Durable Polymer-Engineered PDMS for Skin-Like Wetting and Fluid Transfer

Overview

This technology is a durable, thin polymer-engineered coating for silicone/PDMS surfaces that reproduces skin-like fluid interaction. Silicone/PDMS is chemically inert, low-energy, and highly flexible, which makes conventional surface treatments prone to instability or loss of performance. This approach uses a thin, crosslinked, and strongly anchored polymer layer to modify the silicone interface without substantially changing its bulk mechanical properties. The result is a surface that promotes controlled spreading, pinning, and transfer of complex aqueous fluids while suppressing undesirable beading, dewetting, and roll-off.

Potential applications include consumer products, personal care devices, medical devices, and any system where controlled fluid handling on soft, flexible silicone surfaces is important. The coating is designed for long-term stability and resistance to mechanical wear and cleaning, unlike temporary plasma activation or other conventional treatments.

Technical specifications

Key features:

• Covalently anchored polymer coating on silicone/PDMS for durable surface modification
• Tunable polymer composition, crosslinking, and surface functionality to achieve desired wetting behavior
• Controlled spreading, pinning, and transfer of complex aqueous fluids
• Suppression of beading, dewetting, and roll-off
• Target coefficient of friction of approximately 0.4–0.6
• Optional controlled micro/nanotopography for enhanced performance
• Designed for stability across repeated rubbing and cleaning cycles

Validation approach:

• Contact-angle hysteresis measurements to characterize wetting behavior
• Residual fluid area and smear/transfer testing to evaluate fluid handling
• Friction measurements to confirm target coefficient of friction
• Accelerated storage, mechanical rubbing, and repeated washing/cleaning tests to assess durability
• Surface chemistry and morphology characterization before and after aging

Technology readiness level

The technology is at an early development stage. The project will begin by preparing PDMS/silicone coupons and establishing baseline wettability, fluid pinning, transfer, and friction performance of unmodified silicone. Thin polymer coatings/brushes will then be developed using covalent surface functionalization, with polymer chemistry, grafting density, crosslinking, and film thickness systematically varied. Optimized surfaces will undergo accelerated storage, mechanical rubbing, and repeated washing/cleaning tests to assess durability. The final formulation will be validated on silicone coupons under representative movement/shear conditions and benchmarked against unmodified PDMS, delivering a scalable coating protocol and performance dataset.