PHYSICO-CHEMICAL BEHAVIOUR OF AQUEOUS AND NtONAQUEOUS SOLIimON OF AMPfiU^HOiIC

MOLECULES IN PRESENCE OF ADDTTIVES

MssmtAnoH SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS

FOR THE AWARO 6 F THE DEGREE OF

Muitn of t&I|thM(opiip IN

BY

KIR7I

DEPARTMENT OF CHEMISTRY ALIGARH MUSLIM UNIVERSITY

ALIGARH (INDIA) 1994

DS2433

PHONE ; (0571) 25515 DEPARTMENT OF CHEMISTRY ALIGARH MUSLIM UNIVERSITY A L I G A R H —202 002

Dated. ]>.9.:S1..

Dr. KABIR-UD-DIN P r o f e s s o r

The d i s s e r t a t i o n e n t i t l e d " P h y s i c o - c h e m i c a l

Behaviour of Aqueous and Non-Aqueous S o l u t i o n s of

Araphiphi l ic M o l e c u l e s i n P r e sence of A d d i t i v e s "

by Miss K i r t i , i s s u i t a b l e f o r s u b m i s s i o n f o r t h e

deg ree of Mas te r of Ph i l o sophy in C h e m i s t r y .

(KABIR-UD-DIN)

Bebttateb ^0 tl)E iHemorp of

(Late) PROF. H. N. SINGH

S-2-5-I-S-S-J-5

@ @ ( § » ^

Page

I n t r o d u c t i o n • . • 1

Expe r imen ta l . « . 18

R e s u l t s and D i s c u s s i o n . . . 20

Rere rences . . . 36

In complating t h i s d i s s e r t a t i o n I have been guided,

encouraged and advised by a numter of t e a c h e r s , s c h o l a r s ,

col leagues and f r i e n d s . I r e a l i s e the debt I owe to each of

them and 1 know tha t i f I were t o be deprived of the coope­

r a t i o n of even one s ing le person in t h a t pool of benefac tors ,

fhere would have taeen l e f t a very se r ious def ic iency in the

and product now before my r e a d e r s .

Special and profound thanks are due to Prof.Kaoir-ud-

Din, Deptt . of Chemistry, A.i-i.U., Al igarh . His q u a l i t i e s of

f r iendly guidance and int imate work r e l a t i o n s h i p with his

colleagues and s tuden ts are amply r e f l e c t e d in his supervis ion,

Ha encouraged me t o be f ree , innovative and bold in my inves t i ­

g a t i o n s . I t is d i f f i c u l t to say i f t h i s work would have oaan

poss iole without his c h a r a c t e r i s t i c overseeing and stewardship.

I aiii p a r t i c u l a r l y g ra te fu l to Prof. A. Aziz Khan,

Chairman, Dept. of Chemistry, for providing the necessary

research f a c i l i t i e s .

I am extremely beholden to my parents and a l l fa/ritly

memLsrs for t h e i r a f fec t iona te encouragement and i h t e r e s t

In my academic p u r s u i t s .

I must express my deep sense of g ra t i tude to my senior

co l league . Dr. sanjeav Kumar, for his pa t i en t and p e r s i s t e n t

sugges t ions , r e l a t e d to my labora tory work.

I would a l s o be f a i l i n g in my d u t y i f I do not

ment ion the c o n t r i b u t i o n of my f r i e n d s . Miss Krishna Kuraari,

Mis s Sara L i s David and a l l o t h e r f r i e n d s whose words o f

endearment and p r a i s e tept a l l f r u s t r a t i o n and d e f e a t i s m

a t a d i s t a n c e .

KIRTI

I N T R O D U C T I O N

1

The domain of surface science i s perhaps one of

the most in terd isc ip l inary areas of modem science and

technology . Although the importance of surface science has

been recognized for more than a century* i t i s only during

the la s t few decades that rapid advances in the understan­

ding of surface phenomena have taken place. When one looks

c loser to the earth, one finds that i t i s f u l l of o b j e c t s ,

and that each object i s surrounded by a surface or an inter­

face . Fortunately, a l l the i n t e r f a c e can be grouped in f ive

major c l a s s e s , namely, g a s / l i q u i d , l i q u i d / l i q u i d , s o l i d /

l iqu id , so l id /gas and s o l i d / s o l i d (Fig. 1) . All objects

are surrounded by one or more of these basic f ive interfaces .

All of these Interfaces have a common property ca l l ed surface

tension or surface free energy. There i s a c l a s s of compounds 2 3 ca l l ed surface act ive compounds * (or surfactants) that

decreases s t r ik ing ly the surface tension or surface free

energy of these in ter faces .

Surfactants, surface act ive agents, or detergents

are amphiphilic, organic or organometallic compounds having

two d i s t inc t parts , namely, a hydxrophilic (watet soluble)

or polar part, And « l i p o p h l l i c ( o i l soluble) or non-polar

part . The l ipoph i l i c part Is general ly a long hydrocarbon

chain. Depending on the chemical structure of the hydrophilic

moiety bound to the hydroi*iobic por t ion , the surfactant may

be c lassed as cat i o n i c , anionic, non i o n i c , or ampho ly t i c

(zwitterionic) . An exhaustive l i s t of both synthetic

o o

UNIVERSE

SUN EARTH

OBJECTS

MOON STARS GALAXIES

GAS

LlOmD LIQUID UQUID

GAS SOLID

LIQUID SOLID

SOLID SOLID

Fig. No. 1 The five inferfaces

3

and natural ly occurring surfactants Is available* Their

preparation and propezrties in general have been given in

the exce l lant monograph of Feildler and Pendler . Ttie

charac ter i s t i c propert ies of surfactants in so lut ion which

render poss ible t h e i r pract ica l appl icat ions such as washing

c l ean ing , wett ing, emulsifying, dispersing and foaming

depend in a l l cases on the tendency of these compounds to

accianulate at in ter faces between the solution and the adja-14 cent gaseous, l i q u i d , or so l id phases •

Surfactant molecules form assoc iat ion c o l l o i d s or

m i c e l l e s in so lut ion with in a f a i r l y narrow concentration

range. Micelle do not e x i s t at a l l concentrations and

temperatures. Tliere i s a very small concentration range

below which aggregation to mice l le i s absent and above

which assoc iat ion leads to mice l le formation* It i is concen­

t ra t ion i s c a l l e d c r i t i c a l mice l le concentration (CMC), The

number of molecules that aggregates to form mice l l e s i s

c a l l e d the aggregation number. Micel iar aggregation can be

demonstrated by measxirements of physical properties against

surfactant concentration. The most s ign i f i cant property i s

surface (or i n t e r f a c i a l ) tension (Fig* 2 ) .

The reason 'why do mice l l e s form' may be explained

by taking into account the changes occurlng i hen a monomer

i s transferred from i t s aqueous environment in to the

m i c e l l e . On transferring the monomer in to mice l l e , the

CMC

log (concentrotion)

F I 9 • N o . 2 * Surface (a i r -wa fe r ) tension os a function of surfactant

concentration for on aqueous miceHar solution. Schematic

structure of the solution is shown below and above the

crirical mic9liar concentration ( C M C )

:»

h i g h e n e r g y o f t h e h y d r o c a r b o n / w a t e r I n t e r f a c e I s l o s t ,

a s t h e c h a i n i s now i n c o n t a c t w i th o t h e r s of a l i k e

n a t u r e . T r a n s f e r of monomer i n t o m i c e l l e a l s o means t h a t

t h e s t r u c t u r i n g o f water around the hydrocarbon part of

the monomer i s l o s t , t h e r e f o r e an o r d e r e d s t a t e has become

a d i s o r d e r e d one w i t h regard t o t h e w a t e r , i m p l y i n g a

p o s i t i v e e n t r o p y change and a d e c r e a s e i n f r e e e n e r g y .

