SURFACTANT/POLYMER INTERACTIONS WITH SOLIDS: applications inflocculation/dispersion, flotation, coatings, nanocomposites and biomaterials

Prof. P. SomasundaranNSF Industry/University Cooperative Research Center

for Advanced Studies in Novel SurfactantsLangmuir Center for Colloids and InterfacesColumbia University, New York, NY 10027

Outline

* Importance of conformation/orientation of surfactants, polymers and their mixtures

* Techniques used to monitor adsorption/conformation and flocculation/dispersion

* Confonnation of surfactant adsorbed layer

* Role of structures in surfactant adsorption

* Polymer adsorption/confonnation

* Flocculation with dispersants at ~ dosage and double flocculants

* Hydrophobically modified polymers

* Deposition under difficult conditions

* Nanocomposites and biomaterials

Reprinted from "Conference in Mineral Processin& Lul~ Swede~ 2000~ pll-38

11

18

~x~ended Abstract

Introduction

Polymers, surfactants and their mixtures are widely used in many important industrial

processes such as dispersion/flocculation, selective flocculation, flotation, rheological control,

deposition/coating, detergency, oil recovery and materials processing in general. In these processes,

interfacial behavior of particulates is determined by the adsorption of polymers/surfactants and,

equally importantly. by the nature of micro- and nano-structures of the adsorbed layers. Monitoring

and controlling of the adsorption, particularly conformation, orientation and association of adsorbed

species, can improve the efficiency of these processes and enable design of new processing schemes

and reagents.

Our efforts to explore and control the adsorbed layer depend on a multi-pronged approach

involving the use of fluorescence, ESR, NMR, cr Scan, SPR, QCM and AFM techniques, along,

with conventional techniques to measure flocculation, surface potential and hydrophobicity. Results

'.obtained using these techniques will be discussed along with possible new applications.

Surfactant Adsomtion

Adsorption can be considered as selective partitioning of the reagents into the interfacial

region, resulting from the more energetically favorable interactions between the adsorbate and the

solid than those between the former and the species in the bulk solution. Interactions leading to

adsorption include chemical bonding, electrostatic interaction, desolvation of the surfactant polar

group and the mineral surface species, hydrogen bonding, van de Waals interactions, etc. By

changing the nature of solid surface, solution conditions or structure of the surfactants/polymers,

12

adsorption as well as confoffilation of the adsorbed layer can be controlled. Manipulation of the

adSorbed layers for desired perfonnance will be discussed in this talk.

In surfactant systems, in addition to solid-surfactant interactions, surfactant has the tendency

to Conn two dimensional aggregates called solloids ~urface colloids) or hemi-micelles due to the

association of surfactant hydrophobic chains. This self association not only increases the adsorption,

but also changes the conformation of the adsorption layer and consequently the interfacial processes

involved.

The adsorbed layer can be affected by the structural modification of the surfactants such as

chain length variation, branching, aryl, alkyl and ethoxyl additions. Even the position of the

functional groups on the aromatic ring of a xylene sulfonate was found to measurably affect their

adsorption. Changes in the nature of the functional group also affect the adsorption; for example,

sugar-based nonionic ~urfactants show unexpected selective adsorption behavior, opposite to that

shown bynonionic ethoxylated surfactants. These surfactants are particularly attractive since they

are environmentally benign. Another way to change adsorption/conformation is by adding a second

surfactant. The synergistic or competitive effects between two surfactants can drastically affect the

Since mixtures of surfactants are wildly used commercially, the behavior ofadsorption process

mixtures on the adsorption/conformation have practical implications.

Pol~er Adsomtion

Polymers are also used in mineral and material processing and their conformation can be

manipulated by changing solutions conditions such as pH, addition of a second polymer or

surfactan4 by polymer hydrophobization or even by the order of addition. Such manipulation can

lead to flocculation or dispersion even at the SAME adsorption density. Even the so called low

13

molecular weight dispersants can act as good tlocculants under appropriate dosage conditions

Hydrophobic modification of polymers have the powerful ability to impart controllable

surface activity to polymers. Such combination of polymers and surfactants may yield useful

properties not exhibited by either individual component. For example. these polymers can be used

to obtain flocculation or dispersion in aqueous or non-aqueous systems of hydrophobic or

hydrophilic solids!

