A holistic model for melt electrowritten three-dimensional structured materials based on residual charge.

Area of Science:

• Materials Science
• Polymer Science
• Additive Manufacturing

Background:

• Polymer melt electrowriting (PME) is crucial for fabricating complex structures.
• Printing accuracy in PME is limited by residual charge accumulation in fibers.
• This charge effect is particularly problematic in 3D scaffolds and multilayered materials.

Purpose of the Study:

• To develop an analytical model to understand the impact of residual charge on PME accuracy.
• To investigate the relationship between charge distribution and fiber morphology.
• To provide a systematic approach for enhancing printing precision.

Main Methods:

• An analytical charge-based model was developed to calculate jet segment electric potential energy.
• The model considers residual charge amount and distribution in the jet and deposited fibers.
• Key parameters influencing evolution modes were analyzed through global, local, and polarization charge effects.
• Lateral characteristic curves and surfaces were used to analyze fiber morphology and charge interplay.

Main Results:

• The model identified distinct modes of energy surface evolution based on charge distribution.
• Three charge effects (global, local, polarization) were defined to explain parameter influence.
• The model successfully explained phenomena like 'fiber bridging' in parallel fiber printing.
• Investigated the impact of lateral location and grid number on fiber morphology.

Conclusions:

• The study provides a comprehensive understanding of the interplay between residual charge and fiber morphology in PME.
• The developed model and analysis framework offer a systematic workflow to improve printing accuracy.
• This research is vital for advancing the fabrication of high-precision 3D polymer structures.