The f a c t o r o p p o s i n g t h e m i c e l l e f o r m a t i o n i n i o n i z e d s u r ­

f a c t a n t s i s r i s e i n f r e e e n e r g y due t o e l e c t r i c a l work and

t r a n s l a t i c n a l freedom l o s s e s due t o i n c o r p o r a t i o n o f monomer

in t o a m i c e l l e . T h i s d i s o r d e r t o o r d e r t r a n s i t i o n g i v e s

a n e g a t i v e e n t r o p y change %#hich w i l l oppose t h e p o s i t i v e

e n t r o p y c h a n g e s o c c u r i n g from l o s s o f water s t r u c t u r e , the

o v e r a l l d e c r e a s e i n f r e e e n e r g y due t o l o s s o f h y d r o c a r b o n /

water i n t e r f a c i a l e n e r g y and water s t r u c t u r e o u t w e i g h s

t h e f r e e e n e r g y r i s e due t o e l e c t r i c a l work and t r a n s l a ­

t i c n a l freedom l o s s e s , g i v i n g a remarkable t e n d e n c y t o

m i c e l l i s e . Mukerjee and M y s e l s have c o m p i l e d CMC data

of v a r i o u s c l a s s o f s u r f a c t a n t s u s i n g d i f f e r e n t t e c h n i q u e s .

Normal M i c e l l e s

Aggregate formed i n aqueous s o l u t i o n s o f s u r f a c ­

t a n t m o l e c u l e s a t CMC are known a s normal m i c e l l e s . They e q u i l i b r i u m ,

dre a lways in dynamic / Such m i c e l l e s are thought t o be 16 —18 r o u g h l y s p h e r i c a l ^°. A s c h e m a t i c two d i m e n s i o n a l

r e p r e s e n t a t i o n o f an i o n i c s p h e r i c a l - m i c e l l e i s shown

r,

In Fig. 3. In the case of ionic surfactants , part of the

counterions are "bound" to the surface of the mice l l e ,

forming vrtiat i s ca l l ed the "Stem layer", whereas the

remaining counterions are local ized at greater distances

from the surface of the mice l l e , inwhat i s ca l led the

"Gouy-Chapmann e l e c t r i c double layer".

Results of l ight scatter ing, v i s c o s i t y , diffusion

and ultracentrifugation studies on nonionic cetomacrogol

mice l les indicated the ir shape to be e l l i p s o i d a l with an 20 axial ratio of 2:1 . Some water molecules may be entraped

2 1 22 by the micelle and under certain circumtances part

of the hydrocarbon chain may extend into the aqueous 2"? I ^ a s e . The amount o f water i n t h e mice l i a r i n t e r i o r

v a r i e s from s u r f a c t a n t t o s u r f a c t a n t , but water i s c o n s i ­

d e r e d , at p r e s e n t , t o p e n e t r a t e t h e m i c e l l a r s u r f a c e o n l y

up t o d i s t a n c e s o f a p p r o x i m a t e l y t h r e e t o s i x carbon

21 23-25 atoms ' . The i n t e r i o r , or c o r e , of the m i c e l l e has

g e n e r a l l y been i n f e r r e d t o be h y d r o c a r b o n - l i k e from

2 6 2 1 2 7 e s r and nmr * s p e c t r o s c o p y and from t h e u t i l i z a t i o n

28 o f f l u o r e s c e n t p r o b e s

R e v e r s e M i c e l l e s

S u r f a c t a n t s in n o n - p o l a r s o l v e n t s , in t h e p r e s e n c e

of t r a c e s o f w a t e r , a s s o c i a t e t o form t h e ao c a l l e d

" r e v e r s e " or " i n v e r t e d " m i c e l l e s . The s l tructure of t h e

m i c e l l e i s r e v e r s e d , t h e p o l a r head groups of t h e monomer

—Stern layer

Gooy Chapman double loyer

P i g ' . 1 ^ 3 ' ^ two-dimensional schematic representation of the regions of a

spherical ionic micelle. The counteriops ( X ) , the heod group5(rj)) ,

and the hydrocorbon chains (^v^—) ore indicoted .

being present in the centre of the mice l l e , and the

hydrocarbon chains extending outwards into the solvent.

Such micel les could be formed in pf^sence of traces of

water v*iich forms a water pool in the interior of the

mice l iar aggregate. The s ize and properties of' reverse 2 9-32 mice l les vary with the amount of water present . A

possible structure of reverse micel le in a nonpolar

medium in equilibrium with monomer i s shown in Fig. 4.

The discontinuity in some physical property ( v i s ­

c o s i t y , s o l u b i l i t y , surface t e n s i o n , e t c . ) of the solution

can be used to identify the CMC, and techniques such as

scatter ing, ultracentrifugation and v i s c o s i t y are used to

determine the s ize and shape of the micel le . Some other

techniques which have been developed to determine the CMC

include dye solubilization"'-^ ••^*, water solubil ization^^,

nmr ' . The different experimental methods available

for determining the CMC are given in the compilations 17 18

of shinoda et a l , . Elworthy et a l . and Mukerjee and Mysels

Mixed Micelles

The formation of micel les from more than one

chemical species gives r ise to v4iat are known as mixed

mice l l e s . In the simplest case , binary or ternary mixtures

of surfactants of s imilar, but not ident ical chain lengths

may be studied and the thermodynamics of t h i s type of

^

M o n o m e r so lu t i on ( Ideal s o l u t i o n )

M ice l l e ( H y d r o c a r b o n po r t )

( N o n i d e a l s o l u t i o n )

FIG.fSlo REVERSE MICELLE

10

38 39 40

m i c e l l e formation has been descr ibed * . Cl int deve­

loped an a n a l y t i c a l descr ip t ion which Included both m i c e l l e

composit ion and oonotner concentrat ion above the mixed CMC

for mixtures of nonlonlc s u r f a c t a n t s . C l i n t ' s treatment

assumed Ideal mixing In the m i c e l l e . Furthermore, the

express ion of Lange and Cl in t * for the CMC va lues of

mixtures of nonlonlc sur fac tant s has been experimently 40,4

v e r i f i e d for c a s e s inhere idea l mixing might be expected The propeirtles of the mixtures of an anionic surfactant

A ^ A ^

and a nonlonlc surfactant ' , and c a t l o n l c and nonlonlc 44 s u r f a c t a n t s have been in terpreted with the aid of mixed

41 m i c e l l e formation between the s u r f a c t a n t s . Lange and Beck

and Cl in t pointed out that the CMC of the mixed m i c e l l e s

i s lowered more than that of the s i n g l e sur fac tant .

Another cl<iss of mixed m i c e l l e s r e s u l t s when low_

molecular weight molecules are s o l u b l l i z e d by m i c e l l e s

formed from s u r f a c t a n t s conta in ing a r e l a t i v e l y larger

non-polar cha in . The s o l u b l l l z e d subs tances , a l s o c a l l e d 45 a penetrat ing a d d i t i v e . may be located in the hydrocarbon

core or the hydrophi l lc mantle " .

Structural a spec t s of surfactant m l c e l l a r systemg :

Inf luence of a d d i t i v e s

Surfactant molecules can be considered as bui lding

b locks . Surfactant s e l f - a s s o c i a t i o n in aqueous media i s

s t rong ly cooperat ive and s t a r t s g e n e r a l l y with the

11

formation of roughly sf^ierlcal m i c e l l e s arovind the c r i t i c a l

m i c e l l e concentra t ion . When the surfactant concentrat ion

markedly exceeds the CMC, the shape of the spher ica l or

e l l i p s o i d a l m i c e l l e undergoes gradual changes *

Figure 5 schemat ica l ly shows var ious s t ruc tures that are

formed upon increas ing the concentrat ion of sur fac tant .

