ASLAN MALEKI

04/18/2023

Propagation of Interfacially Active Nanohybrids

Stability of Dispersions

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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Sequential Dispersion Preparation

Purified Multi-walled CNTs Polymer Dispersants Brine (8% NaCl & 2% CaCl2)

10%, API

Intermediate Dispersion:P/MWNT & Primary Polymer

Sonicate 2 hr.

Add Secondary Polymer

Sonicate 30 min.

Centrifuge 2 hr. @ 2000 rpm

Final Dispersion:PMWNT + 2 Polymers

Filtration @ 1 um

Method of preparation

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Measuring Tools

Initial Reading 1. 1st Hour2. 3rd Hour3. 12th Hour4. 24th Hour5. 1st Day6. 2nd Day7. 3rd Day8. 5th Day9. 7th Day10.1st Week11. 2nd Week

Testing Dispersion Stability:Measurement of particle loss as a function of timeQuantify loss with turbidity or UV-Vis

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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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Experiment 1 - Data

0 15 30 45 60 75 90 105 120 135 150 165 180 195 2100

2

4

6

8

10

12

50C (Turbidity vs. Time)

Time (Hours)

Tu

rbid

ity (

MΩ

)

200 ppm PVP-40K1600 ppm HEC-10100 ppm P/MWNT

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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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Experiment 1 - Data

0 100 200 300 400 500 600 700 8002.000

2.100

2.200

2.300

2.400

2.500

2.600

2.700

2.800

2.900

3.000

Absorbance RoomLinear (Absorbance Room)

Time (Hours)

abso

rban

ce

200 ppm PVP-40K1600 ppm HEC-10100 ppm P/MWNT

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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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Experiment 2 - Data

200 ppm PVP-40k1600 ppm Gum Arabic100 ppm P/MWNT

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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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Experiment 3 - Data

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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.

Filter each at 1 um No gel or cake formation observed on filter for any method

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Viscosity

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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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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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AcknowledgementDr. Ben Shiau

Dr. Jeffrey Harwell

Dr. Peter Lohateeraparp

Master Danny Swatske

Master3 Tzu-Ping Hsu

ASL Lab Crew

THANK YOU FOR YOUR TIME

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Questions & Answers