chloromethylation.benzene trioxane zncl2 hcl

8/9/2019 Chloromethylation.benzene Trioxane Zncl2 Hcl

1/7

Ind Eng. Chem. hod. Res. Dev. 1982, 21, 87-93 87

Literature CitedAmerlne, M. A.; Ough, C. S. Wine and Must Analysis; Wlley: New York,

A.O.A.C. Official Methods of Analysis, 13th ed.; Assoclatlon of Offlclal

A.P.H.A. Standard Methods for the Examlnatlon of Dairy Products; Marth,

Burgess, K. J.; Kelly, J. Ir. J. Food Sei. T d . 1979, 3 1.Davls, J. C. Chem. Eng. 1972, 7 9 , 114.De Boer, R.; De Wlt, J. N.; Hlddink, J. J. Soc. De@ Technd. 1977, 30 112.Delaney, R. A. M. Fm Food Res. 1972, 3 112.Demott, B. J. Fo o d Ro d . Dev. 1972, 24 86.Douglas, H. C.; Pelroy, 0. Blochem. Blophys. Acfa 1965, 68, 155.Engel, E. R. Brltlsh Patent 669894, 952.

EPA. Analysis of Operations and Maintenance Costs for Munlclpal WasteWater Treatment Systems; US. Environmental Protectlon Agency:Washlngton, D.C., 1978 No. 430/9-77-105, 4.

Forsum, E.; Hambraeus, L. J. ab Sei. 1977, 60, 370.Gaden, E. L., Jr. Chem. Ind 1955, 154.Gawel, J.; Koslkowskl, F. V. J. Fo o d Sc i . 1978, 43 1417.Glllles M. T. Whey Processing and Utl llzatl onfconomic and Technical

Goudabanche. H.; Maubols, J. L.; Van Opstal, C.; Plot, M. Rev. Lek. Fr.

HkMhk, J.; DeBoer, R.; Nooy, P. F. C. Zulvdzichf.1976, 68, 1126.Humphreys, M. Roc. 50th Jubilee Conference, N.Z. SOC. Dalry Scl. and

Koslkowskl, F. V.; Wzorek, W. J. ab Sei. 1077, 60, l9S2.Mahmoud, M. M. Ph.D Thesis, Cormell Universt ly, Ithaca, NY, 1980.MaHette M. F. Methods In Mlcroblology;Nonls, J. R., Ribbons, D. W., Ed.;

1974; p 33.

Analytkal Chemists: Washlngton, D.C., 1980; 15.

E. H., Ed.; 14th ed.; Washlngton, D.C., 1978 p 159.

Aspects; Noyce Data Corpn.: 1974; 42.

1076, M .345 , 521.

Technol., Palmerston North, New Zealand, 1977.

Academic Press: London and New York. 1969 Vol. 1 p 521.

Mann, F. M. Proc. 50th Jubilee Conference, N.Z. SOC. Dairy Scl. Technol..Palmerston North New Zealand, 1977.

Morr, C. V. Food Technd. 1976, 30 18.Moulin,0.; GuHlaume, M.; Galzy, P. Bktech. Bloeng. 1980, 22 1277.Muller, L. L. N.Z. J . Daky Scl. Techno/. 1979, 7 4 121.Peters, M. S.; Tlmmehaus, K. D. Plant Deslgn and Economics for Chemical

Englneers; Mc(3rawSIIII: New York, I968 pp 109, 72.Stanler, R.: Adelberg, E. A.; Ingraham, J. The Microbial World. 4th ed.;

PrentlceHall, Inc.: Englewood Cllffs. N.J., 1976; p 256.Swhenbaum, M. S. Clarkson College of Technology, Potsdam, NY, 1981,

private communication.Vllhndt. F. C.; Dryden, C. E. Chemical Engineering Plant Design; McGraw-

HIII: New York. 1959; p 194-248.Walker, Y. Procsedings,, 18th Internatlonal Dalry Congress, 1970, E, 327.Wlngerd, W. H. J . DakySd. 1971, 52 1234.Wlngerd, W. H.; Saperstein, S.; Lutwak, L. Food Technol. 1972, 24 758.Yang, H. Y.; Bodyfen, F. W.; Berggren, K. E.; Larson. P. K. Proceedings, 6th

Natlonal Symposkrm on Food Process Wastes, US. Environmental Protec-tion Agency: Washlngton, D.C., 1975; p 180.