In the beginning of s t ruc tura l changes sF*ierical m i c e l l e s

become c y l i n d r i c a l , upon further increas ing the concen­

t r a t i o n , there i s a hexagonal packing of water c y l i n d e r s ,

Vpon addit ion of an o i l and a shor t -cha in a l c o h o l , one

can convert such water c y l i n d e r s in to w a t e r - i n - o i l

(w/o) rnicroemulsions*

I t i s p o s s i b l e t o induce a t r a n s i t i o n from one

s tructure t o another by changing the physico-chemical

c o n d i t i o n s such as temperature, pH, addi t ion of ion ic and 18 52—58 nonionic s o l u t e s , in the surfactant s o l u t i o n ' . The

rod shape s tructure f i t s the r e s u l t s f o r dlmethyldodecyl 54 amineoxide m i c e l l e s in s a l t s o l u t i o n s at low pH va lues

For ion ic surfactant sys tems, m i c e l l a r growth increases

very s trong ly with decreasing temperature, with increas ing

counter ion s i z e ( c l " , Br ' , I~) and with the addi t ion of 5 5-57 s a l t s . For nonionic m i c e l l e s , r a i s i n g the tempera-

58 ture favours m i c e l l a r growth .

Since m i c e l l e s are dynamic s t r u c t u r e s comprising

a l i q u i d c o r e , i t i s probably u n r e a l i s t i c to regard them 59

as r i g i d s t ruc tures with a p r e c i s e shape . The shape

^h

li.

o to w z ° i^ O O 2 < — Q- d

>-_. ^ < ^ z °^

>< UJ I

z o — to

1

c r - C o

CO •>-'

( u L O D ^

^ L. U D D l/ L-

•^ t ; (/) O

w c 3 O o Z i_ O o •-C *-" > c

CJ

° ^ ^ o C o o

• ^ 0 )

O JZ

6 - l_

o en >*- c

l_ O

o c « • - • " "

§ 1 _ d *- D O »- C

:;; 2 r ) "*-• d D —' —.

o u '

•*^ •*->

o c E o

01 L. D

< 01

2 LU o a to

o"

LL

13

and s ize of these mice l iar aggiregates can^ln principle^ be

determined by various methods, such as l ight scat ter­

ing , di f fusion, sedimentation v e l o c i t y , sedimentation

equilibrium * , ultrasonic absorption^^, time resolved 66 67

fluorescence * , e t c . Viscometric technique has been used In a number of experimental Investigatlons^^'^^'^^*^'^ of micellar solutions both because of i t s siroplicity and

i t s s e n s i t i v i t y to detect changes in the s ize of the

anisotropic micellar aggregates. The sphere-to-rod tran­

s i t i o n s of ionic and nonionic mice l les have been studied

by a number of workers^°'^^'^^"^"^ •^^"''^. For sodium

dodecyl sulphate and for a ser ies of catlonic surfactants

in Nacl so lut ions , a sharp break in apparent micelle

molecular weight i s observed when the Vacl concentration

reaches a value of 0,45 M and the break point would 72 73 correspond to the sphere-to-rod trans i t ion * . The

micellar sphere-to-rod transi t ion i s highly dependent

upon the nature of the counter ions and was concluded

that strong counterion binding promotes the trans i t ion

from small si*ierical to cyl indrical mice l les ' .

Temperature a f fec ts the sphere-to-rod trans i t ion .

The v i s c o s i t y of the cyl indrical micellar solution dec­

reases with the increase in temperature due to the break-57 Ing up of the cyl inders to smaller aggregates . Decrease

in micellar s ize with temperature at high concentrations

of e l ec t ro ly te s has been reported by various authors * *

14

Importance of Mice l i ar Solutions

Hicellar solut ions are known to increase the solu­

b i l i t y of s l i g h t l y soluble or insoluble organic compounds 13 18 in water ' . Mice l iar solutions are used extens ive ly in

synthet ic , analyt ica l , i*iarmaceutical and industrial che­

mistry* The change in the micellar structure have pronoun-77 ced e f f ec t s on micellar ca ta ly s i s . Several reports on

the structures of micel les of cetyltrlraethylammonlum

bromide (CTAB) have recently appeared * , and t h i s

micel le has been used to catalyse a variety of react-. 77-79 ions

The engineering applications of surface science

range from agricultural sprays to o i l recovery Including

areas such as c a t a l y s i s , coating, dispersions, e l ec tron ics ,

f loatat ion of minerals, lubrication, and retardation of

evaporation from lakes and reservoirs .

Among biomedical areas, the applications of surface

science extend from anesthesiology to zoology Including

f i e l d s such as a r t i f i c i a l implants, biomembranea, b io -

lubrication, l ipoprote ins , lung surfactant, opthalmology,

pharmaceutical and pharmacology. The surface active agents

may influence the biological e f f icacy of the drug or pes­

t i c i d e . Many poorly soluble drugs and pest ic ides are

administered in a solubll lz«d form using micellar solutions

in order to increase the b ioava i lab i l i ty and targett ing to

the s i t e of action, certain surfactants have the a b i l i t y

If)

to Increase the permeability of some bacterial c e l l wal ls ,

and hence are synergist ic with some antibacterial agents.

Micellar solut ions in reverse mice l les play a

v i t a l role in removing polar dirt from c lo thes , in motor

o i l s to so lubi l i ze corrosive oxidation products and to

prevent them firora reacting with engine parts. Solubilized

systems are used in removing odour causing molecules from

food packaging plants , photographic processes and in

surfactant type corrosion inhibi tors . A very important

application of micel lar solution i s in separation 80 science . Aqueous micellar systems have the a b i l i t y to

s o l u b i l i z e , compartmentalize and concentrate (or separate)

so lu te s , a l ter the local environment about associated

so lu te s , a l ter the posit ion of equilibrium systems and

alter the photophysical and chemical pathways and rates

among others. Although a l l of these micellar features can

be exploited to aid the separation s c i e n t i s t in spec i f ic

instances, the main basis for the successful u t i l i z a t i o n

of aqueous micel lar media in separation stems from the

fact that they can d i f f e r e n t i a l l y so lubi l i ze and incor­

porate a variety of so lu tes . Some of these are micel lar

f a c i l i t a t e d sampltlag considerations, extractions based

on the d i f ferent ia l so lubi l iz ing a b i l i t y of mice l l e s ,

micellar Electrokinetic capi l lary chromatography, micellar

liquid chromatograi*iy, micellar enhanced detect ion.

In

micellar enhance u l t r a f i l t r a t i o n , and micel le mediated

extract ions or preconcentrations of polyaromatic hydro­

carbon.

I t i s c lear from the above mentioned l i terature

that micellar media have attracted wider attention than

any other media in recent years, with speci f ic and judicio­

us choice of media, chemical transformations can be

carried out more swi f t ly , under milder conditions with

higher yie lds and fewer by-products and, if necessary,

with good stereo and regio-chemical control .

Importance of ftesearch Problem

Increasing attention i s being devoted to the study

of the "incorporation" or so lubi l izat ion of neutral organic

molecules into micel les in aqueous solut ions . Some of the

most studied so lub i l i za tes are a lcohols , because of the 81 important role they have in preparation of microemulsion

I t i s generally accepted that the medium chain length

alcohols intercalate between the surfactant ionic head 82 groups to decrease the micellar surface charge density .

This e f fec t i s correlated with modification of the growth 83 and shape of the mice l les . Recently some linear medium

chain al iphatic amines have been gett ing more recognisation

as cosurfactants in microemulsion preparations . Des­

p i te the significance of amines in microemulsions proper

attention has not been paid so far to the contribution of

17

medium chain normal amines In mlcellar systems.

Visualizing the significance of mlcel lar structure

trans i t ions and the ir dependence upon the nature of e l e c -87 88 t r o l y t e s ' , temperature and, in some c a s e s , the Influence

8 9 of org'inlc additives , i t was thought worthwhile to

persue a study of the e f fec t of a l iphat ic amines on concen­

trated mlcellar solutions in aqueous potassium bromide

(KBr). Compared with other techniques, the capi l lary v isco-

metry method i s simple and re l iab le and can provide a

large body of Important information with respect to the 90 invest igat ion of the Increase in micel le s ize . The results

of studies on the ef fect of the addition of various a l i ­

phatic amines on the v i s c o s i t y of 0,1 m CTAB + 0.1 m KBr

solutions are presented herein. Prom the temperature depen­

dence of the v i s c o s i t y , the act ivat ion free energies (A-G*) >

enthalpies ( A H ) and entropies (AS*) for the viscous

flow have also been calculated.

