Objective
To crosslink the films prepared last class, to try the new reaction with (S)-(-)-(3-Chloro-2-hydroxypropyl)trimethylammonium chloride
Description
Crosslinking Films
- Heat 5 beakers with 100 mL of 0.7 M HCl
- Once heated to 70 °C add the five films.
- Heat the films for 1 hour
- Prepare 5 solutions of 1.68 g sodium bicarbonate in 100 mL water
- Rinse the films in distilled water, then place in sodium bicarbonate solution.
- Allow to soak in bicarbonate solution for 15 minutes.
- Rinse films in distilled water and then dry to run DSC.
(S)-(-)-(3-Chloro-2-hydroxypropyl)trimethylammonium chloride Reaction
- Measure out 4 samples of 2 g PVOH (MW = 22,000)
- Measure out 0.85779 g (S)-(-)-(3-Chloro-2-hydroxypropyl)trimethylammonium chloride. Place in 5 mL 0.2 M NaOH prepared last class)
- Actual amount used = 0.8581 g
- Transfer 0.5 mL, 0.05 mL, and 0.005 mL into 4.5 mL, 4.95 mL and 4.995 mL 0.2 M NaOH, respectively (this means the 10% film will be slightly less than 10% but we can still calculate what percentage)→ using 10 mL total volume b/c were doing 2 gram scale. For 1 g scale use 5 mL.
- Place the 4 samples of PVOH in 5 mL
- Allow to soak in the NaOH for 30 minutes
- Add 1 sample PVOH to one of the ammonium chloride samples and allow them to mix for 1 hour
- If the PVOH is still soluble in NaOH, add acetone to precipitate it out. (keep water to a minimum)
- Then do a quick wash with ice water to get precipitate out extra ions
Data
No results were collected today
Notes
- When the acetone was added to precipitate out the modified PVOH, the PVOH precipitated out as a white solid (looked like cotton)
- The samples will be filtered next class
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