Yoo, 8. W.; Mattlck, J. F. J. Daky Sei. 1969, 52 900.

Received for review May 22 1981Accepted November 3, 1981

This paper w s presentedat the 181st National Meeting of theAmerican Chemical Society, Atlanta, Ga., April 1981,Divisionof Agricultural andFood Chemistry. This esearch was supportedin part by a grant from Dairy Research Inc., Fbsemont,Ill. 60018.

Kinetic Equation for the Ch lorom ethylation of Benzene with Trioxaneand Hydrog en Chloride Using Zinc Chloride as a Catalyst

L. Gutlirrez Jod ra, A. Rom ero Salvador, and V. Muiioz Andr6s

Dpfo. de Fiilcc-Qdmlca de los PIOcesos Industrkles Facultad de Ciencias Odmic as, UniversMad Complu tense de Madrkj,Madrkl-3 Spain

A reaction mechanism is proposed for t h chloromethyiatkm reaction of benzene with trioxane and hydrogen chlorideusing ZnCi, as a catalyst. The experimental data fit the following kinetic equation based on the proposedmechanism: dCp/dt = kpCc[l - (CA/CW)] , where Cp s the concentration of benzyl chloride at time t , k p sthe specific rate constant for formation of benzyl chloride, Cc is the concentration of catalyst, zinc chloride, CAis the concentration of water, and Cw is the maximum concentration of water permitting the catalytic formatiinof benzyl chloride.

Chlorom ethylation reactions can be carried ou t by useof formaldehyde (formalin) and its polymers (trioxane,paraformaldehyde) or chloromethylated compounds(mono- an d dichloromethyl ethers). In mo st cases, it isassumed that molecules of twoor more carbon atoms sp litto give a fragment containing a single carbon atom whichreacts with the aromatic nucleus, introducing a chloro-methyl group.

Formalin in an acid medium (T epnetsina etal., 1967)an d paraformaldehyde in an aqueous medium (Budniv etal., 1971; Shein e tal., 1967; Farverov, 1968) have been usedwith a proton ated acid as catalyst. In these conditions,th e disappearance of formaldehyde is proportionalto thereagent concentration (Llushim e t at., 1971) and to theproton concentration (Mironov et al., 1970, 1971). Theproposed reaction mechanism(Brown an d Kelson, 1953;Mironov et al., 1966; Ogata a nd Okano, 956) is based onth e attack of the arom atic nucleus by th e hydroxymethylcation. Th e compound formed is the corresponding al-

01964321/82/ 221-0087$01.25/0

cohol, which reacts in hydrochloric acid t o give the chlo-romethyl derivative.

Studies carried out with metal halides as catalysts(Llushim et al., 1970) were based on re sults obtained withprotonating acids. T he hydroxymethyl cationor a pro-tonated chloromethyl alcohol (Olah an d Yu, 1975) havebeen proposed as intermediates.

On the other hand, formaldehyde derivatives may bealso converted into dichloromethyl ethers. Th us, di-chloromethyl ether has been obtained from paraform-aldehyde, trioxane,or formalin using an acidcatalyst Buc,1956, Matejiceek an d Furacka, 1966; Kaska an d Mateji-ceek, 1965; Frantisech etal., 1969; Alvarez an d Rosen,1976), dichloromethoxymethane from formaldehydealsousing an acid catalyst (Hea d, 1963), and a mixture of bo thproducts on treating paraformaldehyde with hydrogenchloride ( Sta pp, 1969, 1970). These reactions have no tbeen studied sufficiently and the intermediate compoundsformed a re unknown.