E X P E R I M E N T A L

1 ?

(a) Mate r ia l s :

Cetyltrimethylaramoniifln bromide (CTAB) from E. Merck

(98.5%) was r e c r y s t a l l i z e d twice from acetone,

CH2(CH2)j 5 N'''(CH3)3Er"

Ttie surfac tant was dr ied a f t e r f i l t r a t i o n in a hot a i r oven

at 50 c. The pu r i ty of the surfac tant was ascer ta ined from

the absence of minimum in the surf^^ce tens ion versus loga­

rithm of concent ra t ion p l o t s . KBr from E. Merck was heated

for one hour (rJeO c) and was kept in a des icca tor (^2^5^

t i l l use.

The amines, v i z . n-hexylamine (CgNH2)» n-heptylamine

(C7NH2) and n-octylamine (CgNH2) ( a l l "Purum grade") were

obtained from Fluka, vrtiilst n-butylamine (C.NH2) was a

R iede l -de^aen product . All chemicals were used as supplied.

Demineralized water, r e d i s t i l l e d from a lka l ine potassium

permanganate, was used. The speci f ic conduc t iv i ty of water

was in the range IxlO" to 2xlO~ ohm" cm" . Water, equ i ­

l i b r a t ed with atmospheric carbondioxide, was used throughout

the work.

(b) Prepara t ion of so lu t ions ;

0 .1m CTAB in 0,1 m KBr so lu t ion was prepaired by

dissolving required amounts of CTAB and KBr in a s ingle

volumetric f l a sk in d i s t i l l e d water. The concent ra t ion of

mixed solvent was f ixed throughout the work. Different

ID

so lu t ions of amines were prepared in the mixed solvent

(0.1 m CTAB + 0.1 m KBr) and the concen t ra t ions of amines

were ca l cu l a t ed as mol per kg mixed so lven t .

(c) v i s c o s i t y measurements :

v i s c o s i t i e s of the so lu t ions were measured in an

Ubbelohde viscometer immersed in a thermostated bath. The

r e l a t i v e v i s c o s i t y of a solut ion was ca l cu l a t ed using the

r e l a t i o n :

-t „ _t_ . . . . (1) % ^o

where n and "n are the v i s c o s i t i e s of the so lu t ion and

water, r e spec t ive ly , at the experimental temperature an<3

t and t are the respec t ive flow times for the same volume

of so lu t ion and water. Density co r r ec t i ons were not made

since i t was found t h a t these were neg l ig ib le . The solvent

flow time was always longer than 200 seconds. At leas t four

flow-time measurements were made at each concent ra t ion and

a mean deviat ion from the mean of a l l measurements not

exceeding 0.1 second was required. The temperature of the

bath was con t ro l l ed to an accuracy of + O.l^c. The measu­

rements were made at 30° . 35^, 40° , 45°C.

RESULTS AND PISCUSSION

: n

The effect of add i t ion of KBr on the r e l a t i v e v i sco-

c i t y (i\/%^ °^ 0.1 m CTAB solut ion at 3O3.I6 K i s i l l u s t ­

ra ted in Fig. 6. vJhen a s a l t i s added to a sur fac tan t

so lu t ion and i t s concent ra t ion reaches a threshold v a l u e ,

non spher ica l mice lies.form because the presence of s a l t ions

near the polar heads of the surfac tant molecules decrease

the repuls ion force between the head groups. A reduction in

the repuls ion makes i t j jossible for the sur fac tant molecules

to approach each o the r more c lose ly and form larger aggre­

gates which requires much more space for the hydrophobic

cha ins . This leads to a sharp r i se in T^A^p; in the present

system (of 0.1 m CTAB) i t occurs around 0.1 m KBr indica t ing e g Q 1

the formation of l a rger aggregates ' (rod-shaped micel les) :

t h i s being the reason of choosing 0,1 m CTAB + 0.1 m KBr

system for the de t a i l ed study of the e f f ec t of n-alkylamines

and temperature.

Figures 7(a) to (d) show the v a r i a t i o n of 't^Au with

concent ra t ion of added amines at 3O3.I6 K, 308.16 K, 313.16

K and 318.16 K. v i s c o s i t y data for d i f fe ren t amines at

d i f fe ren t temperatures are given in Table I . Data in Table

I and Figures 7(a) to (d) indica te t ha t the addi t ion of an

amine may e i t h e r decrease or increase the v i s cos i t y of

s t a r t i n g so lu t ion (O.i m CTAB + 0.1 m KBr). I t i s fu r the r

seen t h a t the increase or decrease of v i s c o s i t y depends upon

the chain length and the nature of added amines. With Cg,

C7 and Cs-amines, the v i s c o s i t y f i r s t r i s e s abruptly followed

21

30.0 -

24.0 -

18.0 -

12.0 -

6 0 -

0 .0 0.0 O.OA 0.08 0.12

[KBr ] (m)

0.16 0.20

F ig . N o . g : Effect of K B T concentrafion on fhe relative viscosity

of 0.1m C T A B micellor solution at 303.16 K.

' ) 0

T a b l e - I

R e l a t i v e v i s c o s i t i e s of 0 . 1 m CTAB + 0 , 1 m KBr i n p r e s e n c e of n - a m i n e s a t d i f f e r e n t t e m p e r a t u r e s .

Amine Amine c o n c e n ­t r a t i o n

( m o l . k g )

R e l a t i v e v i s c o s i t i e s

l°cT 30 35

InS^L

40 45

n-But y l i m i n e 0 . 1 0 0 0 .150 0 . 2 0 0 0 . 6 0 0

77 79 56 31 39

2 , 1, 1, 1, 1.

82 43 38 23 36

1. 1. 1, 1. 1.

94 31 28 22 35

1, 1. 1. 1. 1,

48 22 20 19 34

0.700 1.40 1.38 1.37 1.35

n - H e x y l a m i n e 0 . 0 2 0 0 .050 0 .100 0 .175 0 .250 0 . 3 5 0

6 . 6 9 8 . 0 7 5 . 2 9 3 .65 3 .18 2 . 9 7

,76 ,29 .75 ,73 .79 .89

1, 2. 2, 2, 2

81 67 67 50 54

1. 1. 2, 2, 2,

64 91 04 09 34

2.72 2 . 5 7

n - H e p t y l a m i n e 0 . 0 2 5 0 . 0 6 0 0 . 0 7 5 0 . 1 0 0 0 .125

3 1 . 6 0 115 .02 117 .20

9 7 . 1 4 4 5 . 1 0

12 46 48 47

,80 ,09 ,85 ,91

5 16 22 23

91 49 13

,84 1 7 . 3 6 11 .96

3 . 3 3 7 . 6 4

1 0 . 6 9 10 .99

7 . 9 0

n - O c t y l a m i n e 0 .010 0 .020 O.O3O 0 , 0 4 0 0 . 0 6 0 0 . 0 7 5

11 .85 73 .52

2 5 9 . 9 9 5 3 2 . 8 4 6 7 8 . 5 8 1 9 0 . 6 9

5 20 30

131 251

10 ,70 86 78 47

2, 8.

10. 35. 89 .

77 74 33 90 90

1 4 4

13 37

91 26

,18 05 82

1 7 5 . 8 6 135 .83 8 4 . 9 4

23

7 0\-

6 0

5 0

4 . 0

3 0

2 0

1 O

0 OL

Q ~

m ~ <g) -

o -

C4NH2

C6NH2

C7NH2

C8NH2

0.2 0.3 0.4

[ n - amines] (m)

0,5 0 .6 0.7

Fig. No.7(oX'--090''ifhms of relotive viscosities of 0 . 1 m CTAB -l-0.1mKBr

solutions OS a func t ion of added n-amines at 303 .16 K .

