Senior Materials Engineer, Polymer Additive Manufacturing

Elastium is an advanced manufacturing startup company transforming the legacy footwear industry toward rapid, fully automated, and localized production. Our manufacturing platform combines proprietary hardware, software, and materials science to make shoe production as effortless as pushing a button. We're building the most frictionless way of turning bits into useful atoms, sending ripples of singularity across the industry, and bringing tens of billions of GDP back to America.

Our bet is simple: the future of manufacturing belongs to companies that can program matter as fast as software. We are looking for a Senior Materials Engineer to own the actual atoms to be programmed. This is a hands-on frontier engineering role spanning polymer chemistry, compounding, characterization, process development, and production validation. Specifically, you will:

• Lead the full cycle development of new foam compounds across TPU, PEBA/PEBU, and adjacent systems.
• Design formulations, run material production trials, test materials in our production cells, build process windows for foaming, deposition, and bonding inside the production cells.
• Develop advanced additive manufacturing processes for low-density thermoplastic elastomer foams.
• Own material characterization workflows, including rheology, thermal analysis (DSC, TGA), density, morphology, degradation and stability, and mechanical testing (tensile/compression, energy return, hysteresis, and durability metrics)
• Source and evaluate raw materials, additives, blowing agents, and processing aids.
• Work hands-on with compounding lines and external/internal production setups to optimize throughput, consistency, and foam quality.
• Oversee material manufacturing and scale-up, from experimental batches to robust repeatable production.

• BS or MS in Materials Science, Polymer Chemistry, Plastics Engineering, Mechanical Engineering, or equivalent.
• A minimum of 3 years of industry experience focusing on the applications of polymers in product development, including proven experience developing new polymer formulations or processes.
• Deep understanding of physics governing in-process and post-process polymer behavior: thermodynamics, mechanics of extrusion/deposition, polymer rheology, crystallization/viscoelasticity, etc.
• Strong analytical and problem-solving skills, with the ability to apply engineering principles to novel applications and to troubleshoot materials-related challenges in design and production settings.
• Familiarity with mechanical testing, data-driven process development and statistical process control.
• Experience with polymer additive manufacturing.
• You're high-agency operator with mission-critical discipline and accountability. You identify and neutralize threats before they escalate.

Why this job matters

At Elastium, you won’t be another engineer optimizing inside an existing box—you’ll build in the wild, architecting a new industrial era where factories run like software, starting with footwear. Footwear is an enormous challenge because it’s a massive, messy, labor-heavy industry that left the U.S. for a reason. Reinventing how footwear is made at scale requires breakthrough materials science that can survive the brutal realities of production, scale across thousands of autonomous robotic cells, and deliver world-class product quality. If you want to solve problems that fundamentally reshape the physical world, this is the mission.