Synthesis and study of polyferrocenylnitrile

Synthesis of polyferrocenylinitrile

787

condensation the reaction would mainly take place in the para-position, which is more reactive in phenol. The fact that this reaction takes place at a temperature over 250 ° confirms the greater probability mechanism of phenol dehydration. CONCLUSIONS

(1) The possibility of obtaining polyphenylenes from phenols was investigated. (2) The effect of reaction conditions on the yield and solubility of the polymers was studied. (3) Polymers of low molecular weight were obtained which have a narrow signal in the electron spin resonance spectrum. The number of uncoupled electrons is 101°-1019 per g. (4) The structure of the polymers was studied. The benzene rings are probably linked in the ortho-position.

Translated by E. SEM~E REFERENCES

1. G. GOLDFINGER, J. Polymer Sci. 4: 93, 1949 2. G. A. EDWARDS and G. GOLDFINGER, J. Polymer Sci. 16: 589, 1955 3. J. BARCEL and R. REN]~, Compt. rend. 17: 1801, 1961

SYNTHESIS A N D STUDY OF POLYFERROCENYLNITRILE* T. P. VISHNYAKOVA,

I. A. GOLUBEVA

and YA. M. PAUSHKIR

~

I. M. Gubkin Institute of Petrochemical and Gas Industry, Moscow

(Received 1 July 1964) POLYMERS with a system of conjugated bonds have recently attracted increasing attention. These polymers have interesting electrophysical properties and in many cases are semiconductors. As is well known, the conductivity of polymers increases on incorporating nitrogen atoms into the conjugation chain, whose electrons take part in the combined system of n-electrons of conjugated double bonds. The ability of ferrocene to sustain a temperature of up to 400 ° makes it possible to obtain heat-resistant polymers from its various derivatives. Investigation showed that some ferrocene-containing polymers have unusual magnetic properties [1-3]. In the light of the above, it was of interest to synthesize a ferrocene-containing polynitrile not described in the literature, and investigate some of its properties. * Vysokomol. Soyed. 7: No. 4, 713-716, 1965.

788

T. P. VISHNYAKOVAet al.

Very few ferrocene-base nitrogen-containing polymers are known, They comprise polyamides obtained by inter-phase polycondensation of 1,1'-ferrocenedicarboxylic acid dichloran_hydride and certain diamines [4], polyazines obtained from 1,1'-diacetylferrocene with hydrazine [5] and polyazophenyleneferrocenes obtained by the reaction of 4,4'-diphenylbisdiazonium and 4,4'-diphenylenebisdiazonium-3,3'-dicarboxylic acid with ferrocene [6]. This paper is devoted to the synthesis of polyferrocenylnitrile and the investigation of its properties. Polyferrocenylnitrile was synthesized by polycondensation of carbamyl ferrocene in the presence of zinc chloride and phosphoric anhydride as catalysts. Investigations carried out by various authors [7, 8] showed t h a t the chemical equilibirum during macromolecular synthesis is displaced by the ordering of monomer molecules in complexes with salts of coordination unsaturated metals (ZnC12, AlOla, TiCI4, etc.) Thus, intensive polymerization of the C - N bond could be achieved with a great number of nitriles to form polymers with conjugated bond systems. During polycondensation of earbamylferrocene (I) in the presence of ZnCl 2 in the first stage of the reaction, ferroeenylnitrile (II) is formed, followed by complex-formation and ordering of molecules and as a result of subsequent polymerization of the C - ~ bond, polyferrocenylnitrile (III) is formed.

