The effect of plasticization and crystallization of polymers on their electric conductivity, ion mobility and dipole segmental relaxation

THE EFFECT OF PLASTICIZATION AND CRYSTALLIZATION OF pOLYMERS ON THEIR ELECTRIC CONDUCTIVITY, ION MOBILITY AND DIPOLE SEGMENTAL RELAXATION* N. N. MORGV~OV, V. S. SKURIKHINA,V. P. SHUVAYEV and B. I. S A Z ~ ~ Industrial Research Association "Plastpolimer"

(Received 15 August

1971)

TEE plasticization or crystallization of polymers, and also temperature changes, are known to be able to produce considerable changes of the dipole segmental relaxation period ~ [1-3], and of electric conductance 7 [4-6]. Very little is to be found in the literature about the connection between these two processes, with the exception of one communication [7] in which t h e y are reported to run parallel in the case of polyvinylchloride (PVC) as a function of temperature and pressure. There is no information available about the effects of these two factors on ionic mobility ~ determined by an independent method, so that no definite conclusions can be drawn about the mechanism of conductivity in amorphous and crystalline polymers. As plasticization, crystallization or temperature changes can generally produce changes of ionic mobility as well as ion concentration, i.e. 7 (~, X, T)=~qt~(~0, X, T).n~(~, X, T),

(1)

in which q--ionic charge, ~0--plasticizer concentration, X - - % crystallinity, T - - t e m p e r a t u r e , an interpretation of the observed changes of ? must take into account the effects of w and n on the 7This work deals with the study of the mechanisms of the 7, ~ and % changes during the plasticization of amorphous and atactic polystyrene (PS) by slightly polar dioxane and polar acetophenone (A.P), but also with the crystallinity changes in pentaplast (PT), and the composition changes in ethylene-vinyl acetate (CEVA) and ethylene-propylene (CEP) copolymers. EXPERIMENTAL F i l m s a m p l e s of 2 0 - 3 0 0 ~ t h i c k n e s s were p r o d u c e d f r o m 5 - 1 0 % s o l u t i o n s o f P S i n d i o x a n o or A P b y m a i n t a i n i n g t h e m i n a n a t m o s p h e r e of d i o x a n e v a p o u r s . A l l u m i n i u m foil w a s u s e d as a film s u p p o r t a n d also as t h e h i g h - v o l t a g e e l e c t r o d e d u r i n g t h e 7- a n d ~ - d e t e r m i n a t i o n s . T h e m e a s u r e m e n t e l e c t r o d e w a s a 2 m m d i a m e t e r a l u m i n i u m foil m a d e t o a d h e r e t o t h e film w i t h c o n d e n s e r oil. T h e p r e s e n c e of t h e s e electrodes e n s u r e d a c o n s t a n t p l a s t i c i z e r c o n t e n t of t h e P S film e v e n a t e l e v a t e d t e m p e r a t u r e s (80°C); t h i s w a s c h e c k e d * V y s o k o m o l . soyed. A15: No. 6, 1382--1389, 1973, 1552

P l a s t i c i z a t i o n and crystallization of p o l y m e r s

1553

b y weighing t h e sample after each test. A comparison check of the o b t a i n e d y- a n d K-values was m a d e b y t h e i n t r o d u c t i o n into t h e PS films of a c o n s t a n t (0.1 ~ w/w) q u a n t i t y of Cu x "/(NO3)2" 3H~O s i m u l t a n e o u s l y w i t h t h e plasticizer. This ensured a y-increase b y an order of 2-3, as well as of t h e p r i m a r y c o n d u c t a n c e due to t h e ions resulting f r o m t h e dissociation of ~he crystalline }~ydrated copper nitrate. The control tests showed t h a t the i n c o r p o r a t i o n of this salt q u a n t i t y did n o t alter K. P e n t a p l a s t films of 20-120/~ thickness of various crystMlinitics were p r o d u c e d by t h e h e a t t r e a t m e n t of t h e original samples. These were p r o d u c e d b y a 30 rain pressure of 300 k g f / c m z applied at 200°C, followed b y q u e n c h i n g in w a t e r at 4°C. T h e conditions of t h e h e a t t r e a t m e n t s arc listed in Table 1. Value X was v a r i e d f r o m 0.1 to 0-2 d e p e n d i n g on t h e thickness a n d t h e t e m p e r i n g conditions, and was calculated from t h c densities according to formula:

dk(d--d~) X- d(dk--d~)'

