High Hydrophobicity Polyurethane Acrylate Sensor with a Biomimetic Ionic Conductive Pathway for Health Monitoring

Polyurethane (PU) exhibits significant application value, owing to its outstanding elasticity, structural tunability, and potential for functional integration. However, the preparation of traditional PU suffers from long curing time and short service life, while the poor dispersion of inorganic conductive fillers tends to reduce the flexibility of the polymer matrix. Herein, polyurethane acrylate modified with disulfide bonds and double bond-terminated structures (PUSA) was synthesized via a solvent-free fabrication method. The material exhibits excellent mechanical properties, with a tensile strength of up to 9.7 MPa and a tensile strain of up to 310%. The incorporation of LiTFSI optimizes the ionic transport channels between the ionic liquid and PUSA, significantly enhancing the electrical conductivity of the material. The resulting sensor exhibits excellent mechanical and electrical properties, along with high repeatability and favorable hydrophobic retention during cyclic deformation. Furthermore, inspired by the high hydrophobic characteristics of duck feathers, the as-prepared film was engineered with biomimetic asymmetric barb microstructures, exhibiting outstanding hydrophobicity and moisture barrier performance, with a static water contact angle (WCA) of up to 147.88°. This investigation provides a promising pathway for the design and creation of flexible sensors in the fields of health monitoring and human–computer interaction.