0 1982 American Chemical Society


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88 Ind. Eng. Chem. Prod. Res. Dev., Vol. 21 , No. 1, 1982

Due to th e lack of d ata on t he transformation of poly-meric compounds of formaldehyde into chloromethylethers and on th e mechanism of the formation of chloro-methyl derivatives, i t was decided th at a stu dy on a re-action system th at produces the chloromethylation wouldbe useful. In th e kinetic study, we used benzene to avoidposition isomers and a trioxan ehydrogen chloride mixturebecause it is soluble in th e medium an d does not give offwater. ZnC12 was chosen as the ca talyst because of itsactivity (Belenskii et al., 1971; Mark ridin et ai., 1970).

Experimental SectionEquipment. The experiments were carried out in a

thermo stated sem icontinuous stirred reaction,20 cm highand 10 cm in diameter. Th e mixture of benzene, trioxane,and ZnC12 was placed in th e reactor an d HC1was contin-uously fed into it. T he HC1 gaswas dried over CaClz andZnC12. A rotameter was used to measure the ra te of flowof HC1 gas.

Procedure. T he reagents, benzene an d trioxane, werecharged to the reactor and HC1was introduced to saturatethem. Th e gaseous feedwas 0.3 molfmin. After a certaintime, the c atalyst was added, the gaseous feed reduced to0.05 mol/min, and th e run initiated.

Th e samples were analyzed in a Perkin-Elm er 7 G.L.

chromatograph equipped with a 15% phenylsiliconeDC550 on Celite545 column. Th e column was maintaineda t 70 C for 8 min and then a t 150 C for the rest, witha nitrogen carrier gas flow ra te of24 cm3/min.Results and Discussion

Th e results obtained in preliminary experiments wereused to establish th e following conditions for the remainingexperiments: reagent volume,500 cm3; stirrer speed,2000rpm; initial trioxane con centration,0.25-1.5 mol/L; cata-lyst concentration, 14-40 g/L; tempe rature, 30-50- C; HC1feed, 0.3 mol/min. Und er these conditions, th e gas supplydid not affect the conversion to benzyl chloride if thereagents were previously satura ted w ith HC1. Th e gasabsorption decreased considerably 6 to 20 min after

starting the experiments and the feed was reducedto 0.05mol/min.Influence of the Catalyst and Trioxane Concen-

tration. Series of experiments were carried out at dif-ferent tem peratures varying the catalyst concentration ineach series or the trioxane concentration. Some of theseruns ar e described in Table I, indicating its experime ntalconditions and results obtained.

These results show th e existence of a n induction periodin which dichloromethyl ether a nd water ar e produced , butnot benzyl chloride. This period increases with decreasingcatalyst concentration and increasing trioxane concentra-tion.

After the induction period t he yield of benzyl chloridedecreases with increasing reagent concentration. On thecontrary, the yield of dichloromethyl ether increases.

The concentrationof dichloromethoxymethane is verylow and constant in each experiment. Neither dipheny l-methane nor bis-chloromethylbenzene were detected insignificant amo unts (10.002 mol/L).

Influence of Water. Since the water form ed dissolvesthe catalyst, experiments have been carried out with theaddition of different quantities of water a t the s tar t todemo nstrate their influence on the process. Th e experi-mental conditions and the results obtained are given inTable 11.

The results obtained show tha t the greater th e quantityof water added, the greater is the decrease in formationrate, the yield of benzyl chloride, and the lengthof theinduction period. In a l l the experiments the concentration

m o o o o m o o o o o m o o o o o m o o o o~ m 0 I n I n ~ m 0 I n 0 m N m 0 m 0 0 ~ m 0 o m

H * N r i r i m h l r i r t w m W h l

w m m N 0 0 0 0 w m w ua m t- t d0 0 0 0 ~ ~ N ~ r i ~ * d d d d

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

m o o o o o o m o o0 I n m 0 m 0 m 0 ~ m 0 m o m

I + * r i * e o r i d

II I1h u cp u

oI1 ro I1

O u co

m o m o o m o m o o o m o m o o o o o o oN m t - 0 m F . l m t - o I n o c u m t - o I n o m o m O

r i d r i d e 4 r t W + r i m


3/7

Ind. Eng. Chem. Prod. Res. Dev., Vol. 21, No. 1, 1982 89

AQUEOUS PHASEORGANIC PHASE

f H 2 - O H? PH

CHz\o/CH' /

CL-CHz -0-CHt-O H

C L-CHz-O-CH,-CL

/ f

Figure 1. Reactions of the chloromethylation process: 3, compound of 3 carbon atom s; 2, compound of 2 carbon atom s; 1, compound of 1carbon atom .

