsifier for GR-S Polymerizations MILTON FELDON Government Laboratories, University of Akron, Akron, Ohio
F. L. McBENNOX AND R. V. LAW'RENCE Southern Regional Research Laboratory, New Orleans, La.
T
HE internal conjugated double bonds in abietic-type acids. which appear to inhibit addition polymerization, have been modified in a commercial emulsifier by disproportionation of rosin to yield a mixtuie consisting essentially of h j dio- and dehydroabietic acids (12). Another approach, adopted by the Southein Regional Research Laboiatorv in an effort to develop pine gum derivatives suitable for comniercial exploitation, is elimination of the conjugation bv a Diels-Sldw rciiction n ith
maleic anhydride (14). A derivative of this type was evaluated as an emulsifier for the polymerization of GR-S at 122" F., but the reaction rates x-ere lower than desired (8). The use of the better quality maleopimaric acid obtained by the process described by Waite, Collins, and Summers ( 1 6 ) for the preparation of the ethyl maleopimaric soap yielded a product that appeared to be satisfactory. The results obtained aith a sample of the improved product, which has the nominal formula presented herewith. are reported. PROCEDURE
0
Butadiene-styrene copolymers were prepared in 5-gallon reactors lined with glass or stainless steel and equipped nith 3-inch diameter marine-type impellers rotated at 1125 r.p.m. The charges TI ere prepared according to the following formula and then polymerized a t 122 * F (50 C ): 0 €3
I/
c- c-osa,
L
H--
C-C-OXa H I!
c,
Disodium Soap of Maleic Anhydride Addition Product of Ethy! Levopimarate (Ethyl Maleopimaric Soap)
Ingredient Parts by Weight Butadiene 71.P 28.9 Styrene b DDM (commercial a-dodecyl mercaptan! 4.3 Ethyl maleopimaric soap or Dresinate 781 Potassium persulfate 0.30 Water 180 "Pure basis. b Varied to obtain copolymers with a llooney viscosity of 50 ML-4 a t 72 f 3 % hydrocarbon conyersion. o Drainate 731 is 5 reglstered t,rade-mark for the sodium soap of disprooortionated rosin acid as manufact.ured by the riercules Powder Co.
The pH of the soap solutions was adjusted to 10.2 f 0.2 with sodium hydroxide. The extent of polymerization was calculated from the total solids contents of samples of vented latex removed from the reactor during the course of polymerization. The polymerizations were stopped nt 72 =k 3% conversion by adding
INDUSTRIAL AND ENGINEERING CHEMISTRY
July 1952
EXPERIMENTAL RESULTS
an aqueous solution of 0.20 part of hydroquinone and 0.010 part of sodium sulfite (per 100 parts of monomer) t o the latex in the reactor. The unreacted butadiene was removed from the latex by venting the latex under a moderate vacuum and the residual styrene was removed by steam distillation a t approximately 125" F. The polymers in the final latices were stabilized with 1.5% of phenyl-2-naphthylamine added on the basis of the total solids in the latex and were coagulated with sodium chloride and sulfuric acid and then dried at 155" F. in forced-draft tray-type ovens. The relative stability of the final latices was considered to be the number of milliliters of a 5% solution of sodium chloride (adjusted to a pH of 10.0 f 0.2) required t o coagulate 100 ml. of latex (adjust,ed, if necessary, to a pH of 10.0 rt 0.2).
I
Polymerizations in 5-gallon reactors with the experimental emulsifier reached 72.0% convereion in 16.4 hours as compared with a corresponding reaction time of 14.3 hours for otherwise identical charges prepared concurrently with Dresinate 731 (see Table I). Plots of the conversion versus reaction time were sigmoidal curves similar t o those obtained with Dresinate 731 and sodium tallow soap. The viscosity of latex emulsified with the ethyl maleopimaric soap was visually similar to that of the control latices with Dresinate 731, whereas the stability of the experimental latices, as determined by the salt titration test, appeared t o be somewhat greater. The increase of dilute solution viscosity with conversion for copolymers made with the ethyl maleopimaric soap was similar to that obtained for the reference polymers made with Dresinate 731 (see Figure 1). Slightly less mercaptan was required with the experimental emulsifier t o yield polymer of 50 ML-4 viscosity a t 72y0 conversion (0.76 part of D D M ) than with Dresinate 731 (0.81 part of DDM). Compounds of the experimental polymers, cured a t 292O F., exhibited stress-strain properties that were equivalent t o those of the reference stocks with Dresinate 731 prepared to the same viscosity and conversion levels, whereas the tensile strength of
ETHYL MALEO-PIMARIC SOAP (FINAL POLYMER OF 71.6% CONV, 5 2 M L - 4 , 4 % GEL)
2 .o
DRESINATE 731 (FINAL POLYMER OF 71 0 % CONV, 52 M L - 4 , 5 % GEL)
TABLE I. POLYMERIZATION DATA Reaction Time, Hours
I o ' I
I
0.0
20
40
I
I
60
80
CONVERSION, %
Figure 1.
