3D Printing in Stimuli-Responsive Yield-Stress Fluid with an Interactive Dual Microstructure

November 22, 2022
Schematic representation of sectioned 3D printing of a complex object. At 4 °C the bath is a low viscosity fluid consisting of nanoclay platelets coated with Pluronic F127 (PEO-PPO-PEO triblock copolymer). At 25 °C micellization results in a bath with high yield-stress. The shear thinning behavior of the bath allows smooth movement of the printing nozzle while supporting the printed materials when the nozzle-induced shear stress dissipates, and the bath resolidifies.

Scientific Achievement

It was shown that 2% Laponite nanoclay and 30% Pluronic F127 form an interacting dual microstructure in aqueous solution, with high yield stress of 554.2 Pa at 25 °C, and low viscosity approximately 1 Pascal-second at 4 °C.

Significance and Impact

This work shows how technical limitations of support bath assisted 3D printing can be overcome via temperature cycling of dual microstructure nanocomposite systems.

Research Details

  • Structures of dispersed Pluronic-coated Laponite at 4 °C and Laponite house-of-cards assembly embedded in Pluronic micelles colloidal crystal at 25 °C were determined by small-angle neutron scattering (SANS).
  • Additional properties were determined by measurements of dynamic shear-stress, viscosity, differential scanning calorimetry and electron microscopy.
  • Viability of the system was demonstrated by 3D printing of various artifacts.

“Three-Dimensional Printing in Stimuli-Responsive Yield-Stress Fluid with an Interactive Dual Microstructure”
Weijian Hua, Kellen Mitchell, Lasith S. Kariyawasam, Changwoo Do, Jihua Chen, Lily Raymond, Naima Valentin, Ryan Coulter, Ying Yang, and Yifei Jin
ACS Applied Materials & Interfaces 14, 39420 (2022). DOI: https://doi.org/10.1021/acsami.2c12465