CA3018359A1

CA3018359A1 - Viscosity modifier in enhanced oil recovery-method of producing same andused therof

Info

Publication number: CA3018359A1
Application number: CA3018359A
Authority: CA
Original assignee: Tam Michael Kc
Current assignee: Tam Michael Kc
Priority date: 2018-09-24
Filing date: 2018-09-24
Publication date: 2020-03-24
Also published as: CN110938180B; CN110938180A

Description

Viscosity Modifier in Enhanced Oil Recovery- method of producing same and used thereof Zhen Zhangl, Kam Chiu Tam', Qun Lei2, Jianhui Luo2, Baoliang Peng2, Pingmei Wang2, Lipeng He2, Xiaocong Wang 2' Peiwen Xiao2 Department of Chemical Engineering, University of Waterloo, 200 University Ave W, Waterloo, Ontario, Canada N2L 3G1 2Research Institute of Petroleum Exploration and Development (RIPED) PetroChina 20 Xueyuan Road, Beijing, P. R. China Postal Code: 100083 ABSTRACT
The present disclosure relates to the synthesis of BAB structure poly(methyl methacrylate)-b-poly(ethylene oxide)-b-poly(methyl methacrylate) (PMMA-b-PEO-b-PMMA) with designed molecular weight of PMMA and PEO blocks via the Activator Re-Generated by Electron Transfer (ARGET) Atom transfer radical polymerization (ATRP) and their application as viscosity modifier.
The ARGET ATRP was performed with ppm level amount CuBr2 as catalyst and ascorbic acid as the reducing agent to overcome the sensitivity to oxygen of traditional ATRP.
The association properties of PMMA-b-PEO-b-PMMA were comprehensively studied, including hydrodynamic diameter, surface tension, morphology, storage (G') and loss (G") shear moduli, and viscosity. The synthesis and association properties of PMMA-b-PEO-b-PMMA provide a design strategy and the application of BAB triblock copolymer for polymer flooding in the field of enhanced oil recovery.
The aqueous solution of PMMA-b-PEO-b-PMMA was prepared via solvent-exchange method to induce the association of PMMA-b-PEO-b-PMMA in water. The PMMA-b-PEO-b-PMMA
significantly reduced the surface tension of aqueous solution at low concentration. When the molecular weight ratio of PEO block to PMMA block was about 5 at the same PEO
chain length, the PMMA-b-PEO-b-PMMA aqueous solution possessed the highest viscosity and optimal theological properties. The PMMA-b-PEO-b-PMMA could be used as a viscosity modifier for many applications, such as polymer flooding in enhanced oil recovery.
FIELD OF THE DISCLOSURE
Disclosed herein is a synthesis method of polymeric viscosity modifier consisting of a triblock copolymer, PMMA-b-PEO-b-PMMA suitable for polymer flooding in enhanced oil recovery.
BACKGROUND OF THE DISCLOSURE
The viscosity control with varying conditions is critical for a variety of applications, such as paints, cosmetics, food, and chemically enhanced oil recovery (E0R).1-2 In EOR, polymer aqueous solution is injected to reservoirs as rheology modifier to achieve the viscosity of the underground oil, and this method is called polymer flooding.34 During polymer flooding, the water permeability is reduced due to the increased viscosity, leading to a reduction in the water mobility. The polymers used for polymer flooding should satisfy several requirements, such as low cost, high injectivity, resistant to mechanical and microbial degradation, high thermal stability, and high tolerance at various pH and salts content present in the oilfield)' 5 Polyacrylamide (PAM) and partially hydrolyzed polyacrylamide (HPAM) are the most commonly used synthetic polymers in EOR due to their low cost, tolerance to bacteria and mechanical forces in the underground of the reservoir.6 However, the PAM and HPAM are highly sensitivity to brine and surfactants, which makes them ineffective in reservoirs with high salinity conditions that severely limit their application ranges.
Many biological polysaccharides and their derivatives, such as xanthan and hydroxyl ethyl cellulose, are commonly used biopolymers for polymer flooding in EOR due to their excellent compatibility with salts and surfactants." However, the polysaccharide is vulnerable to bacterial degradation.' The selection of polymeric systems for polymer flooding significantly depends on the conditions of the oil reservoirs. Each polymer flooding system is unique due to the complicated conditions of the reservoir, such as permeability, viscosity, temperature and bacteria.' 8 The polymer structure and molecular weight should be carefully designed and controlled in order to meet the specific requirement of oil reservoir."

