Material science can be used to enrich secondary school curriculum and illuminate for students the connection between science and technology. Based on materials research being conducted at the University of Illinois, we have developed an interdisciplinary activity that integrates engineering with chemistry and material science.
Students investigate the behaviors of polymers by creating 3-dimensional (3-D) objects. Students can design objects that they “print” on the order of a cubic inch in about 20 minutes. The process students use to create these objects shows the application of engineering to material science in a novel and engaging way.
A photoactive chemical is initiated by the UV and blue light emitted from a data projector. This causes the formation of free radicals, which interact with molecules of a monomer and cause a polymerization reaction. The visual result of this reaction is that a liquid solidifies where students shine light. With black-and-white images, a data projector can direct the light to form any shape. This process can be easily modified to create true 3-D objects by adding another layer of the liquid to the top of the object and then shining the light again. With about 20 dollars worth of supplies from a hardware store, a simple staging device can be created to greatly simplify the process to create a 3-D printer in the classroom. Fabrication of this device can be done by students because the projector controls the x and y array of pixels; the object only needs to move in the z direction, unlike traditional rapid prototyping machines which control movement in the x, y, and z directions.
Results of integration into high school and college curriculum are discussed, and methods of integration and student perceptions of the activity are reported.