Artificial Bristles from Proteins T. L. MCMEEKIN, T. S. REID, R. C. WARNER, Eastern Ragionnl
Re-rch
AND R. W. JACKSON Laboratory, U . S. Deportment of Agri~ultt're,Philadelphk, Pa.
M .
ETHODSfor theconA method ia d-sihed for produoing ooarse fibers from qualilyof thecasein, howev versionof amorphous is of importanoe for mski casein hy extruding a heated mixture of Easein and water fiber. To be suitable for t pmteins into fibershave long through a suitable die. When the fiber is stretched and been known. In 1898 Millar produotion of fiber, a cas( hardened, under tension, with quinone, a bristle material (3)prepared protein fibers hy should be free from lack isohtained,whi~hi%~*gte%ledin~~taintypeRofhrushea. extruding heated proteinnnd other whey constituen water mixtures into air. be soluble in borax aolutir snd yield an squeous extiset having B pH near the iswlect A few years ister Todtenhsupt (6)made cMwBin fibers by exk i n t 014.7. truding an alksline solution of casein into an acid bath. %cent In making casein fiber, 40-100 mesh commercial acid-preci irnprovemsnta in the latter prohave resulted in the eamitated casein containing approximstely 9% moisture is mix mercial development of e, textile fiber from cauein. Early in the with 70% of its weight of water, nnd the mixture is allowed development of protein fibera, it WBS found that the durability of the fiber a'as markedly incressed by treatment with formaldehyde stand for an hour. The hydrated casein is plaoed in a discontin ous pres of the cylinder type with 8 volume of 370 eo. (Figure and other tanning axents. These subskancer decrease water ahand 2) and heated slowly to about 95' C. to remove air and form eorption and hscterinl decomposition of protein fibers and make plastio mass. Fibers are formed hy forcing the heated casei them more flexible. Wster absorption of the treated protein water mixture through B die with holes of 8 suitable diamet$ fiber is not completely eliminated, however, and 1098 in streneh and shspe of the fibersin the presence of water limits their use. usually fmm 0.3 to 0.6 mm. A finely woven stanlus steel sere, or breaker plate is placed in back of the die to m i s t in the remw The present shortage of pig bristles and other coarse animal of air and foreign material from the casein before the fiber hair, such ar horsehair, suggested the development of a prolein formed. To minimize sticking, the fibers are passed rspidlg I fiber hnvinq the niae and properties of these nstuml hairs. In the means of rotst,ingdrums through a solution, at 8 pH of about 4. following method lor preparing suoh fiber,heated isoeleotrie pmcontaining 2% formaldehyde, 0.1% naphthalene sulfonate, BI k i n mixed with .water is extruded into air; it is then stretched and hardened, under tension, with quinone *lone or quinone fol10% sodium sulfate. Tile fibers %re collected on B suitable reg lowed by formaldehyde. PRPPARATION OF FIBUIS
A number of protei-, including cssein, soybean. gelatin, zein, edestin. srsehin. and afutenin. have been mnverted into fibem bv
Several commercisl acid-precipitated oaseins were found to be suitable for fiber eXtN3iOn. Purification of the better oommorcbl w i n s did not materially impmve the quality of the fiber. The Figure 1 (Below). P m a and Aoee~sory PCuipment for Spinning Casein Fibem Figure 2 (Right). Close-up View of Fiheo. Pornxed hy Extruaion of Heated Casein-Water Mixture throuph the Four-Hole Die into Air
Vol. 31, No. 7
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
Figuze 3. Motor-Driwm Machine for Stretrhing Sheir, Casein Fiber during Hardening with Quinone
as shown in Figure 1. Fiber can ~ 1 9 0be made by extruding casein mixed with only 37% of its weight of water. In this ease sticking is so much reduced that the fibers &re extruded directly in air without the bath. The extruded fiber. in the form of B skein of continuous 61s-
inoresse in the degree of stretching reduces flexibility. Cons+ quently. stretching is not oarriwf to the greatest possible extent in making bristlelike easeio fibers. Instesd the fibers are stretched only to twice their original length in the quinone bath in order to obtain the highest strength c o d t e n t with greatest flexibility Stretching also increaeea the wet strength and slightly d e c r e w water absorption. This treatment resulte in 8 casein bristle with a dry strength of 0.74.8 gram per denier under standard conditions and a wet strength of 0.34.4gmm per denier sfter imrncrmon in water for 4 hours at 70° F. (Table I). PROPER?IES AND USES OF ARTIFICIAL BRISTLES
T h e stretobed and quinone-hardened oasein fibers are oylindried (Figure 5 ) and black. Figure 6 shows mmples of experimental brushes made with easein bristle fiber. The stiffnw of the fiber varies with the diameter. Fibers with B diameter of 0.6 mm. (3312 denier) are quite stiff; fibers with a dindeter of 0.2 mm. (368 denier) are soft and pliable. Experimental paint brushes d e with this fiber have been prepared in considerable numbers. Since heating hardened casein fibers above 100" C. for several bourn produces brittleness, ordinary methods of setting natural bristles such as that involving the vulcanization of rubber for several hours st 140" are unsuited for artificial bristles made from casein. This difficulty has been overcome by vulesnizing with ntbber s t lower temperatures and ~ 1 9 0by using a setting ma-
@
0
0 I
0
200
100 P.rc.nl
Figure 4.
