User:Karlena L. Brown/Notebook/PVOH Research/2013/02/01

PVOH Research

Main project page Previous entry      Next entry

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.