Ultrasound-Enabled Advanced Manufacturing of Polymers

Ishan Joshipura | 21-FS-032

Project Overview

The purpose of this feasibility study was to evaluate whether standing waves of ultrasound could make thin films of polymers in a continuous or additive fashion. A secondary goal was to explore whether this approach could be utilized with additive manufacturing (AM) techniques or form polymer microencapsulations. To test this approach, we built custom resin baths affixed with ultrasound transducers. We varied the geometry to focus the ultrasound spatially over a range of ultrasound frequencies. In addition, we utilized COMSOL multiphysics software to model the pressure within custom baths. These models were utilized to determine optimal operating conditions to induce cavitation. Our results showed that high-power input and spatially focused ultrasound is necessary to induce polymerization. This approach could be implemented into AM techniques to incorporate fillers and solid additives in polymer composites, alter flow properties of inks, and improve curing and processing of printed parts. In addition, we were able to form microencapsulation of polymers with metal additives in a rapid and facile manner. Nevertheless, more work is needed to optimize polymerization conditions to produce parts in a rapid manner that would be complimentary or competitive with state-of-art AM techniques.

Mission Impact

This project supports Lawrence Livermore National Laboratory's core competency in Advanced Materials and Manufacturing. The development of an ultrasound-based polymer additive manufacturing capability would support the NNSA/DOE mission to develop science and technology tools and capabilities to meet future national security challenges. These technologies can enable NNSA to create new ways of responding to national security challenges. These polymeric techniques or produced parts may be useful for emerging security challenges associated with technology surprise in space, cyberspace, bioscience, bioengineering, and other military domains.

Publications, Presentations, and Patents

IL-1370601: Joshipura, Ishan, et al., Ultrasound-induced additive manufacturing of polymers and composites, U.S. Patent 16336-000193-US, filed.