# User:Karlena L. Brown/Notebook/PVOH Research/2012/09/02

PVOH Research Main project page
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## OBJECTIVES

1. Label and remove previous PVOH films from Teflon dishes
2. Prepare more PVOH (MW 22K) films with 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.
3. Determine ratios and percentages in which solid acids will be added to the PVOH (MW 22K)

## Deviated Acidic PVOH Film Preparations 3

Deviated HCl PVOH films prepared in water:

• In 10mL beaker, weigh out ~ 0.5 grams PVOH (MW 22K)

(Actual mass = 0.5181g)

• Then, using a graduated cylinder add ~ 3mL 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 = 0.0582g)

• Repeat this procedure again; however use succinic acid as substitute for maleic acid.

(Actual PVOH mass = 0.5163g) (Actual Succinic Acid mass = 0.0571g)

Deviated H3PO4 PVOH films prepared in water:

• In another 10mL beaker, weigh out ~ 1 gram PVOH (MW 22K)

(Actual mass = 1.0054g)

• 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 = 0.1565g)

• Repeat this procedure again; however use succinic acid as substitute for maleic acid.

(Actual PVOH mass = 1.0125g) (Actual Succinic Acid mass = 0.1519g)

Standard PVOH Film Protocol:

• After adding and combining PVOH (MW 22K) 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
• As solutions heated, beakers containing the strong acids (HCl) left burn marks at the bottom of solution -- slightly tinting the PVOH solutions brown
• While transferring solutions to Teflon dishes, loss of sample within the small beakers (sample loss = incomplete sample transfer)
• PVOH (MW 22K) films w/just liquid acids were harder and more rigid than PVOH (MW 22K) films w/ both liquid and solid acids added.