2 Associative polymers (APs) are another type of commercial polymers being employed as rheology modifiers in EOR for many years.6' 12-13 APs contain segments that have a tendency to associate in selective solvents.13 The associative segments of the same or different polymers interact with each other and thereby generate additional viscosity by forming a transient polymer network."-15 Compared to standard HPAM, associative polymers offers several application improvements, such as significantly lower polymer consumption, excellent mobility control, and improved sweep efficiency. APs are amphiphilic due to the presence of both hydrophilic and hydrophobic segments, which assemble to form micelles or aggregates, similar to that of surfactant."'" The hydrophobic segment is soluble in water and associates to form the inner core in aqueous solution, while the hydrophilic segment forms the corona, leading to a core-shell structure. APs with BAB structure triblock copolymers have attracted much attention due to its unique structure and associative properties, where A is the hydrophilic block and B is the hydrophobic blocle648. When the two ends of BAB triblock copolymers aggregates into a core-shell micellar structure in dilute aqueous solution with the looping A block, a flower micelle microstructure is formed." The hydrophobic B blocks of the same polymer will associate, bridging various different flower micelles at a higher concentration, leading to the formation of transient network."' 19 When the concentration exceeds the critical percolation threshold, a physically crosslinked transient network is formed, yielding a viscous solution or a ge1,2022 The BAB triblock polymers with hydrophobic B blocks behave like surfactants in aqueous solution."' 23 As the hydrophobic B blocks need to overcome a very high activation energy to leave the core, the associated polymer flower micelles are often frozen structure.2I The size and pattern of the flower micelles can be finely tuned at the molecular level by manipulating the chemical composition, architecture, and molecular weight."
The structure of the polymers and molecular weight of each block of BAB
triblock copolymers plays a critical role to the rheology of the corresponding aqueous solution.
Therefore, the BAB
triblock copolymers have to be carefully designed and synthesized with well-controlled molecular weight." Poly(ethylene oxide) (PEO) is a widely used hydrophilic polymer due to its high water

3 solubility and biocompatibility, and poly(methyl methacrylate) (PMMA) is a promising hydrophobic polymer as it is biocompatibility, appropriate glass transition temperature, and high transmittance.16' 18 Amphiphilic block copolymers containing PEO as the hydrophilic blocks and PMMA as the hydrophobic blocks are of great interest due to their biocompatibility and broad potential applications.16' 24-28 BAB triblock copolymers poly(methyl methacrylate)-b-poly(ethylene oxide)-b-poly(methyl methacrylate) (PMMA-b-PEO-b-PMMA) were used here as representatives to study their association properties with varied molecular weight of PEO and PMMA blocks in aqueous solution.
Atom transfer radical polymerization (ATRP) has been extensively employed to synthesize BAB triblock copolymers.20, 26-29 However, ATRP is very sensitive to oxygen and require a large amounts of Cu(I) as a catalyst.3033 As a living radical polymerization method, ATRP has been extensively employed to synthesize block copolymers with well-controlled molecular weight (M).3323435 However, the apparent drawbacks of classical ATRP limit its applications in the industry, where, a relative high amounts catalyst, typically in the order of 0.1 ¨ 1 mol % relative to monomers, are required to achieve a well-controlled living radical polymerization process,32 resulting in a significantly large amount of catalyst in the final products.
As the catalysts are generally toxic, the removal is necessary fbr the further use of the final products. However, the removal of metal complex is time-consuming and expensive. Sometimes, the residues of the catalyst are very difficult to remove, which severely limits the application of the ATRP process.
Moreover, the catalyst used in the classical ATRP is metal complex with a low valence (i.e. 0.113r), which is unstable in ambient conditions. Therefore, the catalyst for classical ATRP should be purified before use and then stored in glove box filled with inert gas.
Another significant drawback of the classical ATRP is its sensitive to oxygen, and tedious air-removing procedures are required.
Several modifications of ATRP have been developed to overcome the drawbacks of classical ATRP, such as Activator Re-Generated by Electron Transfer (ARGET) ATRP.36-38 hi ARGET ATRP, metal complex in its high valence state (i.e. CuBr2) is employed and excess reducing agents were added to regenerate Cu(I) from Clan as the catalyst. Compared to classical ATRP, ARGET ATRP