Table 11. Maximum Water C oncen tration PermittingCatalysis of Benzyl Chloride Formation

temp, CCAMP,

g-mol H,O/L

30 243242

40 243240

50 24324 0

0.71.11.550.91.31.81.01 . 71.9

of dichloromethoxymethane is constant and has a prac-tically negligible value.

It may also be observed that in the p resence of a certainwater concentration, benzyl chloride formation is pre-vented and this concentration dependson the catalystconcentration. Th is was confirmed by two experimentalmethods.

(a) Experimen ts were carried o ut over a sufficiently longperiod of time for the benzyl chloride concentration toremain constant. Th e amo unt of water produced in th ereaction was obtained by compa rison of the volume of th eaqueous phase with the volume of catalyst solutions inhydrochloric acid of compositions similar to those in theexperiment.

(b) Repeated experiments were carried out, with theaddition of different volumesof water at th e beginningofthe experiment, until the m easurement of th e aqueousphase obtained in each experiment gave the minimumamount of water (added and produced in th e reaction)preventing t he form ation of benzyl chloride.

Th e results obtained show th e existence of a linear re-lationship between the amount of catalystand he amountof water which inactivates the catalyst,CAMP, he pro-portionality constant being 4.8, 5.0, and 6.7 mol ofH 20 /m ol of ZnC12 a t temp eratures of30, 40, and 50 C,respectively.

Nature of the Intermediate Compaunds in theDifferent Synthesis. In order to ascertain the natureof th e intermediate com pounds in the different syntheses

the reaction of dichloromethoxymethane and dichloro-methyl ethe r in c oncentrated hydrochloric acid with gas-eous hydrogen chloride, in the presenceor absence ofZnC12, was carried out. Dichlorom ethoxymethane an ddichloromethyl ether ar e formed. These products wereextracted with carbon tetrachloride. In the same way,trioxane and formaldehyde react to yield dichlorometh-oxymethane. When th e reaction is prolonged for morethan 20 min, dichloromethyl ether is also formed.

Taking into account the need of water for th e conversionof dichloromethyl ether into benzyl chloride, it seemslogical that it react similarly through the action of thewater an d hydrogen chloride and be transformed into acompound containing a single carbon atom, +CH20H,+CH2C1, and C H 20 are the possible structures.

The most characteristic bands of formaldehydeormethylene chloride do not appear in any spectra of thesamples taken. Chloromethyl cation and chloride ionwould form methylene chloride. Neither com pound wasobtained on treating methylene chloride with a catalystin a benze newa ter medium. Nevertheless, benzyl alcoholreacted with hydrochloric acid at high rates a nd withoutth e need of a catalyst. I t seems probable therefore tha tthe carbon fragment is +CH20H.

This has been confirmed by the addition of sodiumhydroxide to th e products obtained by trea tme nt of thevarious reagent with hydrogen chloride in which para-

formaldehydeis formed. These results couldbe explainedby the following reaction.

n(+CHzOH)+ n(OH-) - n(CH20-) nHzOHypothesis of the Reaction Mechanism

Based upon th e experimental results and t he em piricalkinetic equations found (Jodra et al., 1977, 1978) for th eforma tion of dichlorome thyl ether and benzyl chloride, th emechanistic hypothesis shown in Figure1 is proposed.

Th e trioxaneis dissolved into the aqueous phase, formsa complex with the catalyst, and is converted into di-hydroxymethoxymethane and hydroxymethoxy-chloro-methoxymethane, respectively, by t he actionof the w ater,reaction 2, or of HC1, reaction3, the ratio between themdepending on the concentrationof the catalyst.


