Additive Assembly for PolyJet-Based Multi-Material 3D Printed Microfluidics

PolyJet-based additive manufacturing (or “three-dimensional (3D) printing”) techniques allow for micro-to-mesoscale fluidic systems to be produced with multiple, fully integrated materials and unparalleled geometric versatility (due to the use of sacrificial support materials). Although the PolyJet 3D printing process is autonomous and fast, the post-processing methods required to remove the sacrificial materials can be exceedingly time-intensive for systems with enclosed channels, often resulting in device degradation. To bypass such issues, here we present a novel “additive assembly” strategy for realizing PolyJet-printed multi-material microfluidic components. In this work, we print a microfluidic capacitor as two separate halves to enable facile support material removal, and then fasten the parts together via designed integration features. Fabrication results revealed a significant reduction in post-processing time by approximately 98% compared to enclosed control designs. Experimental results for burst-pressure testing- a measure of component integrity- revealed that the additively assembled microfluidic capacitors retained a maximum internal pressure in excess of 189 kPa before failure. The results suggest that the presented additive assembly strategy holds promise for greatly extending the utility of PolyJet 3D printing for micro- and millifluidic applications.