OBJECTIVES
- Label and remove previous PVOH films from Teflon dishes
- Prepare more PVOH (MW 130K) films w/ both solid and liquid acid deviations (S - Maleic and Succinic; L - HCl and H3PO4) for film analysis: IR, DSC, solubility, crosslinking, acid catalyzed dehydration, film comparison, etc.
- Determine ratios or percentages in which solid acids (S - Maleic and Succinic) will be added to the PVOH (MW 130K) films
Deviated Acidic PVOH Film Preparations 4
Deviated HCl PVOH films in prepared in water:
- In 10mL beaker, weigh out ~ 1 grams PVOH (MW 130K)
(Actual mass = 1.0106g)
- Then, using a graduated cylinder add ~ 6mL H2O to the beaker
- Next, at the fume hood add two drops of hydrochloric acid (HCl) to beaker solution
- Afterwards, calculate and weigh out a ~10%wt equivalent of maleic acid
- Add maleic acid equivalent to the acidic PVOH solution
(Actual Maleic Acid mass = 0.1071g)
- Repeat this procedure again; however use succinic acid as substitute for maleic acid.
(Actual PVOH mass = 1.0215g) (Actual Succinic Acid mass = 0.1021g)
Deviated H3PO4 PVOH films in prepared in water:
- In another 10mL beaker, weigh out ~ 1 gram PVOH (MW 130K)
(Actual mass = 1.0373g)
- Then, using a graduated cylinder add ~ 6mL H2O to the beaker
- Next, at the fume hood add two drops of phosphoric acid (H3PO4) to beaker solution
- Afterwards, calculate and weigh out a ~15%wt equivalent of maleic acid
- Add maleic acid equivalent to the acidic PVOH solution
(Actual Maleic Acid mass = 0.1556g)
- Repeat this procedure again; however use succinic acid as substitute for maleic acid.
(Actual PVOH mass = 1.0178g) (Actual Succinic Acid mass = 0.1528g)
Standard PVOH Film Protocol:
- After adding and combining PVOH (MW 130K) in small beakers with H2O and all acids (HCl, H3PO4, maleic and succinic), add stir bars and prepare to stir solutions.
- On hot plate, stir and heat all beaker solutions at 70-80°C for ~ 12 min or until all solids dissolve.
- Once PVOH and acidic solids dissolve in solution, pour each solution in Teflon dishes to sit, cool, and dry in a fume hood for ~ 2 days.
Notes
- An additional 2-3 mL H2O was added to each solution to aid the dissolving of the PVOH
- Heat was reduced when solutions began to boil too rapidly
- While transferring solutions to Teflon dishes, loss of sample within the small beakers (sample loss = incomplete sample transfer)
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