User:Elizabeth Ghias/Notebook/Experimental Chemistry/2013/02/15

Experimental Chemistry

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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