2 ;

7.0

6 .0

0.0 0

e #

<s o

C4NH2

C6NH2

C7NH2

C Q N H 2

0.1

Rg.Na7(b)

0.2 0 3 0.4 0.5 0.6 0.7

[ n - amines J ( m)

Logarithms of relative viscosities of 0.1 m CTAB + d m KBr

solutions OS o function of added n - a m i n e s at 308 .16 K

o

C4 NH2

Cg NH2

C7 NH2

C 8 N H 2

0 2 0,3 0.4

( n - amines ] ( m)

0.5 h.6 0.7

Fig.NCxT (c) • Logonthms of relotive viscosities of 0.1m C T A B - h 0 . 1 m KBr

soluf/on OS a function oi added n - omines ot 313.16 K

5.0 Q C4NH2

# C6NH2

C7 NH2

O CQ NH2

0 2 0 3 0 4 0 5 [ n - omines] (m )

0 6 O 7

Fig .rsio.7(d) . Logarithms of relafive viscosiries of 0 1m C T A B + O l m KBr

solutions OS a function of added n -am ines at 318 16 K

Z l

by decrease in v i s c o s i t y . The e f fec t was p rog re s s ive ly more

pronounced f o r C , and Cg amines. In case of C^NH2/Viscosity

decreases r igh t from the beginning. The v i s c o s i t y increments

a t low concen t r a t i ons of h igher amines (Cg-Cg) can be i n t e r ­

p re t ed in terms of the formation of large mice l l e s owing

to t h e i r s o l u b i l i z a t i o n / i n c o r p o r a t i o n in to the m i c e l l e s .

The decrease in the v i s c o s i t y on a f u r t h e r add i t ion of these

amines i s a r e s u l t of the breaking of l a r g e r mice l l e s in to

small aggrega tes . Addition of C^NHj r e s u l t s in breaking of

i n i t i a l l y presen t rod-shaped mice l l e s t o sphe r i ca l with a

concomitant decrease in the v i s c o s i t y value comparable t o

g lobu la r mice l l a r s o l u t i o n . The preceding d i scuss ion r e f l e c t s

t h a t l a r g e r amines s o l u b i l i z e p r e f e r e n t i a l l y in m i c e l l a r

so lu t ion and lower the surface charge d e n s i t y which i s r e s ­

pons ib le fo r m i c e l l a r sphere - to - rod t r a n s i t i o n . Fur ther

add i t ion of the amine beyond the optlmun concen t r a t ion

a f f e c t s the water s t r u c t u r e predominant ly , r e s u l t i n g in the

breaking of g iant aggrega tes to r e l a t i v e l y smal ler ones and

hence a gradual decrease in v i s c o s i t y i s observed. The

behaviour of C^NH2 d i f f e r e n t than o t h e r s i s due to the

hydroph i l i c nature of t h i s amine, i t i s p a r t i t i o n e d more

in the aqueous phase; hence t h i s a f f e c t s the water s t r u c t u r e

and causes the breaking of i n i t i a l l y p r e s e n t large m i c e l l e s 92

in the so lu t i on . Such t r a n s i t i o n s from rod- to - sphere by

the a d d i t i o n of lower a lcoho ls t o dodecyl t r imethyl ammonium

bromide-sodium s a l i c y l a t e mice l l e s have been repor ted from

28

93 l i g h t s c a t t e r i n g m e a s u r e m e n t s

F i g . 8 shows t h e I n ( ' ' lA^) v s . 1 / T p l o t s f o r d i f f e r e n t

c o n c e n t r a t i o n s of h e p t y l a m i n e ( s i m i l a r t y p e of p l o t s were

o b t a i n e d f o r o t h e r a m i n e s ) . The o b s e r v e d l i n e a r i t y o f t h e

p l o t s shown i n F i g u r e 8 i s i n t e r p r e t e d i n t e r m s of t h e

r e l a t i o n

In T^/TJJ^ = I n A + A G * / R T . . « . (2 )

where A i s a c o n s t a n t and ^G* i s t h e a c t i v a t i o n f r e e e n e r g y

f o r v i s c o u s f l o w . As d e n s i t i e s o f t h e s o l u t i o n s were c l o s e

t o d e n s i t y o f w a t e r , k i n e m a t i c c o r r e c t i o n s were n e g l e c t e d ,

and v a l u e s o f /s^G* were c a l c u l a t e d f rom t h e s l o p e s of t h e s e

s t r a i g h t l i n e s shown i n F i g u r e 8 . As s t a t e d e a r l i e r , ^^.A^

were o b t a i n e d o n l y a t f o u r t e m p e r a t u r e s i n t h e r a n g e of

30 t o 45*^C. The l a c k of more e x p e r i m e n t a l d a t a p o i n t s d o e s

n o t p r e c l u d e i n o b t a i n i n g good c o r r e l a t i o n c o e f f i c i e n t s ( r ) .

E s t i m a t i o n of a c t i v a t i o n p a r a m e t e r s a r e , t h e r e f o r e , s u f f i ­

c i e n t l y a d e q u a t e . The r a n d c a l c u l a t e d / \ G * v a l u e s a r e

shown i n T a b l e I I .

U s i n g t h e G i b b s - H e l m h o l t z e q u a t i o n

3 ( ^ i G * / T ) / a ( l / T ) - A n * . . . (3)

alongwith the dependence of A<2* on T (Figure 9), the a c t i ­

va t ion en tha lpy (AH*) for the v iscous flow was c a l c u l a t e d .

The /^H* values r e f l e c t the energy used in the r o d - t o -

sphere t r a n s i t ion-When the temperature i s increased by a

2'I

6.00 F

4.00h

c

2,00U

0.0(>

0.060m) (0.075 m)

(0 lOOm)

(0 .125m)

( 0 . 0 2 5 m )

(0 .00m)

X X 3.10 3.20

1/T(10'^K~S 3.30 3.40

F ig . No . 8 ; Voriofion of Ln(n./n.o) with 1/T for 0.1 m CTA8-»-

0.1 m KBr solutions in the presence of various

concentration of n - heptyl amine maintioned in ( )

30

small value dT the t o t a l energy added to the system i s

Cpdt, where C i s the heat capacity at constant pressure.

This amount of energy w i l l p a r t i a l l y be spent on "evaporating"

some of the amphii*iiles previously attached to the mice l l e s .

At high temperatuire these evaporated surfactant molecules are

unable to remain in s o l u t i o n , so i t i s a necessary consequence

that they form new m i c e l l e s cons i s t ing of a smaller number

of monomers. This mechanism i s involved in t rans i t i on of

rod-shaped mice l l e s to spherical ones at e levated temperatures.

The obtained AH* values (from Figure 9) are also

given in Table I I . The values of /^G* and A.H* show that

^ H* covers the t o t a l contribution to zi G* and, therefore,

the entropic contribution i s n e g l i g i b l e . I t may be noticed

that the observed l i n e a r i t y in the In ifjA o v^* /" p lo t s

(Figure 8) indicates that enthalpic contribution to AG*

i s independent of temperature.

Figure 10 shows the variat ion of ^H* with concen­

trat ion of added amines. From Table II and Figure 10, i t

may be seen that Z G* and AH* values are highly dependent

on the nature and concentration of added amines. The higher

values of ^H correspond to the formation of larger aggre­

gates (elongated rods) , and low values towards the smaller

aggregates (spherical m i c e l l e s ) . The magnitude of ^O*

and AH* for different amines indicates tha^ higher chain

length amines are capable to induce the growth process of

I

XI

C

o •H .

