Solvent-free atmospheric plasma coatings for tunable, durable wetting control

Overview

This technology uses atmospheric-pressure plasma to deposit nanometre-thin, covalently anchored polymer coatings that control surface wetting on demand. By selecting precursor chemistry and adjusting plasma energy, the coating can tune water contact angles from hydrophilic (<10°) to hydrophobic (>150° with surface texture) on polymer films, nonwovens, metals, and glass. The process is dry, solvent-free, near room temperature, and compatible with roll-to-roll manufacturing, making it suitable for consumer goods, medical materials, packaging, and fluid-handling applications.

The core value is durable wetting control without altering bulk properties. Because only the outermost nanometres of the surface are modified, mechanical strength, feel, and optics remain unchanged. Crosslinked plasma-polymer films resist hydrophobic recovery—a common failure of conventional plasma activation—and maintain stable surface energy against ageing, washing, and abrasion.

Technical specifications

How it works:

• A precursor vapour or aerosol is fed into a dielectric barrier discharge or plasma jet.
• Plasma-generated surface radicals covalently anchor a crosslinked film 10–100 nm thick.
• Precursor chemistry can include siloxane, fluorine-free hydrocarbon, carboxyl, amine, or PEG-like chemistries.
• Energy input per monomer tunes water contact angle and film properties.

Capabilities:

• Write wetting patterns and gradients using rastered jets or masks to direct pinning and fluid transfer.
• Add nanoscale roughness by plasma etching in the same line for combined chemistry–topography surfaces.
• Achieve water contact angles from <10° to >150° (the latter requires surface texture).
• Process operates continuously at web speed with second-scale residence, minimal precursor use, no solvent waste, and no cure step.

Applications: surface-energy mapping, patterned wetting for fluid control, low-friction or tuned-transfer coatings, durable hydrophobic/hydrophilic finishes, and hybrid topography–chemistry surfaces.

Technology readiness level

The technology is at the proof-of-concept stage. The proposing laboratory has an established plasma-coating track record and proposes a 12-month, three-phase sponsored research program: baseline and chemistry screening, pattern and friction tuning, and durability and scale-up validation. The first phase would produce a surface-energy map and coated coupons; later phases would include storage ageing, rub/wash cycling, and process-window definition. No commercial deployment is claimed.