SULFONAMIDE PLASTICIZERS AND RESINS HOU ARD S . BERGEN, JK., . ~ V J. D ICE_U_UETHCK-kVEK Iforisanto Chemical Cornpciny. S t . Loris 4 , kfo.
' h e sulfonalnide plasticizer* am1 resit13 are conipaiible with, an$ impart many desirable characteristics, such as gloss, toughness, and adhesion, to a wide lariety of resins, including cellulose nitrate, cellulose acetate, ethjlcellulose. nylon, and zein. Physical tests. including tensile strength, elongation, water permeability, and flexibilit? \+ereconducted on cellulose nitrate and cellulose acetate films a n d sheets plasticized w i t h t h e sulfonamides and ti-ing d i b u t j l phthalate, camphor and diniethll phthalate, and diethyl phthalate a n d triacetin as t h e respectile control plasticizer-. Tests were al-o conducted o n injection-
.
SO;. NHz I
so2 NWR
molded spec iniens. I n < ellulose acetate, ~ulforiarnide plasticiLers impart greater flexibility and lower water permeabilitj t h a n the control plasticizers. The gitlfonaniide resins ?ield films of high tensile strength and eutremel? low water pernieabilit?. In cellulose nitrate t h e sulfonamide- pile filnis of greater tensile strength, elongation, a i d flexibility t h a n t h e control,. The sulfonaniide resins decrease water permeabilit: , increase sollent resistance, and sharpen t h e melting point. Some applic*ations of thebe plasticizers and rebins in t h e paint. \art>ish, and plastics inductrj'are cliscuiced.
of high melting point, whereas ,\--substituted
September 1947
INDUSTRIAL AND ENGINEERING CHEMISTRY
lizing point. A\lkyl substitution on thr aryl group of the sulfonamide causes considerable variation of melting point, and generalities can be d r a w only from whstitut,ed sulfonamides oi the WIIIC aryl group. Iicssins may be formed by c o n d e n ~ i n y the various sulfonamides mitt1 aldehydes suvh ar fornialdehytie, furfuraldehyde! and act~taldrh~-tle. Pulionaniidc resins of a fusible and x ~ l u b l et!-pe result from the condensation ot formaldeti;-dc J v i t h aryl monosulfonamiiit.s, such ah p-t,oluenc' sulfonamidr. I n thi, opinion of various i n v c 4 gatcii,. (6. 13'1 the monoa1,yl hulionariiirle icwiii. iiuiy be considered as -upercooled mt.lt c i i i m i x r i m - of urichanged sulionaniidt~~ and trinici~ir. iiiciIi~-lenc~deriv:itivri: having t t i t ' F~~llon.irig ucture:
TABLEI.
1083
dt~12EOS.l.\IIl)F:PLASTICIZERS A S D I l E d I S d
Trade Sarrie
Compound .Y-Ethyl p-toluene suliuii:irr.ide ,Y-Ethyl 0- d: p-toluene sulfon-
Santirizer 3 Santicizer Santicizer Santicizer Santicizer Santicizer
Meltiiig P;int,
Colur a n d Forin
c:
( ryatallizariuii Pnin-.
- c.