There are many approaches to control the polymer conformation. For example, pH shift of

a suspension can change coiling of the adsorbed polymer to yield better flocculation or dispersion.

DeRQsition and NanocomRQsite

It was recently observed that deposition of particles can be achieved even under unfavorable

conditions by incorporating appropriate tethers (hairs)on the particles. We propose such deposition

to be due to reconfonnation of the hairs on the particle with the complimentary groups reaching out

to tether and the antagonistic ones retracting. AFM experiments show that the zwitterionic particles

of net negative charge to exhibit attraction as they are brought close to a negative glass surface while

anionic particles of the ~ negative potential experience only repulsion

Control of the adsorption and conformation of polymers and their mixtures have important

future applications in many processes. Thus a layer-by-layer deposition process has been developed

to prepare core-shell nanocomposite particles using controlled polymer adsorption. Ceramics

constituted by such nanosize granules show enhanced properties in various applications. Submicron

size alumina particles chosen as starting core particles are first dispersed in this process by pH

control and then modified by adsorption of anionic polyacrylic acid to faci1itate subsequent

deposition of nanoparticles on them. A key step in the processing involved removal of excess

14

polymer in the supernatant after the adsorption by controlled washing so that the added nanoparticles

do not self flocculate among themselves. Coating of nanosize particles was indicated by the charge

reversal of the micronsize composite particles. The isoelectric point of the composite particle was

found to be close to that of nanosize particles under both low and high coverage conditions.

Scanning electron microscopic observ'ation of coated particles showed full monolayer coverage of

nanoparticles on core particles conflnIling the efficiency of the coating scheme discussed here. The

compacts prepared using this technique exhibited improved flexibility and green density. This work

revealed the feasibility of coating nanoparticles onto micronsize core particles using controlled

polymer bridging for preparation of multilayer nanocomposite powders.

Other applications will be illustrated with examples from the biomaterials area.

15

~

J.~ K.Si-'--A SiYaklnnar M CelikP. c.~ I> UuJ Claudonc C M8n.dC Malt~ S. EI-MoftyI. Xi.YI r (1arkcnQ X" J KlCfcrB. MoudIiI X VuI. Ricf V R..T. W- L H.-IA.~ AF..KDas OK-M Kosch8k 115.1'-1:.11 Mol , K V.,I,-.,vA. l1O)01J LJ.R N..-JK.V Vi$~ W Ati8PC E Robcns S Ac.Q At..-1Ok B. l-'ilClJ 8 AIkIcncn M DaaitzR VartJ8ICJ\. S T~S Vidoinallc " 01.;

o.~L.T.LaE. SnellK. Tj~.-.H. EI-s.ftDM~ovicM Ytia..jiR.,S. Kri"-'-P.Si~LZJI8IcJ. Zhe8aVR.P-nanA.AJli'" 0 lluaigG.C SfUlYAF tlol'-MlefY 8 thJ8t¥R.~likS~S PhinopsL McAnilfer

K.P.~CUK-WqTV~E. FaRMiddIclOn'-Marc-R. K*kriS. SI.otri

A-c T.CMn

CRmerK. V Via..~"EL Smllh. JrYC L";-.Wq)R~AAIh

OEKIIZIIpxienIiRR~lNiII*ov

P.J DI)dSOII

C'oll.b..raton:Pror. rlaTO !'rur 01)1" I...,.r Ham~ I>' B Pctbica~ " Prof I "MM)\ !'r.,r () I. W-c I>r ~iPro( II caa- I'ro( J M c-.. I~ S (; Mall!- ~ K M s..-Nllin@()r V (>SUlLo. l'nlf KIll",,!! !'r..r I> ". I'UCfSICnau I>r GI-: AprDr K J. Mytd. Prul II ""'~aL l'rof R .. JI. IX (j Y ~.Prof 1 J ... (k I:.() (k~ 110 I' ('a,.e I>r R R--.I), S ~h l'ro(' W II.:,,'~ l'r..f K N~lIr889an I'ruI' J.K Ban...

