Adhesion Matters
Adhesion Matters pulls back the curtain on the remarkable world of adhesives—the invisible technologies quietly revolutionizing everything from smartphones and EVs to Hollywood effects and wind turbines. We guide listeners on a deep-entangled journey through innovation, sustainability, and the surprising human stories behind the products that hold our modern life together.
Adhesion Matters isn’t just about chemistry—it’s a storytelling lens on how sticky stuff shapes our world. Every episode reveals that adhesives do more than bind—they enable durability, safety, and innovation across industries. Tune in if you’re curious about the overlooked tech that really holds things together.
Adhesion Matters
Sealing the Smallest Molecule: Adhesives for Hydrogen & Fuel Cells
How do you seal the most elusive molecule in the universe? In this episode of Adhesion Matters, we explore the unique role adhesives and sealants play in the hydrogen economy. From membrane–electrode assemblies (MEAs) in fuel cells to valves, pipelines, and high-pressure tanks, hydrogen’s small size creates extraordinary challenges: permeation, embrittlement, and cyclic fatigue.
We highlight sealant chemistries that can stand up to these demands—including silicones, fluorosilicones, and hybrid polymers—and explain how companies like Dow and Henkel are engineering hydrogen-ready sealing solutions. We also dive into ISO and SAE test standards that define allowable leak rates and durability benchmarks, and look ahead at innovations such as self-healing sealants and seal-in-place gasketing.
Whether it’s cars, trucks, ships, or stationary power, hydrogen fuel cells depend on adhesives that keep the smallest molecule safely under control. This episode shows how the right chemistry is critical for scaling the hydrogen future.
Welcome back to the Deep Dive. Today, we're diving into, well, a really fascinating paradox, hydrogen. You know, it's the smallest element on the periodic table, but somehow it creates some of the biggest, most complex sealing dilemmas imaginable. We're going to pull back the curtain a bit on the hidden world of advanced adhesives and sealants. These are kind of the unsung heroes, absolutely essential for making the hydrogen economy safe, efficient, and, you know, truly scalable.
Elena Bondwell:Exactly. And our mission today really is to guide you through the, let's say, the intricate material science behind keeping hydrogen contained. We'll look at the specific innovations The industry collaborations too, we've got insights from key players like Bodo Möller Chemie, Dow, Henkel, companies really working to overcome these challenges. Yeah, the goal is to leave you thoroughly informed on this pivotal technology. Understanding the fundamental hurdles, sure, but also appreciating the ingenious solutions making it all possible.
Lucas Adheron:Okay, so we started by calling hydrogen a paradox. Tiny element, huge challenges. Let's unpack why. What makes this smallest of elements such a... such a nightmare to keep contained. Why is sealing it effectively so incredibly difficult?
Elena Bondwell:It really all boils down to its inherent characteristics. I mean, as the smallest molecule, hydrogen has exceptionally high permeability. What that actually means is hydrogen molecules can just sort of slip through materials that would easily hold back much larger gases. It's like imagine trying to hold water in a fishing net, but on a molecular scale. These tiny hydrogen particles are just constantly probing, looking for any micro pathway out.
Lucas Adheron:So it's not just finding a way out. It's always trying to find a way out, even through materials that seem solid.
Elena Bondwell:Precisely. And it gets worse. Beyond just escaping, there's a much more, well, insidious problem, hydrogen embrittlement. This is a really critical phenomenon where hydrogen atoms don't just leak past the material, they actually diffuse into it. Into the seal, yes, but also into adjacent metals. And when these hydrogen atoms get inside the material structure, they can weaken the atomic bonds, especially under cyclic loading, pressure changes again and again in a tank or pipeline. This process, it compromises the material's tough makes it brittle and highly susceptible to sudden failure. So we're not just talking about a slow leak. We're talking about potentially undermining the structural integrity of the whole system. And frankly, that's why your standard elastomers, your typical sealants, they often just aren't up to the job. They weren't designed for this kind of dual attack.