4 requires a much lower concentration of Cu and is less sensitive to oxygen."' 39-4 As far as we know, there is no report on the synthesis of PMMA-b-PEO-b-PMMA via ARGET ATRP.
Herein, Br initiating sites were first introduced to both ends of the PEO
polymer chains to prepare the macroinitiators Br-PEO-Br with M. of 20k and 100k. The PMMA-b-PEO-b-PMMA
with designed molecular weight was then synthesized with Br-PEO-Br, ppm level of CuBr2 and excess ascorbic acid as macroinitiators, catalysts, and reducing agents, respectively. The molecular weight of the PMMA block was controlled by tuning the molar ratio of MMA to Br-PEO-Br and monomer conversion. The PMMA-b-PEO-b-PMMA aqueous solution was prepared via solvent exchange method, and their rheology properties in aqueous solution and the effect of the Mn of PEO and PMMA were studied.
SUMMARY OF THE DISCLOSURE
In one aspect, there is provided a method for preparing viscosity modifier with the structure of PMMA-b-PEO-b-PMMA via A RGET ATRP.
A further aspect of the disclosure related to the design of the molecular weight ratio of PEO and PMMA blocks.
Still a further aspect of the disclosure related to the control of the molecular weight of PMMA block by tuning the molar ratio of1VIMA monomer to Br-PEO-Br macroinitiator.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure is illustrated with reference to the following figures and table, in which:
Figure 1 is a schematic representation of the synthesis of PMMA-b-PEO-b-PMMA.
Table 1 summarizes the structure and corresponding characterization results of P MMA-b-PEO-b-P MMA.
Figure 2 shows (A) the FTIR spectra of P1 and P2; (B) the 1H NMR spectra of PE020k, P1, PE0100k, and P2 Figure 3 shows the FTIR spectra of P1, P2, P3, P4, P5, P6, P7, and P8 Figure 4 shows the 111 NMR spectra of P1, P2, P3, P4, P5, P6, P7, and P8 = Figure 5 shows the surface tension of PMMA-b-PEO-b-PMMA aqueous solution as a function of concentration Figure 6 shows the optical images of P3, P4, and P5 triblock copolymers aqueous solution at the concentration of 10.0 wt. % or 3.6 mM
Figure 7 shows the G' andG" ofP 3 ,P4 and P5 aqueous solution in respect to the frequency at the concentration of 10 wt. % (A) and 3.6 mM (C); viscosity of P3, P4, and P5 hydrogels as a function of shear rate at the concentration of 10 wt. % (B) and 3.6 mM
(D) Figure 8 shows the optical images of P6, P7 and P8 triblock copolymers aqueous solution at the concentration of 10.0 wt. % or 0.88 mM
Figure 9 shows the G' and G" of P6, P7 and P8 aqueous solution in respect to the frequency at the concentration of 10 wt. % (A) and 0.88 mM (C); viscosity of P6, P7 and P8 aqueous solution as a function of shear rate at the concentration of 10 wt. % (B) and 0.88 mIVI (D) DETAILED DESCRIPTION OF THE DISCLOSURE
This disclosure provides a method to prepare viscosity modifier with PMMA-b-PEO-b-PMMA triblock copolymer structure via ARGET ATRP. The ARGET ATRP was performed with ppm level amount CuBr2 as catalyst and ascorbic acid as the reducing agent to overcome the sensitivity to oxygen of traditional ATRP. The approach is different from previous traditional ATRP procedure. It is believed that the ARGET ATRP is more promising that ATRP
for scale-up.
The present disclosure provides a method to tune the molecular weight of the PEO and PMMA
, blocks. PEO with different molecular weight is commercially available. Therefore, the molecular weight of PEO block could be tuned by choosing commercially available PEO as the starting chemical. a-bromoisobutyryl bromide (B EBB) was used to esterify PEO to introduce Br initiating sites on the both ends of PEO to obtain Br-PEO-Br. The molecular weight of PMMA block in PMMA-b-PEO-b-PMMA was tuned by the molar ratio of MMA monomer to Br-PEO-Br macroinitiator. The schematic route for the synthesis of PMMA-b-PEO-b-PMMA was shown in Figure 1.
The molecular weight design of the triblock copolymers PMMA-b-PEO-b-PMMA was summarized in Table 1. PEO with molecular weight of 20,000 and 100,000 g/mol was chosen as the starting materials. The macroinitiator Br-PEO-Br (P1 and P2) was obtained by esterification of PEO with BIBB. The successful synthesis of Br-PEO-Br was confirmed by the FTIR
and I H NMR
spectra, as shown in Figure 2. The PMMA-b-PEO-b-PMMA was synthesized via the ARGET
ATRP of MMA with Br-PEO-Br (P1 and P2) as the macroinitiator. P3, P4, and P5 was synthesized with P1 as the macroinitiator, therefore, the molecular weight of PEO in P3, P4, and P5 is 20,000 g/mol. The target molecular weight of PMMA in P3, P4, and P5 are 5,000, 10,000, and 20,000 g/mol, respectively. The molar ratio of MMA monomer to P1 in the ARGET ATRP
process for the synthesis of P3, P4, and P5 were 100, 200, and 400, respectively. P6, P7, and P8 was synthesized with P2 as the macroinitiator, therefore, the molecular weight of PEO in P6, P7, and P8 is 100,000 g/moL The molar ratio of MMAmonomer to P2 in the ARGET ATRP process for the synthesis of P6, P7, and P8 were 400, 1000, and 2000, respectively. The target molecular weight of PMMA in P6, P7, and P8 are 20,000, 50,000, and 100,000 g/mol, respectively. The successful conduction of AR EGETATRP and synthesis of PMMA-b-PEO-b-PMMA were confirmed by the FT1R
spectra, as shown in Figure 3. The macular weight of PMMA block in PMMA-b-PEO-b-PMMA
was calculated by the NMR spectra (Figure 4) with the molecular weight of PEO as the reference.
The molecular weight information and monomer conversion are summarized in Table 1.
The triblock copolymer PMMA-b-PEO-b-PMMA aqueous solutions were prepared by dissolving the triblock copolymer in THF, followed by the slow addition of water at a rate of one drop every seconds under vigorous stirring. After the removing of THF via rotary evaporation, the triblock copolymer aqueous solutions were obtained. As shown in Figure 5, the surface tension of all the triblock copolymer aqueous solutions decreased dramatically with concentration at the very dilute range from 0 to 0.003 g/L. The surface tension of the solution dropped from 72 NIm to about 63 N/m at the concentration of 0.003 g/L.

