Solvent-cast 3D Printing of Biodegradable Polymer Scaffolds
John Tolbert, Diana Hammerstone, Nathaniel Yuchimiuk, Jonathan Seppala, Lesley Chow
Three-dimensional (3D) printing is a popular technique to fabricate scaffolds for tissue engineering because of its ability to produce complex tissue-like architectures. Scaffolds are often 3D printed using biodegradable polymers like poly(caprolactone) (PCL), poly(lactic acid) (PLA), and poly(lactic-co-glycolic acid) (PLGA) that can degrade to permit new tissue formation and have relatively low processing temperatures suitable for melt-based extrusion. However, melt-based techniques require temperatures and pressures high enough to achieve continuous flow, which limits the type of polymer and minimum feature size that can be printed. Solvent-cast printing (SCP) offers an alternative approach to print a wider range of polymers and increase resolution. For SCP, polymers are dissolved in a volatile solvent, which evaporates during deposition to leave behind a solid polymer filament. SCP therefore requires optimization of the polymer concentration in the ink in addition to print pressure and print speed to achieve desired print fidelity. Here, we investigated how each parameter influences print fidelity using PCL, PLA, and PLGA inks. We used capillary flow analysis to determine how print pressure affected the process-apparent viscosity and compared these results to ink viscosity measured using rheology. We found that rheology can be used to link a specific ink viscosity to a predicted set of print pressure and print speed for all three polymers. These results demonstrate how this approach can be used to accelerate optimization by reducing the number of possible combinations of polymer concentration, print pressure, and print speed. This strategy can be applied to other polymers to expand the library of polymers that can be printed using SCP.
, Hammerstone, D.
, Yuchimiuk, N.
, Seppala, J.
and Chow, L.
Solvent-cast 3D Printing of Biodegradable Polymer Scaffolds, Macromolecular Materials and Engineering, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932461
(Accessed May 23, 2022)