_/

CONHI

< > n

Y

Fo

A

<_> (I)

m ZnCls

-.H,O

/

C =N

< > •n

t Fo

V f

m ZnCl~

Fo

I

A

< > (II)

I

_

(III)

n

The effect of reaction temperature o n polyferrocenylnitrile yield was studied for 5 hours reaction time and a monomer : zinc chloride molar ratio of 1 : 1. I t can be seen from tabulated data t h a t the yield of insoluble polyferrocenylnitrile increases with rise of temperature and is 67-7~ at 170 ° and the yield of soluble polyferrocenylnitrile decreases. To elucidate the effect of reaction time on polyferrocenylnitrile yield, the reaction time was varied from 1.5 to 5 hours at a constant reaction temperature of 140 ° and a m o n o m e r : z i n c chloride molar ratio of 1 : 1. The polyferroeenylnitrile yield increases with increased reaction time. On changing the monomer : catalyst molar ratio from 1 : 1 to 1 : 0.2 at constant temperature (140 °) and reaction time (3 and 5 hours), a m a x i m u m polyferrocenylnitrile yield (60.4Yo) was obtained with a m o n o m e r : c a t a l y s t molar ratio of 1 : 1 (see Table). Investigation of polycondensation of earbamylferro-

789

Synthesis of polyferrocenylinitrile E F F E C T OF R E A C T I O N C O N D I T I O N S OF P O L Y F E R R O C E N Y L N I T R I L E Y I E L D

Reaction conditions catalyst ZnC1 Same ,7 ,7

,7

P=O5 Same

temperature, °C

Time, hours

170 140 100 80 140 140 140 140 140 140 140 140 140

I Polymer yield, °/o of theoretical Molar ratio of ~Soluble in monomer : cata-I dimethyl Insoluble lyst i formamide

5 5 5 5 3 1.5 3 3 5 5 0.25 0.25 0.25

1:1 1:1 1:1 1:1 l: 1 1:1 1 : 0.36 1:0.2 1:0.2 1 : 0-36 1:2 1: 1 1 : 0.2

14'4 19"5 36"2 23"7 22'3 30"4 9"0 11"0 48"6

67'7 46"0 26"5 6"3 30-0 27 "4

27 "9 14'5 13"2

total 67"7 60'4 46"0 42"5 53'7 49"7 30"4 9'0 11"0 48"6 27"9 14"5 13"2

cene in t h e presence of p h o s p h o r i c a n h y d r i d e a t 140 ° a n d different m o n o m e r : c a t a l y s t ratios (from 1 : 2 to 1 : 0.5) showed t h a t t h e m a x i m u m p o l y f e r r o e e n y l nitrile yield (27.9 ~ ) is o b t a i n e d w i t h a m o n o m e r : c a t a l y s t r a t i o of 1 : 2. T h e p r o d u c t s of p o l y c o n d e n s a t i o n are p o w d e r s r a n g i h g f r o m b l a c k to light b r o w n in colour, a c c o r d i n g to r e a c t i o n conditions, a n d p a r t i a l l y soluble in dimethylformamide. N o n e of t h e insoluble p o l y c o n d e n s a t i o n p r o d u c t s m e l t below 500 °, t h e soluble p r o d u c t s d e c o m p o s e in t h e r a n g e of 420 to 500 ° a n d h a v e a m o l e c u l a r w e i g h t of ~ 1200. I R a b s o r p t i o n s p e c t r a of t h e polyferrocenylnitrile o b t a i n e d (Fig. 1) include a n a b s o r p t i o n b a n d of 820 c m -1 characteristic of ferrocene, a n d a b s o r p t i o n m a x i m a a t 1000 a n d 1100 c m -1, characteristic of free c y c l o p e n t a d i e n y l rings of ferrocene. C o n s e q u e n t l y o n l y one c y c l o p e n t a d i e n y l ring t a k e s p a r t in p o l y m e r

~80

T

I

I

L

L

I

800 1000 1200 1400 1600 1800 2000v,en'/-~ FIG. 1. I R Spectra

of

polyferrocenylnitrile.

790

T.P. VISHNYAKOVAet al.

formation. The broad intensive band in the 1600-1650 cm -1 region corresponds to absorption by the --C=1~-- conjugated bond system. According to elementary analysis and I R spectroscopy data, the polymer unit has the following structure --C=N--

I

< ) i I

Fc

/\

<__> CnHgFeN.

Found, ~ : C 63.56; 1-1 4.41; N 6.89. Calculated, Yo: C 62.60; H 4.27; N 6.63.

