User:Elizabeth Ghias/Notebook/Experimental Chemistry/2013/03/08

Experimental Chemistry

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Objective To modify PVOH with quaternary ammonium salt and to analyze DSC data from February and the agar plates prepared yesterday. Description (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 Agar Plate Analysis The agar plates were visualized to compare the relative amount of bacteria growth that occurred overnight. After being visualized, the plates were autoclaved and were disposed. DSC Data Analysis For DSC data analysis, glass transitions were found and any peaks present were integrated. Data Agar Plate Visualization For the agar plates, the only two plates that were observed to limit bacteria growth were plates 7 and 8, which both contained the highest amount of quaternary ammonium salt. DSC Results Notes