Reusable and Porous Skin Patches with Thermopneumatic Adhesion Control Capability and High Water Vapor Permeability.

We present a reusable and porous skin patch (RPS patch) capable of controlling adhesion force with a thermal-pneumatic method for repetitive use as well as improving moisture permeability for long-term use without skin troubles. Previous skin patches cause skin troubles due to high adhesion force (∼30 kPa) and low moisture permeability (∼382 g/m/day), hindering them from repeatable and long-term use. We control the skin adhesion force of the RPS patch using thermopneumatic pressure generated by an embedded heater on multiple chamber arrays. The RPS patch controls the adhesion force ranging from 8 to 29 kPa on both dry and wet skin while keeping the stable adhesion force for 48 h. It shows repeatable adhesion up to 100 times, and the adhesion force is restored after the RPS patch is washed with water, thus enabling repetitive skin adhesion. We improve the moisture permeability of the RPS patch to 733 g/m/day while maintaining the adhesion force by making the RPS patch with porous materials. The RPS patch shows no skin troubles for 7 days of attachment, thereby being available for long-term skin attachment. The RPS patch, having adhesion control capability and high moisture permeability, shows potential for use in daily life in biomedical applications, including wearable sensors, medical adhesives, and rehabilitation robots.