AMP_04_May_June_2021_Digital_Edition

A D V A N C E D M A T E R I A L S & P R O C E S S E S | M A Y / J U N E 2 0 2 1 9 scales. Additionally, glasses are found to be more homogeneous than previ- ously thought. yale.edu . 3D-PRINTED THERMOPLASTICS Researchers from the Singapore University of Technology and Design’s Soft Fluidics Lab developed a simple method to 3D print thermoplastics using embedded media in freeform manners. Termed freeform polymer precipitation (FPP), the method uses microparticulate gels as surrounding media, simultaneously offering two es- sential functions—structural support and phase change induction of the printed ink via immersion precipitation. 3D printing based on immersion pre- cipitation with surrounding micropar- ticulate has unlocked the capability of freeform fabrication of thermoplastics. The work demonstrated the use of both water-based and ethanol-based microparticulate gels as surround- ing media that allowed the increased numbers of solvents and polymers to be used in FPP. Polymer inks with low polymer concentrations and inks with pore-inducing agents conferred internal porosity to the printed struc- tures. “FPP offers a unique way to fab- ricate mechanically strong components consisting of thermoplastics in various 3D shapes without support materials.” www.sutd.edu.sg . A polymer ink is printed by a direct ink writing 3D printer in Bingham plastic microparticulate gels as embedding media. The surrounding media supported the printed inks and caused in situ phase separation by immersion precipitation. Courtesy of SUTD.