User:Anh Do/Notebook/CHEM 481 Polymer/2016/09/14

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Follow up on previous beads formation experiment

  • The beads created from last experiment showed some of the beads sticking together. This is not favorable because we want the beads to be separated for solution to easily pass through the column of beads.
  • The two vials of beads in ethyl acetate were centrifuged at 3000 rpm for 1 minute
    • Make sure the two vials are approximately of the same mass
  • Take out as much solution as possible from the vials, leaving only the beads inside
  • Add water in and let the vials sit for 2 hours
  • Centrifuge the vials again at 3000 rpm
  • Remove the water and let the vials sit

Beads formation using clay solution

  • Create a solution of 2.5 g PVA, 0.275 g NaMT, and 30 mL 10% HCl.
    • Mass of PVA meassured = 2.5001 g
    • 0.275 g Bentonite powder is equivalent to 8.89 mL of 3wt% Bentonite solution
      • Volumn of Bentonite 3wt% solution: 0.275g*97mL/3g = 8.89 mL
    • Volumn of HCl = 30 mL, this effectively diluted the whole solution. However, the amount in moles of HCl is the same, which is more important.
  • Place this solution on a hot plate and heat/stir until everything has dissolved.
  • Add 10 mL of this solution to a 50 mL solution of ethyl acetate stirring at 240 rpm in a dropwise manner using a burette.
    • Initial: 34 mL
    • Final: 44 mL
  • Add 1 mL of glutaraldehyde and stir at 320 rpm for 3 minutes.
  • After 7 minutes, add 7 mL of sodium bicarbonate and stir for 3 minutes
  • Remove the solution, put it into 2 50 mL Falcon tubes.
  • Centrifuge the solutions for 1 minute at 3000 rpm twice.
    • Make sure the two vials are of approximately the same mass
    • Take out as much solution as possible from the vials, leaving only the beads inside
    • Wash the beads with water.
    • Neutralize the beads using NaHCO3 powder. Make sure pH~7.

Follow up on the film making procedure

  • Weigh the films
    • PVOH + 10% Bentonite + 0.5 mL of Glutaraldehyde: 1.24545 g
    • PVOH + 0.5 mL Glutaraldehyde: 0.53 g
  • Rinse the films with water
  • Place the films in the oven at 100 degree celsius
  • Take the films out of the oven and weigh them again
    • PVOH + 10% Bentonite + 0.5 mL of Glutaraldehyde: 0.47705 g
    • PVOH + 0.5 mL Glutaraldehyde: 0.06450 g
  • The swelling capacity is
    • PVOH + 10% Bentonite + 0.5 Glutaraldehyde: (1.24545 - 0.47705)/(0.47705) = 1.61073
    • PVOH + 0.5 mL Glutaraldehyde: (0.53 - 0.0645)/0.0645 = 7.21705 (This does not make sense!!!!!)

3% Bentonite Film cross-linking

  • Mass of film = 1.4308 g
  • Follow this protocol



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