Introduction
Medical device development is full of materials compromises that shouldn’t have to exist. A tubing material that’s chemically compliant but too slippery to bond. A component strong enough for its intended use but not for the assembly process that gets it there. A proven polymer that works well in one anatomy but is too rigid for the next-generation device pushing further into complex anatomy. These are not edge cases — they are the everyday reality of minimally invasive device development.
Confluent’s FilmCast Select™ program was built to address exactly this gap. Rather than asking OEM customers to accept a standard formulation and work around its limitations, FilmCast Select™ lets customers intentionally select the performance attributes their application actually requires — across both PTFE and polyimide platforms — from the earliest stages of development. This case study shows how that approach played out across three distinct real-world challenges.
You Will Learn
- What FilmCast technology is, how it works, and why its layered construction produces uniquely controllable tubing properties
- How the FilmCast Select™ program structures the material selection process for OEM development teams
- How two customers needed REACH-compliant polyimide tubing — and why they needed completely different formulations to get there
- How a braided composite shaft buckling problem under compressive load was resolved without compromising other performance characteristics
- What Ultra Polyimide delivers compared to standard polyimide, and when it becomes the right choice
- How virtual performance modeling is used to evaluate braid reinforcement changes before physical samples are made
- Why PTFE’s traditional advantages are no longer sufficient for next-generation minimally invasive devices
- What distinguishes FlexaCast, DuraCast, and UltraCast PTFE from each other and from conventional ram extruded PTFE
- How the FilmCast Select™ process moves from performance attribute selection through material platform choice to design optimization
- What over 300 years of combined team experience means in practical terms for navigating regulatory and engineering tradeoffs
Strategic Insight: Material Selection Is a Development Decision, Not a Procurement Decision
The Compliance Challenge That Split Into Two Solutions
Two separate customers came to Confluent with the same regulatory requirement — REACH-compliant polyimide tubing for products sold in the EU. The requirement was identical. The devices were not. One needed optical clarity and easy adhesive cleanup after assembly. The other needed improved grip and stronger bonding capability during processing. A single compliant formulation would have served neither application well. FilmCast Select™ resolved this by offering two distinct REACH-compliant formulations — one glossy, one matte — each matched to the specific assembly and performance demands of the individual device. Compliance was achieved without asking either customer to compromise on what their application actually needed.
Structural Failure Mid-Assembly Is a Materials Problem Worth Solving at the Source
When a braided composite shaft begins to buckle under compressive load during a downstream assembly step, the instinct is often to add wall thickness or switch to a stiffer material. Neither answer is clean when other performance characteristics must be preserved. Confluent approached this challenge by presenting two genuinely different solution paths — a proprietary Ultra Polyimide formulation delivering roughly twice the tensile strength of standard material, and a braid reinforcement optimization validated through virtual performance modeling before any physical samples were made. Both options resolved the buckling. The customer chose based on where their biocompatibility testing already stood, not because one option was technically inferior. That is what a well-structured materials partnership looks like.
Standard PTFE Has Reached the Limits of What Next-Generation Devices Need
PTFE’s low friction and chemical inertness made it a natural fit for medical tubing for decades. But as minimally invasive devices navigate more complex anatomies and demand more differentiated mechanical behavior, a single PTFE formulation can no longer serve the full range of design requirements. FlexaCast delivers more than twice the elongation of traditional ram extruded PTFE for devices that need to navigate and flex. DuraCast addresses wear resistance where repeated movement creates abrasion risk. UltraCast increases tensile strength for applications requiring structural rigidity. Confluent can also process customer-supplied PTFE formulations, which means the program is structured to expand design possibilities rather than constrain them.
Governance and Challenges
Medical device OEMs face compounding constraints at the material selection stage: regulatory compliance requirements vary by market, biocompatibility testing timelines are long and expensive to repeat, and mechanical performance tradeoffs are rarely visible until assembly or device testing reveals them. Selecting the wrong material early can mean validation rework that pushes launch timelines significantly. The FilmCast Select™ program is specifically designed to surface these tradeoffs before physical samples are committed to testing, using virtual performance modeling and collaborative design review to reduce the cost of getting material selection wrong.
Implementation and Strategy
The FilmCast Select™ process begins with a performance attribute conversation — identifying what the device actually needs from its tubing in terms of flexibility, strength, surface characteristics, and regulatory compliance. From there, the appropriate material platform is chosen and design optimization begins with Confluent’s engineering team involved as a partner, not just a supplier. Virtual modeling, cost analysis, and sample manufacturing are integrated into a single development workflow designed to accelerate the path from concept to commercialization.
Who Should Read This
This case study is essential reading for medical device R&D engineers and materials scientists evaluating tubing solutions for minimally invasive applications, regulatory and quality teams navigating REACH and biocompatibility requirements across global markets, and OEM program managers looking to reduce late-stage design changes by locking in the right material properties earlier in the development cycle.
Download the FilmCast Select™ Case Study: Accelerating Innovation in Filmcast Polymer Technology from Confluent to explore the full case details and understand how the program can be applied to your device’s specific material challenges. Reach out directly at sales@confluentmedical.com.
