Thermal Post-Processing of 3D-Printed Poly(glycerol dodecanedioate) Controls Mechanics and Shape Memory Properties

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Medical Device Engineering

Background:

• Patient preference for minimally invasive procedures (MIS) drives demand for advanced medical devices.
• Shape memory polymers (SMPs) are promising for MIS device development due to their unique properties.
• Acrylated poly-(glycerol-dodecanedioate) (APGD) is a biodegradable SMP suitable for MIS applications.

Purpose of the Study:

• To investigate the impact of thermal post-processing on 3D printed APGD.
• To determine if thermal post-processing can mitigate property differences arising from different 3D printing methods (material extrusion vs. vat photopolymerization).
• To optimize APGD properties for biomedical applications through tailored post-processing.

Main Methods:

• 3D printing of APGD using material extrusion (ME) and vat photopolymerization (VP) modalities.
• Characterization of physical, mechanical, and shape memory properties of freshly fabricated and thermally post-processed APGD samples.
• Analysis of melt transition temperature (Tm), relative crystallinity, gel content, shape recovery (Rr), and Neo-Hookean parameter (C1).

Main Results:

• Differences in Tm, crystallinity, gel content, Rr, and C1 between ME and VP printed APGD were observed.
• 24 hours of thermal post-processing significantly reduced these property variations.
• Post-processing effectively harmonized the properties of APGD regardless of the initial printing modality.

Conclusions:

• Thermal post-processing is a critical step to control and standardize the properties of 3D printed SMPs like APGD.
• Tailoring post-processing to the manufacturing method is essential for optimizing thermal, mechanical, and shape memory characteristics.
• This approach enhances the potential of 3D printed SMPs for developing next-generation medical devices for MIS.