(2)

in w h i c h dk = 1-51 and da = 1"386 g / c m 3, i.e. the densities of the c o m p l e t e l y crystalline and a m o r p h o u s p o l y m e r respectively, w h i c h were d e t e r m i n e d at 30°C [8]. The sample densities were d e t e r m i n e d b y the flotation m e t h o d w i t h a ~ : 0 - 1 5 ~ error a n d a 0.95 fiducial limit. TABLE

1. T H E

HEAT

TREATMENT

AND

SOME

OF VARIOUS

OF THE

THICKNESS

PROPERTIES

h

To d e t e r m i n e K

Spec. :No.

S a m p l e 1 at 80 ° S a m p l e 2 at 100 °

PENTAPLAST

FILMS

To d e t e r m i n e ~, 7

Heat treatment <)f samples*

Original t e m pered at 50 °

OF THE

AT 40°C

x

12 26 33 30 35 14 30

1.401 1.400 1.402 1.403 1-404 1"405 1'406i

0.13 0.12 0.141 0.151 0.161 0.17 0.18

7

o

5.0 5-1 5-0 3.2 2-8 1.4 1-1

X

85 108 106 30 110 112 118

1-401 1.401

1.402 1.403 1.404 1.406 1.407

0-13] 0"13 i 0-141 0"151 0'161 0"18 0'19

13 12 -7'5 3"0 2"5 2-0

3'1

2'9 2"8 2"7

5'6 2"8 1'5 l'0

* 24 h r t e m p e r i n g in air. t D e n s i t y a t 30°C.

The X - v a l u e s were also checked b y a n X - r a y m e t h o d . The results o b t a i n e d in two d e t e r m i n a t i o n m e t h o d s are given below: X b y density: 0.12 X by X-ray: 0.18

0.16 0.24

0.19 0.27

T h e r a t e of change of X was the s a m e in b o t h m e t h o d s . The spherulite dimensions were d e t e r m i n e d microscopically on i n s t r u m e n t MBI-6; t h e y were 15-20/~ in all t h e t r e a t m e n t

1554

N.N.

MOlCOUNOV et al.

conditions. The studies on pentaplast were carried out at 40°C when this umtorial was in the higlMy-elastic state (its glass temperature, T , = - - 5 to 10°C) [9, 10]. Ahiminium foil electrodes held on to the sample with condenser oil were used to determine y. The CEVA a n d CEP samples of a variety of compositions were produced in the shape of 20-60/1 thick films b y hot-pressing at 120°C/10 min under 200 kgf/cm ~ pressure, followed b y cooling in streaming water to room temperature. The vinyl acetate (VA) content and t h a t of propylene varied from 1.0 to 18 m o l e ~ ; this resulted in a change of X from 0.18 to 0.02 in the case of CEVA, and from 0.60 to 0.18 in the ease of CEP. The X - r a y method described b y Hcrmans and Weidinger [8-11] was used to determine X with a =l=0.006 absolute accuracy. The VA monomer units were not incorporated in the crystals; their true dipole moment ~* was 1.68 D [12, 13]. The T , of the eopolymers of differing compositions ranged from - - 6 5 to --75°C in the case of CEVA, and was practically constant for CEP (--75°C [14]); it dropped as X became larger. The X-values as a function of copolymer composition are reproduced below: VA, m o l e ~ X Propylene, mole~ X

1.6 0.18

3'5 0.16

5.5 0.14

7.2 0.11

9.7 12 18 0.08 0-05 0.02

1 0.60

2 0.54

3 0.48

5 0.40

7 0.36

8 12 17 0.34 0-29 0"18.

