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: [email protected]
~~:~-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
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 ~
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
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
.:...~
<...,~
..-
(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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