User:Dominique Brager/Notebook/481 Notebook/2017/02/08

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  • Took beads out of freeze dryer
  • Boiled cabbage leaves
  • Swelled Beads


  • Freeze dried beads were black and clumped into solid rocks. Potentially the lower pressure was enough to let the hydrolysis reaction happen.
  • Weighed Beads
  • Swelled Beads
  • Places beads in containers with enough water to coat them


  • Mass of Beads
  • 10% Beads: 0.811 g
  • 25% Beads: 1.007g
  • 40% Beads: 1.123g
  • Beads Observations
  • Were in solid clumps
  • Poking them with a stick and shaking them did not separate them into beads
  • Beads were a blackish-greenish color
  • Upon placing the beads into water they separated a little into beads and turned a lighter green color
  • After about half an hour of sitting in water, water solution had a pH of about 1 according to pH test.
  • 40% beads were fasted to turn green.
  • Turned a richer, greener green
  • 25% Beads took longest to turn green
  • Color somewhat between 40% and 10%
  • 10% Beads
  • Turned a yellower green color (more like seaweed)

  • Cabbage Dye
  • Boiled dye until most of pigmentation came out
  • Checked effect of pH on color
  • Dye is neutral
  • Checked effect of pH on dye color
  • Beaker on the left is acidic. Beaker in the middle is neutral. Beaker on the right is basic.
  • Ran UV-Vis on Dye and Serial Dilutions as follows: Stock solution, 4:1 Stock to water, 3:2 Stock to water, 2:3 Stock to water, and 1:4 Stock to water.
  • Neutral Dye absorbed between 545-548 nm
  • Got the following UV-Vis Spectrum:
  • Made trendline for absorbance of serial dilutions. Percentages are based of stock solution. 100% = same concentration as stock solution. 20% is 1:4 stock to dye. Etc.


Link to patent that explains discoloration in PVA