Two aluminium foil electrodes were used to .measure ~,, of which one was pressed on during sample preparation, the other was deposited b y v a c u u m spraying. The electron conductance of the films was measured with the aid of a EK6-7 t y p e electrometer; the relative error was less t h a n -4-20~o. The ionic movement was measured t b y the non-stationary injection flow m e t h o d [15]. The injection electrode was a s a t u r a t e d solution of Cu(NO3)2' 3H~O in dioxane, or in a dioxane-octanol mixture; the salt dissociated into the [CuNOa" 3H20] + cation a n d [NOn]- anion [16]. The injection electrode was represented b y an about 2 m m diameter electrolyte droplet. The dielectric loss t a n 5 a n d the dielectric constant ~' was measured at 57 to 10 e Hz frequency in the temperature range 20-800C on instruments of t y p e UME-10A, P570, E9-4 a n d TRS-10C. The determination errors for these two measurements were with 4-109/o a n d 4- 39/0 respectively at 0.75 fiducial limits, while t h e y were =]=20, 4-25 and 4-5 for pentaplast, CEVA and CEP respectively at 0'95 fiducial limit. RESULTS T h e e l e c t r i c c o n d u c t a n c e ( c u r v e 1) a n d t h e N O T i o n m o v e m e n t ( c u r v e 2) is s h o w n a s a f u n c t i o n o f t h e l o w - p o l a r i t y d i o x a n e c o n c e n t r a t i o n i n P S (e0=2"20, /2*----0.4 D [17, 18]) a t r o o m t e m p e r a t u r e i n F i g . 1. T h e c o m p a r i s o n o f ~ a n d as a function of ~ makes it clear that these values increase by a power of about 3 and parallel when the dioxane content changes in the studied range (from 0 t o 300/o w / w ) . T h e y - i n c r e a s e o f P S d u r i n g i t s p l a s t i c i z a t i o n w i t h a l o w - p o l a r i t y p l a s t i c i z e r is t h u s a l m o s t u n i l a t e r a l l y a f u n c t i o n o f K. T h e ~- a n d z - v a l u e s a s f u n c t i o n s o f ~a c a n b e d e s c r i b e d b y t h e e q u a t i o n

(~)

~ (~),

(0)

~ (0)

----exp ( g l ~ ) ,

(3)

' i n w h i c h ?(0) a n d w(0) a r e e q u i v a l e n t t o ~ = 0 , w h i l e K l - - d i m e n s i o n l e s s c o n s t a n t e q u a l l i n g 2 2 - t - 2 w h e r e t h e p l a s t i c i z e r c o n c e n t r a t i o n is e x p r e s s e d i n w e i g h t f r a c -

Plasticization and crystallization of polymers

1555

tions. The addition of the polar A P to PS (e0= 183,/~*=2.96 D [17, 18]) produced a non-linear log 7-~ function, which differs from the response with dioxane; Value 7 increased more rapidly t h a n w (Fig. lb). )"or example, for ~=20~/o, the value of 7(~)/7(0) was a b o u t 104, while K(~)/K(0) was less t h a n 102. The behaviour of the K--~ is described b y eqn. (3) for k l = 2 0 : E 2 .

b .

,

~

1

L -/2L

-1810

~.,-13

h_,

h

!

l

I

20

l _

I

/cO,~, w~ %

O

1o

20, o, wt. %

FI(~'. 1. The effects of: a--dioxane, b--AP concentrations on: 1 - - t h e y-value of plasticized PS films containing 0-1°'~, w / w Cu(NO3)2-3H20, 2--on the ~ of (NO3)- at 20°C, 3, 4--the K and T~ at 80°C. As the same t y p e of ion is being used to determine 7 a n d K, tile large difference in the t y p e of the 7-q and K-q functions is evidence, according to eqn. (1), of a substantial concentration increase of the charge carriers in 1)S in the presence of a polar plasticizer. W h e n this increase n is due to changes of co, one can write according to the t h e o r y [19] for ~, that: - - - ~ - - - = A exp -K_ +~'+

,

(4)