Lucas Adheron:Right. So if hydrogen weakens both the seal and the metal next to it, Does that mean we need completely new types of metal alloys too, not just bitter sealants? Is it a dual challenge?
Elena Bondwell:That's a really sharp point. Yes. While today we're focused on the adhesives and sealants, you're absolutely right. The broader hydrogen economy often demands specialized alloys and materials throughout the system specifically designed to resist this embrittlement. It's definitely a multifaceted material science puzzle, and seals are a very visible, very critical piece of it.
Lucas Adheron:Okay. That makes total sense. So we're talking serious risks then, not just losing efficiency, but real safety concerns, especially at those weak points like, say, threaded connections, where even a microscopic leak could be disastrous.
Elena Bondwell:Exactly. And if we zoom in on a key application like fuel cell stacks, the role of these adhesives and sealants becomes even clearer. Think about the core of a fuel cell, the membrane electrode assembly, the MEA, you've got hydrogen, oxygen, and coolant channels all packed tightly together, often under pressure, maintaining absolutely perfect gas tight separation between them isn't just important. It's well, it's non-negotiable for performance and definitely for safety.
Lucas Adheron:OK, so even tiny breaches in that MEA, what does that actually lead to? What are the real world consequences?
Elena Bondwell:Well, even minuscule leaks there can cause significant efficiency drops right away because the gases mix and compromise the reaction. This quickly leads to performance degradation. It shortens the life of these, frankly, very expensive fuel cell stacks. And in the worst case, yeah, system failure or safety issues. It hits the economics and the safety case hard.
Lucas Adheron:Wow. Okay. So the slippery nature of hydrogen plus this embrittlement, it really makes standard sealing methods insufficient, which means we need some seriously advanced material science. So how are engineers tackling this? What are the key chemistries, the product innovation stepping up to the plate and who's behind them?
Elena Bondwell:Yeah, this is where the innovation is really exciting. We're seeing several categories of advanced solutions emerge. Companies like Dow, Henkel, they're really at the forefront here. And importantly, you have trusted global partners, specialists in advanced adhesive tech like Bodo Möller Chemie, who are key in actually recommending and distributing these cutting edge solutions, getting them into the right hands in industry.
Lucas Adheron:OK, before we get right into sealing the hydrogen itself, Let's touch on managing heat because these systems run hot, right? Our sources talk about something called Dalsol TC3065 thermal gel. What makes this specific silicone gel stand out for thermal management, especially maybe in manufacturing?
Elena Bondwell:Ah, yes. The Dalsol TC3065 thermal gel. It's quite an interesting material. It's a one-part thermally conductive gel, easy to dispense, curable, primarily for dissipating heat, keeping things cool. But the really key property, the thing that makes it stand out is its reworkability. It cures into this kind of elastic pad.
Lucas Adheron:Elastic pad.
Elena Bondwell:Yeah. And you can peel it off completely. No residue left behind. Think about what that means for manufacturing.
Lucas Adheron:Ah, okay. So if something goes wrong with a component.
Elena Bondwell:Exactly. You can salvage it. Reclaim damaged or defective units like complex PCB assemblies. It prevents scrapping expensive parts, speeds up prototyping. It's a huge deal for reducing waste and cost and boosting innovation speed.
Lucas Adheron:That reworkability sounds like a game changer, honestly. Not just cost, but speed and quality control. What about its main job, the thermal performance.
Elena Bondwell:Right. It's not just about fixing mistakes. It delivers excellent thermal performance, too. It has an impressive 6.5 watts per meter Kelvin thermal conductivity. That's crucial for keeping power devices cool under load. It's often used as a thermal interface material, say, for optical transceivers or just general thermal management on PCB systems. And it's durable, resists humidity, harsh environments, doesn't crack or slump. Plus, it's flexible in how you apply and cure it. Automated dispensing, screen printing, You can cure it relatively quickly at higher temps, like 120 degrees C, or take longer at, say, 100 degrees C. It even has a long working time, over five days at room temp, which gives manufacturers flexibility. And temperature-wise, it's built for 9 to 4.5, up to 150 degrees C long-term, potentially even colder after checks. So yeah, a very robust solution all around.