IUCS NSF Industr)'/University Cooperati,'c ResearchCenter for Ad,'anced Studies in Novcl Surfactants

J.tesearch Areas:. Surfactal;1ts and PolYTT}ers for Colloidal Procc,sse~

(Dlspcrsaon/FloccuIation). :. ",OJ' );.i~ :. Environmentally Benign Su:factants. .. ';-. :: .

. Sllrface Active Agents' Intel action with ~i~~b~sal1d Biosurfaces.

. n)aracterization of Novel S~lrfaceAct!ve Reagents and AdsorbedLayers: Advanced SpectroSl opy for mIcro- ,-ana nano-adsorbed layers.

. Surfacti;nt 8;i1d Polymer Aid.:d f;lectrode~~~Or1;i~Corrosion Control,Cf)'stallIzatlon and Polymer zation. .:: - .:~

Faculty: , " .i'T~'-::.!."~ P. Duby, C.C.Gryte, B..Pe~ca, p.~masund~-,~.;:J...T~, A W~

Sponsors: . ';:,-: ,!'

AKZO Nobel, ARCO, Collate-Palmolive, Dispersion Tech.,, 'c...

Florida Inst. of Phosphate ~~h. HaIlibuiion.,: Henkel, Hercules, ISP:\1itsubishi Chemical, PQ Corp., Shipley Roi1a~ Rhodia, Unitevcr,Department of Energ)'

Contact: P. Somasundaran(Director)/Maizie FletcherPI lone: (212) 8.'\4-2926. Fax.: (212) 854-8362, E-mail: ps24@cotumbia.edu

~~:~-t-.o,/J CENTER OBJEcrIVES

-. [Iucldate mechaaisms of iaterfacial effects u a fuaction of

STRUCTURE of surf.cr.aa aad poiymen for varioa

solids and media. - SCnlCt1lre-p~per1y relaCioas~lps.

. Modify surf.ce .ctive .ceaa with fuactioaal groups co

eahaacc .ad coab'OJ beb.vior.

. IltsilD more errlCieac .leDts for optimum perform.nCt.

. 11~..iK proccsaiag scbemcs for dnlred prodUCI propcr1ies.

. InvesticaCe and develop eDviroDmeacally ~ surf.ccaats.

- BeICer ~merdal products .ad pfWe8aC8.

-17I

~!;l;J:

19

Which polymer conformation is better for aggregation.dispersion, adhesion and deposition?

STaETOfED.. DANGU~5n.ETCHr-J>. F1.AT

Tht p~rrorm.nt~ of. potyal~r d~p~nds 001 only upon lis 8dsorpllon d~.sil!bul al"1 "" il5 conformation .nd orl~nlMlion .llhe inl~rf.ce.

Prllbl4:m:

Lack or l!:!l!! teehniquu to detenuine. thc conformation and orientation at solid/liquid interface.. cllanges in them. dynamics involved

20

MeU1od

Probing conformational behavior ofpolymers using pyrene labeled Polymers

p --> p' (m~p. + p -- pp"(-*-1

Pyt8ne Exclmer forft\ation

._.i'= .p'

..i""~.._1.-Polymer .nlchedLow Coiling Index (Ie/lm) 1)"'" - If

.Ire'lda Ie . raItI..-"'-""" Co&-

'~~\

r-.-8.-.

-.

, -. -- of --=.. =="'-= -~.;; CAT - -.. - ~ -.. - - of.- - ..R.accaaA~TDft.

t. --~.==*".-.;oc.--~ .--~~-* " ""-'--_12

-",-,,*--~CAT- w.- ~ ... - -. -- ~ CAT - .. .

--~-.. --~--_~CAT_.e.y

~ tho CAT ---- --~ - -~ ,...~--~_."-'--~CAT-. U81"",_~""

~...--~--, ---e.y-

- ..- -, -. ,..,--.'.-. - .-- 01- ~"--~

l...1.. ,- -f.--I, , R~~A.~..J,..- , 1..:1,... -fl-j.--f

~L-I:.-:IT (1"'",1: -I.l-c:r_- t:rAT)l.RR.AN~",/VI4R. .'." ( / --~._-~---c ~

"

;f :,13

1.2~""

\05()KPTK)N Of DOOECYLSULfATf: ON ALUMINA

_::1:"""""". -. - - - .r- -

I ... Af.tNINA II 0:IM*;1:_'6-" I lIV

w-~---~~...'

