New Super‐Absorbent Composite Film for Improving the Hot and Humid Environment Inside Anti‐Epidemic Protective Clothing

Abstract When healthcare workers wear personal protective equipment (PPE) for long periods of time during high‐risk disease transmission, the trapped heat and excessive humidity inside the PPE often disrupt the skin's surface microclimate and impair its natural protective barrier. In this study, a super‐absorbent composite film that can be used inside protective clothing is synthesized using high film‐forming Polyvinyl Alcohol (PVA), doped with Hollow Mesoporous Silica Nanoparticles (HMSN) as a platform for cross‐linking networks, and highly absorbent calcium chloride (CaCl 2 ). The water‐absorbing capacity and biosafety of this composite film are investigated, and the improvement of skin microclimate before and after its use by the participants is verified. With a moisture absorption capacity of 157 g m −2 , the film is able to reduce 90% of the humidity inside PPE to ≈40% within 1 h, and lowered the skin temperature by 1.5 °C, keeping the skin microclimate in equilibrium. The hydrated hygroscopic film is reusable and degradable. The present study offers a new approach to alleviate the problem of excessive heat and humidity within protective garments amid epidemics, and this strategy can be further extended to tackle analogous challenges in scientific research, occupational settings, and daily life.