^ ^

^ ^

PQ

o

^ c - ' O

» -H O 4J

nj + -H CQ (0 < >

m E d)

C

o

o o

(0 l-i

O

m 4J

H C > 0)

^

^ ^

U 0) o o

0) C

•H (0

c u V O

0) 0) •H 4)

o» c

C § O I

O V 4) M-i

c o

o c •

4J « '

> u •H a x : o c -H

c o o

o 1 - 4

0)

o * -

c

«

«o l-(

* CO rH CO

:><

VO r-l • ro •-» ro

i>C

VO 1-t

• 00 0 m

i<i

VO 1-1 • n 0 m II

1

u:. ro ^ i-H

• ro

rH 1 >< ^ ro c t-«

• ro

r-«

1 u; tn V 0» ro

rH 1 u: Ov Ov CM • ro

n ro 0

c o

4J ^ 10 (0 I

*J -H ^

O 5 c o *« u o

o E

f-i ro r- ro <N CTv 00 'a* 00 r^ f^ <H Ov ON 0> CD CT> (TV <7> <7\ Ov OV CT' Ov

• • • * • • o 0 0 0 0 0

t-H

CO 00 •

If)

r-r-

t ro 0

Tf Ov 00

r CM in

CM rH Tj-

Tf 00 00

^ r-r-

00 ro 0

ro ov 00

r-CM in

r-o (TV

VO VO

•* ro o o o

ro

Tf ro o O O

i n r- VO «-H VO CM CO ^ i n r-O CM -^ VO O " ^ i n • * CM CN» CM >-• o o o

• • • t • 0 0 0 0 0

0 CM OV

ro

0 r-Ov •H

0 CM 0 CM

0 CM ( rH

0 r-ev CM

0 • *

0 ro

o o o o

0 0 0 0 0 C7V VO Tp "«r 00 VO ^ O O t-H CM CM CM ro ro

* • * • • 0 0 0 0 0

0 r-ro 0

0 r in ro

0 00 tH

ro

0 CO 0 CM

0 0 in ro

0 ^ CM ro

0 0 0 0 0

0 CM VO in

CM CM 00 in

0 CM V TT

0 00 VO CM

0 00 CM ro

0 00 ro ro

0 0 0

in 00 CM (M 00 VO Cv CM Ov ov in r-Ov Ov Ov CO ov ov 0\ o\ &i o^ &> (y\ 31 0

Ov CO rn

0

CM r-ro

0

ro (N CM

0

i-H

in t

0

in r 00

0

ro r-'j'

• •

T5 V C 0 u

CD 00 CM VO ro

in t-H <-H CM ro ro 00 c CM in r» r-' c^ n cvi r* 00 ^

CO 00 CM VO r o <-•

5 in

m ov

in in • CM <^

in 0 in t-H

VO

CM 00 c ro ro

ro ov ^ C7V rH

CM f-H

"T

r-0 0 0 0 0 0 0

o o o o o o ^ r*' ro r« o ^ ov ^ t-i ro i n •* ^ VO r - r^ CO crv 0 0 0 0 0 0

o o o o o o ^ CM CM m CM O ov CO CO »-• ro O i n Ov Ov Ov ov o

• • • « • • O O O O O -H

0 0 0 0 0 0 ^ VO CM ^ VO tH CM m CM O CM VO ro •* ro o O O

0 0 0 0 0 0 •H CO in in VO ro o 00 VO c^ in in

<T> O VO CM fH O

i-H CM t-H ^H t-H r H

0) c •H i rH >t iJ 3 m c

0 0 rH •

0

0 in t-H

• 0

0 0 CM •

0

0 0 VO «

0

0 0 r-•

0

V

^

i r-l >. X 0) X f c

0 CM 0 •

0

0 m 0 •

0

0 0 •H •

0

in

r» rH •

0

0 tn Ci •

0

0 in ro •

0

o> • o\ ON • o

o a\ (T> o • o

o r-a\ a> • o

»H ON

o Ot • o

r~-'* 00 a> • o

o m M" u^ r~ \o 00 •* •-< 00 c> o^ O^ <7 CO C^ <T* CO cr (7N o^ o^ ci o^ o o o o o o

22

m vo in •

00 CM

t-H

CO ON •

• *

m

•*»•

^ «t • o m

CO o f-• r-OJ

0^ <«)• •«3"

• t->

fN)

O ^ m

ro CM

n n ON

if) m

in ON

vo ^ in

vc CN in

r-

^ • *

o r-ro

in r-t CN

o t-H

r-( VO in

CO <N

in r~ c ««f ro

1 •xr t

o fO

in .-« 1

r-<N

00 ^ ^

»-« (N

c n ro

en <NI

I O) CTi

in ro

vo Ov vo 1-<

in

vo (N in

r ij-

o •««'

o r-ro

r tH

CM

O >H

00 ^ r-ro •*

(N O vo r-

ro fN

m in

on Tf a m

Tf C r-o

vo Tf

r .-1

.H CO o CO

t 1-1

o vo

r-i-i

Ov oo

r-t '* VO CO

f-t

• ^

»H in

<N CM

o o o o o n ro cjv o t^ O f^ vo (TV vo CM o ro n o

•H CM (N (N <N

o o o o o o vo o o o rn o ^ in ro r ro • vo 'V ^ in vo ^

•-• <*M C N ro

o o r-r-

o CN

o CO

o r-Ov o

o o r-»H

o o 00 Tt

o o CN o •

o r vo •

o in ro ro •

o o CO in •

o ^

•

o o r-4

• CN ro ro CN OJ CN ro

o o c • *

o o ro CO

O CO 00 00

o OV vo CO

o o in 00

CN ro ro ro (N

O O o O O O o o <y> o r- o\ ro ro CN CO CN vo vo o ^ CD in «-«

r-i ro ro ^ in in

o o o o o O O O vo CO in ^ vo r* o ^ r^ t^ in CO ro ro

o ro r-

o o (TV CN

O o vo in

O CO r CN

o o (N in

o o in CN

CN ^ in VO VO in

M

•-t

T3 C

o

•H

e >i in o in o 4J CN vo r^ O 0 . 0 0 0 - ^ 4) • • • •

as o o o, o

in CN

0) c

r-* o o o o o in >« rH CN ro '<f in ( *j o o o o o o u • • • • • • o o o o o o o

33

12.00-

10.00-

\: 8 0 0 -

>a>

o u

O

•^

o ^

( 0 . 060 m)

(0 .075m)

( 0 . 0 2 5 m )

(0.100m)

6 00

(0 .125m)

(0 0 0 m )

ooL _L 3.10 3.20 3 30

l /TdO^K S 3 4 0

Fig. No . 9 : Gibbs- Helmholfz plots for 0 1m CTAB-»- 0 1 m KBr m fhe presence of various concentrafion of n-heptyl amine mentioned in ( )

34

I o o

<]

56.0

42 0

14.0

0 0

n -• -

® -O -

C4NH2

C6NH2

C7NH2

C8NH2

0.2 0 4

[ n - amine J (m)

:SL 0.6 0.8

F i g . N o , 1 0 ; Voriofion of activation enthalpy ( A H * ) for the viscous flow

of 0.1 m CTAB H- 0,1 m KBr solutiorvs as a function of odded n-amines

3r)

mice l l e s upto a optimum concentration, beyond which a solvent

structure comes In p ic ture . While the low values for A H*

for C-NHo show that the water structure factor plays an

Important role with hydrophlllc addit ive with a concomitant

breaking of larger aggregates. The behaviour of these amines

Is due to the combined e f f e c t of two opposite e f f e c t s , namely^

part i t ion ing in mice l lar phase and part i t ioning in bulk

solvent . At higher concentrations the l a t t e r e f f ec t plays

an Important role in breaking the larger aggregates.

R E F E R E N C E S

3r,

1. V. Ramamurthy, Tstrahadron Report No, 211, T&trahedron,

£3 , 5753 (1986) .

2. J.W. Mcaain, • 'colloid 3019009", D.C. Heeth and Co.,

Boston, 1950.

3. W.C. Pres ton , j . Phys. and c o l l o i d Chem., 52, 84 (1948),

4 . G.S. Har t l ey , "Aqueous s o l u t i o n s of Pa ra f f in chain s a l t s " ,

Hermann, P a r i s , 1936.

5. J .K. Thomas, "The Chemistry of Exc i t a t i on a t I n t e r f a c e s " ,

American Chemical Soc ie ty , Washington D . C , 1984.