I".

.,I~IO

~I

J'.'0:

Exo:inlCf 10 -- ,.1;" (I II ) or dinaphdtyt P'OP8IIe (ONPIt m

.. SOS..um... slunies as . La"- ors~ 8d-.p(ion density (0.1 M N.c1. pH 6.$) ~ Surfacta~ aggregation nuni>crs detcmBnod

at various admrjltion densities

U}

111, '16~ II

12112321

.!"!:{~~--~II.: "AL~0.1 M NaC1, ..16.

IOOcP

.~..

... ',IV 1,111

00.-)1 -.IC8/C ld8WIICion. ftIIcoi

r,r-=8i E." ~ oClX)XYl. ~ AcId

0

M..-IIc Ycld

1\~

\li

:~.w!~;:oJ

j~~0;:.~

~rAll,

,-"N: En.~,..)

~ 160..W¥Cf -140.H),*,-=.n-~

R I\'~.n rink" I«.IY~--~

6~ \ III .11

24

--lalO" I.:

~M

CMC

"

(as ...

~ of-- "'(---"'-"UPOC' 10 1286_-1 ->as . r-.JIDII of 0 ~ ""y

~.l::-:~~~~. . .-;~~

,,-.,L-;;,~~~-,-1

G.)

~

I!!----'

'KIU... -,

I~IO lalO

Rcsjdu8I DDdoc)~lf8Ic. M

--

SURJi'ACT~ S'nmlm;

«:11 XY1MF. aJUONA TD

:~~~~6lj'-':' \ CRj

~-C113

CH:~~::~-30 CH]

80)-

META

PARA-I

~::-;; CH3 -¥ '-nJ PARA - 2

80]-

POLYEmoXYLATED NONYL PHt:NOlSn - 10, Is. 20, ~

~I~ Uf' XYLr.N1 aJUOHATD ON ~~~ a-.. 18., ., ~~~,.. ~ "M

hl'- I 'ic

r:t~.1.1t~

III.'"

oillal'

I''aleu . . .

la"" h.'" 'al'" 10"".~IA-!. ~U aN;..~

.. ~~~~:. ~ ,,~'C~ =, !,~I:...:'~..i:."7H;i£"AJ1 c~. o. mLIA.

1. a.nc w Ie ~w-. ~ ~---;alc.r- (~ .... ..,-" A r~ .r "'.Ie (u"

~ .. "'" c"" ;. META3. H..- ~ -.. .r - PARA ... -

MtTA ~- .r ~01.M7 .. "Ii~ ...,.1'"G4118

.. ~..", .r.. .- PARAXYLEr-"E ia r,So .r .. ~ - u ""-' .0 tNt.r

"".'0 I". [C'...,

r:~:.:. '~':"'~:...(q.;~,., .i:-~:;-.. ':,~.'

INTRODUC'nON_0 OJ-=::---= I ~ I

Chemic.1 Scructurc~.lnd Molecuiar Models orTypical Suc.r-b"sed Sun.daRts (I)

""",) 1.p-I>-Ih..-""j.J.: ft-dodccyl-P-o

. -~$~i""""""~~.

r-"'~"".~ ..'... -- ., ..d ~. .. .. .-.By -r-. ~ ~

~ M&c8 .. 88f8c8J ~ c«ecd¥eIJ.

If8ft ~ ~ b ~~..:.,~

06r Fod , ~ 8d ~ ~ 10 ... , ., -1

E8IIJ~.;:.I;.

P-al~~-~

DilPcrsion. e-IIi.-L

M8InI~

0 - c-* ~

H~bkity or AI Partida .Aft... .-De.sec)1-~D-Malto.ide AdIOrptio.

,I""" ' -

. ~... r-

~i~. -

1..