.
I
SlreISh
Influence of Degree of Stretohing on Pmperties of Fiber (300-1000 denier)
.t-Be ..
A and 6. d v
-sthhi of fibsr xtth ...t," ...... .C, m i l e.amnth '. .~ ..-. ~
~
Figure 5.
Photomicrograph of a Cmas Section of Casein R.l'..L.
(V
111
July, 1945
M
I N D U S T R I A L AND E N G I N E E R I N G CHEMISTRY
Casein bristles are stable in air under ordinary conditioas 80 have been kept for two yesm without deterioration. Even afh long heating at Bo" C., the physical properties of the fiber we chan& only slightly when subsequently conditioned at roo tempersture.
1 . 1
TABLE 11.
I
COMPnWSON OP CASEIN BrUsTLEs WITH NATUW
BRUTLEB
T s ~ i l eStrength, G./Danisr s6qr.h.. 70
Mltsrid C-in brblls Pq hiiatld
F.
0.7-0.8 1.*1.2 1.2-1.4
Nomahlir
Singla knot 0.8-O.Q 0.8-0.9 0.%1.0
.r";r%",
in W.UI 4 hi. in a i t s r [ 2 2 - 2 V C. 0.3(1-0.4S 18.6 0.9-1.2 20 l.&l.3 21
DISCUSSION
The batch prmeas described for the production of&n brise many purposes. For l a r g s a d e economic pr duotion, however, a continuous prows would be highly advs tageous, and it hss been found that tbe fiber e m be extruded wii B commeroidly svsilsble screw-type extruder. The prod &bed bere, involving hardening for 24 bourn at mom temper ture, pmduces a fiber oontaining approximately 10% quinon Thk amount of quinone in required to make the fiber durable ar resistsnt tu water. The inhenee of temperature on the rate uptake of quinone is &own in Figure 7. In order to obtain a proximately 10% quinone in the fiber in 10 minutes, it neoeasary to um a temperature of Bo' C. IS adequate for
I
I
Figure 6. Casein Bristle and Experimental Brushes M a d e from Artificial Fibv tend, made of urea-formaldehyde and dkyd typea of synthetic resin, that hardens at 80' C. These paint brushes, although made of untapered bristles, hsve gmd paineearrying capacity, make smootb films, snd have gwd wear resistance. The bristles are resistant to oila and fat nolvente, but noften when allowed to stand in water. Although the dry tensile strength 01 the casein bristles is not no great 88 that of natunrl bristles, the strength is adequate for most brushes not subjsot to wetting with water. In wster the casein bristles absorb about 18% water, become safi, and have a tensile strength of only about half their dry tensile strength; thin makes them unsuited for use in water. Table I1 compares easein bristles with natural bristlw.
Erpt. No.
Dsniar
40
214
67 104
Tensile Strength. G./Daniar* 70a F. 4 hours in water
T i m e in
Minutes
06% r.h..
0.84 0.78
o.as
..
