Improved resolution of 3D printed scaffolds by shrinking

Area of Science:

• Biomaterials Engineering
• Additive Manufacturing
• Materials Science

Background:

• Three-dimensional printing (3DP) is a layer-by-layer fabrication technique for creating 3D objects.
• Current 3DP methods for biomedical applications have limitations in print resolution.
• Enhancing scaffold resolution is crucial for precise tissue engineering and regenerative medicine.

Purpose of the Study:

• To develop and evaluate a materials processing strategy for enhancing 3DP resolution.
• To investigate the effects of polymer content and post-processing on scaffold properties.
• To demonstrate the predictability and utility of the shrinkage strategy for complex 3D components.

Main Methods:

• Fabrication of porogen preforms using 3DP.
• Infusion of preforms with polymer solutions (e.g., polyethylene glycol diacrylate - PEG-DA).
• Controlled leaching of porogen and polymer shrinkage via drying, followed by heat treatment for dimension retention.

Main Results:

• Reduced polymer content led to increased scaffold shrinkage, with up to ~80% volume reduction at 20% PEG-DA.
• Secondary heat treatment successfully preserved scaffold microarchitecture and dimensions, even in aqueous environments.
• Demonstrated predictable shrinkage by successfully fitting 3D components with interlocking features.

Conclusions:

• The described material processing strategy offers a viable method to enhance the resolution of 3D printed scaffolds.
• This approach is applicable to a wide range of polymers, independent of binder-powder interactions.
• The technique provides an alternative to optimizing printing physics for improved feature definition in 3D scaffolds.