IVliite solid
8
14
!I
1O.j
139 128 127
.-anticizer 130 aniide SIised .V-isopropyl benzene sulfonaniide &- S-iai>propyl toluene sulfonaniide Condeiisatioii products of aryl sulfonaniides a n d foriiialdehyde A sulfonaniide alkyd reziii
137 3-2
C o l o r l e ~ sliauid Colurless liquid
-- :{I1
Colorless, brittle resin Colorless, brittle resin Cdurless, viscous resin
,,
1lie wlfonaniide resins and phbticixt'rb are i~~iiilxitil)lr~ \\.it11 ; I I I I ~ impart many desirable characteristics, such as gloss, ioughric's.. arid adhesion, to a wide variety of resins [Table 111). 111t hir : ~ l t i subsequent tables the abbreviations X/C, C/.\c, C :in11I.: '(: represent cellulose nitrate, cellulose rieetat i cel l u l o v ;ic.c,t;tt ( butyrate, and ethylcellulose, respectively. Thcje compatibilities were determint:d by casting the tihi Ero11i solution, drying, and storing for one w e k at 95% rcltltivt, 1111n i d i t y . The masiniuni compatibility is dependent upon I I ~ : ~ I I Y variable.= such as t h e percentagc nitration, acc,tyltttioIi, etc., of the base material as the case niay bc; rhv I tioiis a t t h e time of casting (temperature, relrtive humidity) artti of solvent used. Therefon), Table 111 should s e r w only it, :i gtineral indication or' the, rclati'i'e compatibilities. Compatibilities above 100 PHR ] p a r t s per hundrctl parts wsin) ~ e r t not , tried; lion-ever. it is known that in soveral caws the plnstic.izcirs are compatil)le to 300 PIIP,. .Ilthough thi, liinirs of compatibility are not shown llcre, it, is h o l m that thc' wlfonaiiiides are compatible n-ith, arid in some caws actuallj, enTer into, the reaction of various thermosetting plastics such as urea-formaltkhyde, melamine formaldehyde, and phenol-for,maldchyde. Herr they impart an increa3ed f l o ~ vor plasticity, which makes possible laminated punching stock or postforniccl articlw, and decreased molding pressurcs and tcmpcra turt+. Both t h r sulfonaniide resins and plasticizers niay he us1.d to plasticize various polyamides (1, 2, 8, 9, 11). Often additional plasticizers such as the phthalyl glycolates arc addeti t n improvr j,
%r(l rmd infucibli. I t h > foilon. t i i r wnric.ri.~ationof iornialdeliydr with tli- and trijulfnnnniides or anilirie Hulfonamide (sulfanilamide) ( I ? J , In thc, latti,r cnse the relative positions of the amine groups arc important in producing a n infusible resin. For example, aniline o-sulfonaniitlr x i t h formaldehyde yields a fusible resin (initial softening point 100-118" C. and final softening point 1051.57 ' C.), I t iq h c l i e ~ e dt h a t steric hindrance inhibits the primary wartion of the amide with The aldehyde or diminishes the polyni(hiizatior1 capacily of the primary condensation product. On the other hand, aniline p - or m-sulfonamide condenses n-it11 formaldehyde to form a n infusible resin. Walter ( 1 2 ) views this reaction as proceeding first t o a methylene-methylol compound containing more than one reactionable group a h i c h reacts furthei, to a polydirnensional ring system. Narvel ( 7 ) and co-lTorkers recrntly presented their hypothesis on the mechanism of ureaformaldehyde reactions a h i c h may, to some extent, explain the. mechanism of aryl sulfonamide-formaldehyde condensations. Coriaideration of the pos3ibility of ring formation is essential as the hardening property is connected with t,he formation of a polydimeneional network. I t is believed t h a t the chemical reactions involved are similar to those which occur in the urea-formaldehyde type condensation, since similar variations of acid and alkali catalyst, amount of aldehyde, temperature and time of r+ action m w t hr (.onsidereti in their nianufacturc.
Plasticizer
PROPERTIES
Obviously a great number of compounds and reains are available. Table I lists the more important sulfonamide plasticizers anti resins and a few of their physical properties. The properties are given for the commercially available plasticizers and resina ani1 riot for the pure compound. Other less important sulfonamide derivatives which have been investigated as plasticizers. and some of their properties are listed in Table 11. Theue compounds are readily soluble in alcohols, ketones, esters, and other organic solvents. They are only very slightly soluble in n.at,er, the greatest water solubility being approsimatt,ly 1y0at, 34" C. This solubility generally may be increased in a n alkaline solution. However, ammonia in some cases lowers the solubility. T h e sulfonamides have very l o a acidity, and vary from colorless liquids, which form a glassy solid a t -30" C., to relatively high melting solids and wsinn,
S - M e t h y l benzene sulfonamide S-n-Propyl benzene sulfonamide .\--.illy1 benzene sulfonamide S-sec-Heptyl benzene sulfonamide S , S - D l m e t h y l benzene sulfonamide .Y,S-Diethyl benzene sulfonaniide S , S - D i - n - b i i t y l benzene sulfonamide
crysta:. Comi)atibility. l i z a t i o i .~ F'HR" Point, Cellulose Cellulose C. :irerate nitrate 32 >100 36 >loo >io0 - 25 50 .. 23 50 47 40 ,.