2 a K T " ~o

in which a - - d i s t a n c e between the anion a n d cation in the ionic pair. The resulting ¢0 are shown in Table 2 for system !)S-AP together with the 7- a n d K-values, which enable us to check the validity of eqn. (4). One can see from Fig. 2 t h a t the log 7/(K_-FK+)(,lependence on l/s0 (curve 1) for the system P S - A P is linear, and t h a t eqn. (4) is therefore a qualitative description of this function. Param e t e r a calculated from the slope of this response line was found to equal 7 A which agrees with the literature d a t a [19-21]. The log 7-X (curve 1) a n d log ~ - X (curve 2) functions for pentaplast are shown in Fig. 3. One can see t h a t the 7- and K- values decrease exponentially when X increases, i.e. t

7 (X) - - - - = e x p (--al" X) 7 (o)

(3a)

(x) =exp (--a2X) , K (0)

(3b)

" ~T. ~T. Mo~Gu~ov et al.

1556

and that ~1=20:J: 3, ~z= 16±2. The similarity of the latter coefficients indicates that the ?-decrease when X increases must be chiefly due to changes of K. The slight changes of y and K during the pentaplast crystallization could be due to sbme change of d (Table 1) or to the non-identity of the ions determining y with NO~, for which the mobility had been measured.

-3"¢

o

-#'2 2

I

-5"0 28

3q

1/2

lO0/~o F:c. 2. The dependence of log y/(~+ + K_) on the inverse e0 for: / - - s y s t e m YS-AP, 2 - - C E V A of various compositions, at 23°C.

:Figure 3b shows that any change of y by two potencies in the measured range will cause hardly any change of K. One can therefor say that K makes only a small contribution to y. The e0 of the copolymer will increase, at the same time, quite 1 7

-

-IZl,8

/

-#'5

,~.

:-5

~

-15"4

-

-

--18

-5"5

@ ~

:

_/5<

@

2

--17

31 0"15

o.2x

10

20 c~molo %

FIO. 3. The effects of X on: 1 - - y , 2--'K, 3--T, in the case of: a - - p e n t a p l a s t at 40°C, b - - o f CEVA composition at 25°0.

substantially on increasing the content of VA groups (Table 2). According to Van Gaut [4] this must result in a considerable change of y owing to an increase of the charge carrier concentration. Accordingly, :Fig. 2 (curve 2) shows t h a t the log 7/(~--t-K+) dependence on l/c0 is linear, and t h a t a = 5 A. Please note that one has to take into consideration the presence of different ions when comparing the y- and ~-values of pentaplast with those of CEVA.

Plasticization and crystallization of polymers

1557

T h e results of t h e y a n d K d e t e r m i n a t i o n s for C E V A of various c o m p o s i t i o n s are g i v e n below: c, mole ~ 7× 10 is, o h m - l . c m -1 K+ "H-h'-

----2

1

2

3

5

7

8

12

17

1.1

--

3-5

--

6-8

--

--

10

× 10 u, cin2/V.sec 0.6

1.2

1"5 1.5

2-0

1.7

3'5

5"0

I n c o n t r a s t w i t h C E V A , t h e s a m e c o m p o s i t i o n r a n g e in CE1~ will p r o d u c e a 7-change b y a p o w e r of 1/10, a n d a p p r o x i m a t e l y t h e s a m e changes of K. Thus, a n increase of t h e p r o p y l e n e c o n t e n t in C E P will cause ~ to change chiefly d u e to c h a n g e s o f K, a n d t h e i r d e p e n d e n c e on c o m p o s i t i o n will be described b y e q u a t i o n s o f t y p e 3a a n d 3b h a v i n g angle coefficients a~-----13, a o = 9 . T A B L E 2. T H E

~o-VALUES AS F ~ J ~ C T I O N S OF P L A S T I C I Z E R CO~NTE1NT (flAP F O R SYSTESI P S - : ~ P , AI~D OF C E V . ~ k C O M P O S I T I O N AT CO:NSTANT TEI~IPERATLTRE

PS-AP (23 °)

CEVA (25 ~)

(flAF~

C~

% w/w

mole %

0 1-5 3 5 6 8

2.4 2.75 3.0 3.2 3.28 3.4

1.7 3-5 5.5 7.2 9.7 12

PS-AP (23 °)

