User:Anh Do/Notebook/CHEM 481 Polymer/2016/09/16

From OpenWetWare

Jump to: navigation, search
Project name Main project page
Previous entry      Next entry

Making beads using activated carbon instead of clay

  • Making the solution of 2.5 g PVOH, 0.275 g activated carbon, and 30 mL HCl
    • Mass of PVOH: 2.5005 g
    • Mass of activated carbon: 0.2752 g
    • Volumn of HCl: 30 mL
    • Stir the solution at 400 rpm and heat it up at 85 degree celsius until everything dissolves
      • Note: PVOH dissolves less readily in activated clay. Thus, the stirring speed and temperature needs to be increase. A wooden stick can also be used to
  • 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: 31.3 mL
    • Final: 41.3 mL
  • Add 1 mL of glutaraldehyde and stir at 320 rpm for 3 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
  • Add water in the tubes, making sure they are of the same mass
  • Centrifuge again

Making beads using 20% clay

  • Making the solution of 1.25 g PVOH, 10 mL of 3wt% clay, 13 mL 12.1M HCl, 30 mL of H2O
    • Mass of PVOH: 1.2502 g
    • Mass of clay: 1.25/4 = 0.3125 g
    • Volumn of clay: 0.3125*100/3 ~ 10 mL
    • Volumn of HCL: 13 mL (this is not a correct value)
  • Place the solution on a hot plate at 70 degree celsius and stir at 300 rpm
  • Repeat the procedure stated above
    • Initial: 40.7 mL
    • Final: 45.7 mL

DSC Data

(From Dominique's Notes)

DSC Data
Glass Transition (°C) Melting Point (°C) Heat of Melting (J/g)
PVOH 70.25 191.13 35.66
PVOH x-link 80.07 179.67 0.6426
PVOH x-link 10% clay 82.19 168.08 0.5314
  • no glass transition, melting point, or heat of melting determined for PVOH 10% Beads

Percent of PVOH not cross-linked:

  • PVOH x-linked film without clay:
0.6426J/g / 35.66J/g *100% = 1.8%
  • PVOH x-linked film with 10% clay:
0.5314J/g / 35.66J/g *100% = 1.49%

Notes

  • Volumn of HCL used is not correct
  • Higher concentration of clay requires higher stirring speed


Personal tools