Dilute Solution Viscosity during Polymerization
The polymers were evaluated by means of the following tests:
~
Time to 72.0% Conversion, Stability D D M , Viscosity Hours a Indexb Part ML-4 % Sodium Maleouimaric Soap 250+ 0.80 40 76.0 16.4 17.5 0.75 53 16.1 250f 69.8 15.8 0 76 51 16.8 250+ 73.3 17.2 Dresinate 731 14.7 ... 0.70 80 73.0 15.0 0.75 66 15 2 76 70.1 15.0 13.5 81 0.80 57 70.8 13.3 0.83 41 13.9 250+ 71.1 13.8 a Obtained by interpolation or extrapolation of plots of total solids content versus reaotion time. b MI. of 5% solution of sodium chloride vequired to coagulate 100 ml. of latex.
GEL AND DILUTESOLUTION VISCOSITY, by the method of Mullen and Baker (16). MOONEY VISCOSITY, by A.S.T.M. procedure (1); the results are reported as the Pminute reading obtained a t 212' F. with the large rotor (ML-4 values). MILL PROCESSING INDEX, the total of ratings for carbon black stiffening, banding time, breakdown time, mill shrinkage, and roughness. An index of 0 represents the best processibility and a value of 20 the poorest ( I S ) . EXTRUSION INDEX, by the method of Garvey, Whitlock, and Freese ( 1 0 ) . An index of 4 represents the poorest and 16 the best extrudibilit y. STRESS-STRAIN TESTS, by Office of Rubber Reserve specifica tion procedures. Tests were conducted a t (or data corrected to) 77" or 212" F. The methods are substantially in agreement with those of A.S.T.M. procedures (2,3 ) . HYSTERESIS-TEMPERATURE RISE, conducted a t 212" F. with a Goodrich flexometer by A.S.T.M. (4). FLEX LIFE, conducted a t 212' F. to a crack growth of 0.8 inch with a DeMattia flexometer (1-inch stroke) in accordance with A.S.T.M. Drocedures ( 5 ) . REBOUND, according to the procedure outlined by Fielding ( g ) , which has been proposed for acceptance by the A.S.T.M. (6). Low TEMPERATURE TEST,according to the method proposed by Gehman, Woodford, and Wilkinson (11). CRESCENT TEARTEST,according to A.S.T.M. procedure (7). The experimental and control polymers were compounded on 12 inch mills according to the following test recipe:
x
Ingredient Polymer EPC black (Wyex) Zinc oxide Sulfur Benzothian 1 disulfide (Altax) Stearic ac18
Parts by Weight 100 40 5 2 3 1.5
Final Conversion,
TABLE 11. PHYSICAL PROPERTIES~
COMBINED STYRENE,from refractive index measurements.
6
1663
Emulsifier Hydrocarbon conversion, % Combined styrene, %
Ethyl Malecpimario Soap 71.6 23.8 4 2.2 52 7.3 9.0
Dresinate 731 71 .O 23.6 5 2.1 52 5.8 10.5
%';2solution viscosity Mooney viscosity, ML-4 Mill processing index Extrusion index Stress-Strain Data a t 77' F. 1010 1020 300% modulus Ib./sq. inch 3140 Tensile strength, Ib./sq. inoh 3260 Elongation, 70 630 620 Stress-Strain Data at 212' 820 300% modulus, Ib./sq. inch Tensile Btrength, lb./sq. ineh 870 320 Elongation, % Stress-Strain Data a t 77" P. after Aging for 300% modulus, lb,/sg. inch 1910 Tensile Ftrength, lb./sq. in& 2780 Elongation, % 400 Swecial Tests 78 Hysteresis-temp. rise, ' F. 4500 Flex lifeb 0.7 Quality indexC
Commercial GR-S-10 70 =t3 23.1 7 2.2 53 0.0 10.5
1110 3570 620
F.
...