~o

2.48 2.68 2.85 3-02. 3.21

CEVA 25 ¸=)

(flAP~

C/

% w/w

mole%

12 15 18 20 25

3.62 3-7 3'72 3-75 3"78

18

£0

4.0

The comparisons of • with ~. T h e whole collection of our e x p e r i m e n t a l findings a b o u t t h e effects on ion m o v e m e n t s o f plasticizers of v a r y i n g polarities, b u t also o f t h e X o f h o m o - a n d c o p o l y m e r s of v a r y i n g compositions, e n a b l e d us to a s s u m e t h a t t h e shifts o f charge carriers d e p e n d on t h e s e g m e n t a l m o b i l i t y o f t h e m a c r o m o l e c u l e s . T h e d e p e n d e n c e o f t h e m o s t p r o b a b l e s e g m e n t a l dipole r e l a x a t i o n period on v a r i o u s factors, a n d o f t h e ionic m o b i l i t y of all t h e s t u d i e d p o l y m e r s c o n f i r m e d this. T h e results of t h e ~, d e t e r m i n a t i o n s are listed in T a b l e 3. T h e d e p e n d e n c e o f r~ on ~ a n d X can b e w r i t t e n for P S a n d p e n t a p l a s t as

~(0)

3,(0)

:exp

( - - a l , ~)

(5)

= e x p (-}-a2X)

(6)

T h e c o m p a r i s o n o f t h e f o u n d ionic mobilities a n d t h e dipole s e g m e n t a l rel a x a t i o n p e r i o d s s h o w e d t h a t b o t h t h e s e characteristics are s u b j e c t to t h e s a m e q u a l i t a t i v e c h a n g e d u r i n g plasticization as d u r i n g changes o f X of t h e h o m o -

N. N. MOROUNOV eta/.

1558

polymer, or of the copolymer composition. F u r t h e r m o r e , Figs. l a a n d 3 show t h a t w increased in proportion w i t h 1/z~, or remains the same if r~-----const., i.e. x(~, X)" z~ ((p, X ) - const

(7)

This correlation, which is similar to t h e Stokes formula [22] for low molecular weight liquids (x.t/==const where t/--viscosity of medium), is also easily obtained from eqn. (3), (5) a n d (6), i.e.

x)

(0).

(s)

because The comparison of the x- a n d v~-results for a copolymer of constant composition on changing its segmental m o v e m e n t i n t e n s i t y b y heating the sample, for example, is severe enough. T A B L E 3. T H E r~ AS A F U N C T I O N OF D I O X A N E CONTEI~T OF P S , T H E C R Y S T A L L I N I T Y OF P E N T A PLAST, AND T H E C E V A

PS dioxane (80 °) • ~× lOs, @, O/ ,,o

Pentaplast (40°C) X

SOC

10 13 17

20 6"3 1"0

v~× 105, SOC

0'13 0"16 0"17 0"18

1"0 1"8 2"8 5'0

COMPOSITIOl~

CEVA (23°C) c, r~ × 108, mole ~ sac 1.7 3.5 5.5 7.2 9.7 18

/ t

1.82 2.08 2.45

. I

2.63 3.06

CEVA (c=3"5 mole~) T , °C

Ta~ s e c

--25 --19 --12 --3 14 25

1 . 4 × 1 0 -3

1.6 X 10-~ 1.6 × 10 -5 1.6 × 10-6 1-6 X 10 -7 1 . 6 × 10 -8

We d e t e r m i n e d for the above purpose the t e m p e r a t u r e dependence of x± a n d z~ at a fixed c-value. These results (Table 3 a n d 4), obtained in t h e range 14-60°C, show t h a t the t e m p e r a t u r e dependences of ~± a n d z~ are satisfactorily described b y K.( ( 0T ) :)K _+-

exp( \

T--T1]

(9)

(10, in which x+(0) a n d r~(0) correspond with 1/(T--T1)-~0; T l = - - 6 6 ° C , which is the experimentally found t e m p e r a t u r e [23]. We found t h a t the t e m p e r a t u r e coefficients •f a n d a~, were independent of copolymer compositions, i.e. 8 × 10-2°C. The ~± a n d v~ values therefore were subject to the same change with temperature. Valid was in our case the equation K+(T). ~,(T) = const (T), which is identical w i t h eqn. (7).

