Mechanical Studies of Bovine Serum Albumin-based Bioplastics in Additive Manufacturing

Abstract

Additive manufacturing (AM), or 3D printing, has revolutionized material fabrication by enabling customization, low-cost prototyping, and high efficiency. Vat photopolymerization, a widely used AM technique, uses light to selectively cure resins, offering high resolution and fast printing speed. However, most commercial resins are petroleum-based, exhibiting low biocompatibility and degradability, which limits their use in biomedical sustainability applications. This study investigates the mechanical properties of bovine serum albumin (BSA)-based bioplastics and methods to enhance the mechanical performance of BSA-based bioplastics. BSA-based bioplastics offer tunable mechanical properties that are comparable to commercial products. A dataset of 152 commercial resins from eight leading 3D printing companies was analyzed to create Ashby plots — in many cases, BSA-based bioplastics outperformed commercial resins in both strength and ductility while offering greater biodegradability. To further enhance the mechanical performance of these bioplastics, tannic acid (TA) and heat treatments were applied to methacrylated BSA (MA-BSA) materials. Swelling in TA followed by a denaturing thermal cure on printed structure was found to enhance the non-covalent bonding within the network and reduce rehydration, which increased Young’s modulus from 389 MPa to 757 MPa and improved ultimate tensile strength fivefold. With additional solvent exchange with ethanol, the Young’s modulus of MA-BSA bioplastics rose to 1.3 GPa, which made it comparable to those commercial bio-based resins. These advancements showcase BSA-based bioplastics as a promising, sustainable alternative for future biomedical 3D printing applications.