.T-Cyclohexyl benzene sulfonamide 91 S-Cyrloliexyl-3,4-dichlorohenzenesulfun~i1~i~l~ 110 .\---illy1 p-toluene ,sulfonamide 64 S-P-Hydroxyethyl p-toluene sulfonamide - 25 S - n - B u t y l p-toluene sulfonamide - 42 S-Butyl glycollyl p-toluene sulfonamide .. N,T-Di-P-hydroxyethyl p-toluene sulfonamide 99 X,.V-Di-n-butyl p-toluene sulfonamide S-Cyclahexyl p-toluene sulfonamide 86 S - M e t h y l xylene sulfonamide -25 Y-cyclohexyl diphenyl sulfonamide 157 S,.l'-Di-n-butyl phenylene disulfonaniide 06
..
a
Parts per hundred parts of resin
I
>I00 >lo0 30
.io 30 < 50 > 100 80 60 30 0
fio
>IO0 0 60
>lo0
>lo@ >lo0
..
50
> 100 >lo0 75 30 >lo0
>
>ino
..
..
>
7i
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
1084 633
low teriiprrature flexibility. TI!? -\'-ethyl 0- and p-toluene sulfonamidt. and 0- and p-tolutmv sulfoirainidc are compatible to the extent iii' 2n and 50 P H R in .shrllac., the former exerting a greattlr at (' cr~nipatible with the' softening act ion. Thr sulio~ianiitlc~ polyviiiyl i~hloi~itii~ t.c,$iiisarid i ~ o p c ~ l y n i c ~hmvevrr, t~i; they ti(, i i ( ~ 1 impart any ~iutsta~itliiig propc'rtiw. In gciieral. tliv .ulionamitie plasticizers which are liquid> at room tt,nipcraturc arc. iiioi't' c*ornpatibleand exhibit better solvelit action tlinii the solid typi,s. IIowt r, txven at low concentrations thv ~olitlsulfonaniidt+ ai t b effc>c.tivein imparting drsirablc iay be niow \vitkly cxhanciid by the use of ausx c h as ilihutyl phthalate. the phthalyl plyrolates, or tricws;?-l phosphatc~.
PLCS7IC z IQ : i . DlETriYL PhThALATL 2. DIMETnYL FHTHALATL 3 G-YCEPDL TRIACETATE
I
0
Vol. 39, No. 9
1
50
25
'5
103
B CELLULOSE ACETATF FINv
-
\
2-
;$. 31BUTVL ? H T H I \ - A T E
2
1050 1010 565 400 455 306 282 3 9 .i
460
C/dc 8 7 7 5
..
5
425 165 31
27 53
4Oi
11
9
..
810 260
465 195 168
..
425 246 256
480 175 39 3 94 270 46
31 23 59 6 17 36
50
75 25 50 75 25 50 "-
5
95 50 75 y5 30
Figure 3.
Elon $tion,
23 :0 75 25
#
Diethyl phthalate
5 4 10
9
Effect of Plasticizer Concentration on Tensile Strength, Elongation, and Flexibility of Cast Films
.
ACETATEFILM
Tensile Strength, F g / / s q . Cni C j n e 600 600
..
--
Diriiethyl ghrhalate
1 8
PLlSTICIZERS O S CaST CELLULOSE NITRATE A S D
..
