1. Propagation of Interfacially Active Nanohybrids
Stability of Dispersions
ASL AN M AL EKI
2/19/2013

2. Agenda
 Methods
 Measuring Tools
 Stability Experiments:
 Experiment 1: 200 ppm PVP-40K & 1600 ppm HEC-10 & 100 ppm P/MWNT
 Experiment 2: 200 ppm PVP-40K & 1600 ppm Gum Arabic & 100 ppm P/MWNT
 Experiment 3: 200 ppm Gum Arabic & 1600 ppm HEC-10 & 100 ppm P/MWNT
 Xanthan Gum Preparation
 Conclusion
 Future Works
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3. Method of preparation
Intermediate Dispersion:
P/MWNT & Primary Polymer
Sequential Dispersion Sonicate 2 hr.
Preparation
 Purified Multi-walled CNTs Add Secondary Polymer
 Polymer Dispersants
 Brine (8% NaCl & 2% CaCl2) Sonicate 30 min.
10%, API
Centrifuge 2 hr. @ 2000 rpm
Filtration @ 1 um
Final Dispersion:
PMWNT + 2 Polymers
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4. Measuring Tools
Testing Dispersion Stability:
Measurement of particle loss as a function of time
Quantify loss with turbidity or UV-Vis
Initial Reading
1. 1st Hour
2. 3rd Hour
3. 12th Hour
4. 24th Hour
5. 1st Day
6. 2nd Day
7. 3rd Day
8. 5th Day
9. 7th Day
10. 1st Week
11. 2nd Week
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5. Experiment 1 – with Turbidity
Polymers: API Brine Based
Primary – 200 ppm PVP-40K
Secondary – 1600 ppm HEC-10
P/MWNT – 100 ppm
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6. Experiment 1 - Data
200 ppm PVP-40K
1600 ppm HEC-10
100 ppm P/MWNT 50C (Turbidity vs. Time)
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8
7
6
TURBIDITY (MΩ)
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4
3
2
1
0
0 15 30 45 60 75 90 105 120 135 150 165 180 195 210
TIME (HOURS)
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7. Experiment 1 – with UV-Vis
Polymers: API Brine Based
Primary – 200 ppm PVP-40k
Secondary – 1600 ppm HEC-10
P/MWNT – 100 ppm
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8. Experiment 1 - Data
200 ppm PVP-40K
1600 ppm HEC-10
100 ppm P/MWNT
3.000
2.900
2.800
Absorbance Room
2.700
Absorbance (50C)
ABSORBANCE
2.600
2.500
2.400
2.300
2.200
2.100
2.000
0 100 200 300 400 500 600 700 800
TIME (HOURS)
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9. Experiment 2 - Description
Polymers: API Brine Based
Primary – 200 ppm PVP-40k
Secondary – 1600 ppm Gum Arabic
P/MWNT – 100 ppm
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10. Experiment 2 - Data
200 ppm PVP-40k
1600 ppm Gum Arabic
100 ppm P/MWNT
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11. Experiment 3 - Description
Polymers: API Brine Based
Primary – 200 ppm Gum Arabic
Secondary – 1600 ppm HEC-10
P/MWNT – 100 ppm
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12. Experiment 3 - Data
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13. Xanthan Gum Preparation
2000 ppm Xanthan Gum @ 10% API
Method:
1. 8 min @ high speed
2. 8 min @ med. speed (Wait 24 Hours) then 8 min @ med. speed
3. 8 min @ med. Speed, then sonicate 30 min.
4. 8 min @ med. Speed, then sonicate 1 hr.
No gel or cake formation
Filter each at 1 um observed on filter for any
method
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14. Viscosity
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15. Conclusions
 Dispersion Stability
 UV-Vis  less fluctuation in data than turbidity
 Negligible difference in stability at 50oC
 All samples stable for 2 weeks
Xanthan Gum Preparation
 Highest viscosity with lowest change after filtration:
med speed 8 min (wait 24 hr) med speed 8 min
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16. Future Work
Dispersion Stability
 PVP-40k only dispersion
• Compare DI vs. 10% Brine @ Room Temp & 50oC
 Xanthan Gum as secondary dispersant
Polymer Thermo-Stability
 Effect of temperature on polymer viscosity to
determine time/temperature at which degradation
occurs.
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17. Acknowledgement
Dr. Ben Shiau
Dr. Jeffrey Harwell
Dr. Peter Lohateeraparp
Master Danny Swatske
Master3 Tzu-Ping Hsu
ASL Lab Crew
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18. Questions & Answers
T H AN K YO U F O R YO U R T IM E
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