When most people think of 3D printing, they picture small plastic toys, figurines, or hobby projects made layer by layer. For Sijia Huang, a new assistant professor in the John and Marcia Price College of Engineering’s Department of Chemical Engineering, that limitation is exactly what motivates her work.
Huang’s research focuses on designing “multimaterials,” materials made from combinations of soft and hard components that work together as a single system. Inspired by biological structures like skin and bone, her lab develops new material systems that behave more like the human body and less like uniform plastic. Huang’s work points out that nature rarely uses just one material. “Our fingertips are soft, our bones are stiff and the transition between them is gradual,” Huang says. “That’s what gives us both strength and flexibility.”
Huang joined the Price Engineering faculty in 2025, launching the Multimaterial Lab with the goal of rethinking how materials are made for 3D printing. While current printers can produce complex shapes, the materials themselves are often limited to a single, uniform plastic. Huang’s work shifts the focus inward toward the internal structure of materials and how those structures determine performance at the human scale.
Her approach centers on polymer chemistry, the science behind plastics and flexible materials. Rather than printing separate materials and bonding them together, Huang’s lab designs chemical systems that can change properties, like softness or stiffness, based on how they are processed. Using light-based 3D printing techniques, the same liquid material can be cured differently in different regions, creating smooth gradients instead of sharp interfaces.
“When soft and hard materials are stuck directly together, they tend to break at the point where they meet. Natural materials avoid that by using gradual transitions,” Huang says.
The inspiration for this work began early in Huang’s career. As an undergraduate, she was introduced to polymer systems by her advisor, who showed her how versatile plastics could be. Later, an internship at The 3M Company exposed her to photopolymerization, using light to rapidly cure materials, which ultimately shaped her graduate research and current focus.
Beyond the chemistry itself, Huang is also tackling a major challenge in modern materials science: how to measure and understand materials efficiently. Because her lab’s materials can take on many different properties depending on how much light they receive, traditional one-by-one testing methods are too slow. To address this, her group is developing visualization and screening tools that allow researchers to quickly understand how materials behave in different regions as they are printed.
These advances have wide-ranging applications. Huang points to wearable devices, soft robotics and next-generation electronics as areas where multimaterials could reduce manufacturing steps and unlock new designs. Instead of assembling separate components, future devices could be printed in a single process, with materials tuned exactly where needed.
Huang’s lab is still growing, but collaboration is already a defining feature. She says her graduate students work closely together, often offering ideas across projects. Two students even followed her from a previous position at Lawrence Livermore National Laboratory, a testament to the mentorship culture she values.
Huang says the University of Utah was a natural fit. She was drawn by the collaborative environment within the Price College of Engineering and the department’s supportive culture. Outside the lab, Utah’s access to outdoor recreation sealed the deal. “I love climbing and snowboarding,” Huang says. “Being close to the mountains is a huge bonus.”
As Huang builds her research program at the U, she hopes her work will help redefine what materials and 3D printing can become.