The optical images of P3, P4, and P5 triblock copolymers aqueous solution at the concentration of 10.0 wt. % or 3.6 mM are shown in Figure 6. Their storage (G') and loss (G") shear moduli in respect of the frequency, viscosity in the respect of the shear rate are shown in Figure 7. The magnitude of the G' and G" of P3, P4 and P5 aqueous solution at 10 wt. %
followed an order of:
P3> P4> P5. At the concentration of 3.6 mM, the magnitude of G" followed an order of P3 > P4>
P5, while the magnitude of G' followed a different order of P4 > P3 >P5.
According to the comparison, P3 displayed the best rheological profiles among P3, P4, and P5.
In P3, The M. of PEO block was about 5.4 times of the M. of PMMA block.
The optical images of P6, P7, and P8 triblock copolymers aqueous solution at the concentration of 10.0 wt. % or 0.88 mM are shown in Figure 8. Their storage (G') and loss (G") shear moduli in respect of the frequency, viscosity in the respect of the shear rate are shown in Figure 9. The magnitude of viscosity of P6, P7 and P8 aqueous solution at 10 wt. % followed an order of P7>
P8 > P6. At 0.88 mM, the G', G" and viscosity of P6, P7 and P8 aqueous solution followed an order of P8 >P7 >P6 at the same frequency. From the comparison, P7 exhibited the best rheological profiles among P6, P7 and P8. In P7, the A of PEO block was about 5.2 times of the M. of PMMA
block.
Moreover, P4 and P6 possess similar M. of the PMMA blocks (7.8k for P4 and 7.9k for P6) and different A of the PEO blocks (20k for P4 and 100k for P6). PMMA-b-PE020k-b-PMMA is more favorable to form a hydrogel than PMMA-b-PEO100k-b-PMMA at the same weight percentage concentration.