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00 Ind. Eng. Chem. Prod. Res. Dev., Vol. 21, No. 1, 1982

t

CT*-9

+ 0,170 0 , 3 3

0 50

T 40-0

cc24 g4

2

D l

I

i.

d,

T 5 0 2 C

cc 24 94

0,33

0 0 50

A 0 66

bA

100 200 3 0 000 ZOO 3 0 0300100

It - o i min

Figure 2. Plots of k C values.

It has been experimentally observed (Jodra e tal., 1978)that the concentration of dichloromethoxymethane re-m a h onstant during each experiment and is always low,increasing when th e catalyst concen tration decreases andthe initial trioxane concentration and th e amou nt of wateradde d increase. Th is is justified by the existenceof aca ta lyd and an uncatalyzed reaction, both in t he aqueousphase, in the reaction scheme.

Th e compound containing three carbon atoms, whichonly differ in their chloride content, m ay react w ith wateror with HC l forming a single carbon and atwo carbon atomfragm ents, whose possible stru ctu re s are given in Figure1. Dichloromethyl eth er is obtained by successive rever-sible changes of th e fragm ents an d passes reversibly intothe benzene phase, and the combination of + CH 20Hwithbenzen e produces benzyl alcohol which reacts imm ediatelywith HC1 to give benzyl chloride.

Th e transformation of +C H2 0H nto benzyl alcohol andinto dichloromethyl ether d epends on the presence of th ecatalyst in these reactions,as a t least the first reaction doesnot take place in its absence. From th e fact that th e finalyield of dich loromethyl ether and benzyl chlorideis greatlymodified by t he catalyst concentration, it may be deducedth at th e effects of th e water in these reactions consists inthe decrease of th e catalyst-substrate complex concen-tration.

The induction period existing in the dichloromethylethe r formation (Jodra e t al., 1978), increases with a nincreasing trioxane co ncentration or with th e amou nt ofwater added a t the beginning of th e experiment an d witha decreasing catalys t concentration. This compoun d isproduced mainly from the +C H2 0Hcation by reactions 8to 11. Dihidroximethyl eth er is produced in th e first ofthese reactions and has remained undetected in all theexperiments described. It could evolve according to re-actions 8 and 9, as well as according the reversible reactionscorresponding to th e formation of the three carbon atomcompound. If reaction 8 proceeds more quickly than re-

i t io imin it - min

action 9, the (ZnCl2-HOC H2-0-CH2O H) omplex will notbe formed un til an equilibrium (8) is reached, and t hu sdichloromethyl ether will not be formed.

As the final yield of dichloromethyl e ther dep ends onthe quan tity of added or formed water and on the catalystconcentration, it may be deduced th at bo th substancesmodify the equilibrium . Th ese results may be explainedby consideration of the fact th at reaction8 is practically

irreversible once the h ydroxymethyl cation is stabilizedwith water. As the catalyst is water soluble, the +C H2 0Hand th e catalyst compete for it; thus, the higher the cat-alyst concentration, the lower the + CH 20 H oncentration,the greater the yield of dichloromethyl ether and theshorter the induction period.

Once the maximum + CH 20H oncentration is reached,in absence of th e catalyst, trioxane continuesto disappear,the cation is converted into dichloromethyl ether by re-action 13, and into dichloromethoxymethane by th e re-actions shown in Figure1, provided there is an excessofhydrog en chloride. If there is a deficit of hydrogen chlo-ride, paraformaldehyde separates out,as t has been con-firmed experim entally. T he slow dissolution of dichloro-methyl ether and dichloromethoxymethane in an acidmedium without ZnC12 may be explained similarly.

For the above-mentioned reasons, the induction periodof benzyl chloride should a t least be the sam eas ha t ofdichloromethyl ether. From th e point at which th e hy-droxymethyl cation equilibrium concentrations arereached, the 1 and 2 carbon atom fragments formed fromtrioxane compete for the catalyst. It has been experi-mentally confirmed t ha t the ra te of benzyl chloride for-mation is lower tha n t ha t of dichloromethyl ether, whichindicates that reaction 9 is faster than reaction 12.