25 50
Camphor
7
1 . 7 1 2.26 67.5
..
i D
Dibutyl p h t h a l a t e
3 4 5 6
0 17
These dat'a, over the various concentration ranges studied, indicate that the sulfonamide plasticizers and resins are compatible to a high degree with cellulose nitrate, cellulose acetate, cellulose acetat>e butyrate, ethylccllulose, and
S une Santolite M H P
E
i
4 (I
Flow after 2 min. a t 2 7 5 O F . a n d 1500 l b . / i q . in. (.4.S.T~11. D5694 4 T ) . inch 0 58 \Yarer absorption in 24 h r . b y &':inrh-thirk disk (.I.S.T.Al. D5,O2.24 42), B Heat distort6on temp. (.1.S.T.h1. 64 648-45T), Plasticicer lossCiP h r . at 82' C., 1 sinch-thick disk, ci 0.57
TABLE
1085
INDUSTRIAL AND ENGINEERING CHEMISTRY
September 1947
..
450 280 255
3 80 330 270
.. 500
395
..
-is
4'5 310 295
25 50 75
490 d30 300
..
i
8 15 16 354 185 29 460 3 tiu 328
..
&
.u/c 6 2
.. ..
..
7 11
36 8
6 13 24
"U 24
33 55
4JiC 30 7
C/Ac
N/C
100
100
67 32 22 16
51 .. .. ..
22 16
50 53 48
31 63 96 ii0
.. .. ..
100
..
20
27
..
..
11
72
..
..
67 62
..
70 67
..
24 12
..
..
4
59 70 90
38 13
67 61 55
19 75 159 38 46 66
27 26
.. ..
15 10
26
27 22 14
6 11 5 5 16
.. . s 5
6 4
24
1 0
%
20 6
4
,
14 7
..
5
16
CJ'Ac 30
..
..
Water Permeability,
Schopper Folds
..
..
3
..
..
37 2a 28 15 :3 9
is
70
47
67
..
..
56 98
..
49 57 105 47 68 87
89 84 79
.. ..
..
36 65
99
89 84 96
.. .. 84
77 71 70 a7 77 84
..
.. ..
.. ..
CELLULOSE ACErATE
Figure 2, .i arid H , illustrai ('b thts vffect of increasing plasticizcr roncentrationh on t h r tensile strength of erllulose acetate film. Thts sulfonamide plastickwr.5 are comparable i r i tcansile strength rc,tcantiorl to clirneth,)-l phthalate. and diethyl phthalate a i d superior to triacetin. The sulfonamideh in cellulose acetate apparently have a ccrtairi range of plasticizer corlcentratiou (50-75 P H R ) in Lt-hich thc elongation increases riomially; the tensile stlength is only slightly a f f t w d Figure 2H and 3). Figurc. 3 also illustratrs the, grcsater flexibility (Schoppcr folds) obta.inablrs n-lion cc~llulow acrtate is plastiriztd with sulfonamitlt~plasticizers as c.oriiparcd with dinicthyl I J ~dicit hyl phthalate&. Figure 4 indicate? percentage water permeability (vontrol taken as 100%) of ccllulose acetate film. modified n-ith variou? plasticizers. Tht. auli'oiiamides sho\v l o \ v t ~ warvr permeahility tiinir t h v wfi:rcric I)lmt ic,izcSw, tlimethyl and diethyl phtlialateq. Thr sulforianiitiv rc,sinr arv superior i i i t hvir low water pt~rnit~ahility a n d high t c i d v strcLngth, and the wrenhave a uniqucx p i u p ' r t y of irirrt~a~irig .ric-h a< ti.iphrrly1 phostivit!- of solid plasticin phate. ' In c~c~llulost~ awtat(x . - I I ~ Y . ~ ~ Cthe, Yuli'onaini&>s arc' t w t t c s r . iri nioiiturc, vxpor transfer (Tablis 1-1 than the, pht tuil:it(b>, althilugI1 tho actual nioi,.turt, ~ h w q l l i o l l i- I ~ ~ I I I I ~ J : I I : I ~ I ~ fI ~~ i. i i ~ t l i ( ~ r , ( z
1086
INDUSTRIAL AND ENGINEERING CHEMISTRY CELLULCSE
ACETATE 'ILU
'1'111.