6 . W.L. Hinze, in "Colloids and Sur fac t an t s i Fundamentals

and App l i ca t ions" , -Sditad oy E. Burni and S. P e l i z z a t t i ,

soc i e ty Chemica I t a l i a n a , Rome, pp. 167-207, 1987.

7. P.H, Elworthy, A.T. Florence and C.iJ. Macfarl^ne, in

" S u l u o i l i z a t i o n by Surface Active Agents and i t s Appli­

ca t ions in chemistry and Bio log ica l s c i e n c e s " . Chapman

and H a l l , London, 1968.

8. M.J. Shick, J . c o l l . SCi . , r 7 , 801 (1963) .

9. M.J, schwuger, j . Am, Oi l Chem. S o c , 59., 258 (1982).

10. J . Leja , "Surface Chemistry of Froth F l o t a t i o n " , Plenum,

New York, 1982.

1 1 . R.H. O t t a w i l l , in "^^onionic S u r f a c t a n t s " , Edited by M . j .

Shick, Dekksr, New York, 1967,

12. P. ^*ukh^rJaa, in "Solut ion Chamistry of S u r f a c t a n t s " ,

Edited by K.L. M i t t a l , Plenum Pre s s , Naw York, 1979.

3

1 3 . J . H , Pand l a r and 3 . J . F e n d l a r , • ' C a t a l y s i s i n M i c e l l a r

and M a c r o n o l a c u l a r Systems'*, Acadamic P r a s s , I n c . ,

New York, 1975 .

14. M a r t i n j . S c h i c k , ( a d , ) , • •^^nionic S u r f a c t a n t s P h y s i c a l

Crjemistry'*, Marce l Dakkar, I n c . , New York, 1987,

1 5 . P . Mukerjae and K . J , M y s e l s , " C r i t i c a l M i c e l l a concen­

t r a t i o n s of Aqueous S u r f a c t a n t S y s t e m s " , NSRDS-NB3 36,

s u p e r i n t e n d e n t of Documents, Washington , B . C . , 19 7 1 ,

16 . K . J , M y s e l s , " I n t r o d u c t i o n t o c o l l o i d c h e m i s t r y " . I n t e r , ,

P u b . , Naw York, 1959.

17 . K, Sh inoda , T. Nakagawa, B. Tamaroushi, and T. Isemura

" C o l l o i d a l S u r f a c t a n t s % some P h y s i c o - c h e m i c a l P r o p e r t i e s

Academic P r e s s , New York, 1963 ,

1 8 . a, Llndmann and H. Wannarstrom, " M i c e l l e s " , Topics in

C u r r a n t Chemis t ry , Vol 87, P . 5 . S p r i n g e r - V a r l a g , Bar l l ry '

Haideloarg/New York, 1980; Y. C h a v a l i a r and T, aaroo,

r e p . P rog , P h y s , , 5_3# 279 ( 1 9 9 0 ) .

1 9 . S, C a p o n e t t i , D. C h i l l u r a ^ ^ a r t i n o , M.A. F l o r i a n o , and

R. T r i o l o , J . Am. Cham. s o c . , 9., 1193 ( 1 9 9 3 ) .

20 . CIS. M a c f a r l a n a , K o l l o i d - z , Z. Polym. , 2 39 , 682 ( 1 9 7 0 ) .

2 1 . J . C l i f f o r d , and a .A. f ^ t h i c a . T r a n s . Faraday S o c ,

6 1 , 182 ( 1 9 6 5 ) .

22 . N. ^ i u l l e r and R.H. a i r k h a h n , j . Phys , Cham,, Jl* 957 ,

( 1 9 6 7 ) ; J . Phys . Cham., 12^, 583 ( 1 9 6 8 ) .

2 3 . J . C l i f f o r d , T r a n s . Faraday S o c , £ 1 , 1276 ( 1 9 6 5 ) .

24 . C . J . C l eme t t , j , Chem. S o c , A, 2251 (197^1^*"" '^ " ^ \

3.S

2 5 . N. M u l l a r , In "Reac t ion K i n e t i c s in M i c a l l e s " , Amar.

Chain, S o c . Syinp.# Sdi^ad oy S . Cordes , Planum, Naw York,

p . 1, 1953.

26 . T, Nakagawa and H, J i z o m o t o , K o l l o i d - z . 2 . Polyni . , 250

594, ( 1 9 7 2 ) ,

27 . F. Tokiwa and K, T s u j i , J , C o l l o i d I n t e r f a c e S c i , , £ 1 ,

343 , ( 1 9 7 2 ) ,

2 8 . S . J . R e h f e l d , j . C o l l o i d I n t e r f a c e S c i . , 34, 518, (1970) ;

J . Phys . Cham., 2±* 117 ( 1 9 7 0 ) .

2 9 . G.W, tJrady and M. Kaplan , j . Chera, P h y s . , 5 J , 3535 ( 1 9 7 3 ) .

30. G.W, Brady, J . Chem. P h y s . , 58 , 3542 ( 1 9 7 3 ) .

3 1 . M, Yves T r i c o t , D, P u r l o n g , N a i l , S a r s e , H .F . Wolfgang,

Aus t . J , Chem,, 3 7 ( 6 ) , 1147 ( 1 9 8 4 ) .

32 . J . H . f ^ n d l e r . Ace, Chem, R e s . , J ^ , 7 ( 1 9 8 0 ) .

33 . C.W. Brown, D. Cooper, and J . C . S . Moore, j . C o l l o i d

i n t e r f a c e S c i . , ^ l * 584 ( 1 9 7 0 ) .

34. M, wantz , W.H. Smith and A.R. M a r t i n , J . C o l l o i d I n t e r ­

face s c i . , ^ , 36 ( 1 9 6 9 ) .

35 . H. S a i t o and K. s h i n o d a , J . C o l l o i d I n t e r f a c e s c i . , ^ ,

359 ( 1 9 7 1 ) .

36. J . F . Yan and M.d. Pa lmer , J . C o l l o i d I n t e r f a c e S c i , , 3£'

177 ( 1 9 6 9 ) .

37 . J . H . F e n d l e r , 3 . J . P a n d l e r , R .T . Medary and O.A. 21 saoud,

J . Chem. s o c , Faraday T r a n s . I . , 69 , 280 ( 1 9 7 3 ) ; J . Phys .

Cham., J 7 , 14 32 ( 1 9 7 3 ) ,

3n

3 8. K. shincxia and T, Nakagawa, i n " C o l l o i d a l S u r f a c t a n t s * /

i l d i t ad by B , I , Tamamushi and T, I semura .* Academic P r e s s ,

New York, 1963 .

39 . P . a a c h e r , i n " C a t i o n i c S u r f a c t a n t s* E d i t e d by E. J u n g a r -

mann. Marce l Dakkar, New York, 1970,

4 0 . J . C l i n t , J . Cham, s o c . Faraday T r a n s , I . , 2 i ' 1327 (1975^ ,

4 1 . H. Lange and K . H . Beck. K o l l , z . Z. Po lym, , 2 5 1 , 424 (1973)

4 2 . T. Nakagawa and H. Inoua , j . Cham, s o c , J a p a n . , 7^ , 104

(1956 ) ,

4 3 . J . K . C o r k i l l , J . F . Goodman, and J . R , T a t e , T r a n s . Faraday

s o c , 60 , 986 t l 9 6 4 ) .

44 . D.N.Rubingh and T, J o n e s , I n d . Sng. Chara, P r o d . R e s .

Dav. , ^ , 176 ( 1 9 8 2 ) .

4 5 . M.F. Smerson and A. H o l t z e r , J . P h y s . Chem,, 2i,» 3320(1967)

46 . P . Muker jee , j . Pharm. s c i . , 6£ , 1528 ( 1 9 7 1 ) .

4 7 . P . Muker jee , j . Pharm. s c i . , 6£ , 1531 ( I 9 7 l ) .

4 8 . Ch. Durga P r a s a d , H.N. S i n g h , P . s . Goyal and K.

