Multiaxial Expansion of 4D-Printed Shape Memory Polymer Scaffolds via Programming via Printing (PvP)
Date of Award
8-22-2025
Date Published
September 2025
Degree Type
Thesis
Degree Name
Master of Science (MS)
Department
Biomedical and Chemical Engineering
Advisor(s)
James Henderson
Abstract
Shape memory polymers (SMPs) offer unique opportunities for engineering responsive medical devices that can adapt to changing anatomical environments. However, most SMP-based systems are limited to uniaxial deformation which restricts their ability to conform to complex geometries found in soft tissue applications. Moreover, 3D approaches to print and program SMPs have demonstrated printed parts that can contract, but printed parts that can expand after printing has not been demonstrated to date. This work presents the design, fabrication, and evaluation of a 4D-printed SMP scaffold capable of controlled expansion along all three orthogonal axes (x, y, and z). Utilizing a method known as Programming via Printing (PvP), directional tensile strain was embedded directly during extrusion by tuning print parameters such as infill direction, speed, and orientation. The scaffold was composed of several elements to help drive expansion of the whole structure—bowtie-framed beams for x-axis expansion, a flat triangular element for y-axis unfolding, and an upright triangular element for z-axis elevation. Each element was individually optimized for actuation performance. MM-3520 thermoplastic polyurethane was used to fabricate custom filament, and scaffold components were printed using fused deposition modeling (FDM). Functional testing involved thermal activation in a 70 ± 5 °C water bath and quantified expansion using digital calipers and image J analysis. Results confirmed reliable multiaxial shape recovery, with measurable deformation in each axis corresponding to the programmed strain. This study highlights the ability of Programming via Printing (PvP) to enable multiaxial shape change within a single, continuous fabrication process which eliminats the need for postprocessing or external mechanical programming. By achieving controlled expansion in the x-, y-, and z-directions, this work represents a significant advancement in the design of adaptive shape memory polymer devices. The demonstrated approach offers a scalable pathway for engineering patient-specific, shape-morphing scaffolds suited for regenerative medicine, airway stabilization, and anatomically complex tissue reconstruction
Access
Open Access
Recommended Citation
Hendricks, Verona, "Multiaxial Expansion of 4D-Printed Shape Memory Polymer Scaffolds via Programming via Printing (PvP)" (2025). Theses - ALL. 985.
https://surface.syr.edu/thesis/985