~:';.I.

~.

lair'

-.'- .i.dr

L.i/' .~~~

,., .-.. .. .-m( ~ ,0

"I1Ie A-. ~ kr*~i ... c-..,.. .. .&c.-IWIe8III8 81 ~ ~ ...

,~-\;.. ...,

I-~-= -~ ~.~P~PO~d confo~=::n Mod-el for the "'

Ad~orp'llIn or n-Dodecyl-J}-D-Maltoside on I

Ilytlr"phili~ and Hydrophobic Surfaces in Aqueous Media Wby Surfactant Mixtures?

'Ll .JlImportaace of mixed surf.mat system:

SUrrl.llnls .s.d .nmm.r.illly or. in.ariably .i.lur.,~.H or... Ko"o..i.. u _II as ~n.n.lal.rr..:ts ormi...,.. ever i.divid.al..rfa

~~lrlll\! ~ ~ 11._1~~

New techaiques luch as ultrafiltration.re available for directly measuringmonomer conccntrationsin mixed lurfactant systems:

('urrent mudel~ fur mixed Surfactant!lrstems are not suitable to predi~t thebchavior ofsurf.~tant miltum

Ilydr~rllilil: ~id--

,:r.-:;,';111:'~~

,

=-~~-~.~

[--~";;"-;'-"Y,- '~'I.-

.At-C. "

..,;..,.,J('-,L u..r.." , "aI , II ,. '. _"'ff"'" ~~~ --to:--

., tlf.r"'",""o;.nll) 1"~Ich.-c_al-~.XI'I' _m", "OIK~"".,it.., """'"".'11) ~_.

1.."".1., ",Iu'it.. ,tI , nut ", ,,10: r""h.'~~' ~*'=

.;;cbem.tic model for bia8ry Jurf8et8at system

II

III

I 27

.~~~~ t

.':-:;';:; :... - ~_.. - -.L. . c

~~-~'*"~--~r C d

pH-C pH-' pH-IO

."""--'~e.~y:~,>, ~~~::t(

~ntCl or pH on P AA conrormaUon Ind nocculat;"n'"p"ases or alumina suspeallon with PAA

.. .It 1Ie

, .I

~ .@

f; 10 5 !

:60 of- .-.:50 - ~

E '..3 M

=.. .!.. =... JO '. %,J

%0 ~Ij I18 ..

J 6 " , .0 ..pH

. Florrulation or alumina susp~nslon it s;gnin-:antly

~nhanr~d In bAth t~rms or,up~rnat.ntrl.rltr :lnds~lIli.C r.t~.

Current Work(supplementary study on polymer conformation)

PM confonnational change and flocculationresponse as a function of Perco) concentration

!;~.~ I i:IocaII8IiCWII.JIlpCnion I~:~i£~

Dual Polymer systems used for flocculation. #

a& .., . .. ...',. ---.'-. a. - .\. .. ..~~b-'6:a~

too

_-AA-

~ .,.:. to ~~8"\, ~t.~ .

-----

0.1 1 10 100Concentration of Percol757, ppm

The pre-ad&orbed anchor polymer ,el8 .nl~hed withIncreasing the second 'arver polymer.

MaKlmum l1occulatlon at Intermedl.te .ntcfllng!1..

--

30

~

Dual Polymer Flocculation Di$persion 01 Micro.floc,

Effect of Soli.ds Loading on Conformation of PAAAdsorbed on AKP-50 Alumina

~L pH04, PM -to py~M MW.7~k. PY~M;PM03:'7. Tomp.02S-C. 0.03 M N.No,j

1 1

c Ne0 0- .75.- C)

ee- -0

0.5 ~

.)[ 0.8-1'-- -- -Q) . 'C

..5 E 0.6

CI~.5 - 0.4

'0<J 0.2

-...40- ~

.~cQ)

'0

0.250300 10 20

Solids loading, vol. %

. PM molecules become more extended as solids IOllding

Increases.

Effects of Solids Loading on Conformation ofPEa Adsorbed on Geltech Silica

Aggregation of Hydropboblcally Modified

and Comb - Like Polymers

.,E.E

iI.i,!

