User:Anh Do/Notebook/CHEM 481 Polymer/2017/02/03

Project name

Main project page Previous entry      Next entry

Task list Synthesize beads with 40% clay content Freeze-dry the beads made on Wednesday Synthesize beads with 40% clay content *Create a solution of PVOH, bentonite solution, water, and HCl. 1.25g PVOH, 27 mL bentonite solution, 15mL HCl, 13mL water Place this solution on a hot plate and heat/stir until everything has dissolved (for 30 mins). Add 30 mL of this solution to a 100 mL solution of ethyl acetate in a dropwise manner stirring at 380 rpm. Add 1.5 mL of glutaraldehyde and stir at 260 rpm for 3 minutes. Add 1.5 mL of glutaraldehyde and stir at 260 rpm for 7 minutes. Put the solution and the beads to two 50mL falcon tubes. Centrifuge the falcon tube at 3000rpm twice for one minute and then five minutes. Remove the solution in the falcon tube and add in water. Freeze-dry beads Procedure Decant the beads' falcon tubes, make sure the amount inside is about 20mL to 25 mL Use a needle to poke holes at the top of the falcon tubes (about 10 to 12 holes) Put the falcon tubes in a freezer at -80°C for 30 minutes Take the falcon tubes out and place them in the freeze-dry machine Notes Monitor the flow of the solution inside the burrette closely because this solution is much more viscous than the ones with 10% and 25% clay content. The solution for 40% clay content usually stopped flowing down drop-wise after 45 seconds, and researcher should adjust the burrette accordingly. The beads with 40% clay did not separate well with only one minute of centrifuging