Vol. 39, No. 9 ~suIIiiti:iitiid~~ i t ~ i i i , . :II'I> i i - t z i l ?
September 1947
INDUSTRIAL AND ENGINEERING CHEMISTRY
,Sonit*use has been niatic of the sulfonainide i,vsins in a treatiiig Iluriiin for tcrtile fibers to impi,ove dyping qualitic-, abrasinii. : i i i t l w t e r rcsistancc of thc woven cloth.
(.
_1 .
.ACKSOWLEDG\IEST
l i t ) authors ivish t o cspress their appreciation to the Research Ih*liai'tnicnt,Organic Chrmicals Division, and the Plastics Divi-ion of Ilon.;anto Clicmical Company for fiirnishing rc>r cinta.
LITER-ATURE CITEI)
1087
( ; 3 ) G a i d i i e i , . tl. .\.. Ihlri., 1 . 5 f j 4 , f i M (4) Garduet.. Ti. .\., aiid Iii!,kpatri
Co., I b i d . , 2,187,199 (.Tau. 16. , I:sI;. ( ' H L I I . , 19, !I72 ( 3 ) Gartliier. 11. A , . ani1 Sn-ai,d, G. G , IN?, (19271, (6) AIrlIa*ter. L.,J . A m . Chcni. .Sot., 56,204 ~19.34). 1 , ( 7 ) l l n n - e l . C. S..Elliott, ,J, R..Boettner. F. E., :IIIII ~ ~ u - 1 ~H., Ihid.. 6 8 , 1681 (19461. (Sj Peter-., F.T.(to du Pout C o . ) , U. S. Pat.ent 2.:3:17,h:i-i (1)ec. 2 8 , 1943,. (9) Itichter, I f . J. ( t o du P o n t C o . ) ,I b i d . . 2,342.370 (Fel,. 23, 10448. (10) Schmidt,. .Ilbrecht, Ihid., 758.335 (April 26, 1904). (11) Yaala. G . T. (to du Pont To.), I b i d . , 2,270,487 ( l l n r i t : 1 7 , 1912). ' 1 2 ) Walter. G., Trans. Fnradau Soc.. 32, 400 (193tii. :it
- T L D befure t h e Division of P a i n t , Varnish, a n d P l a h t i c s C lir!lii.rr? the I l O t h \IeP-ing o i t h e AVF;F.IC.AS CHEMICAL F o c , r i . n . Cliii~raeri.Ill
Z-Malic Acid as By-product in Apple Sirup Manufactured by Ion Exchange 33 E. BUCK1 \_UD H. H . VOTTERS? Eacrsterri Keginrirrl K r s e n r c h L a b o r n t o r , . I
.
