MEAM Ph.D. Thesis Defense: “Mechanical Robust Biocompatible Polymeric Networks for Repetitive Loading”

Crosslinked biocompatible polymer networks offer unique potential for biomedical applications that demand high resilience under repetitive load-bearing conditions. However, conventional hydrogels often exhibit poor mechanical strength and irreversible damage under cyclic deformation. To address these challenges, this work presents a class of engineered polymer network designed for enhanced mechanical robustness: cryogel-based double-network (DN) hydrogels.

In this system, collagen cryogels were formed through glutaraldehyde (GA) crosslinking, producing hyperelastic and macroporous scaffolds with shape-memory behavior. These cryogels served as the first network of DN hydrogels, further reinforced by an ionically crosslinked alginate network. Mechanical testing, including uniaxial compression, cyclic loading, and hyperelastic modeling, revealed excellent mechanical resilience (recovery after 90% compression), compressive modulus tunability (10-200 kPa), and peak stresses among 0.2~15 MPa. These hydrogels also demonstrated cytocompatibility, making them suitable for dynamic applications in soft robotics, tissue engineering, and mechanobiology research.

Together, these findings establish a framework for designing polymer networks that balance biocompatibility, resilience, and functionality under repetitive loading situation. The DN hydrogel systems exhibit reversible deformation, offering new opportunities for load-bearing tissue regeneration, minimally invasive implants, and wearable devices. By combining network architecture with functional chemistry, this research advances the next generation of durable, adaptive biomaterials for clinical and translational use.