As dichloromethyl ether is formed from dihydroxy-methyl ethe r, the water produced will retain th e hydrox-ymethyl cation or the catalyst. Thus, when the cata-1yst:water ratio is large enough for th e catalystto acceptpart of the water formed, the difference between th e in-


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Ind. Eng. Chem. Prod. Res. Dev., Vol. 21, No. 1, 1982 91

3

mol

I -CAMP

3

t-:Jmm


duction periodsw i l lbe small. On the contrary,if the ratiois low, the amou nt of +C H2 0H which can form the(ZnC12C1- +C H 20 H ) complex will be very low a nd th ebenzyl chloride induction period m ay be much longer thanthat of dichloromethyl ether.

When formalin is used without a catalyst, dichloro-methox ymethan e is first extracted w ith CC14 an d if th ereaction is prolonged, dichloromethyl ether is obtained.For tha t the formaldehyde must probablybe transformedaccording to th e reactions 16 and7 to give the hydroxy-methyl cation which then gives dihydroxymethyl ether,which then reacts to give dichloromethoxymethane. Ifhydrogen chloridehas been bubbled through long enough,the equilibria are shifted toward the formation of di-chloromethyl ether and this compound is extracted.

Benzyl Chloride Formation According to t he pro-posed scheme, th e ra te of benzyl chloride form ation willbe proportional t o the ra te of formation of the complex,i.e., t o the +C H 20 H oncentration not stabilized by water.

Th e hydroxymethyl cation is stabilized in water, formsa complex with the catalyst,or proceeds to form one of th ereaction compounds,as paraformaldehyde was not formedin any of the experim ents.Thus, nce the induction period

has elapsed, an d if th e Cc/CTo ratio is no t too high, theconcentration of hydroxym ethyl cation not stabilized bywater will be equal to the concentration of free activecentres. Thus

- -2 klCICc

100 200 300

C1 = no. of free active centers/g of catalyst

Co = g of catalyst/V

(2)

3)

T he conc entration of free active centers will be equalto th e tota l number of active centers less th e numbe r ofoccupied active centers.

(4)1 = CL - c o

CT0

0,33

0 0 50

+ 1,oo

i 00 200 300and the concentration of occupied centers will be pro-portional to the concentration of water not retained by t hehydroxymethyl cation.

( 5 )

CH = k4CA (6)

CO = kf,CA 7)

(8)When th e rate of formation of benzyl chloride is zero

C ~ / k 5 C A M P (9)

CO = kz(CA kBCH)

substitutingdCp/dt = klCc (CL- k5cA)

Then

and therefore

to s the induction tim e for benzyl chloride.Th e first part of the integral in eq13 was repeatedly

calculated using da ta which correspondedto experimentscarried out a t the same tem perature and catalyst concen-tration, with the initial trioxane concentration an d thequan tity of ad ded water as variables. the values of theintegral and the reduced time s correspondingto irst-order


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92 Ind. Eng. Chem. Prod. Res. Dev., Vol. 21, No. 1, 1982

mol/

I

o i 3

/ T 30-0C

0

Q , /

I/+

i

/ mz

0 8

14

I +I

100 200 300

t - f o ) m i n

IiI O

6I

40I

+ A

4,

d

/ +A

iiOl +

I/+4

/ Cao cm?,

0 10

t 14A 20

100 200 300

i f , min

0

/ o

t

0

1

0

I t

2

k,c, 10;

1

100 P o 0 300

i f f . min

A

c 'A

b1 T 5 0 P C


Table 111. Specific Rate Constants

I50c c g l

Figure5. Plots

ofk

values.equation s passing thr ough the origin of th e coordinateswere adjusted (Figures2, 3, and 4). Th e values of th especific rate constantat 30,40, nd 50 C, hown in Table111, were obtained by adjustingthe values of the slopes andthe corresponding catalyst concentration to first-orderequations (Figure5).