S r i n i v a s a n Rao, j . C o l l o i d I n t e r f a c e S c i , , 155 , 415

( 1 9 9 3 ) ,

4 9 . P,M, Lindarouth and G, L , a a r t r a n d J , P h y s . Chem.,

9 7 , 7769 (199 3 ) .

50 . K.S. B i r d i , i n " M i c e l l i z a t i o n , s o l u b i l i z a t i o n and Micro-

e m u l s i o n s " , E d i t e d by K.L, M i t t a l , V o l . 1, p p , 151-169 ,1977 .

5 1 . P . Ekwal l , L . Mandel l and P . so lyom, j . C o l l o i d I n t e r f a c e

S c i . , _35, 519 ( 1 9 7 1 ) .

52 . R. zana , S . Yiv , C. S t r a z i e l l a , and P . L l a n o s , j .

C o l l o i d I n t e r f a c e S c i . , 80, 208 ( 1 9 8 l ) .

'tn

53 . S. Y l v . , R. Zana , W. u l b r l c h t , and H. Hoffmann, J . C o l l o i d

I n t e r f a c e S c i . . 8 0 . 224 (1981) .

54 . Hercmann, J . P h y s . Chem. , ^ , 1540 ( 1 9 6 4 ) .

55 . M.A. Mazer and G. O l o f s s o n , J . P h y s . Chem., £<6, 4584

( 1 9 8 2 ) .

56. C. Gamboa and L. Sepu lveda , J . C o l l o i d I n t e r f a c e S c i . ,

113 . 566 (1986 ) .

57. L. Sepulveda and C. Gamboa, J . C o l l o i d I n t e r f a c e S c i . ,

118. 87 (1987) .

5 8 . P .H . E l w o r t h y . K o l l o i d - Z . , 20_3_, 67 ( 1 9 6 5 ) .

59. D. Attwood and A.T. F l o r e n c e . " S u r f a c t a n t Sys tems , T h e i r

C h e m i s t r y , Pharmacy and Biology",Chapman and H a l l ,

L o n d o n , ( 1 9 8 3 ) .

60. P .H. E lwor thy and C. McDonald, K o l l o i d - Z , 195, 16 ( 1 9 6 5 ) .

6 1 . D. Attvrood. J . Phys , Chem., 72_. 339 ( 1 9 6 8 ) .

62. H. Hoffmann, H .S . Kie lman. D. P a v l o v i c . G. P l a t z . W.

U l b r i c h t . J . C o l l o i d I n t e r f a c e S c i . , ' 8 0 , 237 (1981 ) .

63 . P . 3. N i l s o n . H. Vfennerstorm, and B. Lindman, J . P h y s .

Chem.. 8 7 , 1377 ( 1 9 8 3 ) .

64. R.H. o t t e w i l l , c,C. s t o r e r , and T. w a l k e r . T r a n s . Faraday

S o c . , ^ . 2796 ( 1 9 6 7 ) .

65 . J . Lang, A. D javankh t , and R. Zana , J . Phys . Chem., 8 4 ,

1541 (1980 ) .

66. M. Almgren and S h a n t i Swarup, j . P h y s . Chem.^£2 ' ^"^^

( 1 9 8 3 ) .

67. P . L i a n o s and R. Zana , J . P h y s . Chem., 8_4, 3339 ( 1 9 8 0 ) .

41

6 8, S. Ozeki and S. I k e d a , J . C o l l o i d I n t e r f a c e s c i , , 77,

219 ( 1 9 8 0 ) .

6 9 . H. Hoffman, G. P l a t z and W. U l b r i c h t , J , P h y s . Cham,,

_85, 1418 ( 1 9 8 1 ) .

70 . T. Imaa, A. Aba and S . I k a d a , J . P h y s , Cham,, 92# 154 8

(19 8 8 ) .

7 1 . K.G. Gotz and K. Hackroann, j . C o l l o i d I n t e r f a c e S c i . ,

1 2 , 206 ( 1 9 5 8 ) .

72 . S . Hayashi and S . I k a d a , J . P h y s . Chetii.i 84, 744 (1980 ) .

7 3 . S. I k e d a , S . Ozaki and i'*. Tsunoda, J . C o l l o i d I n t e r face

s c i . , 22, 27 (19 80) .

74. G. Lindolom, B. Lindxnan and L , M a n d e l l , J . C o l l o i d

I n t e r f a c e 3 c i . ; , 4 2 ' ^00 (19 7 3 ) .

75 . R. Dorshow, J . B r i g g s , C.A. Bunton and D, ^ i c o l i , j .

Chem. P h y s . , 86, 2388 (19 8 2 ) .

76 . C.Y. Young, P . J . M i s s e l and G. tenedeck, J . Phys . Chem.,

^ , 1375 ( 1 9 7 8 ) .

77 . C.A. Bunton i n ••Reaction K i n e t i c s i n M i c e l l e s " , Ed i t ed

by E.H. Cordes , Plenum, New York, 1973 ,

78 . E.H. Cordes and R .B . Dunlap , Accounts Chem, R e s , , 2

329 ( 1 9 6 9 ) .

79 . G.J . U i s t , C.A. J u n t o n , L. Rob inson , L. S e p u l v e d a , and

M. Statn, J , Amer. Cheni. S o c . , 92# 4072 ( 1 9 7 0 ) .

80. w.L, Hinze and D.W. Armst rong , iSds, "Ordered Media i n

Chemical S e p a r a t i o n s " , APiarican Chemical S o c i e t y ,

Washington, 1987.

o

8 1 . P«G. DeGennes^nd C. T o u p i n , J . P h y s . Chem.^ 86 , 2294

( 1 9 8 2 ) .

8 2 . M, Almgren and J . E . L o f r o t h , J . C o l l o i d I n t e r f a c e S c l . j

81 J 486 ( 1 9 8 1 ) ; M. Almgren and S. swarup , J . C o l l o i d

I n t e r f a c e S c i . . ^ ! » 256 ( 1 9 8 3 ) .

8 3 . D . J . M i t c h e l l and B.W. Ninham, J . Chem. Soc . , Faraday

T r a n s . ; 2 , 2Z • ^^^ ( 1 9 8 1 ) .

8 4 . K.R. vtormuth and E.w. Kale^ J . P h y s . Chem. ,91 6 1 1 ( 1 9 8 7 ) .

8 5 . J . Fang and R.L. V e n a b l e , J . C o l l o i d I n t e r f a c e S c i . » 1 1 6

269 ( 1 9 8 7 ) .

8 6 . H. N. S i n g h , C D . Prasad and S. vumar, J . Am. O i l

C h e m i s t s S o c 2 2 * ^^ ( 1 9 9 3 ) . 8 7 . A. K h a t o r y , F. K e r n , F. Lequeux* J . A p p e l l , G. P o r t e ,

N. M o r i e , A. O t t and W. Urbach , L a n g m u i r . r ^ , 933 ( 1 9 9 3 ) .

8 8 . A. K h a t o r y , F. Lequeux , F. Kern and S . J . Candau,

Langmuir . , 2 • ^^56 ( 1 9 9 3 ) .

8 9 . P.M. L in temuth and G.L. B e r t r a n d , J . P h y s . Chem. , 22.

7769 ( 1 9 9 3 ) .

9 0 . Z.K. Zhou, P . Q . Wu and C. X i a o , Acta P h y s . Chim. S i n . ,

_4 . 340 ( 1 9 8 5 ) .

9 1 . V. R a j a g o p a l a n , P . S . G o y a l , B. S. v a l a u l i k a r and B. A.

Darannacharya , P h y s i c a B*, 180 , 525 ( 1 9 9 2 ) .

9 2 . H.N. S ingh and S. Sv/arup, B u l l . Chem. s o c . J p n . , ^ ,

1534 ( 1 9 7 8 ) .

9 3 . 0 . B a y e r , H. Hoffmann and W. U l b r i c h t , "Proc . I n t .

Symp. S u r f a c t a n t i n s o l u t i o n " . E d i t e d by K.L. M i t t a l

and P. B o t h o r e l , v o l . 4 , Plenum P r e s s , New York, 1 9 8 6 .