Morphing materials take shape at Rice University

Rafael Verduzco and graduate student Morgan Barnes of Rice University's Brown School of Engineering in Texas developed a method to print objects that can be manipulated to take on alternate forms when exposed to changes in temperature, electric current or stress.

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According to Rice, the researchers think of this as reactive 4D printing and their findings are published in ACS Applied Materials and Interfaces.

In 2018 the team reported their ability to make morphing structures in a mould but using the same chemistry for 3D printing limited structures to shapes that sat in the same plane. Consequently, no bumps or other complex curvatures could be programmed as the alternate shape.

Overcoming that limitation to decouple the printing process from shaping is a significant step toward more useful materials.

"These materials, once fabricated, will change shape autonomously," Verduzco said in a statement. "We needed a method to control and define this shape change. Our simple idea was to use multiple reactions in sequence to print the material and then dictate how it would change shape. Rather than trying to do this all in one step, our approach gives more flexibility in controlling the initial and final shapes and also allows us to print complex structures."