B y applying the Arrhenius equation, th e specific rateconstants permit th e calculation ofthe apparent activationenergy and the preexponential factor: E = 6.6 kcal/moland k = 16 mol/g of cat. min. Th us, the equation for therate of form ation of benzyl chloride is

CAMP C A16Cc exp(-6.6/RT)

CPdt CAMP

304050

0.280.430 . 5 5

NomenclatureCi = concentration of compoundi mol of reagent/LC, = concentration of compound i at zero time, mol of

reagent/ LC w maximum concentration of w ater permitting catalyst

action for benzyl chloride formation, cm3/L= time, min

to = induction time for benzyl chloride formation, minV = total reagent volume

SubscriptsA = waterB = benzeneC = catalystDOH = dihydroximethyl etherD = dichloromethyl etherH = hydroxymethyl cationL = total number of active centers of catalyst1 = free active centers of ca talyst0 = occupied active centersof catalystP = benzyl chlorideR = dichloromethoxy methaneT = trioxaneLiterature CitedAhrarez, M.; Rosen, R. T. Int. J. Envkon. Anal. Chem. 1976, 4 , 241-5.Belenskll, L. I . ; Kannanova, I . B.; Kenshtein, Y. B. In kad. M u k . S.S.

S . R . Ser. Khlm. 1971. 5 , 956-63.Brown, H. C.; Kelson, J. W. J. Am. Chem. SOC. 1953, 75, 6292-99.BUC, S. R. Organic Synthesis ; Voi. 36, Leonard, N. J., Ed.; Wlley: New

York. 1956; p 1.Budnlv, I. V.; Mlronov, 0 . S.; Farverov, N. I.; Zhukova. A. I. Uch. Zap.

Yarosl. Tekhnd. Inst. 1971. 27. 70-7.Farverov, M. I. URRS Patent 216693, 1968.Frantlseck, J.; Metejiceek, A.; Kaska, J. Czech Patent 133 269, 1969.


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Ind Eng. Chem. Rod. Res. Dev. 1982, 21, 93-96 93

Heed, F. M. J . chem oc . 1963, 2972-76.Jo ba, L . G.; Romero, A,; Mufioz, V. An . R . Soc. sp. Fis. Quln. 1977, 73

Joba, L. G.; Romero, A.; M u k z , V. A n . R . Soc. Esp. Fis. a m . 1978, 74

Kask a, J.; Matejlceek A. Czech Patent 114453, 1965.Liushim, M. M.: Mekhtlev,S. D.; Guseinlva, S. M. Zh. Org. Khlm. 1970, 6 ,

Liushim, M. M.; Makhtiev, S. D.; Guseinova, S. A. Nefte h/m/ya 1971, 11 ,

Markridin,V. P.; Esipov, G. 2 . ; Fllipov, N. D.; Landoya, V. V. Sb . M u c h Tr.

Matejiceek A.; Fwa ck a, F. Czech Patent 117 267, 1966.Mkonov, G. S.; Farverov, M. I . ; Stein, S. D.; Bespabva, I . Zh . Org. Khhn.

Mironov, G. S.; Budnil, I. V.; Farverov, M. I. ; Stein, V. D. Zh . Org. Khlm.

1485-92.

121.

1432-34.

92-94.

Zuzbas . P o i l i d . n s t . 1970, 26, 206-7.

1966, 2, 1639-44.

1970, 6 , 1224-26.

Mironov, 0 S.; Farverov, M. I . ; Budnil, I. V. Stein, V. D. Uch. Z ap . Yarosl.

Mironov, G. S.; Stein, V. D.; Farverov, M. Y. Uch. Zap. Yarosl. Technd.Tecknd. Inst . 1971, 26, 21-7.

Inst . 1971, 22, 115.@lata, 0 . ; Okano, M. J . Am. Ch em. Soc. 1956, 78 5423-25.Olah, 0. A.; Yu, S. M. J . A m . Chem. Soc. 975, 9 7 , 2293-95.Shein, D. V.; Mironov, 0 S.; Farverov, M. I Z h . Prikl. Khlm. 1967. 4 0 ,

Stapp, R. P. J . Org. Chem. 1969, 3 4 , 1143-43.Stapp. R. P. U.S. Patent 3488393, 1970.Tepnetsina, F. P.; Farverov, M. 1.: Ivanovskii,A. P. Zh . Prlkl. Khlm. 1967,

2006- 14.

40. 2540-6.