Lucas Adheron:Okay, super comprehensive for the heat side of things, performance, and manufacturing friendliness. Now let's pivot back to sealing the actual hydrogen inside the fuel cells. Dow also has a Dow CLAC TC3065 series But this sounds like it's specifically for fuel cell membranes and gaskets. What's the advanced chemistry doing the work here?
Elena Bondwell:Yes. That specific dowsile TC3665 series for fuel cells uses what are called selene-modified polymer adhesives. Think of them as advanced polymers with silicone components basically engineered for extreme durability and chemical stability in harsh environments. But the critical feature, and I really can't stress this enough for fuel cells, is their incredibly low outgassing.
Lucas Adheron:Low outgassing. Why is that so valuable? Because
Elena Bondwell:even tiny amounts of released chemicals or outgassing inside a PM fuel cell can contaminate sensitive components like the catalyst. This acts like a poison, degrading performance over time, drastically shortening the stack's life, leading to premature failure. It's absolutely critical for long-term reliability and the economics of these systems. So these materials provide strong sealing, robust performance, especially in demanding areas like heavy-duty hydrogen transport. They really tackle those core challenges in fuel cell design head-on They're valued for durability, chemical stability, temperature resistance. It reinforces Dow's strength in this area, you know, within their wider Dow cell range.
Lucas Adheron:Got it. That outcasting point really clarifies the so what for system longevity and cost. Okay, let's tackle another big one. Thread sealing. You flagged it earlier as a P failure point. Microscopic leaks, there are a serious risk, right? Especially across the whole hydrogen infrastructure. Our sources highlight Henkel's all-CTIT portfolio, recommended by Bodo Möller Chemie here. What specific L'Occitane solutions are tackling this challenge?
Elena Bondwell:Right. For those critical threaded connections, and there are loads of them in any hydrogen system, Henkel's L'Occitane range, as highlighted by Boda Mellor-Kemme, offers several options that are actually hydrogen certified. And that certification is key. They meet QA GasTech QARR 214. That's a tough, globally recognized standard specifically for hydrogen service. It proves they can handle it.
Lucas Adheron:Okay. So what are some examples?
Elena Bondwell:Well, first up, there's L'Occitane 55. This one's quite unique. It's not a paste or liquid. It's a non-curing, multifilament thread seal cord.
Lucas Adheron:A cord, like a string.
Elena Bondwell:Sort of, yeah. You wrap it around the threads, the big advantage. It gives an immediate full-pressure seal, but you can still easily readjust the fitting later without damaging the threads or losing the seal integrity. Really handy for high-pressure hydrogen fittings where precise alignment might be needed during install or maintenance.
Lucas Adheron:Interesting. Okay, what else?
Elena Bondwell:Then you have Locte 567. This is a high-viscosity paste. It's an anaerobic cure.
Lucas Adheron:Meaning it cures without air.
Elena Bondwell:Exactly. Cures when it's confined between metal threads. It's designed for lower pressure instant sealing on threaded pipes. Works with both common thread types, BSPT and NPT, and it's got that GASTEC hydrogen certification. Okay. Similar, but different, is LOX-DT-577. This one's yellow, also an anaerobic paste, but offers medium strength, and it's particularly good at resisting vibration. Seals and locks metal threads, great chemical resistance, also hydrogen certified. Got it.
Lucas Adheron:Medium strength, vibration resistant. resistant.
Elena Bondwell:And finally, LOGTEET 638. This is a green anaerobic adhesive known for its really high shear strength. While its typical job might be retaining bearings on shafts, its super strong bond makes it excellent for ensuring high pressure or extreme environment. Threaded connections and hydrogen systems stay absolutely leakproof, provides that extra layer of security.