0.48 0.33
470
0.86
0.44 0.42 0.37
426
0.76 0.71 0.70 0.80
0.70
0.47 0.40 0.48
Figure 7. Influence uf Temperatere on Uptake of Quinone (Fiber Diameter 0.3-0.5 Mm. or 828-2301 Denier) The simultaneous stretching and hardening of the fiber in relatively short period requires further investigation. To increa the tensile strength of the fibers, the stretch must be applied at definite time during hardening. Considerable stretch c ~ be n B plied to the fiber 89 it emerges from the orifice of the extrud while it is in the air and still st an elevsted temperature. Ho? ever, no added StrenKth is given the fiber by the maximu stretch that e m be applied in this manner. It is necessary have a oertsin minimum degree of hardening in order to ineres the strength by st,retching. If the hsrdeninE b89 Dmaressed tc far, however, the fiber can be stretched eomp&ativky ittie befo
688
INDUSTRIAL A N D E N G I N E E R I N G C H E M I S T R Y
i t breaks. There is thus an optimum amount of hardening for permitting the maximum effective stretch to be applied. This was shown by an experiment in which the maximum degree of stretch that could be applied to the fibers was determined a t 5minute intervals aFter immersion in a quinone solution under various conditions. The maximum extension of about 300% was attained in 30 to 45 minutes at 2 2 O , 15 to 35 minutes a t 35O, and 10 minutes at 50" C. in 1% quinone, but it was attained in less than 5 minutes a t 50" in 2% quinone. Stretch should be applied under any of these combinations of temperature and time to be of most benefit. If the fiber is to be stretched not more than 100~o, however, there is considerable latitude in the time a t which stretch may be applied. The reaction of quinone with casein appears to be irreversible in neutral solutions. Casein fiber hardened with quinone is superior to formaldehyde-hardened fiber with respect to brittleness and resistance to water. Quinone hardening was most effective near the isoelectric point of casein. Although the nature of the reactions is still unknown, quinone has been found to react with proteins and many amino compounds ( I , 2); most of these reactions proceed readily in aqueous solution a t room temperature. It has been found (4, 6) that deaminized collagen (hide powder) fixes about 60% of the amount of quinone fixed by untreated collagen in 24 hours. It is thus probable that the e-anino groups of
Vol. 37, No. 7
lysine are available in proteins for reactions of this type, but that they account for only part of the reaction. The modification of casein by acetylation, deamination, or esterification, as well ss the addition of small quantities of quinone or formaldehyde, markedly decreases the ability of cssein to form fibers in the presence of water. ACKNOWLEDGMENT
The authors are greatly indebted to R. Hellbach and N. J. Hipp of this laboratory for designing and constructing the equipment used in this development. Also they wish to record their gratitude to Alice Wolferd, Helen Dearden, and Edith Polis for valuable aid. LITERATURE CITED
(1) Fischer, E., and Schrrtder, H.,Ber., 43,525 (1910). (2) Meunier, L.,and Seyewetz, A., C m p t . rend., 146, 987 (1908). (3) Millar, A.,J. SOC.Chem. I n d . , 18, 16 (1899). (4) Thomas, A. W., and Foster, S. B., J. Am. Chem. Sac., 48, 489
(1926). (5) Thomas, A. W., and Kelly, M. W., IND.ENQ.CHEM.,16, 925
(1924). (6) Todtenhaupt, F.,German Patent 170,051(1904). PBESENTED at a meeting eponaored by the American Society for Teating Materials, Philadelphia Distriot Committee, September, 1943.
Phase Equilibria in Hydrocarbon J
Systems J
VOLUMETRIC BEHAVIOR OF ETHANE-CARBON DIOXIDE SYSTEM
T
HE widespread occurrence of carbon dioxide in natural gas mixtures from petroleum reservoirs makes desirable a more complete knowledge of carbon dioxide-hydrocarbon systems. Data from the published literature are sparse. Sander (9) and Wan and Dodge (11) investigated the solubility of carbon dioxide in benzene. The volumetric behavior of the methanecarbon dioxide system was recently studied ( 6 ) . The work reported here represents the second of a proposed series of investigations undertaken by the authors' laboratory for the purpose of establishing the general behavior of carbon dioxide in hydrocarbon systems. Ethane, obtained from the Carbide and Carbon Chemicals Corporation, w m subjected to triple fractionation at atmospheric pressure with a reflux ratio of approximately 50 to 1 in a Pfoot, vacuum-jacketed column packed with glass rings. Initial. and final cuts amounting to 10% of the charge in the kettle were discarded in each fractionation. The overhead was condensed in vacuo at liquid air temperatures with continuous removal of any condensable gases which might have accumulated during the condensation process. The purity of the material so obtained was verified by the constancy of its vapor pressure. AB 80' F. the observed bubble-point and dew-point pressures differed by less than 0.3 pound per square inch. Carbon dioxide was prepared by the thermal decomposition of
reagent-grade sodium bicarbonate. The gas was dried a t atmospheric pressure by passage in succession through a water trap a t 32' F., a tube packed to a depth of 12 inches with calcium chloride, and a similar tube packed with barium perchlorate. The dried gas WM then condensed in vacuo a t liquid air temperatures with continuous evacuation of noncondensable gases. The resulting material had a vapor pressure at 32' F. which differed from that of pure carbon dioxide by less than 0.1 pound per square inch. EQUIPMENT AND PROCEDURE
A detailed descript,ion of the apparatus has been published (8). No changes in the equipment were necessary for the present work. The components of the mixtures were introduced gravimetrically into the volumetric apparatus from small steel sample bombs which could be weighed directly upon an analytical balance. Great care was excrcised in preparing the mixtures. The equilibrium cell and connecting lines to the sample bombs were evacuated to an absolute pressure of 10-4 mm. of mercury before admitting the sample. Residual gas left in the connecting lines was condensed back into the sample bomb by means of liquid air. The change in the weight of the sample bomb was determined upon an analytical balance using the method of tares and
H. H. REAMER, R. H. OLDS, B. H. SAGE, AND W. N. LACEY California Institute of Technology, Pasadena, Calv.
