Design, Synthesis and Test of Paraffine-Petroleum-Nanocellulose-Based Phase Change Materials for Personal Cooling of Closed-Circuit Breathing Apparatus

We aim to integrate molecular modeling and experiments to develop innovative wax and oil-based phase change materials (PCMs) for thermal regulation in Closed-Circuit Self-Contained Breathing Apparatus (CC-SCBA) systems to reduce thermal burden, enhance operational longevity, and improve warfighter efficiency. These PCMs are lightweight, biocompatible, reusable, and regenerative with a tunable and stable transition temperatures. We use theoretical calculation to demonstrate that less than 0.4 kg PCM can regulate the inspired air temperatures for CC-SCBA below 35°C for over four hours with continuous usage, in compliance with NIOSH standards. The material can be recharged after usage. Combining molecular dynamics simulation and theoretical analysis, our study provides the recipe of the PCMs, its synthesis and validate its performance in a climate chamber, as well as its packaging to prevent leakage and ensure compatibility with existing CC-SCBA systems and durability in nearly 100% humidity working environment. This study aims to reduce temperature burden that improve CO2 scrubbing efficiency, reduce health risk, and significantly extend mission duration, providing a crucial tactical advantage in individial operations in extreme conditions.