User:Melissa Novy/Notebook/CHEM-581/2012/11/16

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  • Standardize 1 M NaHCO3 solution.
  • Soak PVOH (MW 22000) in HPLC grade H2O to determine change in mass due to swelling.
  • Soak PVOH (MW 22000), 1 mL glutaraldehyde, 1 mL porphyrin in 2 wt% H2SO4 until the film turns green. Then soak the film in salt solution and take UV-vis of the film.

PVOH (MW 22000) Film Swelling

  • Change in mass of PVOH (MW 22000) films after soaking in 10 mL HPLC grade H2O for three days.
Crosslinked Film Date Prepared Initial Mass [g] Final Mass [g] ΔMass [g] % Change []
PVOH(22k),1mLGA,1mLPP,less colored10/24/20120.0140.02410.010172.14285714
  • The films that displayed the smallest percent change in mass were PVOH(22K)+0.8wt%GA+100%CECMT (exchanged with CuSO4) and PVOH(22K)+1mLGA+1mLPP.
  • The films that displayed the largest percent change in mass were PVOH(22K)+0.5mLGA+100%CECMT, PVOH(22K)+0.5mLGA+NaMT, and PVOH(22K)+0.5mLGA+1mLPP.
  • Effect of ion exchange?
  • It appears that adding 0.5 mL of glutaraldehyde to the films does not induce sufficient crosslinking to prevent swelling. However, 1 mL of glutaraldehyde seemed to reduce the degree to which the films swelled.
  • Overall, most films displayed about a 100% increase in mass. In other words, their mass approximately doubled due to swelling.

Standardization of NaHCO3

  • Protocol
    1. Weigh out 20 g of potassium hydrogen phthalate (KHP).
    2. The mass was divided into thirds, and then dried in the oven at 90°C for 48 hours.
    3. Each sample was divided in half again to give six samples of KHP total.
    4. One sample was placed in a 100 mL beaker and 2 drops of bromothymol blue was added.
    5. 1 M NaHCO3 was poured into a titration buret and the initial volume was recorded.
    6. The KHP was titrated with the NaHCO3 solution until the solution in the beaker turned blue and stopped fizzing.
    7. The process was repeated for two more KHP samples.
    8. The number of moles in the NaHCO3 solution was calculated.


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