(11 )

1559

Plasticization and crystallization of polymers

T h e ~T increases in p r o p o r t i o n w i t h t h e V A g r o u p c o n t e n t for t h e n e g a t i v e ion in t h e studied r a n g e of c o p o l y m e r c o m p o s i t i o n s f r o m 3.2 × 10 -~ to 7.7 × 10-2°C. C o n s e q u e n t l y t h e r e is only a q u a l i t a t i v e correlation of t h e a'-- a n d r~-values as a f u n c t i o n of T in this case. So far, it is impossible to c o m e to a n y conclusion for t h e reason of differences b e t w e e n t h e s'+ a n d K- changes as a f a n c t i o n of t e m p e r a t u r e in the ease of C E V A samples. TABLE

4. T H E

K±

VAIAYES FOP. V A R I O U S C O M P O S I T I O N A N D T E M P E R A T U R E S

~-× 10 u, cm2/V.sec 7', °(! ] 12 23 36 42 52 60

4.o 8"3 15"0 21"0 36"0

concentration, mole ~, 7.2 5.~ , 3:5-1 i

4"1 3.7 7'2 6"3 ]2.0 9-0 16.0 12-0 25.0 ! 20-0

3-7 6"0 7"0 10"0 14-0

OF

( : E F A FILMS

a'~ x 10u. em-+/V.scc T, °C 1.7 3-4 5"0 6"0 7"0 8"0

1~ 23 36 42 47 60

4"01 12'0 18"0 26"0 44"0

concentration, lnole ~'o 7:'2! 5 - : 5 - 3 - 5 : 3.0 10"0 16-0 23.0 36.0

1.7-

2"4 I 2.0 1-7 8"2 7'0 i 5"5 13"0 12"0 94 18"0 ; 15"0 15'0 28"0 i 25"0 190

T h e c o m p a r i s o n s of t h e J¢- a n d r~-values of crystalline with a m o r p h o u s p o l y m e r s t h u s enables us to conclude t h a t t h e e l e m e n t a r y shift of t h e ion f r o m one equilibrium position to a n o t h e r is c o n n e c t e d either w i t h t h e s t a t e of t h e m a c r o molecular s e g m e n t due to t h e ionic dipole forces of reaction, or has b e c o m e feasible only as a result of v a c a n c i e s of ionic d i m e n s i o n being c r e a t e d during s e g m e n t a l relaxation. CONCLUSIONS

(1) ] ' h e effects of plasticizer, e r y s t a l l i n i t y X a n d of e o p o l y m e r e o m p o s i t i o n s on e l e c t r o c o n d u c t a n c e y, ionic m o b i l i t y h- dipole r e l a x a t i o n period r, a n d dielectric c o n s t a n t c' were studied oll a t a c t i c p o l y s t y r e n e (PS), p e n t a p l a s t , a n d t h e e t h y l e n e (,opolymers w i t h v i n y l a c e t a t e (CEVA) or w i t h p r o p y l e n e (CEP). (2) T h e v a l u e of y was f o u n d to increase e x p o n e n t i a l l y w h e n a plasticizer of low p o l a r i t y was a d d e d to PS; this was due c o m p l e t e l y to t h e K change, while a polar plasticizer caused it to increase due to a s i m u l t a n e o u s increase of 1, a n d (tf c o n c e n t r a t i o n of t h e ions. (3) T h e y-decrease b y one p o w e r of 1/10 w h e n X increases, or w h e n t h e cont e n t of t h e second c o m p o n e n t was r e d u c e d in t h e e t h y l e n e c o p o l y m e r s was chiefly due to a 1c-decrease in t h e case of p e n t a p l a s t a n d C E P , b u t to a decrease of charge carrier c o n c e n t r a t i o n in t h e case of CEVA. (4) T h e r~ decrease during t h e P S plasticization, t h e decrease of t h e X of p e n t a p l a s t a n d t h e t e m p e r a t u r e increase of C E V A were all f o u n d to be a c c o m p a n i e d b y a n a p p r o x i m a t e l y equal increase of K in t h e highly elastic state; no d e t e c t a b l e ~c-change t o o k place w h e n r, r e m a i n e d t h e s a m e (for C E V A of various compositions at room temperature). Translated by K. A. ALLEX

1560

N.N.

