Waterborne Polyurethane Porous Coating

Stable foam at 120°C

Templated from ultra-stable Pickering aqueous foams, eliminating VOC emissions with highly tunable microstructures.

Wu, Jianhui · Jiyu, Liang · Wang, Chunhua · Sheng, Yifeng · Ngai, To · Lin, Wei

Progress in Organic Coatings 2026

Specifications

Tensile strength

{'zh': '9.3', 'en': '9.3'} MPa

Elongation at break

{'zh': '322', 'en': '322'} %

T5%

{'zh': '275.8', 'en': '275.8'} °C

Softness

{'zh': '8.4', 'en': '8.4'} mm

Rebound resilience

{'zh': '317', 'en': '317'} ms

Water-vapor permeability

{'zh': '952', 'en': '952'} g/m²·d

Advantages

Foam stable at 120°C

The gel-like network formed via hydrogen bonding between WPU and N20 and the enhanced interfacial elasticity keep the foam stable at 120°C, enabling high-temperature drying.

Tunable mechanics

The microstructure and properties are readily tailored by adjusting N20 content; the optimized coating achieves tensile strength 9.3 MPa and elongation at break 322%.

Outperforms solvent-based

The resulting synthetic leather shows superior softness (8.4 mm), rebound (317 ms) and water-vapor permeability (952 g/m²·d) compared to solvent-based PU, with zero VOC emissions.

Applications

• Synthetic leather coatings：Replace solvent-based PU coatings, eliminating VOC emissions while achieving soft and breathable synthetic leather.
• Sustainable textiles：Coatings from aqueous foam templates are solvent-free and eco-friendly, advancing green textile manufacturing.
• Flexible porous materials：Provide flexible coatings with tunable porous structures for breathability and cushioning applications.