T.S. Bailey, J.G. Luther, A.J. Gebhardt, R.D. Duquette, K.D. Denef
Gelastomerics LLC | Colorado State University,
United States
Keywords: thermoplastic elastomer, hydrogel, surface lubricity, poroelasticity, soft-tissue mimics
Summary:
Technological advancement across the medical device and healthcare sectors increasingly depends on the innovative use of thermoplastic elastomers (TPEs), which provide tunable hardness, flexibility, toughness, and resistance to fatigue and fracture under cyclic loading. Yet, many device applications also demand that elastomeric surfaces remain lubricious, low-friction, and biologically inert to ensure safe and sustained contact with soft-tissues and biological fluids. Minimally invasive catheter-based diagnostic and interventional systems used to surgically access increasingly remote cardiovascular and neurovascular spaces represent particularly important examples. Concurrently, the healthcare industry faces a growing demand for scalable hydrogel technologies that accurately reproduce the biomechanical properties of hydrated soft tissues—such as poroelasticity, rapid recovery, and intrinsic lubricity—while maintaining strength and durability. Hydrogel materials proposed for soft-tissue repair and replacement, due to say degenerative loss of function in the meniscus of the knee, intervertebral discs of the spine, or mitral and aortic valves of the heart, must exhibit mechanical resilience comparable to TPEs to withstand the dynamic stresses associated with long-term implantation. However, existing hydrogels fail to meet these standards due to their inherently low polymer chain density when hydrated and their susceptibility to degradation in biological environments. In our view, these two challenges converge on a single problem: an inability to effectively integrate elastomer-like durability with hydrogel-like lubricity and poroelasticity. In this presentation, we present Gelastomerics LLC’s simple but elegant solution, designed to address the critical absence of such materials in the medical device design toolbox. This solution, born out of the research labs at Colorado State University, is based on a thermoplastic composite approach free from complex chemistries and non-standard processing requirements, with the intention of generating a scalable material platform capable of spanning the entire hydrogel to elastomer performance spectrum. Here we use a combination of melt-state processing and self-assembly to produce a series hydrogel elastomers with tensile moduli, ultimate strengths, bulk toughnesses, elongations, and fracture energies comparable with industrial elastomers, while maintaining water contents in the 40 to 90 wt% range and surface lubricities (COFs) comparable with pure hydrogel materials.