C.M. Leibig
Chromatic 3D Materials Inc.,
United States
Keywords: 3D printing, additive manufacturing, elastomers, multi-material, polyurethane
Summary:
Additive manufacturing continues to redefine design and production possibilities for the medical device industry, yet material properties can limit its utility. Most 3D printing platforms rely on thermoplastic polymers, which often fall short when applications require long-term durability, elasticity, and environmental resistance in physiological conditions. This presentation introduces RX-AM, a reactive extrusion additive manufacturing technology developed by Chromatic 3D Materials, which overcomes these limitations by enabling the direct deposition and crosslinking of thermoset polyurethane elastomers. RX-AM employs a reactive liquid-feed process in which polymer precursors are combined and chemically crosslinked within seconds of deposition. In contrast to conventional thermal fusion seen in thermoplastic-based methods, RX-AM forms covalent bonds across and between deposited materials. This capability allows multiple formulations, each with distinct chemical and mechanical characteristics, to be integrated within a single build. The result is a chemically continuous, meso-structured architecture with robust interfacial bonding and tunable local properties. These meso-structured materials exhibit a combination of flexibility, resilience, and interlayer cohesion not achievable in traditional layer-by-layer printing or with casting processes. A focus of the presentation will be the mechanical behavior of RX-AM meso-structured printed structures. Experimental characterization has shown that these films can display finely graduated stiffness with improved tensile strength. The ability to engineer gradients in modulus and strain recovery within a single component enables functional transitions between rigid and soft regions, providing design opportunities previously unavailable for compliant medical devices. Additionally, the covalent linkages between domains mitigate common failure modes such as delamination or fatigue at material interfaces, ensuring long-term mechanical integrity under physiological stress conditions. By uniting reactive polymer chemistry with precision additive manufacturing, RX-AM represents a major advance for biomedical engineering. It offers the ability to design and produce durable, patient-specific elastomeric devices that meet stringent performance requirements while expanding the frontiers of material and structural design in medical technology.