,\c. MoJlCSh, QU8 Xu, K. ~iya4"'A and P. SomasuAdaraa

La8cmllir c...ict" ror cea",.. and laterfacdCDI..~ia Uw..nity. New York.

--. . ... - - - i".

-H-

. mect or Hydrop"bk ModifICation or Water-Soluble Polymers on tbelr Sollilinn Deba.lor

. A&&Feialion bcba.ioc or Comb-like Poly_..

. Intu~ or !he Modined Pulymm wIthSurfada.ts ad 1 8Aics

. 0.3

- 0.21

. 0.2 ". .i

.1.15 .

i""~

'0.01

. , , """,";C."O-{,;,v

. 10. 20 . 30 40 SO eoSoIIdsi,.oadlng, voJ% ".

. PEO .Iso bKoma stretched wldllncreuiDC solidslosdinc... 8otk nndillp suCCestth.t ~IYlllen .dopt. m.ore sp8ce-say~ ~D~rm.tloD duetelDCreased particle crowdlac. .;. ." ",'-

I"~ 'j31

"1

...

...

..7

[...

...

0.4

I.a -

U.

1.1

:CUlation/Ulspersion

-.---0- --

~;..";-£i:'..~ !!vdrouhobicaUv ModifiedCouolymMj

WHY?

. I'olymers and surfactants are widely used inindu~trilll pro~esses as, for exllmple, stabj.Jizers,nllcculllnl~ IInd rheological modifiers. :'

. 11~'drorhol>ic modification may b~ u~ed to impartciJlltriJllf1ble surfOicc activity to polymcrs.

. Combinations of polymers and surfactants may yieldus\'ful propcrties nut exhibited by eithcr individual

component. .

--

C:ylilldrital Vww or A OCfJI-PMA VE MDIoc8IeHELICAL STRUCTURE 0' OCIJl-fMA VE MOLECULES

lllIial_n '..18,. . Iowv l d8nI-rv .. . ,-.It of _r..-11 odJ_I

\.t!{~..

R = CHJ => Poly(malcic anhydride nlethyl vinyl ether), PMAM;VE

R- Ca".7 => Poly (maleic anhydride octyl vinyl ether), PMAQ\'E

... .~~O.9

Jo.a., 0.7

~. 0.6I

""~

0,5' .. . I0 I 1O 100 tcm

.. .DAPRAi. c-.:-.Iioa. ~

118 .., 18f.u~ ~ as ~ itDAPRAL _1Ift- ~.. ~r ~,-'" ~ to ~ iM8rKtin

1J. ~ -- 8IDt 88m 8t . mlEh bNef~lIII8tm aI d1C lku11N ~C.: dIIn iI die~in

~ aIOditI8d POi1D*. DAPRAL. _billa, bdh~~ ~~.."-~~

H).I.ili~ SIde a.n.

H).Ir1IpIIoI8~SdcC

Hydrllphilil: Side Chains

Hydrophobic Side Chains

-I: - . . Ol1tt...Ie'i"l~ilml

I - - 00 .0 0 0 ., .. 0

.(-,-, ~ - 00- 0

o. .\, .

AlumlD8

"PII1lclt

Hip DAPRALC-~Electn»Utic 8IId StericStabiJiDd-

~ DAPRAL Coocentnd. IH.J'Uropilobic F!occuJadon .froEleclnlll8dc Sl8biliadon

Influencc of DAPRAL on the Stability of Alumina Suspension

EFFECT OF DAPRAL cmz ON THEDISPERSION OP CRAPHm POWDER IN

AQUEOUS SYStW ~

200 400- ~ 100Initial DAPRAL c-..

ICMMI

DAPML QIKJ D~ of Qalilie. Lke dieAnmc/Nu.o.c s..fK- MiKIIn

33I

tiT;:;\,~

I ;35 "~i~,~~~

A Novel Scheme for ParticleDepositionlDetachment under

Unfavorable Col1ditions; Role ofReconfolomation of Tethers

Use strategies learned from nature todevelop particles capable of

facilitating/preventing deposition as desired.