Received for reviewSeptember 29, 1980Accepted June 22,1981

Organic Fillers by Anionic Dispersion Polym erization

James 0. Murray and Frederlck C. Schwab

hfobil Chemical Company, Research d Development lfibwatmy, Edlson, New Jersey 08817

Styrene-divinylbenzenemixtureswere anionically polymerizedin the presence of block polymeric dlspersing agentsin aliphatic hydrocarbons. Cross-linkedfine particles with sizes a s small a s severalhundred angstroms couldbereadily prepared by this technique. By suitable control of reaction variables, either isolatedparticles or structuredagglomerates wereformed. The latter agglomerates wereefficient thickeners for hydrocarbon liquids and appearedto maintain their integrityeven under hlgh shearcondi ons. The lMng nature of the anionic polymerization permittedthe introduction of various functional groups onthe polymer chain ends in the particle. This functionality w as usefulin modifyingthe properties of theparticles. For example, colored pigments, water dispersible materials, andhighlyreinforcing flliers for SBR rubber were producedby the appropriate choice of functionality.

IntroductionAnionic dispersion polymerization in hydrocarbons is

a sim ple and versatile procedure ( Bar rett, 1975; Schwab,1973). Th e present studies were stimulated by previouswork in this laboratory in which a thermally and shearstable grease was formed by the anionic polymerizationof sty ren dvi ny lbe nz ene mixtures in motor oil containinga block copolymer dis persa nt (Heilweil and Schwab, 1974).This formation of a thermally and shear stable greasestructure suggested tha t stable agglomerates of very finecross-linked particles were formed in this polym erizationand that by a similar polymerization in low boiling hy-drocarbons, rganic filler materials with unique p ropertiescould be isolated.

In this work itwas found th at under suitable polymer-

ization conditions highly cross-linked (and therefore non-fusing and no nmelting) particles are readily formed usingAB block polymersas dispersants (Figure1 . The reac-tions are simple to carry out (when air and moisture areexcluded), and yields can be m ade q uantitative ; particlesas small as a few hundred angstroms can be prepared.Furtherm ore, the terminal groups in the polymerizationare living polymer anions. Th e reaction products aretherefore ideallysuited to modification of th e chem ical andphysical character of th e particle by a seconda ry reactionat these living polymer sites.It was also observed th at thepolymerization reaction can be controlled to producelargely isolated particles or to produce structured ag-glomera tes of many particles. The se struct ure d agglom-erates maintained th eir integrity under severe conditions

of tempera ture and shear. T he utility of this chem istryin the formation of a variety of types of filler materialshasbeen investigated and its application in a few specificsituations has been studied.Experimental Section. Typical PreparativeExamples

A. Preparation of a High Structure Fine ParticleProduct. In a 3-L flask was placed2 L of hexan e and 6g of M 20 iso pre nea tyrene disper san t of 100OOO molecularweight and the mixture was stirred u ntil dissolved.A smallamount of styrene was added and sec-butyllithiumwasadded dropwise until the orange color of th e styryl anionpersisted. An additional 125.6 mL of styrene and 13 mLof 55 divinylbenzenewas then a dded together with 6 gof 10OOOmol w t polyisopren yllithium dissolved in hexane.

T he reaction was initiated by the a ddition of 6.3 mL of1.2 N sec-butyllithium. Th e mixturewas stirr ed for 2.25h an d the tem pera ture was increased from 32to 54 C withsome warming at th e end of the reaction.

Th e thick reaction mixture was treated by the additionof 0.5 mL of methanol followed by1 mL of acetic acid.Th e product (129g) consisted of structured agglomerateshaving ndividual particles generally less tha n500 A in size.

B. Preparation of a Low Structure Fine ParticleProduct. In a 12-L reaction flask maintained under ananhydrous nitrogen atmosphere was placed8.8 L of hex-ane, 52.8 g of 8020 wt % tert-butylstyrene-styrene dis-persant of 100OOOmolecular w eight and 52.8g of pa ra ff iwax (to aid in redispersion), and th e mixture was stirreduntil dissolved.

0 1982 American Chemical Society

chloromethylation.benzene trioxane zncl2 hcl

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