Amino acid-derived phosphoramidate vinyl esters enable surface-eroding photopolymers for additive manufacturing with tunable mechanics.

Photocurable vinyl esters (VEs) are attractive alternatives to (meth)acrylates for biomedical applications due to their low cytotoxicity and biocompatible degradation products. However, their extreme brittleness and slow degradation under physiological conditions limit their use in load-bearing and drug-delivery applications. Here, we developed valine-derived phosphoramidate vinyl esters (Val-APdA-VEs) that combine tunable mechanical performance with controlled hydrolytic degradation. Copolymerization with divinyl adipate and multifunctional thiols produced photoreactive resins with adjustable network properties. Rapid photopolymerization yielded tough, highly crosslinked polymer networks with adjustable mechanical properties. Under physiological conditions, the materials exhibited steady mass loss, consistent with predominantly surface-controlled degradation. The resins were readily processed by digital light processing (DLP) and extrusion-based printing to produce complex 3D structures, and were additionally patterned by nanoimprint lithography (NIL) to generate microstructured surfaces. In vitro, the materials were non-cytotoxic to chondrocytes and supported strong cell attachment and viability. These results establish amino acid-derived phosphoramidate vinyl esters as a molecular design platform for biodegradable photocurable networks in which degradation behaviour and mechanical performance can be systematically tailored without compromising processability or cytocompatibility.