Lithographic crystallinity regulation in additive fabrication of thermoplastics (CRAFT)
- Alex J. Commisso
- Eric M. Nagel
- Meghan T. Kiker
- Elizabeth A. Recker
- Adam Bischoff
- Michael J. Holzmann
- Hayden E. Fowler
- Minh Nhat Pham
- Chi Phuong H. Nguyen
- Esteban Baca
- Hernán Villanueva
- Nirvana T. Almada
- Keldy S. Mason
- Claire Jolowsky
- Guddi Suman
- Keith J. Fritzsching
- Bryan Kaehr
- Johanna J. Schwartz
- Leah N. Appelhans
- Brad H. Jones
- Caitlin S. Sample
- Devin J. Roach
- Zachariah A. Page
- Samuel C. Leguizamon
2026-01-29
For semicrystalline polyolefin thermoplastics, the balance between interconnected ordered crystalline and disordered amorphous regions is paramount to their performance and processability. However, contemporary manufacturing strategies, from injection molding to three-dimensional (3D) printing, result in monolithic objects, unable to spatially encode crystallinity. We develop a light-based approach for fabricating mechanically robust polyolefin thermoplastics with microscopic control over crystallinity in 3D space. Light dosage governs polymer stereochemistry giving access to a continuum of materials, from strong rigid plastics, such as high-density polyethylene, to more extensible materials akin to low-density polyethylene, all at the flick of a switch. Leveraging this finding in lithographic grayscale 3D printing enables rapid multimaterial fabrication with voxel-level control over optical and mechanical properties, opening avenues in information storage, soft robotics, and energy damping.