Derek Saxon is a junior chemistry major from Iron Mountain, Michigan. He is conducting research this summer on biopolymers with Professor Dean Katahira of the Chemistry Department at Ripon College as part of his involvement with the McNair Scholars Program. He is one of four Ripon College students sharing their stories of research internships and jobs over the course of this summer.
Combustion of Guncotton
Remember how I mentioned cellulose is the most abundant polymer on the planet? Well, cotton is just a bunch of cellulose fibers put together. This week, I was able to nitrate cellulose in the form of cotton. Nitration is the addition of an –NO2 group (and, in this case, replacing an –OH group). I was able to nitrate the cotton using a solution of concentrated sulfuric acid and nitric acid.
The nitro groups on the cellulose backbone cause a slight change in color (a yellow-brown) and a very noticeable change in combustibility. As you can see on the left, regular cotton is ignited with a candle. There’s not much to see as the flame is fairly small. On the right, the nitrocellulose – or guncotton for its replacement of gunpowder in some cases because of the reduced smoke production – is also ignited. Here, we can see the flame is about five times larger and much brighter.
This was an exploration of a derivative of cellulose (which means a change in structure) to study the characteristics of certain modifications. I also found a couple of really old paper this week – from the 1940s and 50s – that will be helpful in my research. It seems that carbohydrates were studied extensively in the early part of the 20th century, but not much has been done in this area of sugars since. More work is yet to come on polymerizing these compounds.
To read more from Derek and our other summer bloggers, click HERE.
To learn more about the McNair Scholars Program at Ripon College, click HERE.Tweet