In early February 2020, a group of Materials Science and Engineering seniors working on their capstone project faced some real-world problems. Flooding due to a burst pipe limited their access to the labs in the Engineering Centers and Materials Science and Engineering buildings; some group members got sick; all had to balance their other courses with the demands of the project.
The students had to motivate themselves to adapt, find new solutions to their problems, and try to keep the project moving along no matter what occurred. It’s different from traditional coursework, where each equation has a definite solution. “All our engineering problems have had answers so far, till this,” says Natalie Stewart, who along with MS&E seniors Lindsay Friedman, Manthra Venkatakrishnan, Amy Lossen and Teressa Baumann, came together in fall 2020 for their two-semester capstone project.
Lindsay Friedman performs a UV-Vis test on a sample from the group’s first trial.
In particular, the team is working with Neenah, Wisconsin-based Amcor, a major plastics packaging manufacturer which creates products like coffee bags, meat & dairy packaging, rigid water bottles, and hundreds of others. The goal of their project, “The impact of modified high-density polyethylene (HDPE) on customer critical-to-quality (CTQs) metrics,” is to modify a blown film to make existing products more recycle-stream compatible, part of Amcor’s push to make product offerings reusable or recyclable by 2025.
Specifically, with the guidance of Kevin Nelson and Megan Goodrich at the company, the team is trying to figure out a way to move pigment from the outer layer of a film, which prevents it from being recycled, to a thinner inner layer. That swap would allow more of the packaging to be reused.
But moving the pigment is not so simple. The plastic needs to retain the same opacity, formability and mechanical properties, and pigments often change these characteristics. That’s why the students are testing various types of pigments and additives.
After a semester of planning and benchtop testing, the team brought its findings to the Amcor factory in January 2020 for the first round of large-scale testing and performed a second round of tests in early March.
While the team is gaining plenty of hands-on technical skill from the capstone project, Baumann, who has a job lined up with Amcor after graduation, says the other skills the team members are developing are equally valuable. “The long-term project planning experience is important because that’s a lot of what engineers do in the field and in manufacturing specifically,” she says. “They work on different projects like this one and follow them through to their completion.”
Amy Lossen, who will pursue a graduate degree in Mechanical Engineering at UW-Madison, agrees that learning to work as a team has been one of the best lessons. “Coming into it, we were all friends and knew we were all hard workers. But there’s still a learning curve when working with people for this long,” she says. “We each have our own style and methods of getting stuff done. So, figuring out the best place for each person and where everyone can, not only learn and pick up new skills, but also be as productive as possible has been really beneficial.”
Venkatakrishnan, who will be working for the Kimberly-Clark Corporation after graduation, says the capstone project is very important for Materials Science majors because it ties together years of coursework that is broad and often theoretical. “Because we don’t have as much design experience as other engineering majors, it’s kind of hard to see how one piece fits into the other,” she says. “For example, how does material transport play into this? How does thermodynamic principles affect what we’re doing? The capstone project pulls it all together and is a completion of what we’re learning.”
Chances are, when the students present their final findings at the end of the semester, the Amcor capstone team won’t have completely ironed out the film pigment problem, though hopefully they will have made some good progress. But that’s not really the point. “Our clients at Amcor are great,” says Baumann. “It’s not as much about completing the project for them. They care about our knowledge and what we’re learning. There are going to be a lot of us who go into industry and this is a good experience to get exposed to that and see what we’re going to do in our future careers.”