Thursday, Jul. 24, 2014
76 ° Light Rain
|Student||Alison Washington ‘15|
Dr. Kevin Kittredge|
|Course||Chemistry 489: Research Methods in the Natural Sciences|
A study of the rates of release of methylene blue (MB) from hyperbranched poly(acrylic acid)/poly(allylamine hydrochloride) (PAA/PAH) films at 38°C and pH 7.15 is reported. Hyperbranched were synthesized in a layer-by-layer fashion with an intercalated organic dye, methylene blue, and cured at 150 °C for 15 min. The films were approximately 575 Å in thickness as measured by profilometry. The rates of release were measured by UV-visible spectroscopy by monitoring the appearance of methylene blue at 665 nm. Two processes have been observed, the first is for the release of methylene blue from the film and the second, slower process is undetermined. We are examining two potential processes to determine which corresponds to the slower rate, hydrolysis of the free methylene blue in solution or decomposition of the film.