Multifunctional Kaolin/PDMS Composite Bandage with Hemostatic, Absorptive, and Passive Radiative Cooling Properties

Effective wound dressings should not only protect injured tissues but also provide hemostatic performance, fluid management, and thermal regulation. In this study, a multifunctional kaolin/PDMS composite bandage containing 70 vol% kaolin was developed to simultaneously achieve bleeding control, absorption capability, and passive radiative cooling.

Kaolin particles were incorporated into a flexible PDMS matrix to fabricate the composite bandage. Optical characterization using UV–Vis–NIR and FT-IR spectroscopy revealed enhanced solar reflectance and high infrared emittance within the atmospheric window (8–13 μm). These optical properties enable passive radiative cooling by minimizing solar heat absorption while efficiently dissipating thermal energy through infrared radiation.

Outdoor cooling experiments demonstrated that the kaolin/PDMS composite exhibited lower surface temperatures than a commercial first-aid bandage under direct sunlight, indicating superior thermal management performance. The improved cooling behavior was attributed to the synergistic effect of high solar reflectance and strong infrared emittance.

In addition, water and artificial blood absorption tests confirmed effective fluid-handling capability, suggesting suitability for wound exudate management. The presence of kaolin also provides inherent hemostatic functionality through activation of the coagulation pathway, further enhancing the practical utility of the bandage.

These results demonstrate that the developed kaolin/PDMS composite successfully integrates hemostatic performance, absorption capability, and energy-free thermal regulation into a single platform. The proposed material shows strong potential as a next-generation wound dressing for improving both bleeding control and patient comfort