By: ICN Bureau
Last updated : December 06, 2025 9:45 am
Meeting the extreme demands inside proton exchange membrane (PEM) fuel cells is no small challenge
Humidifiers, which must survive continuous heat, chemical exposure and intense moisture, rely heavily on the durability and purity of the materials used in their construction.
But Germany's WEVO-CHEMIE says its latest range of polyurethane-, epoxy- and silicone-based adhesives, sealants and potting compounds is engineered precisely for that environment.
The company highlights gas-tightness, hydrolysis resistance, ion purity and low VOC content as critical factors for protecting the sensitive membrane at the heart of every fuel cell. Its new 2K systems are designed for long service life and can be fine-tuned for both semi- and fully automated production lines.
Humidifying incoming air is essential “for maintaining the conductivity of the membrane – and thus the efficiency of the entire system.” That job in PEM fuel cells typically falls to flat-sheet membrane and hollow fibre membrane humidifiers — both of which require extremely reliable bonding and sealing solutions.
These humidifiers can incorporate hundreds of delicate membrane and spacer layers that must be permanently bonded into a stable, gas-tight stack. WEVO’s hydrophobic adhesives and potting compounds have been developed specifically for this task. Their water-repellent polymer backbone also enables use as hydrolysis- and temperature-resistant sealants.
The company says its 2K polyurethanes and silicones achieve strong adhesion even on difficult substrates such as polyolefins, polyphenylene sulphide (PPS) and fluorinated membrane materials — long considered bonding challenges for the industry.
Another key feature is a low glass transition temperature, which ensures “high tear resistance, long-lasting elasticity and resistance to temperature changes” crucial during cold starts.
In hollow fibre systems, resin must flow between tightly packed membrane tubes without blocking them. WEVO says its potting compounds are engineered with “optimal exothermicity,” ensuring reaction heat remains controlled and avoiding oxidative damage to sensitive membranes. The company notes that its hydrophobic 2K polyurethane systems also resist reactions with membrane moisture, preventing bubble formation.
All materials in the new portfolio can be processed using standard mixing and dosing equipment. The company says properties such as viscosity and pot life can be customised, with most materials curing at room temperature — though thermal curing via convection ovens or infrared radiators can accelerate cycle times.
WEVO’s 2K systems can also be deployed throughout humidifier assemblies, including “sealing and bonding housings, for seals on water inlets and outlets, for sealing and bonding bypass valves, and for creating internally sealed zones.”
The company emphasises its close collaboration with manufacturers and research institutes, offering tailored formulations for fuel cells, electrolysers and balance-of-plant components. It says materials can be adjusted for specific requirements such as viscosity, adhesive strength and gas permeability — including hydrogen and water vapour — to support the sector’s rapid pace of innovation.