Team:Stanford-Brown/Plastic
Plastic Folding
Testing and Applications
Why plastics?
Plastic is an extremely versatile material that can be used in a multitude of applications such as in medical devices, construction, prototyping, and much more. Currently, many common plastics require the use of petrochemicals to manufacture. To utilize the benefits and versatility of plastics in long term space travel and space colonies would require the importation of petrochemicals into space. With the limited volume and mass payloads of space travel, our team wanted to try to find an alternative to shipping petrochemicals into space.
Our team looked to synthetic biology to find a solution to the manufacture of plastics in space to minimize the use of petrochemicals. This summer we wanted to engineer the bacteria E. Coli to produce two kinds of plastic: Polystyrene and P(3HB). The prospect of being able to send a sample of bacteria into a space station or colony and having that bacteria manufacture plastic is an exciting prospect for our team.
How does plastic fold?
Most plastics are long organic polymers with a high molecular weight. When these long chains of monomers are prestretched in their manufacturing they have a high level of organization. When heated to their glass transition point, these prestretched plastics will contract in the dimention that they were prestrech. With the use of pigments (in our case, biopigments) we can select where and how the prestretched plastic contracts. By drawing on these pigments on the plastic and using infrared light from the sun, we can make the plastic fold. This is because in a flat sheet of prestretched plastic, drawing a dark line on the plastic will allow that section of the plastic to heat up and contract faster than the rest of the plastic. Having the dark line only on one side of the plastic will cause the plastic to fold toward that side as seen in figure 1