In polymers obtained a t 170 ° and higher temperature a somewhat increased carbon content and reduced iron content is observed, which m a y be the consequence of exchange reaction between zinc and iron of forrocene and consequent partial breakdown of the ferrocene structure. The polyferrocenylnitrile obtained gives a signal in the electron spin resonance spectrum corresponding to a number of electrons with uncoupled spins of 10is per g. The dependence of electrical conductivity on temperature (Fig. 2) was investigated. The measurements were conducted in a vacuum of 10 -4 mm and

ln(~,lO19 ~.%~/_ E=0.480eV X'i ~X

/~×

E=O724eV"\

×~x~× ~.E=O.362eV x,~ ×

x'%x

E=O.2ITeV ~,~,, x"x-

2 i

1.5

1

I

I

i

2"0

i

I

i

I

L

2.5

i

i

i

1/'T,10 s

I

i

i

3"0

FIG. 2. Dependence of electrical conductivity (~) of polyferrocenylnitrile on temperature: /--relation of ~=a' (T) at I x 10-4 mm after conditioning the specimen at up to 50°; 2--relation of ~=~' (T) at 1 x 10-~ mm after conditioning the specimen five times at up to 50,-300, 300, 300 and 300°C.

Synthesis of polyfcrrocenylinitrile

791

over the t e m p e r a t u r e range of 20-300 ° . T o eliminate f r o m the surface a n d f r o m t h e specimen v o l u m e t h e substances w h i c h are c o m p a r a t i v e l y easily desorbed (gases, air, steam, etc.) t h e pellets, prior t o each m e a s u r e m e n t , were k e p t a t 1 × 10 -a m m a n d 50 ° for 3 hours. The c o n d u c t i v i t y of polyferrocenylnitrile a t 50 ° is 2.2 × 10 -1°. EXPERIMENTAL

Carbamylferrocene was obtained from ferroeene and carbamylchloride in the presence of aluminium chloride as catalyst [9]. The carbamylchloride required for this synthesis was obtained from ammonia and phosgene at 500° [10]. Since carbamyl chloride decomposes on standing to cyanuric acid and hydrogen chloride, it is more convenient to use its stable equimolecular complex with aluminium chloride in the reaction [10, 11]. We synthesized carbamyfferrocene using a complex of carbamyl chloride with aluminium chloride, prepared in dichloroethane solution, unlike the published methods [9] in which earbamyl chloride was used directly. The carbamylferrocene yield in both cases was approximately the same, 70-71%, melting point 168-170 °. According to literature data melting point is 168-171 ° [9]. Found, %: C 57.68; 58.06; H 4.87; 4.97; N 6.17; 6.26 CllHllFeNO. Calculated, %: C 57.7; H 4-62; N 6.13

Polycondensation of carbamylferrocene was effected in the presence of zinc chloride in test-tube type autoclave. Zinc chloride before being introduced into the autoclave, was heated, cooled in a drier to room temperature, crushed to powder and carefully mixed with carbamylferroeene. After the reaction the products of polycondensation were washed with dichloroethane to free them from unreacted carbamylferrocene, then with 10% hydrochloric acid until a negative reaction was obtained for zinc and iron; and with water to give a negative reaction for C1- ions. The washed polymer was dried in vacuum and dissolved in dimethylformamide. After filtration of insoluble polyferrocenylnitrile, the soluble polymer was precipitated from the filtrate with water. Polycondensation of earbamylferroeene in the presence of phosphoric anhydride as catalyst was effected in a flask at a residual pressure of 2 mm. The reaction took place at 140° and was basically complete in 15-20 minutes. The products of polycondensation were treated with dichloroethane to eliminate unreacted earbamylferrocene and washed with hot water until a negative reaction for PO~" ion was obtained. The polymer soluble in dimethylformmnlde was precipitated with water. CONCLUSIONS (1) P o l y f e r r o c e n y l n i t r i l e was synthesized by polycondensation of carbamylferrocene in t h e presence of zinc chloride a n d p h o s p h o r i c a n h y d r i d e as catalysts. (2) The s t r u c t u r e of t h e p o l y m e r o b t a i n e d was confirmed b y e l e m e n t a r y analysis a n d I R spectroscopy. (3) The effect o f t e m p e r a t u r e , reaction t i m e a n d m o l a r ratio of m o n o m e r : c a t a l y s t on polyferrocenylnitrile yield was investigated. (4) The properties of polyferroeenylnitrile were studied. The dependence of electrical c o n d u c t i v i t y on t e m p e r a t u r e was examined.

