Month: December 2014

 

Finally, at the end of the semester, the culmination of our scientific efforts has come to a head in one last experiment. Lorelei, Meg, and Nika, when presented with the opportunity to draft our own experiment in which to subject our fellow classmates, decided that an artistic approach would be the best idea. The various intricacies of paint, being a substance so near and dear to our hearts (all three of us study some version of art at NESAD), seemed to be the best thing to introduce our fellow students to. The problem with most paints, despite being one of the most popular forms of artistic expression, is that they don’t mesh so well with an environmentally-conscious philosophy. Oil paints are difficult to dispose of due to the harmful thinners and pigments they need to be mixed with, and acrylic paints do not easily biodegrade due to their plasticity. These components of course, serve a specific purpose. The rich pigment of oil paint is very desirable when creating a painting, as is the consistency of the paint achieved by mixing with harmful thinners. The plasticity of acrylic paints makes them very archival, allowing the paintings to last hundreds of years without needing any sort of restoration. The problem of course, is not necessarily when the paint is applied to the canvas, but when the paint is leftover and needing to be disposed of.

       This is where we came in. There are ways to mix your own paints, with various household items and a little bit of non-toxic store-bought powdered pigment. Our experiment focused on students creating their own environmentally-friendly paints in class and then comparing them to store bough acrylic and oil paints. Though there are many factors in play when it comes to what makes a good paint, such as color, consistency, archivality, we focused on the opacity of the paint, and whether or not it could properly cover a surface. Students were asked to mix together two separate paint mixtures, one consisting of plaster of paris, water, and pigment, and the other consisting of flour, salt, water, and pigment. The plaster of paris mixture, though effective in creating a quick paint, represents an option that is still not totally environmentally conscious, but is still a good alternative to the store bought paints. Ideally, the most environmentally friendly (and entirely health conscious) paint would be the flour paint, for it consists solely of foodstuffs and pigment and would biodegrade easily. You could even feed it to your kids and they would be no worse for wear. After mixing the paints together, students were asked to apply one coat of the mixtures to a prepared sheet of clear mylar, alongside the other paints. Then, using the LabView software, a small photovoltaic, and a flashlight, students conducted a series of three trials with each paint, shining the flashlight through the paint onto the photovoltaic to measure the light intensity. By the parameters of the experiment, whichever paint had the highest intensity would be the least legitimate paint, for it obviously does not easily cover the surface. Students were then asked to average their results and compare which paint is the most legitimate, while also considering why and how paints could be made more environmentally conscious without losing their appeal and ability.

Our procedure :

we asked the students running our experiment to mix two homemade paints

Chalk paint:

1 cup of powdered paint

2 and  a half tablespoons of plaster and 1/2 tablespoon of water

Flour paint:

1tbsp of water

1tbsp of flour

1tbsp of salt and about a tbsp. of powdered pigment

immediately our experimenters saw that the flour paint was a little bit gritty and thin while the plaster paint was thick and could easily clump up.

our second group of experimenters did a great job in this mixing process and when they painted the two homemade paints on the Mylar they came out opaque, which you can see in the photo below.

this success from the experiment group really drove home our ideas that homemade paint can actually be used similarly to the store bought alternatives to decrease waist that impacts the environment.

After the fun part of mixing paints together and applying them to the Mylar our groups used an led flashlight and a photovoltaic that looked like this:

by putting the paint colored Mylar over the photovoltaic and shining our LED light through it we could record for ten seconds the amount of light and therefore opacity and quality of the paint. we had our experimenters run each type of paints three times for ten seconds each. for each paint type we had the experiments average the three trial data points together so we could have a quantitative number to tell us the opacity of the paint.

This is a data sheet from one of the two groups that ran our experiment. You can see that their averages for each type of paint are

Oil -0.6

Acrylic 0.12

Chalk 0.27

Flour 0.34

As you can see from the data that the out of the tube oil and acrylics let less light through the Mylar and are more opaque. This means in the use of the paint they cover better and are more useful when painting. This outcome is what we expected, the companies that makes these paints anticipate the transparency of the pigment and make them so they can withstand light shining through. You can also see the chalk being thicker in the mixing of the paint convers better than the flour which was thin and let through the most amount of light. The practical problems with the chalk paint is that plaster if too thick in the mixing process can flake off and crumble, so although it convers better you can easily have it flake off when using it at home.

                We think that our experiment overall was pretty successful too. Despite the fact that we did not choose a very scientific base to start from, I think that we were able to come up with something scientific in the end. While observing people doing the experiments during the final, I could see that a lot of people liked what they were doing even if it wasn’t directly related to science. It was familiar since we had already done a lab very similar to this and it was also hands on, allowing them to use what they made in the lab. Making something is away fun, even if it was a bit messy. I think that it taught the students a lot about how to make alternative to paint, even if some of them didn’t work so well and needed multiple coats. However I do not think that our approach was perfect. It was still very art related and thinking back on it the addition of the photovoltaic lenses seemed a little bit tacked on; it was like we were trying to make the lab less about the paint and more about data you could collect. Maybe if we thought about it more and had a bit more time we could have come up with something that was very quantitative.