5'. D r p c i r t m m t oj 4 p r i c i i l t u r r . Philmtlelphicz 18,
*l'lie I-malic acid which i- atl~orbecl o n a n anion exvlianger in the preparation of a I~laiitlapple sirup can be rc('o\ered from the emuelit frorri the sodium carbonate regeneration of the exchanger. Only a slight modification i- tirce-barr in the regular regenerati-e prorrdure to re-
I'IiEI*IOUS paper ( 4 ) described a procedure for the removal of malic acid irom apple juice b>- adsorption on a n anion 1bvclranger used in the manufacture of apple sirup. Deacidift(.;irion results in a lo\ver requirement of lime for thr prwipitation r ! f pcctin than in t h r original sirup proceeq (I?), leaves less calI,iiiiii malate in thc juice, and produces a blander sirup. The 1)rt-cnt paper describes a proccadure n-hereby the malic acid call L , obtaincd :I; a by-product from the deacidification step in the tiiaiiui'acturc of this type of applr sirup. llalic acid can be ti-rci as a food acidulant, and the actire acid might also h a r e .I)rcial application in chemistry, i71iei.e a n optically active comIitiund is desired. It is generally recognized that l-malic acid (levorotatory) is the) I)i,incipalorganic a d in apples, although the presence of citric acid l i x ; Iwen reported (2, 7 , 1 4 ) . T h e absence of other acid simplifies flie procedure, since it, is not necessary to separate acids. S o 6,vicIence of a n acid other than I-malic n-as found in t,he appli, .iuicc used in the experiments reported herein. Charley et al. i . 7 ' prepared malic acid as a by-product in the manufacture of xl)plc treacle. Tlicy iieutralized the excess acidity of the juice \\ i r h calcium carbonate and, on concentrating, obtained a pret4pirate of neutral calcium malate. Juice of high acidity (0.7%) \$:Iused in their 11-ork. T h e present authors m r e unable to tlriplicate their results with juices of a lower acidity (0.4C;) ci~iiinionlg found in America. Active I-malic acid has also t i t v n prepared from maple sugar sand (IS) and mountain ash lwrries (BO). Anion exchangers have been used in the recovery of tartaric acmid from grape wastes ( I O ) . I n the present work the anion cArclinnger is used as a n acid adsorber, inasmuch as the main r)iirpose is the reduction of the acidity of apple juice. Regen1
Present address, Quartermaster Food S Container Institute, Chicago.
111. 2
Present address, H. .J. Heinz Cuiiipniii., Pittshurgil, Ps.
/'(I
co7er what \rould otherMise be waste material. 'Ihe .ic.id is obtained in the regenerant effluent as the solu1)le sodium w l t . precipitated as the nornial calrium salt. and conierted to the free acid b> double decomposition with wlfuric arid.
cratioii is acconiplishrd Kith sodium carbonate solution, ai111 r!le acid is recovered in the regenerant effluent. a s the solublo soiliuin salt and is prccipitatrd from the effluent as the insoluhlf. c:ilt.iuiil salt. Free malic acid is very difficult to crystallize. Tlir >+1)1)1(\ sirup manufacturer would probably prefer i o sell the c:il(,iunl malate to cheinical manufacturers, v h o in turn n-ould p r ~ ~ p : i l ~ c ~ the free acid, either in crystalline form or as a concc,iiri,rttcd solution. It was also thought that the distillery waste from applc bi,rincLy manufacture might be utilized as another source of inalic~acid. IIo\~-cver,analysis has shown that such wastes cont:tin litr I(,, it' any, malic acid. Malic acid is partially or completcly ticat i ~ 1 i y 1 ~ 1 during the fermentation procew, probably being convt>rfi.clI I I lactic acid (8). DETERIIIIYATIOS OF MALIC ACID
Since malic \vas the only acid in thc apple juice u < c d iii I t i t , - ( .studies and since it existed almost entirely in the uiicoiiitjinc~~l condition ( 2 ) , determination of the titratable acidity of applt. juice gave its malic acid content. The juice was titratccl w i t h standard alkali t o a pH value of 8.1 ( 3 ) rather than to a plicnolphthalein end point. T h c lat.ter is difficult to read 11cc:tuse of the color of the juice and because of the apprccia1)le darlxniiig which occurs as the acid is neutralized. The method generally employed for determination of sodium malate in the regenerant effluent is based on the fact that nialic acid JTith a uranyl salt forms a coniplex n i t h greatly incrcastd rotatory power ( 6 , 0 , 2 2 ) . X a n y modifications have twrri described in the literature. The one described here is a siniplifiod A.O..l.C. procedure (I),since no other optical1:j active .;uhstaiic,iare present in appreeiahle quantities. dnal! effluent. thpre is no -ug:ii. i n tlic, i~c~gc~nerant