Tranalated by E. SE~RE REFERENCES 1. A. N. NESMEYANOV, V. V. KORSHAK, V. V. VOYEVODSKII, N. S. KOCHETKOVA, S. L. SOSIN et al., Dokl. Akad. Nauk SSSR 137: 1370, 1961

792

S.D. STAVROVAet al.

2. A. N. NESMEYANOV, A. M. RUBINSHTEIN, G. L. SLONIMSKII, A. A. SLINKIN,

3. 4. 5. 6. 7. 8. 9. 10. 11.

N. S. KOCHETKOVA and R. B. MATERIKOVA, Dokl. Akad. Nauk SSSR 188: 125, 1961 A. A. DULOV, A. A. SLINKIN and A. M. RUBINSHTEIN, Vysokomol. soyed. 5: 1441, 1963 F. W. KNOBLOCH and W. H. RAUSHER, J. Polymer Sci. 54: 651, 1961 Yu. V. KORSHAK, Dissertatsiya, 1964 A. A. BERLIN, B. I. LIOGON'KH and V. P. PARINI, Vysokomol. soyed. 5: 330, 1963 V. A. KARGIN, V. A. KABANOV, V. P. ZUBOV and A. B. ZEZIN, Dokl. Akad. Nauk SSSR 159: 605, 1961 V. A. KABANOV andV. P. ZUBOV, ZhVKhO im, Mendeleyeva 7: 131, 1962 W. F. LITTLE and R. EISENTHAL, J. Amer. Chem. Soc. 82: 1578, 1960 H. HOPFF and H. OHLINGER, Angew. Chem. 61: 183, 1949 F. ULLMANN, Encyklop/klie der teehnischen Chemie, 3 Aufl., Bd. 5 Mfinch.--B., S. 70, 1954

EMULSION POLYMERIZATION KINETICS OF METHYL METHACRYLATE IN THE PRESENCE OF ORGANIC ACIDS AND AMINES AND CATION-ACTIVE EMULSIFIER* S. D. STAVROVA, M. F. MARGARITOVA a n d S. S. MEDVEDEV The M. V. Lomonosov Institute of Fine Cher~ical Technology, Moscow

(Received 1 July 1964) W E SHOWED in t h e p r e v i o u s p a p e r [1] t h a t m e t h y l m e t h a c r y l a t e (MMA) polym e r i z a t i o n in emulsions can be i n i t i a t e d b o t h b y t h e benzoic acid ( B A ) - d i m e t h y l aniline (DMA) s y s t e m a n d b y d i m e t h y l a n i l i n e alone. A d e t a i l e d s t u d y is m a d e in this p a p e r of t h e p o l y m e r i z a t i o n of MMA in emulsions stabilized b y c e t y l p y r i d i n e chloride (CPC), p o l y m e r i z a t i o n being init i a t e d b y t h e B A - D M A s y s t e m a n d b y d i m e t h y l a n i l i n e alone. EXPERIMENTAL Purification of initial substances, methods of investigation and determination of polymer molecular weights have been described previously [1]. All experiments were carried out at a monomer : aqueous phase ratio of 1 : 2 (by volume). RESULTS AND DISCUSSION

Polymerization of methyl methalerylate, initiated by dimethylaniline. I n order to elucidate t h e effect o f emulsifier c o n c e n t r a t i o n on t h e r a t e o f p o l y m e r i z a t i o n of MMA, e x p e r i m e n t s were carried o u t w i t h [DMA] ----0.015 mole/100 ml of a q u e o u s * Vysokomol. soyed. 7: No. 4, 717-724, 1965.