OBJECTIVES
- Continue preparing polyvinyl alcohol hydrogels for experimental analysis
- Prepare and replenish new surfactant exchanged clays
PVOH 130K Prepared Hydrogel Samples
PVOH vs. Clay Ratio
|
Clay Selection
|
PVOH 130K Mass (g)
|
Actual Clay Mass (g)
|
H2O Added (mL)
|
Dye Concentration (mM)
|
Dye Amount Added (μL)
|
90:10 |
50% CEC NaMT w/ Bu3HdP+ |
0.92966 |
0.09990 |
6.0 |
92 |
65.5
|
50:50 |
50% CEC NaMT w/ Bu3HdP+ |
0.50610 |
0.50010 |
6.0 |
165 |
36.4
|
90:10 |
NaMT |
0.89910 |
0.10020 |
6.0 |
92 |
65.5
|
50:50 |
NaMT |
0.50070 |
0.49960 |
6.0 |
165 |
36.4
|
90:10 |
Laponite |
0.91610 |
0.10040 |
6.0 |
92 |
65.5
|
50:50 |
Laponite |
0.49900 |
0.50090 |
6.0 |
165 |
36.4
|
90:10 |
110% CEC NaMT w/ DMHXLBR |
0.89970 |
0.10050 |
6.0 |
92 |
65.5
|
50:50 |
110% CEC NaMT w/ DMHXLBR |
0.49920 |
0.49910 |
6.0 |
165 |
36.4
|
90:10 |
110% CEC Laponite w/ DMHXLBR |
0.90080 |
0.09990 |
6.0 |
92 |
65.5
|
50:50 |
110% CEC Laponite w/ DMHXLBR |
0.49980 |
0.49980 |
6.0 |
165 |
36.4
|
Preparations For Clay - Surfactant Exchanged Soils
(Important Information and Notes About Clay)
- Clay is made from silicon dioxide
- If ions within the clay are changed, then clay absorbance, color, and exchange functions are affected
(Such ions incldue: Al3+, Mg2+, Si2+, Li+, and Fe2+ or 3+,)
- In a 100mL closed cap beaker, weigh out ~ 2 grams of NaMT clay to do a 110% ion exchange with DMHXLBR
- Next, complete calculations to determine how much DMHXLBR will be needed to complete 110% exchange
1.9999 g NaMT x (92 meqv/100 g NaMT) x (1 mol DMHXLBR/1000 meqv) x (110/100)% x (431.45 g DMHXLBR/1 mol DMHXLBR) = 0.8732 g DMHXLBR
- Then add a stir bar along with ~ 25mL of both H2O and ethanol to the clay and surfactant DMHXLBR mixture
- Afterwards, cap the beaker and begin stirring the solution on a stir plate for ~ 1 week
(Repeat the entire process again in order to complete a 110% exchange with laponite clay and surfactant DMHXLBR)
- Complete calculations to determine how much Bu3HdP+ will be needed to complete 50% exchange
2.9672 g NaMT x (55 meqv/100 g NaMT) x (1 mol DMHXLBR/1000 meqv) x (110/100)% x (431.45 g DMHXLBR/1 mol DMHXLBR) = 0.7745 g DMHXLBR
(Repeat the entire process again in order to complete a 50% exchange with NaMT clay and surfactant, Bu3HdP+)
- Complete calculations to determine how much Bu3HdP+ will be needed to complete 50% exchange
2.0001 g NaMT x (92 meqv/100 g NaMT) x (1 mol Bu3HdP+/1000 meqv) x (50/100)% x (507.65 g Bu3HdP+/1 mol Bu3HdP+) = 0.4671 g Bu3HdP+
Surfactant Exchange Ratio
|
Clay Selection
|
Surfactant Selection
|
Actual Clay Mass (g)
|
Actual Surfactant Mass (g)
|
H2O Added (mL)
|
Ethanol Added (mL)
|
50% |
(NaMT) |
Bu3HdP+ |
2.0001 |
0.4676 |
25 |
25
|
110% |
NaMT |
DMHXLBR |
1.9999 |
0.79080 |
50 |
50
|
110% |
Laponite |
DMHXLBR |
2.9672 |
0.77470 |
50 |
50
|
Notes
- Two types of clay that were used included:
# Laponite
# Sodium Montmorrillonite (NaMT)
- Two types of surfactants that were used included:
# Tributyl hexadecyl phosphonium bromide (Bu3HdP+)
# Methyl 16 bromohexadecanoate (DMHXLBR)
- Surfactant exchanged clays were prepared based upon the exchange ratios and calculations.
- For the 110% CEC Laponite w/ DMHXLBR actually 50mL of each of both ethanol and water was used.
- For the 110% CEC NaMT w/ DMHXLBR actually 50mL of each of both ethanol and water was used.
- For the 50:50 110% CEC Laponite in PVOH 130K solution when making hydrogels, an extra 3mL of H2O was added; therefore, the dye amount added had to be increased, ~ 54.5μL of 165μM added.
- For the 50:50 110% CEC NaMT in PVOH 130K solution when making hydrogels, an extra 2mL of H2O was added; therefore, the dye amount added had to be increased, ~ 48.5μL of 165μM added.
- For the 90:10 110% CEC NaMT in PVOH 130K solution when making hydrogels, an extra 2mL of H2O was added; therefore, the dye amount added had to be increased, ~ 87.0μL of 92μM added.
|