Development of a nano-filled composite experiment for a freshman class
Projects that help first-year engineering and science students become more familiar with concepts of nanomaterials may become an important vehicle for increasing student interest and understanding of the potential of technologies that manipulate materials at the molecular level. The authors received a National Science Foundation NUE award entitled "Infusing Nanomaterials into Undergraduate Science and Engineering Curricula" for the development of an undergraduate Certificate in Nanomaterials within the colleges of engineering and science. As part of the NSF-supported project, but separate from the certificate program, we are developing a series of experiments that will be introduced in the first-year engineering program at a large, research-intensive university. The goal of the experiments is to help students determine how differences in concentrations of nano-sized particles, which are added to common materials, can change physical properties. In this exercise, student teams will fabricate composite films filled with different concentrations of carbon black in two different types of polymers: 1. latex-based composite with poly (vinyl acetate), and 2. solution-based composite with poly (vinylpyrrolidone). The concentrations vary from about 2 wt% to 15 wt%. For mechanical properties, the students will determine the tensile strength and the strain to failure using an Instron test machine with a 1000 lb f load cell. For electrical properties, the students will determine the electrical resistivity for the different carbon black concentrations. Preliminary experiments show relatively little change in the tensile strength. However, there is a three to five order change in the composite's resistivity. A select group of freshman will run the experiment during spring 2007. Students will be asked to propose hypotheses to explain why changes in the concentrations change or fail to change physical properties of the materials. © American Society for Engineering Education, 2007.
author list (cited authors)
Griffin, R., Karaman, I., Ji, M., Grulan, J., & Froyd, J.