High-Modulus Polyimide Offers Greater Catheter Design Flexibility

As medical device designs continue to evolve, there is constant design pressure to decrease wall thickness without sacrificing device performance. Conversely, other applications benefit from a reduction in the outer diameter while maintaining the existing inner diameter. In both cases, stronger materials allow for more options to conquer the design hurdles associated with the ongoing march toward thinner designs. In this Expert Insight, Shane Wood, Director of Technology, Polymers, and Dean Burke, Business Development Director at Confluent Medical Technologies talk with Medical Design Briefs about a game-changer for catheter manufacturing — a breakthrough material that delivers nearly twice the strength of traditional polyimide, providing unmatched performance and design flexibility.

Transcript

00:00:00 Welcome to this expert insight. I'm Sheri Trigg, editor and director of content with medical design briefs and we're here with Shane Wood, director of technology polymers and Dean Burke, business development director at Confluent Medical Technologies. They will talk to us about a gamecher for catheter manufacturing, a breakthrough material that delivers nearly twice the

00:00:24 strength of traditional polyimid providing unmatched performance and design flexibility. So, can you each uh start by telling us a bit about yourself and your role at Confluent? Yeah, I I can start Theory. So, my name is Dean Burke. I'm the business development director at Confluent. I'm based here at the Chattanooga, Tennessee

00:00:44 facility where we focus on filmcast technology. So, Teflon liners, polyimid tubing, variety of braided and coil constructions, uh and also balloons and balloon catheters. Um in my role, I work on the commercial side of the business. I help our sales directors identify, scope, and ultimately quote product for our customers. Uh I think one advantage uh being here onsite uh is because our

00:01:08 sales team is all remote, I'm kind of the liaison between our uh engineering and manufacturing staff. But good good to be here with you today. Thank you. And Sherry, I'm Shane Wood. Um I'm the director of polymer technology for Confluent Medical. Primarily acting two capacities. uh one I provide the engineering leadership for the Chattanooga site here with Dean and then

00:01:32 I also work with our various uh subject matter experts to identify technology priorities for our various businesses including filmcast extrusion balloons and complex gather businesses. So thank you for having us. Excellent. Thank you. Uh so diving in uh so ultra polyamid offers nearly double the strength of standard polyamid. How does this innovation enable the design of smaller

00:01:59 higher performance minimally invasive devices? Yes, Sher. So as as you know and and probably your viewers know poly is used in medical device manufacturing for a number of reasons um including thermal stability, chemical resistance uh insulative properties and as you mentioned in many cases it's for mechanical strength. The ultra polyamid

00:02:21 uh that we've been working on does ring approximately twice the strength of standard industry polyamid. And what that allows is it allows for thinner walls uh for the design team while still maintaining uh the me mechanical integrity of the tube. And that allows for more design cross-section to be used for other purposes that may be coil or braid reinforcement or for a larger

00:02:46 lumen for improved tool passage or fluid flow for example. Oh, excellent. So with the increased tensil and column strength uh what specific improvements can medical device engineers achieve in catheter guidewire and delivery system designs using the ultra polyamid? Yes. So you know S kind of alluded to it but the thought process behind our ultra polyamid was that it's higher strength.

00:03:13 It meant that the tubing walls could be thinner but achieve the same performance um in minimally invasive procedures. These thinwalled high performance tubing it's often used as a conduit. Uh these passages they can carry a variety of different things such as guide wires, biopsy tools. They can provide support for mechanical throbectomy devices or too they can be used for fluid

00:03:39 transmission or for suction. Uh so the merits of this ultra polyamid is twofold. Um when you have a larger lumen, it gives more clearance to those tools that I mentioned. Uh it would also give you include in increased flow rates for uh either suction uh or materials. Um and then on the flip side, uh if you're trying to reduce the overall print size of the device, it could also

00:04:04 be helpful. Uh so medical device engineers often face tradeoffs between strength, wall thickness, and manufacturability. uh how does the ultra ultra polyimid help mitigate these challenges and what new design possibilities does it unlock? That's a great question. Uh I think the key word in your question with trade-offs. So uh generally speaking uh

00:04:29 some attributes are at odds. Um for example a stiff tube it will not have a good kink resistance. Um but conversely um a flexible calf it would not be good um with regards to column strength or pushability. So uh what I tell customers all the time uh the beauty of our film cast process is it lends itself well to composite construction. So when you think about it as a whole uh there are

00:04:54 two liner materials that we can apply teflon and polyid that we're talking about. uh you have the ability to uh add braid or coil reinforcement and within that uh you have a variety of different stainless steel sizes both round and flat. Uh you can also vary the coil pitch uh the ps per inch from a braid standpoint. Uh and then um from an outer jacket perspective you can go back over