Example 1-Preparation of macroinitiatnr Br-PE020k-Br (P1) For the preparation of Br-PE020k-Br (P1) with the Mõ of PEO of 20k, the PEO
(Mg = 20k, 100g, mmol) was dissolved in DCM (400 ml), followed by the addition of TEA (2 g, 20 mmol) and DMAP (2.44 g, 20 mmol). The mixture was cooled to 0 C with ice-bath. Then the solution of ' BIBB (4.33 g, 20 mmol) in DCM (50 ml) was added dropwise in 30 mins.
The esterification was conducted at room temperature. After 24 hours, the Br-PE020k-Br was precipitate in 10-fold cold diethyl ether under stirring. The polymer P1 was filtered and washed with diethyl ether three times, and the white powder product P1 was obtained by drying at 40 C under vacuum for 12 hours.
Example 2-Preparation of macroinitiator Br-PE0100k-Br (P2) For the preparation of Br-PE0100k-Br (P2) with the M. of PEO of 100k, the esterification of = PEO (Mg = 100k) by the similar procedure of P1. A viscous PEO solution was obtained by dissolving PEO (Mg = 100k, 50 g, 0.5 mmol) in DCM (800 mL). Then TEA (0.4 g, 4 mmol) and DMAP (0.5 g, 4 mmol) was added. After the solution was cooled to 0 C in an ice-bath, the solution of BIBB (0.87 g, 4 mmol) in DCM (30 mL) was added dropwise over a 30 min period. Then the esterification was conducted at room temperature for 24 hours. The Br-PE0100k-Br was precipitated in 10-fold cold diethyl ether under stiffing. After filtering and washing with diethyl ether three times, the final product P2 was obtained by drying in the oven at 40 C under vacuum for 12 hours.
Example 3- The synthesis of PMINIA-b-PE020k-b-PMINIA (P3, P4, and PS) P1 was used as the macroinitiator to synthesize PMMA-b-PE020k-b-PMMA with various M.
of PMMA blocks via ARGET ATRP. The target molecular weight of PMMA blocks in P3, P4, and P5 were designed as 5k, 10k and 20k g/mol, respectively. Br-PE020k-Br (10 g, 0.5 mmol) was dissolved in the mixture of toluene (100 ml) and methanol (20 ml), followed by the addition of methyl methacrylate (MMA, 5 g for P3, 10 g for P4, and 20 g for P5), bipyridyl (78 mg, 0.5 mmol), and CuBr2 (2 mg, 0.01 mmol). The mixture became green due to the present of Cu(II). After purging nitrogen for 20 mins, ascorbic acid (88 mg, 0.5 mmol) was added, and the mixture immediately turned brown due the formation of Cu(l). After purging nitrogen for another 20 mins, the temperature was raised to 70 C to perform the polymerization. After 24 hours, the polymer was precipitated in excessive diethyl ether and washed with diethyl ether three times. The final products were obtained by drying at 40 C under vacuum for 12 hours. The molar ratio of MMA monomer to Pt in the ARGET ATRP process for the synthesis of P3, P4, and PS were 100, 200, and 400, respectively.
Example 4- The synthesis of PMMA-b-PE0100k-b-PMMA (P6, P7, and PS) P2 was used as the macroinitiator to synthesize PMMA-b-PE0100k-b-PMMA with varied M.
of PMMA blocks via ARGET ATRP. The target molecular weight of PMMA block in P6, P7, and P8 were designed as 20k, 50k and 100k g/mol, respectively. P2 Br-PE0100k-Br (10 g, 0.1 mmol) was dissolved in the mixture of toluene (120 ml) and methanol (50 ml), followed by the addition of methyl methacrylate (MMA, 4 g for P6, 10 g for P7, and 20 g for P8), bipyridyl (78 mg, 0.5 mmol), and CuBr2 (2 mg, 0.01 mmol). The molar ratio of MMA monomer to P2 in the ARGET
ATRP process for the synthesis of P6, P7, and P8 were 400, 1000, and 2000, respectively. After purging nitrogen for 20 mins, ascorbic acid (88 mg, 0.5 mmol) was added. After purging nitrogen for another 20 mins, the polymerization was conducted at 70 C. After 24 hours, the polymer was precipitated in excessive diethyl ether and washed with diethyl ether twice.
The final products were obtained by drying at 40 C under vacuum.
Example 5- The preparation of triblock copolymer PMMA-b-PEO-b-PMMA
aqueous solution The triblock copolymer aqueous was prepared via THF solvent exchange method.
The preparation of triblock copolymer aqueous liquid at a concentration of 10 wt.
% is described as an example here. Triblock copolymer (1 g) was dissolved in THF (10 ml). Then Millipore water (9 g) was slowly added at a rate of 1 drop every 5 seconds under vigorous stirring.
The triblock copolymer hydrogel was obtained by removing THF via rotary evaporation under vacuum at room =

