Today's objective was to create 20% and 30% by composition clay-PVA beads and prep them in columns. We also want to begin more swelling trials.
Since we only have one trial for one film for swelling, we want to now collect at least 3 trials for each of the four films. Today, we tore off 2 more pieces of 0.5mL glutaraldehyde and PVA films (one was already collected on 9/9/2016), patted them dry, recorded the mass, and put them in the oven for 2 hours at 100°C to dry them. We repeated those steps with 3 samples of 1mL glutaraldehyde and PVA films.
The full procedure of the former large scale synthesis can be found on Mary's notebook entry.
- A solution of 2.5022g of PVA, 16.66mL of 3% by wt bentonite solution, 5.31mL of DI water, and 8.03mL of concentrated HCl (to create 30 mL of a 10% HCl in clay solution) was heated and stirred until all PVA beads were dissolved.
- The solution was then transferred to a burette.
- 10mL of the PVA-clay solution was added, dropwise, to 100mL of ethyl acetate, while stirring at 600rpm.
- 2mL of glutaraldehyde was added and the solution was stirred for 7 minutes.
- After 7 minutes, 7mL of sodium bicarbonate solution was added and stirred for 30 seconds.
- The solution was removed and put into 50mL Falcon tubes.
- The solution was centrifuged for 1 minutes at 3000 rpm.
- The liquid was pipetted out of the tubes and replaced with DI water to store.
The same procedure above for the 20% beads was used for the 30% beads, except the starting reagents were the following: 0.2500g of PVA, 0.7498g of bentonite, 21.97mL of DI water, and 8.03mL of HCl.
Preparing bead columns
The procedure used to prepare bead columns for the 20% and 30% beads can be found on last Friday's entry
Unfortunately, the 30% beads did not create as small of beads as the other bentonite weights, likely do to the higher clay composition causing the beads to be more "sludgey". The weights for the new bead columns can be found on the next notebook entry.