00:05:19 that with polyamid or a variety of different thermoplastics such as debbacks or thermoplastic polyurethanes. Um so when you think about that there's just a myriad of different possibilities uh that you know a design engineer can use. Um so with the launch of our ultra polyid we're actually giving customers now two different options that have different uh performance characteristics

00:05:44 and you know I think this is is important so that they can kind of hone in on the optimal performance. um they want to distinguish themselves in uh the market where there's a lot of competition. Right. Right. Well uh now so with poly uh ultra polyamids uh reach compliance and restricted substancefree manufacturing process what advantages does this bring to medical

00:06:10 device developers in terms of regulatory compliance and even long-term supply chain sustainability? Yeah, I think we have some great benefits there. Uh Sherry, you know, as you guys are aware, Confluent Medical was the first to introduce a reach compliant polyamid formulation to the market uh in June of 2023. Um and and Temp manufacturers

00:06:33 historically have had uh various approaches to this compliance dilemma. Our approach has always been the easiest pathway for our customers. Easy compliance um with no restricted substances. Um this has become even more important as um environmental scrutiny also in the US has ratcheted up with uh with regard to NMP or the main solvent utilized in polyamin manufacturer. Um so

00:07:05 again our reach compliant offering on our original polyamid you know has no restricted solvents um no supply chain uncertainty associated with those solvents and also no expensive or expensive testing for our customers. Um that's been so wellreceived in the market that that we decided to incorporate that same philosophy with our ultra polyamid offering. So it is

00:07:31 also being offered with uh no reach restricted substances to make it easier for our customers. Absolutely. Uh so in terms of mechanical performance, how does ultra polyamid compare to alternative high-performance polymer materials used in medical tubing such as peak or PTFE? Uh are there specific testing methodologies that you've used to validate its um superiority? Yeah, I

00:07:58 think that's a good question. A lot of times Dean and I are asked about uh better materials or maybe a better manufacturing process and we've always um tried to make it less about what is better and more about using our experience and our material science expertise to provide the best solution for the customer for their specific challenge and that can mean different uh

00:08:22 manufacturing processes or materials in different cases. PTFE, peak, polyamid, and a number of other um materials, some of which Dean mentioned earlier, are well suited for a variety of medical device applications. As you know, PTFE is is the gold standard for lubricity, and oftentimes the design engineers integrate that into their design for that reason. Yes. Um but it's also good

00:08:48 for um applications requiring high temperature stability. um it's it's important for its um inertness from a chemical perspective and it has high flexibility uh for neurological applications. Um in contrast peak and polyamid uh they're typically used for very different purposes often having um requirements to do with strength like we like you've mentioned. Um peak is

00:09:18 typically uh important for its toughness and u its ability to uh be well suited for long-term implement uh implantation whereas polyamid may be a better fit for u applications needing flexibility high temperature exposure and maybe dialectric strength. Oftentimes you ask a little bit about testing. So there's a variety of testing we can perform, but oftent times we we perform our initial

00:09:46 characterizations with tensil testing that gives us a a good picture of a lot of the performance attributes that we're talking about. Elastic modulus uh elongation and things like that. So there's a variety that we can use but um that's one of the main stays of of our characterization process. Interesting very interesting uh information. So given the continuous

00:10:09 evolution of medical device designs, what further enhancements or next generation developments do you foresee for polymer tubing materials beyond ultra polyamid? Are there new material properties or manufacturing techniques that uh Confluent Medical is exploring? Yeah, I'll take that one, Sherry. So uh here at Confluent, we hang our hat on innovation and I'll give Shane and her

00:10:33 engineering team a lot of credit. um they are constantly working on improvements not only to our equipment processes and material and I think you mentioned that earlier you know bringing reach compliant polyamid and reach compliant thermoplastics uh as well as the ultra polyamid that we've been talking about today um so they don't stop there you know we're continuing to

00:10:55 innovate um they've got several other things in Q uh one is teflon offerings we also have some process improvements that should uh improve improve the surface adhesion for polyamid tubing. Uh and then one big uh hot spot or topic in the medical device market is um lubricative non PAS alternatives. Um so they're actively pursuing those and uh we should probably in the next month or

00:11:22 so be making an announcement uh about a new ton offering. Excellent. Well, uh, thank you both for joining me today and providing your insights and your expertise. Uh, it was a pleasure to have you. Thank you so much. Thank you, Sher. We appreciate you guys having us.