temperature for 3 hours. The triblock copolymer hydrogels at different concentration were prepared with the different amounts of triblock copolymers via the same procedure.What is claimed is:
1. PMMA-b-PEO-b-PMMA with designed molecular weight of PMMA and PEO blocks were synthesized via ARGET ATRP. The ARGET ATRP was performed with ppm level amount CuBrz as catalyst and ascorbic acid as the reducing agent to overcome the sensitivity to oxygen of traditional ATRP.
2. The molecular weight of PMMA block was controlled by changing the molar ratio of MMA monomer to Br-PEO-Br macroinitiator.
3. At the same molecular weight of PEO block, the PMMA-b-PEO-b-PMMA aqueous solution showed the highest viscosity at the same weight percent when the molecular weight of PEO to PMMA block was about 5.

Hor.f.,,..0,)4...1 0H It_ B,...),,rar TEA,DMAP
Cll.( 0 DCM Br PEO BIBB Br-PEO-Br Cuar,/bipyridel ., Br + Xy,ascorbic acid I, 71, n . m toluene/methanot MM A PMMA-b-PEO-13-PMMA
Figure 1 M. of PEO Molar ratio of Target /4, of M. of MMA
M. of PMMA
Sample Structure block MMA to PMMA block polymer c,onversio block (g/mol) (g/mol) macroinitiator (g/mol) (g/mol) n (%) Pi Br-PEO-Br 20k / / / 20k /
P2 Br-PEO-Br 100k / / / 100k /
PMMA-b-P3 20k 100 5k 3.7k 27.4k -- 74.0%
PEO-b-PMMA
PMMA-b-P4 20k 200 10k 7.8k 35.6k 78.0%
PEO-b-PMMA
PMMA-b-P5 20k 400 20k 11,1k 42.2k -- 55.5%
PEO-b-PMMA
PMMA-b-P6 100k 400 20k 7.9k 115.8k 35.0%
PEO-b-PMMA
PMMA-b-P7 100k 1000 50k 19.3k 138.6k -- 38.6%
PEO-b-PMMA
.
PMMA-b-P8 100k 2000 100k 32.2k 164.4k 32.2%
PEO-b-PMMA
Table 1 , , A 11097 ' ' B 4 3 1 11.4551w P110201mid PI
13, r b a 4/ /,. 22731'02E010t2 mid 961 o c r 841 i 2882 1466 v , a, 4 P2 c 1735 ,, to p2 PE01013k _ _k L
9 b ________________________________________ ) .....Ø.....-, PI
P.1 k.16,...õ.. PE020k 1 Wavenumbera (em4) 4.1 39 3.2 3.3 3-2 31 29 2.7 2.3 1.3 2./
19 1.2 4 (00.30 Figure 2 .
A _______________ i B _______________________________________ .,..

. .., k.L

I j N 1L
,..) :
i ___,A,-...- -)1 = N

JLi i _12_4A,..._ . / 4 i .1.1j1 , a i µt Likõ,..._ Wavenumbera (cm") SVaverumbers (cm) Figure 3 d . 4 = d A , Et Br . b 435 31 te b 273 e =
d d a, h 1.:___ e ,_)=-_, a, h .:L __ ,_.L......, c I
------ ---,--7`..-__-." --A-______________________ ...,__._....,,.--"--. k.