Lucas Adheron:So what's really interesting here is the range. You've got this flexible cord for adjustability, then different pastes for varying Right up to a high-strength
Elena Bondwell:adhesive. where you need to tweak angles. But for the absolute maximum pressure containment or situations where you need a permanent rock-solid bond and you know you won't need to adjust it later, then yes, an anaerobic paste like the high-strength LOX-T638 once fully cured might provide that ultimate level of security. It really depends on the specific application's demands and the risk assessment. You pick the right tool for the job.
Lucas Adheron:Right. It highlights how many different engineering needs there are. But, you know, just developing these fancy materials isn't the whole story, is it? You mentioned certification. Rigorous testing and global standards must be absolutely critical for safety and performance.
Elena Bondwell:Oh, absolutely. The regulatory and standards landscape is fundamental. You can't just say it works. You need proof. We're talking about crucial standards like ISO 1467 that defines hydrogen fuel quality itself, which affects materials, and SAE J2601, which covers safe fueling protocols. Beyond that, you need standards that set allowable permeation thresholds, leak rates for things like automotive fuel cells, give Even how licky hydrogen is, you need clear benchmarks for safety. Makes sense. And then underpinning all that are robust regulatory frameworks, you know, EU hydrogen safety rules, Japan's MIFI guidelines, U.S. Department of Energy test standards. They all work together to ensure these technologies are deployed responsibly and reliably everywhere.
Lucas Adheron:Yeah. It's clear that this strong regulatory net is essential for public trust and widespread adoption. It's not just making a good seal. It's proving objectively that it can stand up to the toughest demands day after day. So if we connect all these dots, the material science, the specific products, the standards, what's the bigger picture? Where is this heading? How are these adhesive and sealant innovations actually shaping the future of hydrogen, making more viable across different sectors?
Elena Bondwell:Well, the impact is becoming really broad. In mobility, we see their importance daily in fuel cell cars, trucks, buses, not just sealing the stack, but also integrating those high pressure tanks safely. And it's pushing into tougher areas, too, like hydrogen aviation and marine applications. Think about the vibrations and the temperature cycles, the constant pressure changes there, the sealing challenge is immense. Beyond transport, these materials are vital for stationary power, backup energy systems, and really for the entire hydrogen ready infrastructure. Compressors, pipelines, valves, they all need to handle hydrogen safely and reliably. And looking ahead, our sources hint at some really cool future possibilities. Things like adhesive enabled seal in place gaskets, imagine simplifying assembly and boosting durability that way, or even self-healing sealants designed for super long service life that could really push the boundaries of reliability and reduce maintenance needs significantly. You know, it raises this fundamental question, just how much do these often invisible technologies, these advanced adhesives and sealants, underpin the entire scalability and safety of the hydrogen economy? How are they turning this notoriously difficult molecule into a practical energy solution, silently making it all work?
Lucas Adheron:Wow. What an incredible deep dive. It really drives home that sealing hydrogen isn't some minor detail. It's a massive material science hurdle and these advanced adhesives these gels these thread sealants they are absolutely critical enablers they're right at the heart of making a safer cleaner and genuinely scalable hydrogen future actually happen quietly bridging that gap from potential to reality
Elena Bondwell:exactly right and maybe a final thought for everyone listening Consider how these invisible heroes we talked about today, the adhesives, the sealants, are working silently behind the scenes. They're making something as tricky as hydrogen practical for everyday use. So what other invisible technologies, things we barely notice, are shaping our future in profound ways, making the seemingly impossible possible?
Lucas Adheron:That's an excellent thought to chew on and a great reminder of the hidden ingenuity all around us. We definitely encourage you to keep exploring these fascinating topics. The whole world of material science is just full of surprises. Until next time on The Deep Dive, keep digging deeper.