MORC-UNOV e.t a[. REFERENCES

1. S. N. KOLESOV, Vysokomol. soyed. 6: 516, 1964 (Translated in Polymer Sei. U.S.S.R. 6: 3, 570, 1964) 2. G. P. MIKHAILOV, A. M. LOBANOV and D. M. MIRKAMILOV, Vysokomol. soyed. A1O: 826, 1968 (Translated in Polymer Sci. U.S.S.R. 10: 4, 959, 1968) 3. G. P. MIKHAILOV and B. I. SAZHIN, Vysokomol. soyed. 1: 29, 1959 (Not translated in P o l y m e r Sei. U.S.S.R.) 4. Yu. N. VAN-GAUT, Plast. massy, No. 5, 40, 1962 5. G. P. MXKHAILOV and B. M. FAINSHTEIN, Zh. tekh. fiz. 22: 759, 1952 6. L. E. A1KBORSKI, J. P o l y m e r Sci. 62: 331, 1962 7. S. SAITO and S. SASARE, Rept. Progr. Polymer Phys., J a p a n 12: 405, 1969 8. M. HATANO and S. KA1KBARA, J. Polymer Sci. 6: 232, 1962 9. M. HATAN0 and S. KAMBARA, J. Polymer Sci. 2: 1, 1961 10. I. A. MAIGEL'DINOV and K. I. TSYUR, Vysokomol soyed. 5: 243, 1963 (Translated in P o l y m e r Sci. U.S.S.R. 4: 4, 864, 1963) 11. P. H. HERMANS and A. WEIDINGER, Makromol. Chemic 50: 98, 1961 12. F. WlJRSTLIN, Kolloid-Z. 213: 79, 1966 13. R. A. TERTERYAN, M. B. KONSTANTINOPOL'SKAYA, Z. Ya. BERESTNEVA a n d V. A. KARGIN, Vysokomol. soyed. A l 1 : 2585, 1969 (Translated in Polymer Sei. U.S.S.R. 11: 11, 2940, 1969) 14. K. H. HELERS, Kolloid-Z. 190: 16, 1963 15. B. I. SAZHIN, V. P. SHUVAYEV and V. P. BUDTOV, Vysokomol. soyed., A I : 2393, 1970 (Translated in Polymer Sci. U.S.S.R. 12: 11, 2709, 1970) 16. B. I. SAZHIN, O. K. KHARITONOVA n a d V. P. SHUVAYEV, Elektroehimiya 4: 10, 1968 17. Spravoehnik khimika (Chemist's Handbook). p. 952, Izd. " K h i m i y a " , 1966 18. O. A. OSIPOV and V. I. MINKIN, Spravoehnlk po d i p o l ' n y m m o m e n t a m (Handbook of Dipole Moments). p. 83, Izd. "Vysshaya shkola", 1965 19. A. M. SIfKHOT1N, Voprosy teorii rastvorov elektrolitov v sredakh s nizkoi dielektricheskoi pronitsaemostyu (Theoretical Problems of Electrolyte Solutions in Media of low Dielectric Constant). p. 22, Gis. khim. izd., 1959 20. B. I. SAZHIN and V. P. SHUVAYEV, Vysokomol. soyed. A19: 730, 1968 (Translated in P o l y m e r Sci. U.S.S.R. 1O: 4, 846, 1968) 21. V. M. GAL'PERIN and V. P. SHUVAEV, E l e k t r o k h i m i y a 4: 714, 1968 22. B. JACHUM, A c t a phys. polon. 24: 785, 1963 23. R. BOYER, Perekhody i relaksatsionnye yavleniya (Transition and Relaxation Phenomena). A. Ya. Malkin, Ed. Izd. "Mir", 1968