790 290
860 880 310
24 Hours a t 212O F. 2100 2070 2850 2880 380 380 71 5000 1.2
65 5000 1.5
Reboun$,$ 52 51 55 At 77 67 67 72 At 212O F. Gehman test values, minus O e. 40 37 41 Tio 49 47 48 Tim 244 253 206 Crescent tear, lb./inch polymers compounded by recipe describedjn Procedure and cured at a Test data are shown for speoimens at optlmum oure (as Judged by $gkF{noduli), except specimens for fhe rebound, Gehman low temperature, n.nd abrasion tesbs, which were cured for 30 minutes beyond optimum time b Flexures (1-inqh stroke) a t 212' F. to a cut growth of 0.8 inch. c Ratlo of flex life of test speolmen t o that of GR-S a t same hysteresis value.
1664
INDUSTRIAL AND ENGINEERING CHEMISTRY
Vol. 44,
No. 7
LITERATURE c r T m
commercial GR-S-10 was somewhat higher (Table 11). However, the stress-strain properties a t 212' F. and after aging of all these stocks were the same, within the limits of the experimental errors involved. The mill processing and extrusion characteristics of the compounds were comparable, although Dresinate 731 was slightly preferable in these respects. Ethyl maleopimaric soap also yielded polymer whose compounds exhibited a slightly higher hysteresis-temperature rise and slightly lower qualitv index (hysteresis-flex life balance) than did Dresinate 731.
Am. Soc. Testing Materials, Designation D827-47'r. Ibid., D 15-41. Ibid., D 412-41. Ibid., D 623-41T, Method A.
Ibid.,D 813-44T. Ibid., Committee D 1 1 . Ibid., D 624-48, die A. Feidon, M., private communication to Ofice of Rubber Itaaerve. Fielding, J. H . , IND.ENG.&EM., 29, 880 (1937). Garvey, B. S.,Jr., Whitlock, RI. W., and Freese, J. A., J r . , I b i d . ,
CONCLUSIOhS
34,1309 (1942).
The disodium salt of the maleic anhydride addition product of ethyl levopimarate (ethyl maleopimaric soap) yielded a reaction time of 16.4 hours to 72.0% conversion when used to emulsify 5gallon charges of GR-S a t 122"F. as compared with a corresponding value of 14.3 hours for Dresinate 731. The viscosity of latices with ethyl maleopimaric soap appeared to be similar t o that of the control latices with Dresinate 731, whereas the chemical stability of the former was greater in two instances o u t of three. Slightly less mercaptan was required with the experimental soap to yield polymer of 50 ML-4 viscosity at 72% conversion than with Dresinate 731. The physical pioperties of stocks with the experimental pol! rims M rre gtbneially coiiipara731 ble to those of similai compounds M i t h I>resin~tc
Gehman, S. D., Woodford, D. E., and Wilkinaon, C . S., J r . , Zbid., 39, 1108 (1947). Hays, J. T., Drake. A E , and Pmtt,, Y. T., Ibid., 39, 1129 (1947).
Labbe, B. G., mid Scliade, J. W;.,private coniniunioation to Office of Rubber Reserve. McKennon, F. L., Johanson, A . J . , Field, E. T . ,and Lawrenot., 1t.
V . , Ixn. ENG.CHEM.,41, 1296 (1949). ;\lullen, J. IT., and Baker, IV. 0 . . private cornriinriil.atiori t o Office of Rubber Reserve. IT'aite, E. P., Collins. U. N., and Suuiirie~s,€1 13 , Chem. IClrg , 59, N O . 2, 199-201 (1952). R E C M V Efor D review November 21, 1951. A c c ~ r ' r aMarch ~ 8, 1952. Pilot plant work reported was carried out under the sponsorship of the Ofice of Rubber Reserve, Reconstruction Finance Corporation, in conneotiorr with tlio government iynthetic ruhher program.
Vapor-Liquid Equilibria of Some Fluorinated Hvdrocarbon d
Systems J
G. H. WIIIPPI,E, E . I . du
Porit de Nerttours & Co., Wilmington, Del.
0 PUBLISHED data are available on vapor-liquid equilibria for highly fluorinated systems. Renning ( I ) has reported the existence of azeotropes between hydrofluoric acid anti CF,HCl. Horsley (6) in his tables of azeot>ropesreport,s thut one exists between CZHClFa anti cyclic C4F8 hut gives no further reference. No other references relating t,o highly fluoi,inaietl compounds have been found, A study of the vapor-liquid equilibria of five binary highly fluorinated systems was made. The result? obtained are ini,eresting from both the theoretical and the practical viewpoint, F o u r fluorinated compounds were used in this study: C'HCIF,, CC1,F2, CF2=CFCFa, and cyclic C I F ~ . Vapor-liquid equilibria were determined for each of the binary combinations of these four compounds with the exception of the system CF,=CFCF,,