--..,-...- ___ ..-____-...-.4.-. __ a..0 3.0 3.8 3.7 3.8 3.5 3.4 2.1 2.0 3.0 La 1.7 1.I LO 11.1 09 13.7 0.I 90 22 is 5.116 3.3 3.4 3.312 3.0 10 1.8 1.71110 0.2 MD 12 96 3 (2200 6120813 ..
Figure 4 , e 72- , . -.-- P4 --.
E
"2 ¨ 64 -.0 ,...,-.- = .7....---..
to) c 60 - -........-, al .4., =
ce g 56 -t (3 -=
-. i = i= i= __ t= 1 0.00 0.05 0.10 0.15 0.20 0.25 Concentration (giL) Figure 5 -A P3 P4 , 0201 P5 MI
- - ,;.,0,-.4õ, = -....r.-,,ic- = . -',".'' ..." ..s.,,,?-tiv.
..Ar ' ' i.pit.!Niiiht: lo .o wt .% 431..9.w&%- 10.0 wt...%
is,.i wt .%
..citriMiEt.' 2 8 rAll = " 4:841.6-e) 2.4 m VI. .' 1.401M."'!
''''= = V4!:-+ ..4µ. -E., E .E, 1, '"'"2.'" '-',;,--- n' =
==,,,;,..,r,,O, t...::õ.....4 ..:14-4...,,,,), 2,_..-..
,.7õ, = f:,.4õ-:.,=::',.--:,=-.1 ' sz, 't-='..=,. ;=7?;'.. * -7..:=;=...4:--.14. /E1,-,41:4'.,114:1- f.' ,-,-; E -r.'; -1:::".;e.fiti,õ.
.--,f',,i,µ,4;i = -. -f",e4 ;':;;;;-2, ie,.,,,,t, =-err;',:' retWiNieS:-, B ft------:.:-..4.; A-7r" =is:":'.7"-;:.,4 ,.;:.'":77,.,';'".,,.-.-.,. i '''' ' 'WI
:114t4i.':if4 :,,-;;:-..,,o1A ;;.1.7:41::=.'::.;k,,. ,..
-:. 1,.= ! :::/,',õct.,=.: i L64,140 '''µ,''44:EE'-:-$ 'E'-' rn ''''''4-'"' "=-,.::µ5.::- -.:, 1---' , ' . ,._ . I.'. ', .'..4.:1'7'"a'W - .4 = ., -'4,:E-'..;`.1..-'0'..-itE ' .
-71.N.1-4-: '''' ''',-'44e..`a'-''1, . '-' .4 ,!;e4'.....tii..13. --=::.--- -1 - 4 . ' ' ''-':.'' =
1.i..==:',.5...* ovv.=,,,,. ' -. = -114.0F, .... .s.,,,,, -- =
s .--.-õ,....-/- k....)0. i, ! 4,....= ,, .. . - . =
: .
P3 P4 ) = P4 ;',.. P5 Figure 6 14 , A 1000, g woo ¨ P3, 10.0 wt.%. 3.6 m1,1 -e-1,4, 1 0.04.41.94,2A mM11 . . P5, 10.0 wt.14, 2A mrn 1a0.
=-= 11:10-b 10 er b 1, ,irret.$1,3.1mM
e"er". -e-RtMlOwl.96 0.1 P4, 0', mm PS, 0', 10%94%, 2A OA
10 well 2.4 mM =

frequency(11z) ShearRate fits) ...-P300.0v4.1%35m04 0.1000 30 44.14. 3.0 "4 1000. Pq. 13.4 3.4 mkt 4.4444.--..-:-"ft-,Tr, 100 M.'', 3 41r4 es' =
g.-. P3, 134 w146. 34,144 .02, 190 p4, 110 v,L%. 3.6 mt4 -,-=== P4. 0", 1101.4 4, 3.0 =
103.
" " ¨ õ = ====.
0.1 1 10 Frequency 1114 Sheer Rate (1/s) Figure 7 , "1:,,õ =
=
.1.0,0 wt.% 10 0 Mit.% 12.2 Wt.% 10.0 cut.1, = = 14.4 wt.%
&as rk-VP 3.72 mN1 Clas rnf11 0.
= ,:fV(N =

Ipaminuriw B r4144, =
. .
-=
, P6 P7 P7 LZiwi P8 = =
Figure 8 A 1 - -4'f'46"11*4 -\ int.%, 0.6\ 001:
mm:
P8, 10.0 1 mM
b I; 0.01 - PO, 0%10.0 wt.%, 0.88 mM 2 =
- G., 100 wt.%, 0.72 m M
1E-3- G10.0 wt.%, 0.72 mM
mM
1E-4 - . __ .
0.1 1 10 1 10 Frequency (Hz) Shear Rate (Its) D 10.0 wt.%, 0.88 mM
10, ¨ 0 - PT, G`, 12.2 wt.% 0.88 mM
1E-3 -0-P7, G`,12.2 wt.%, 0.68 lett ==========
- G", 144 wt.%, mM
0 1 1 10' = Frequency (Hz) Sheer Rate Wet Figure 9 References:
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