MotivationIt ""'!i ub!ic",'cd (hut

'. - -::=_~ Depusition 011

§.~~ Tooth Surface.' ' ,I" '; "11:.,,,

+., .~Ireptococcus Ac:tinO;mycessangui~ n~l!Slundli . ,n1p' , ,.

..,110,"-1111 "'r,'ril1l..nl~ r..,..:alcd i'"I)urt.n" urb.in. (fimbria&:) .,.

.1,'/i/",//"lC"'.~ ..I,,"/\"/f.\" rpurl:nl ulld /J//fIClnt strail'.\/

r---~.~ ~~- .~

~,;, I..;~- t.", ,---1~ ($)

~";J I ~.9l!!yd~~patitel - - ~

(;;) - ..Ra8lion/dC1""iliun S - no I..Icncliun

-~

Q

I'rl'rllr~(i,)n Itrlll.'l'llure for Multiluycr NunocompositePartil'lcsAFM Measurements of Particle-Surface

Interaction. Q. -~.,.!

Rcpul5iclnz I.. ,.-

i.. ""-E I

l,,~

\.;-w , ",;1.,..

Z..""'" I ", Altrl8ctiun'-

- - -- -- ,;; :;-;;;-F CI.n~ [: Ckn -

0.

-I ' ---.. ~. .. .., . ,..., ."., ,...

. Nole thllt anionic IlItl:x pllrticles (of the same Det negative zeta

putl:DIIaI) I:~pcriencc unly repuisiun, \vhereus tbe z,,'itterionic

1..It:x particlt:c'I t:xpericl1cc ;an IIttrllction.

~ '" _.a:,

,.""",!. .I"",i". C".I,'" \1,1'- ~Iiu"r" uf ~nnultk .Iumina1:- ,"""p"';lr p:lrll""" "pd ,\"1'-1:- partict",-"illlp"I""",r, -p"I,uIY'h"r

. \fl"r 110" "";llip~ pr',(".'. ""PI,...,il"I",rl;cltS ,,'ilh grainy surratt r~al"rC wtr~ obs~rvtd.

. 'li'I"~ "rcorr nnd 511~1I I,nrlio:l," .b"w 00 .illn urip'~rnctions b~t"o~" !hom.

llumogeneity IIr ;\Kr-15/~linotek Hemlititl:(Ii) NII"ocompflsites and (b) Mixtures.l\1unitored "sing EDS l\1easurements

.,.L'0.. ." -, . . .

.,' "-. _:. -- ---:

lffl'ct of ('lIlnp"l'~~illll I'rl'!;~u"l' 1111 (;rl'~11

Ocnsity IIf (:11111 positc (:olllll:ICt..,.. '.

/--;. .. .'

PAA -: 150000

pttC.'-OJ3MNH,NO,Solids lNding: 11 VG~

Nqlt~ah $o~l.oad",q.Na~. AKP.15. AKP.Is" ~ M4o1u..

~

It

.

tic

;t;..c

~...~~0

.!I-C.

t!.

Go

.:...~

<...,~

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(a).N8noco~posife- - - -~ .

so0 20 CO 60 80 IOii 120

Compression P,.ssure. MPa

. III fulltr:I~1 tfll:(lm"lm('lIt~ limlivjllll:11 or:lli,,'(II.II:lIIUCjJl\I"tl!iiIC~ ~'iI:I(1 :llilll::l1

','I;,ti"II~hi" urgrl'1:1I IIl'lIsit~.. \\'ith I:tml"rl'~"iol\

i.r"!i~tlr,', 'Ini" "Uggl'!it" 11l'\ihilit~ (Iflhl:

,.:tl,u('..mp",il" ,Iru,'.ur.:",

. Thc n1l1101:(lm r",;ite disks result in

tletter com rol1cl1t distribution.

Potcllti~\1 ,\pplil:ations of theI:untrollcd polymer adsorption proccss

:'l'II1!,,'.,ml'IlSill: 1:."'lill~""11. lI,illll""",p..'ill"'

~~~~~VIJ,.IJIY"""IJ.",r:'IJ"C5C\.If1f1l:omp",irl: IiIm

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37

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